Science.gov

Sample records for fixed wireless service

  1. 76 FR 35181 - Wireless Backhaul; Further Inquiry Into Fixed Service Sharing of the 6875-7125 and 12700-13200...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-16

    ... electronic news-gathering operations using TV pickup stations from interference due to FS operations, and... (FWCC) reports that BAS and CARS path and channel licensing, respectively, in the 13 GHz band have... its path within the service area of a co-channel TV pickup station. Additionally, the Commission...

  2. Development of fast wireless detection system for fixed offshore platform

    NASA Astrophysics Data System (ADS)

    Li, Zhigang; Yu, Yan; Jiao, Dong; Wang, Jie; Li, Zhirui; Ou, Jinping

    2011-04-01

    Offshore platforms' security is concerned since in 1950s and 1960s, and in the early 1980s some important specifications and standards are built, and all these provide technical basis of fixed platform design, construction, installation and evaluation. With the condition that more and more platforms are in serving over age, the research about the evaluation and detection technology of offshore platform has been a hotspot, especially underwater detection, and assessment method based on the finite element calculation. For fixed platform structure detection, conventional NDT methods, such as eddy current, magnetic powder, permeate, X-ray and ultrasonic, etc, are generally used. These techniques are more mature, intuitive, but underwater detection needs underwater robot, the necessary supporting tools of auxiliary equipment, and trained professional team, thus resources and cost used are considerable, installation time of test equipment is long. This project presents a new kind of fast wireless detection and damage diagnosis system for fixed offshore platform using wireless sensor networks, that is, wireless sensor nodes can be put quickly on the offshore platform, detect offshore platform structure global status by wireless communication, and then make diagnosis. This system is operated simply, suitable for offshore platform integrity states rapid assessment. The designed system consists in intelligence acquisition equipment and 8 wireless collection nodes, the whole system has 64 collection channels, namely every wireless collection node has eight 16-bit accuracy of A/D channels. Wireless collection node, integrated with vibration sensing unit, embedded low-power micro-processing unit, wireless transceiver unit, large-capacity power unit, and GPS time synchronization unit, can finish the functions such as vibration data collection, initial analysis, data storage, data wireless transmission. Intelligence acquisition equipment, integrated with high

  3. MPEG-2 encoded VoD series over fixed wireless channels using ARQ schemes

    NASA Astrophysics Data System (ADS)

    Ma, Hairuo; El Zarki, Magda

    1999-01-01

    In this paper, we investigated the possibility and effectiveness of applying ARQ schemes to the transmission of MPEG-2 encoded video streams over fixed wireless links in B- FWANs in video-on-demand services. Simulations were conducted to evaluate the overall system performance, which is then compared to a scheme using FEC with cell interleaving. Important metrics relevant to the broadband video services are analyzed, including the quality of the reconstructed video sequences, the excess delay and delay variation introduced by the ARQ scheme, the throughput, and the required average channel bandwidth. A hidden Markov model was also introduced to model the variation of the wireless channel.

  4. Transparent data service with multiple wireless access

    NASA Technical Reports Server (NTRS)

    Dean, Richard A.; Levesque, Allen H.

    1993-01-01

    The rapid introduction of digital wireless networks is an important part of the emerging digital communications scene. The introduction of Digital Cellular, LEO and GEO Satellites, and Personal Communications Services poses both a challenge and an opportunity for the data user. On the one hand wireless access will introduce significant new portable data services such as personal notebooks, paging, E-mail, and fax that will put the information age in the user's pocket. On the other hand the challenge of creating a seamless and transparent environment for the user in multiple access environments and across multiple network connections is formidable. A summary of the issues associated with developing techniques and standards that can support transparent and seamless data services is presented. The introduction of data services into the radio world represents a unique mix of RF channel problems, data protocol issues, and network issues. These problems require that experts from each of these disciplines fuse the individual technologies to support these services.

  5. Our Plan for a Wireless Loan Service.

    ERIC Educational Resources Information Center

    Allmang, Nancy

    2003-01-01

    Discusses the planning for wireless technology at the research library of the National Institute of Standards and Technology (NIST). Highlights include computer equipment, including laptops and PDAs; local area networks; equipment loan service; writing a business plan; infrastructure; training programs; and future considerations, including…

  6. Our Plan for a Wireless Loan Service.

    ERIC Educational Resources Information Center

    Allmang, Nancy

    2003-01-01

    Discusses the planning for wireless technology at the research library of the National Institute of Standards and Technology (NIST). Highlights include computer equipment, including laptops and PDAs; local area networks; equipment loan service; writing a business plan; infrastructure; training programs; and future considerations, including…

  7. Quality of service for tactical wireless networks

    NASA Astrophysics Data System (ADS)

    Ordower, Rick; Newman, Nisha; Myrtle, Jeremy

    2010-04-01

    Applications resident on tactical wireless networks are levying increasing offered loads. Tradeoffs can be made between range and throughput, but the wireless network is destined to be considered a limitation in information transfer. If managed correctly, the network can be an intelligent aid in ensuring the right information gets to the right place at the right time. Over the last 5 years, SAIC has worked with Natick Soldier Center (NSRDEC) to provide reliable communication with guaranteed service quality for the dismounted soldier. The effort utilizes a series of tools to mark, shape, condense, fragment and persist information for congestion and corruption control. The critical aspect of the congestion control solution is accomplished by adaptively throttling lower priority information at the sending node before it gets pushed to the wireless realm. Of note is that the solution adapts through passive processes without control messages. The solution also implements compression of messages and images, along with fragmentation techniques to alleviate congestion. Information corruption is purely a radio phenomenon and cannot be overcome through cognitive solutions. However, the solution mitigates corruption through information persistence and reliable retransmission. The implemented solution, unlike Transport Control Protocol, is optimized for wireless networks and demonstrates reduction of added signaling traffic. Combined congestion and corruption techniques have demonstrated how soldiers can get the right information at the right time during high traffic loads or network segmentation.

  8. Wireless intelligent network: infrastructure before services?

    NASA Astrophysics Data System (ADS)

    Chu, Narisa N.

    1996-01-01

    The Wireless Intelligent Network (WIN) intends to take advantage of the Advanced Intelligent Network (AIN) concepts and products developed from wireline communications. However, progress of the AIN deployment has been slow due to the many barriers that exist in the traditional wireline carriers' deployment procedures and infrastructure. The success of AIN has not been truly demonstrated. The AIN objectives and directions are applicable to the wireless industry although the plans and implementations could be significantly different. This paper points out WIN characteristics in architecture, flexibility, deployment, and value to customers. In order to succeed, the technology driven AIN concept has to be reinforced by the market driven WIN services. An infrastructure suitable for the WIN will contain elements that are foreign to the wireline network. The deployment process is expected to seed with the revenue generated services. Standardization will be achieved by simplifying and incorporating the IS-41C, AIN, and Intelligent Network CS-1 recommendations. Integration of the existing and future systems impose the biggest challenge of all. Service creation has to be complemented with service deployment process which heavily impact the carriers' infrastructure. WIN deployment will likely start from an Intelligent Peripheral, a Service Control Point and migrate to a Service Node when sufficient triggers are implemented in the mobile switch for distributed call control. The struggle to move forward will not be based on technology, but rather on the impact to existing infrastructure.

  9. Cross Service Fixed-Wing Cost Estimation

    DTIC Science & Technology

    2016-05-17

    making up the majority of fixed-wing costs , with occasional spikes in some of the other fields like 5.0 Continuing System Improvements. Category 6.0... Costs , a field that can differentiate widely between services and is not a key cost driver when evaluated with the Air Force Systems. The main cost ...TRAC-M-TR-16-021 May 2016 Cross Service Fixed-Wing Cost Estimation TRADOC Analysis Center 700 Dyer Road Monterey, California 93943-0692 This study

  10. Quality of service in wireless internet architectures

    NASA Astrophysics Data System (ADS)

    Salih, Omer; Lorenz, Pascal; Rao, Sathya

    2001-07-01

    The QoS in networks should provide consistent, predictable data service delivery to satisfy customers application requirements. A lot of different mechanisms enable to provide QoS, such as DiffServ, IntServ and MPLS. These mechanisms can be used for fixed and mobile communications.

  11. 47 CFR 15.307 - Coordination with fixed microwave service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Coordination with fixed microwave service. 15... Unlicensed Personal Communications Service Devices § 15.307 Coordination with fixed microwave service. (a... Private Operational-Fixed Microwave Service (OFS) operating under part 101 of this chapter to unlicensed...

  12. 47 CFR 15.307 - Coordination with fixed microwave service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Coordination with fixed microwave service. 15... Unlicensed Personal Communications Service Devices § 15.307 Coordination with fixed microwave service. (a... Private Operational-Fixed Microwave Service (OFS) operating under part 101 of this chapter to unlicensed...

  13. Ubiquitous and Secure Certificate Service for Wireless Ad Hoc Network

    NASA Astrophysics Data System (ADS)

    Ge, Meng; Lam, Kwok-Yan; Li, Jianbin; Chung, Siu-Leung

    Wireless ad hoc network is one of the most suitable platforms for providing communication services to support mobile applications in public areas where no fixed communication infrastructure exists. However, due to the open nature of wireless links and lack of security infrastructure in an ad hoc network environment, applications operating on ad hoc network platforms are subjected to non-trivial security challenges. Asymmetric key management, which is widely adopted to be an effective basis for security services in an open network environment, typically plays a crucial role in meeting the security requirements of such applications. In this paper, we propose a secure asymmetric key management scheme, the Ubiquitous and Secure Certificate Service (USCS), which is based on a variant of the Distributed Certificate Authority (DCA) - the Fully Distributed Certificate Authority (FDCA). Similar to FDCA, USCS introduces the presence of 1-hop neighbors which hold shares of DCA's private signature key, and can collaborate to issue certificates, thereby providing asymmetric key management service. Both USCS and FDCA aim to achieve higher availability than the basic DCA scheme; however, USCS is more secure than FDCA in that the former achieves high availability by distributing existing shares to new members, rather than generating new shares as the FDCA scheme does. In order to realise the high availability potential of USCS, a share selection algorithm is also proposed. Experimental results demonstrated that USCS is a more secure approach of the DCA scheme in that it can achieve stronger security than FDCA while attaining high availability similar to that of FDCA. Experiments also showed that USCS incurs only moderate communication overheads.

  14. Diagnosing degradation of services in hybrid wireless tactical networks

    NASA Astrophysics Data System (ADS)

    Tati, Srikar; Novotny, Petr; Ko, Bong Jun; Wolf, Alexander; Swami, Ananthram; La Porta, Thomas

    2013-05-01

    In this paper, we consider a problem related to service management and deployment in tactical military networks. Tactical networks are typically hybrid wireless networks in which there are both static and mobile nodes with several wireless interfaces, such as 802.11, 3G, satellite, etc. In tactical networks, performance degradation in services could prove fatal, so it must be diagnosed quickly. This degradation could be due to mobility or bottlenecks in capacity at network layer. We provide a cross-layer framework to detect and diagnose these causes of performance degradation as part of service management; it includes a monitoring model of services and a network model for hybrid wireless networks. In addition, we give a working example in tactical military networks to illustrate our framework. We provide an experimental setup to simulate our hybrid wireless tactical network scenario along with preliminary results.

  15. 48 CFR 46.304 - Fixed-price service contracts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Fixed-price service... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 46.304 Fixed-price service contracts. The contracting officer shall insert the clause at 52.246-4, Inspection of Services—Fixed-Price, in solicitations...

  16. 48 CFR 46.304 - Fixed-price service contracts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Fixed-price service... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 46.304 Fixed-price service contracts. The contracting officer shall insert the clause at 52.246-4, Inspection of Services—Fixed-Price, in solicitations...

  17. 48 CFR 46.304 - Fixed-price service contracts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Fixed-price service... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 46.304 Fixed-price service contracts. The contracting officer shall insert the clause at 52.246-4, Inspection of Services—Fixed-Price, in solicitations...

  18. 48 CFR 46.304 - Fixed-price service contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Fixed-price service... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 46.304 Fixed-price service contracts. The contracting officer shall insert the clause at 52.246-4, Inspection of Services—Fixed-Price, in solicitations...

  19. 48 CFR 46.304 - Fixed-price service contracts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Fixed-price service... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 46.304 Fixed-price service contracts. The contracting officer shall insert the clause at 52.246-4, Inspection of Services—Fixed-Price, in solicitations...

  20. 47 CFR 15.307 - Coordination with fixed microwave service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Coordination with fixed microwave service. 15.307 Section 15.307 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unlicensed Personal Communications Service Devices § 15.307 Coordination with fixed microwave service. Each...

  1. 47 CFR 15.307 - Coordination with fixed microwave service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Coordination with fixed microwave service. 15.307 Section 15.307 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unlicensed Personal Communications Service Devices § 15.307 Coordination with fixed microwave service. Each...

  2. 47 CFR 15.307 - Coordination with fixed microwave service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Coordination with fixed microwave service. 15.307 Section 15.307 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unlicensed Personal Communications Service Devices § 15.307 Coordination with fixed microwave service....

  3. Quality of Service in Wireless Sensor Networks (QOS in WSN)

    NASA Astrophysics Data System (ADS)

    Zolhavarieh, Seyedjamal; Barati, Molood

    2013-03-01

    In this paper, we discuss about concept of Quality of Service (QoS) in Wireless Sensor Networks (WSN) and different methods to improve data security network. The most useful methods for network traffic control are Differentiated Services (DS), Integrated Services, Multi-Protocol Labeled Switching (MPLS), Resource Reservation Protocol (RSVP) and Traffic Engineering. Quality of Service is responsible for data transfer between different parts of the network and it guarantees some series of transport properties on the network [14].

  4. Next Generation RFID-Based Medical Service Management System Architecture in Wireless Sensor Network

    NASA Astrophysics Data System (ADS)

    Tolentino, Randy S.; Lee, Kijeong; Kim, Yong-Tae; Park, Gil-Cheol

    Radio Frequency Identification (RFID) and Wireless Sensor Network (WSN) are two important wireless technologies that have wide variety of applications and provide unlimited future potentials most especially in healthcare systems. RFID is used to detect presence and location of objects while WSN is used to sense and monitor the environment. Integrating RFID with WSN not only provides identity and location of an object but also provides information regarding the condition of the object carrying the sensors enabled RFID tag. However, there isn't any flexible and robust communication infrastructure to integrate these devices into an emergency care setting. An efficient wireless communication substrate for medical devices that addresses ad hoc or fixed network formation, naming and discovery, transmission efficiency of data, data security and authentication, as well as filtration and aggregation of vital sign data need to be study and analyze. This paper proposed an efficient next generation architecture for RFID-based medical service management system in WSN that possesses the essential elements of each future medical application that are integrated with existing medical practices and technologies in real-time, remote monitoring, in giving medication, and patient status tracking assisted by embedded wearable wireless sensors which are integrated in wireless sensor network.

  5. 64 Gbit/s Transmission over 850 m Fixed Wireless Link at 240 GHz Carrier Frequency

    NASA Astrophysics Data System (ADS)

    Kallfass, Ingmar; Boes, Florian; Messinger, Tobias; Antes, Jochen; Inam, Anns; Lewark, Ulrich; Tessmann, Axel; Henneberger, Ralf

    2015-02-01

    A directive fixed wireless link operating at a center frequency of 240 GHz achieves a data rate of 64 Gbit/s over a transmission distance of 850 m using QPSK and 8PSK modulation, in a single-channel approach without the use of spatial diversity concepts. The analog transmit and receive frontend consists of active monolithic integrated circuits including broadband RF amplification and quadrature subharmonic mixer channels. The analog frontend is addressed by 64 GSa/s ADC and DAC boards, which are amenable to real-time data transmission. A link budget calculation allows for the estimation of the performance under adverse weather conditions.

  6. Quantifying and Mitigating Privacy Threats in Wireless Protocols and Services

    DTIC Science & Technology

    2009-07-01

    Quantifying and Mitigating Privacy Threats in Wireless Protocols and Services Jeffrey Anson Pang CMU-CS-09-145 July 2009 School of Computer Science...of Washington Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Copyright c© 2009 Jeffrey Anson Pang This

  7. 47 CFR 0.482 - Application for waiver of wireless radio service rules.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Application for waiver of wireless radio... Taking Examinations § 0.482 Application for waiver of wireless radio service rules. All requests for waiver of the rules (see § 1.925 of this chapter) governing the Wireless Radio Services (see § 1.907 of...

  8. 47 CFR 0.482 - Application for waiver of wireless radio service rules.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Application for waiver of wireless radio... Taking Examinations § 0.482 Application for waiver of wireless radio service rules. All requests for waiver of the rules (see § 1.925 of this chapter) governing the Wireless Radio Services (see § 1.907 of...

  9. 47 CFR 0.482 - Application for waiver of wireless radio service rules.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Application for waiver of wireless radio... Taking Examinations § 0.482 Application for waiver of wireless radio service rules. All requests for waiver of the rules (see § 1.925 of this chapter) governing the Wireless Radio Services (see § 1.907 of...

  10. 47 CFR 0.482 - Application for waiver of wireless radio service rules.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Application for waiver of wireless radio... Taking Examinations § 0.482 Application for waiver of wireless radio service rules. All requests for waiver of the rules (see § 1.925 of this chapter) governing the Wireless Radio Services (see § 1.907 of...

  11. 47 CFR 0.482 - Application for waiver of wireless radio service rules.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Application for waiver of wireless radio... Taking Examinations § 0.482 Application for waiver of wireless radio service rules. All requests for waiver of the rules (see § 1.925 of this chapter) governing the Wireless Radio Services (see § 1.907 of...

  12. 47 CFR 80.705 - Hours of service of Alaska-public fixed stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Hours of service of Alaska-public fixed... SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Alaska Fixed Stations § 80.705 Hours of service of Alaska-public fixed stations. Each Alaska-public fixed station whose hours of service are not...

  13. 47 CFR 80.705 - Hours of service of Alaska-public fixed stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Hours of service of Alaska-public fixed... SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Alaska Fixed Stations § 80.705 Hours of service of Alaska-public fixed stations. Each Alaska-public fixed station whose hours of service are not...

  14. 47 CFR 80.705 - Hours of service of Alaska-public fixed stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Hours of service of Alaska-public fixed... SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Alaska Fixed Stations § 80.705 Hours of service of Alaska-public fixed stations. Each Alaska-public fixed station whose hours of service are not...

  15. 47 CFR 80.705 - Hours of service of Alaska-public fixed stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Hours of service of Alaska-public fixed... SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Alaska Fixed Stations § 80.705 Hours of service of Alaska-public fixed stations. Each Alaska-public fixed station whose hours of service are not...

  16. 47 CFR 80.705 - Hours of service of Alaska-public fixed stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Hours of service of Alaska-public fixed... SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Alaska Fixed Stations § 80.705 Hours of service of Alaska-public fixed stations. Each Alaska-public fixed station whose hours of service are not...

  17. 75 FR 43088 - Personal Communications Services and Miscellaneous Wireless Communications Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Parts 24 and 27 Personal Communications Services and Miscellaneous Wireless Communications Services CFR Correction In Title 47 of the Code of Federal Regulations, Parts 20 to 39, revised as of...

  18. Performance of an adaptive coding scheme in a fixed wireless cellular system working in millimeter-wave bands

    NASA Astrophysics Data System (ADS)

    Farahvash, Shayan; Akhavan, Koorosh; Kavehrad, Mohsen

    1999-12-01

    This paper presents a solution to problem of providing bit- error rate performance guarantees in a fixed millimeter-wave wireless system, such as local multi-point distribution system in line-of-sight or nearly line-of-sight applications. The basic concept is to take advantage of slow-fading behavior of fixed wireless channel by changing the transmission code rate. Rate compatible punctured convolutional codes are used to implement adaptive coding. Cochannel interference analysis is carried out for downlink direction; from base station to subscriber premises. Cochannel interference is treated as a noise-like random process with a power equal to the sum of the power from finite number of interfering base stations. Two different cellular architectures based on using single or dual polarizations are investigated. Average spectral efficiency of the proposed adaptive rate system is found to be at least 3 times larger than a fixed rate system with similar outage requirements.

  19. 75 FR 49871 - Fixed and Mobile Services in the Mobile Satellite Service

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-16

    ... COMMISSION 47 CFR Parts 1, 2 and 25 Fixed and Mobile Services in the Mobile Satellite Service AGENCY: Federal... Commission proposes to add co-primary Fixed and Mobile allocations to the existing Mobile-Satellite... mobile satellite capability to serve important needs like disaster recovery and rural access. DATES...

  20. Dynamic Hop Service Differentiation Model for End-to-End QoS Provisioning in Multi-Hop Wireless Networks

    NASA Astrophysics Data System (ADS)

    Youn, Joo-Sang; Seok, Seung-Joon; Kang, Chul-Hee

    This paper presents a new QoS model for end-to-end service provisioning in multi-hop wireless networks. In legacy IEEE 802.11e based multi-hop wireless networks, the fixed assignment of service classes according to flow's priority at every node causes priority inversion problem when performing end-to-end service differentiation. Thus, this paper proposes a new QoS provisioning model called Dynamic Hop Service Differentiation (DHSD) to alleviate the problem and support effective service differentiation between end-to-end nodes. Many previous works for QoS model through the 802.11e based service differentiation focus on packet scheduling on several service queues with different service rate and service priority. Our model, however, concentrates on a dynamic class selection scheme, called Per Hop Class Assignment (PHCA), in the node's MAC layer, which selects a proper service class for each packet, in accordance with queue states and service requirement, in every node along the end-to-end route of the packet. The proposed QoS solution is evaluated using the OPNET simulator. The simulation results show that the proposed model outperforms both best-effort and 802.11e based strict priority service models in mobile ad hoc environments.

  1. Dataman Project-Information Services for Low-Powered Wireless Mobile Clients

    DTIC Science & Technology

    2001-03-01

    DATES COVERED Final Report September 1995- December 2000 4. TITLE AND SUBTITLE Dataman Project- Information services for low-powered Wireless...goal of the research effort in the DataMan Project is the development of novel wireless information services, location-dependent

  2. 47 CFR 101.85 - Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... terrestrial fixed services to the fixed-satellite service (FSS). 101.85 Section 101.85 Telecommunication... Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite service (FSS...-satellite service (FSS). The rules in this section provide for a transition period during which...

  3. 47 CFR 101.85 - Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... terrestrial fixed services to the fixed-satellite service (FSS). 101.85 Section 101.85 Telecommunication... Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite service (FSS...-satellite service (FSS). The rules in this section provide for a transition period during which...

  4. 47 CFR 101.85 - Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... terrestrial fixed services to the fixed-satellite service (FSS). 101.85 Section 101.85 Telecommunication... Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite service (FSS...-satellite service (FSS). The rules in this section provide for a transition period during which...

  5. 47 CFR 101.85 - Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... terrestrial fixed services to the fixed-satellite service (FSS). 101.85 Section 101.85 Telecommunication... Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite service (FSS...-satellite service (FSS). The rules in this section provide for a transition period during which...

  6. 47 CFR 101.85 - Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... terrestrial fixed services to the fixed-satellite service (FSS). 101.85 Section 101.85 Telecommunication... Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite service (FSS...-satellite service (FSS). The rules in this section provide for a transition period during which FSS...

  7. An Initial Look at Adjacent Band Interference Between Aeronautical Mobile Telemetry and Long-Term Evolution Wireless Service

    DTIC Science & Technology

    2016-07-04

    LONG-TERM EVOLUTION WIRELESS SERVICE KIP TEMPLE AIR FORCE TEST CENTER EDWARDS AFB, CA 4 July 2016 4 1 2 T W...ADJACENT BAND INTERFERENCE BETWEEN AERONAUTICAL MOBILE TELEMETRY AND LONG-TERM EVOLUTION WIRELESS SERVICE 5a. CONTRACT NUMBER 5b...AT ADJACENT BAND INTERFERENCE BETWEEN AERONAUTICAL MOBILE TELEMETRY AND LONG-TERM EVOLUTION WIRELESS SERVICE Kip Temple Air Force

  8. Using Wireless Devices to Enhance Reference and Information Services

    ERIC Educational Resources Information Center

    Forsyth, Ellen

    2006-01-01

    A growing number of libraries have installed wireless data connections as a way of providing access to the Internet for members of the public. Some libraries have used their wireless networks to enable staff to use wireless devices to increase their mobility, effectiveness and responsiveness to client need particularly in providing reference and…

  9. Using Wireless Devices to Enhance Reference and Information Services

    ERIC Educational Resources Information Center

    Forsyth, Ellen

    2006-01-01

    A growing number of libraries have installed wireless data connections as a way of providing access to the Internet for members of the public. Some libraries have used their wireless networks to enable staff to use wireless devices to increase their mobility, effectiveness and responsiveness to client need particularly in providing reference and…

  10. Concepts and applications of wireless security systems for tactical, portable, and fixed sites

    SciTech Connect

    Harrington, J.J.

    1997-06-01

    Intrusion detection systems sometimes use radio signals to convey sensor status in areas that wire conduits do not service or as a redundant path to wired systems. Some applications benefit from radio technology by minimizing setup time and reducing installation and operation costs. In recent years with the explosion in wireless communications, these radio-based security systems have become more capable while lowering costs, size, and power consumption. However, the very nature of radio communication raises issues regarding setup, operation, and security of these systems. Sandia National Laboratories, in cooperation with government and industry, has addressed many of these issues through the analysis and development of security systems, communications protocols, and operational procedures. Message encryption and frequent channel supervision are used to enhance security. Installation and maintenance of these systems are simplified by incorporating built-in radio link analysis, menu-driven configuration equipment, and other techniques. Commercial communications satellites and spread-spectrum radios are also being integrated to provide unique capabilities to the security community. The status of this work is presented here along with details of its development.

  11. 48 CFR 1552.232-73 - Payments-fixed-rate services contract.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Payments-fixed-rate... Clauses 1552.232-73 Payments—fixed-rate services contract. As prescribed in 1532.111, insert the following in indefinite delivery/indefinite quantity contracts with fixed services rates. Payments—Fixed-Rate...

  12. Service Oriented Architecture for Wireless Sensor Networks in Agriculture

    NASA Astrophysics Data System (ADS)

    Sawant, S. A.; Adinarayana, J.; Durbha, S. S.; Tripathy, A. K.; Sudharsan, D.

    2012-08-01

    Rapid advances in Wireless Sensor Network (WSN) for agricultural applications has provided a platform for better decision making for crop planning and management, particularly in precision agriculture aspects. Due to the ever-increasing spread of WSNs there is a need for standards, i.e. a set of specifications and encodings to bring multiple sensor networks on common platform. Distributed sensor systems when brought together can facilitate better decision making in agricultural domain. The Open Geospatial Consortium (OGC) through Sensor Web Enablement (SWE) provides guidelines for semantic and syntactic standardization of sensor networks. In this work two distributed sensing systems (Agrisens and FieldServer) were selected to implement OGC SWE standards through a Service Oriented Architecture (SOA) approach. Online interoperable data processing was developed through SWE components such as Sensor Model Language (SensorML) and Sensor Observation Service (SOS). An integrated web client was developed to visualize the sensor observations and measurements that enables the retrieval of crop water resources availability and requirements in a systematic manner for both the sensing devices. Further, the client has also the ability to operate in an interoperable manner with any other OGC standardized WSN systems. The study of WSN systems has shown that there is need to augment the operations / processing capabilities of SOS in order to understand about collected sensor data and implement the modelling services. Also, the very low cost availability of WSN systems in future, it is possible to implement the OGC standardized SWE framework for agricultural applications with open source software tools.

  13. Simultaneous transmission of three services in a WDM-PON with wireless access for multicast data

    NASA Astrophysics Data System (ADS)

    Zhang, Liang; Wu, Yanzhi; Hu, Xiaofeng; Wang, Tao; Cao, Pan; Su, Yikai

    2010-12-01

    We propose and experimentally demonstrate a WDM-PON architecture supporting point-to-point, broadcast, and multicast services based on hybrid modulation format. Wireless access for multicast data is provided using optical carrier suppression (OCS) technology.

  14. Analysis of blocking rate and bandwidth usage of mobile IPTV services in wireless cellular networks.

    PubMed

    Li, Mingfu

    2014-01-01

    Mobile IPTV services over wireless cellular networks become more and more popular, owing to the significant growth in access bandwidth of wireless cellular networks such as 3G/4G and WiMAX. However, the spectrum resources of wireless cellular networks is rare. How to enhance the spectral efficiency of mobile networks becomes an important issue. Unicast, broadcast, and multicast are the most important transport schemes for offering mobile IPTV services over wireless cellular networks. Therefore, bandwidth usages and blocking rates of unicast, broadcast, and multicast IPTV services were analyzed and compared in this paper. Simulations were also conducted to validate the analytical results. Numerical results demonstrate that the presented analysis is correct, and multicast scheme achieves the best bandwidth usage and blocking rate performance, relative to the other two schemes.

  15. Analysis of Blocking Rate and Bandwidth Usage of Mobile IPTV Services in Wireless Cellular Networks

    PubMed Central

    Li, Mingfu

    2014-01-01

    Mobile IPTV services over wireless cellular networks become more and more popular, owing to the significant growth in access bandwidth of wireless cellular networks such as 3G/4G and WiMAX. However, the spectrum resources of wireless cellular networks is rare. How to enhance the spectral efficiency of mobile networks becomes an important issue. Unicast, broadcast, and multicast are the most important transport schemes for offering mobile IPTV services over wireless cellular networks. Therefore, bandwidth usages and blocking rates of unicast, broadcast, and multicast IPTV services were analyzed and compared in this paper. Simulations were also conducted to validate the analytical results. Numerical results demonstrate that the presented analysis is correct, and multicast scheme achieves the best bandwidth usage and blocking rate performance, relative to the other two schemes. PMID:25379521

  16. Expedition Three crew poses for photo on Fixed Service structure

    NASA Technical Reports Server (NTRS)

    2001-01-01

    KENNEDY SPACE CENTER, Fla. -- The Expedition Three crew poses on the Fixed Service Structure at Launch Pad 39A. From left are cosmonaut Mikhail Tyurin, commander Frank Culbertson and cosmonaut Vladimir Nikolaevich Dezhurov. The STS-105 and Expedition Three crews are at Kennedy Space Center participating in a Terminal Countdown Demonstration Test, a dress rehearsal for launch. The activities include emergency egress training, a simulated launch countdown and familiarization with the payload. Mission STS-105 will be transporting the Expedition Three crew, several payloads and scientific experiments to the International Space Station aboard Space Shuttle Discovery. The Expedition Two crew members currently on the Station will return to Earth on Discovery. The mission is scheduled to launch no earlier than Aug. 9, 2001.

  17. STS-105 crew poses for photo on Fixed Service Structure

    NASA Technical Reports Server (NTRS)

    2001-01-01

    KENNEDY SPACE CENTER, Fla. -- The STS-105 crew poses on the Fixed Service Structure at Launch Pad 39A. From left are Mission Specialist Patrick Forrester, Commander Scott Horowitz, Pilot Rick Sturckow and Mission Specialist Dan Barry. The STS-105 and Expedition Three crews are at Kennedy Space Center participating in a Terminal Countdown Demonstration Test, a dress rehearsal for launch. The activities include emergency egress training, a simulated launch countdown and familiarization with the payload. Mission STS-105 will be transporting the Expedition Three crew, several payloads and scientific experiments to the International Space Station aboard Space Shuttle Discovery. The Expedition Two crew members currently on the Station will return to Earth on Discovery. The mission is scheduled to launch no earlier than Aug. 9, 2001.

  18. General view looking out from the Fixed Service Structure at ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    General view looking out from the Fixed Service Structure at Launch Complex 39 B at Kennedy Space Center. This view shows a Solid Rocket Booster (SRB) attached to the External Tank (ET) as well as the Orbiter Discovery attached to the ET for a complete launch stack assembly being prepared for launch. The most prominent features of the SRB shown in this view id the ET Attach Ring in the lower center of the view and the Systems Tunnel running vertically from the Aft Skirt Assembly, beyond the lower edge of this view, to the Forward Skirt near the Frustum at the top center of this view. - Space Transportation System, Solid Rocket Boosters, Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  19. Multimedia wireless networking

    NASA Astrophysics Data System (ADS)

    Jain, Rajeev; Alwan, Abeer; Gerla, Mario; Kleinrock, Leonard; Villasenor, John D.; Belzer, Ben; Boring, Walter; Molloy, Stephen; Nazareth, Sean; Siqueira, Marcio; Short, Joel; Tsai, Jack

    1996-03-01

    Current wireless network systems (e.g. metropolitan cellular) are constrained by fixed bandwidth allocations and support only a narrow range of services (voice and low bit-rate data). To overcome these constraints and advance the state of the art in wireless multimedia communications, we are developing variable-rate video and speech compression algorithms, and wireless node architectures that will enable peer-to-peer multimedia networking even with very low bandwidth. To support this objective, each wireless node must support new applications (for multimedia), advances in networking and source coding to support multimedia under limited bandwidth conditions (wireless), advances in physical layer design to support robust, low power, high packet throughput links, low power DSP for multimedia compression, and an architectural strategy to integrate these components into an efficient node. The algorithms and architectures to support this functionality are presented here, together with some preliminary results on network performance.

  20. 48 CFR 52.249-8 - Default (Fixed-Price Supply and Service).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 2 2011-10-01 2011-10-01 false Default (Fixed-Price... Clauses 52.249-8 Default (Fixed-Price Supply and Service). As prescribed in 49.504(a)(1), insert the following clause: Default (Fixed-Price Supply and Service) (APR 1984) (a)(1) The Government may, subject to...

  1. 48 CFR 52.249-8 - Default (Fixed-Price Supply and Service).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Default (Fixed-Price... Clauses 52.249-8 Default (Fixed-Price Supply and Service). As prescribed in 49.504(a)(1), insert the following clause: Default (Fixed-Price Supply and Service) (APR 1984) (a)(1) The Government may, subject to...

  2. 48 CFR 52.249-8 - Default (Fixed-Price Supply and Service).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Default (Fixed-Price... Clauses 52.249-8 Default (Fixed-Price Supply and Service). As prescribed in 49.504(a)(1), insert the following clause: Default (Fixed-Price Supply and Service) (APR 1984) (a)(1) The Government may, subject to...

  3. Tradeoff Analysis for Combat Service Support Wireless Communications Alternatives

    SciTech Connect

    Burnette, John R.; Thibodeau, Christopher C.; Greitzer, Frank L.

    2002-02-28

    As the Army moves toward more mobile and agile forces and continued sustainment of numerous high-cost legacy logistics management systems, the requirement for wireless connectivity and a wireless network to supporting organizations has become ever more critical. There are currently several Army communications initiatives underway to resolve this wireless connectivity issue. However, to fully appreciate and understand the value of these initiatives, a Tradeoff Analysis is needed. The present study seeks to identify and assess solutions. The analysis identified issues that impede Interim Brigade Combat Team (IBCT) communication system integration and outlined core requirements for sharing of logistics data between the field and Army battle command systems. Then, the analysis examined wireless communication alternatives as possible solutions for IBCT logistics communications problems. The current baseline system was compared with possible alternatives involving tactical radio systems, wireless/near term digital radio, cellular satellite, and third-generation (3G) wireless technologies. Cellular satellite and 3G wireless technologies offer clear advantages and should be considered for later IBCTs.

  4. 47 CFR 1.1152 - Schedule of annual regulatory fees and filing locations for wireless radio services.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... locations for wireless radio services. 1.1152 Section 1.1152 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Schedule of Statutory Charges and Procedures for Payment § 1.1152 Schedule of annual regulatory fees and filing locations for wireless radio services. Exclusive use services...

  5. 48 CFR 1552.232-73 - Payments-fixed-rate services contract.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... services contract. 1552.232-73 Section 1552.232-73 Federal Acquisition Regulations System ENVIRONMENTAL... Clauses 1552.232-73 Payments—fixed-rate services contract. As prescribed in 1532.111, insert the following in indefinite delivery/indefinite quantity contracts with fixed services rates....

  6. 48 CFR 1552.232-73 - Payments-fixed-rate services contract.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... services contract. 1552.232-73 Section 1552.232-73 Federal Acquisition Regulations System ENVIRONMENTAL... Clauses 1552.232-73 Payments—fixed-rate services contract. As prescribed in 1532.111, insert the following in indefinite delivery/indefinite quantity contracts with fixed services rates....

  7. 48 CFR 1552.232-73 - Payments-fixed-rate services contract.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... services contract. 1552.232-73 Section 1552.232-73 Federal Acquisition Regulations System ENVIRONMENTAL... Clauses 1552.232-73 Payments—fixed-rate services contract. As prescribed in 1532.111, insert the following in indefinite delivery/indefinite quantity contracts with fixed services rates....

  8. 47 CFR 22.603 - 488-494 MHz fixed service in Hawaii.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false 488-494 MHz fixed service in Hawaii. 22.603 Section 22.603 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES... fixed service in Hawaii. Before filing applications for authorization of inter-island control and/or...

  9. 47 CFR 22.603 - 488-494 MHz fixed service in Hawaii.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false 488-494 MHz fixed service in Hawaii. 22.603 Section 22.603 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES... fixed service in Hawaii. Before filing applications for authorization of inter-island control and/or...

  10. 47 CFR 22.603 - 488-494 MHz fixed service in Hawaii.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false 488-494 MHz fixed service in Hawaii. 22.603 Section 22.603 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES... fixed service in Hawaii. Before filing applications for authorization of inter-island control and/or...

  11. 47 CFR 22.603 - 488-494 MHz fixed service in Hawaii.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false 488-494 MHz fixed service in Hawaii. 22.603 Section 22.603 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES... fixed service in Hawaii. Before filing applications for authorization of inter-island control and/or...

  12. 47 CFR 22.603 - 488-494 MHz fixed service in Hawaii.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false 488-494 MHz fixed service in Hawaii. 22.603 Section 22.603 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES... fixed service in Hawaii. Before filing applications for authorization of inter-island control and/or...

  13. Integration of hybrid wireless networks in cloud services oriented enterprise information systems

    NASA Astrophysics Data System (ADS)

    Li, Shancang; Xu, Lida; Wang, Xinheng; Wang, Jue

    2012-05-01

    This article presents a hybrid wireless network integration scheme in cloud services-based enterprise information systems (EISs). With the emerging hybrid wireless networks and cloud computing technologies, it is necessary to develop a scheme that can seamlessly integrate these new technologies into existing EISs. By combining the hybrid wireless networks and computing in EIS, a new framework is proposed, which includes frontend layer, middle layer and backend layers connected to IP EISs. Based on a collaborative architecture, cloud services management framework and process diagram are presented. As a key feature, the proposed approach integrates access control functionalities within the hybrid framework that provide users with filtered views on available cloud services based on cloud service access requirements and user security credentials. In future work, we will implement the proposed framework over SwanMesh platform by integrating the UPnP standard into an enterprise information system.

  14. Managing healthcare information using short message service (SMS) in wireless broadband networks

    NASA Astrophysics Data System (ADS)

    Documet, Jorge; Tsao, Sinchai; Documet, Luis; Liu, Brent J.; Zhou, Zheng; Joseph, Anika O.

    2007-03-01

    Due to the ubiquity of cell phones, SMS (Short Message Service) has become an ideal means to wirelessly manage a Healthcare environment and in particular PACS (Picture Archival and Communications System) data. SMS is a flexible and mobile method for real-time access and control of Healthcare information systems such as HIS (Hospital Information System) or PACS. Unlike conventional wireless access methods, SMS' mobility is not limited by the presence of a WiFi network or any other localized signal. It provides a simple, reliable yet flexible method to communicate with an information system. In addition, SMS services are widely available for low costs from cellular phone service providers and allows for more mobility than other services such as wireless internet. This paper aims to describe a use case of SMS as a means of remotely communicating with a PACS server. Remote access to a PACS server and its Query-Retrieve services allows for a more convenient, flexible and streamlined radiology workflow. Wireless access methods such as SMS will increase dedicated PACS workstation availability for more specialized DICOM (Digital Imaging and Communications in Medicine) workflow management. This implementation will address potential security, performance and cost issues of applying SMS as part of a healthcare information management system. This is in an effort to design a wireless communication system with optimal mobility and flexibility at minimum material and time costs.

  15. Prolonging the Lifetime of Wireless Sensor Networks Interconnected to Fixed Network Using Hierarchical Energy Tree Based Routing Algorithm

    PubMed Central

    Kalpana, M.; Dhanalakshmi, R.; Parthiban, P.

    2014-01-01

    This research work proposes a mathematical model for the lifetime of wireless sensor networks (WSN). It also proposes an energy efficient routing algorithm for WSN called hierarchical energy tree based routing algorithm (HETRA) based on hierarchical energy tree constructed using the available energy in each node. The energy efficiency is further augmented by reducing the packet drops using exponential congestion control algorithm (TCP/EXP). The algorithms are evaluated in WSNs interconnected to fixed network with seven distribution patterns, simulated in ns2 and compared with the existing algorithms based on the parameters such as number of data packets, throughput, network lifetime, and data packets average network lifetime product. Evaluation and simulation results show that the combination of HETRA and TCP/EXP maximizes longer network lifetime in all the patterns. The lifetime of the network with HETRA algorithm has increased approximately 3.2 times that of the network implemented with AODV. PMID:25535626

  16. Prolonging the lifetime of wireless sensor networks interconnected to fixed network using hierarchical energy tree based routing algorithm.

    PubMed

    Kalpana, M; Dhanalakshmi, R; Parthiban, P

    2014-01-01

    This research work proposes a mathematical model for the lifetime of wireless sensor networks (WSN). It also proposes an energy efficient routing algorithm for WSN called hierarchical energy tree based routing algorithm (HETRA) based on hierarchical energy tree constructed using the available energy in each node. The energy efficiency is further augmented by reducing the packet drops using exponential congestion control algorithm (TCP/EXP). The algorithms are evaluated in WSNs interconnected to fixed network with seven distribution patterns, simulated in ns2 and compared with the existing algorithms based on the parameters such as number of data packets, throughput, network lifetime, and data packets average network lifetime product. Evaluation and simulation results show that the combination of HETRA and TCP/EXP maximizes longer network lifetime in all the patterns. The lifetime of the network with HETRA algorithm has increased approximately 3.2 times that of the network implemented with AODV.

  17. Technical means for expanding the fixed-satellite service

    NASA Astrophysics Data System (ADS)

    Withers, D. J.

    1985-08-01

    In connection with the rapidly growing use of the geostationary satellite orbit (GSO) for the fixed-satellite service (FSS), there is widespread concern that the medium may become congested. In order to ensure that each country's access to the radio spectrum from the GSO is adequate in capacity, there is a need for progress in two broad areas of concern to the International Telecommunication Union (ITU). A general improvement is required in some of the characteristics of FSS satellite networks, and there must be improvements in the technical means which are employed for managing the use of the GSO by the FSS. A number of aspects regarding these two areas are discussed in a report from a meeting of the Interim Working Party 4/1 (IWP 4/1). The present article provides a brief review of four of these aspects. Attention is given to satellite antenna radiation patterns, earth station antenna side-lobe response, frequency coordination of FSS networks, and flexibility in the positioning of satellites.

  18. 48 CFR 52.246-4 - Inspection of Services-Fixed-Price.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-Fixed-Price. 52.246-4 Section 52.246-4 Federal Acquisition Regulations System FEDERAL ACQUISITION... Clauses 52.246-4 Inspection of Services—Fixed-Price. As prescribed in 46.304, insert the following clause: Inspection of Services—Fixed-Price (AUG 1996) (a) Definitions. Services, as used in this clause, includes...

  19. 48 CFR 52.246-4 - Inspection of Services-Fixed-Price.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-Fixed-Price. 52.246-4 Section 52.246-4 Federal Acquisition Regulations System FEDERAL ACQUISITION... Clauses 52.246-4 Inspection of Services—Fixed-Price. As prescribed in 46.304, insert the following clause: Inspection of Services—Fixed-Price (AUG 1996) (a) Definitions. Services, as used in this clause, includes...

  20. Applying Semantic Web Services and Wireless Sensor Networks for System Integration

    NASA Astrophysics Data System (ADS)

    Berkenbrock, Gian Ricardo; Hirata, Celso Massaki; de Oliveira Júnior, Frederico Guilherme Álvares; de Oliveira, José Maria Parente

    In environments like factories, buildings, and homes automation services tend to often change during their lifetime. Changes are concerned to business rules, process optimization, cost reduction, and so on. It is important to provide a smooth and straightforward way to deal with these changes so that could be handled in a faster and low cost manner. Some prominent solutions use the flexibility of Wireless Sensor Networks and the meaningful description of Semantic Web Services to provide service integration. In this work, we give an overview of current solutions for machinery integration that combine both technologies as well as a discussion about some perspectives and open issues when applying Wireless Sensor Networks and Semantic Web Services for automation services integration.

  1. Issues in implementing services for a wireless web-enabled digital camera

    NASA Astrophysics Data System (ADS)

    Venkataraman, Shyam; Sampat, Nitin; Fisher, Yoram; Canosa, John; Noel, Nicholas

    2001-05-01

    The competition in the exploding digital photography market has caused vendors to explore new ways to increase their return on investment. A common view among industry analysts is that increasingly it will be services provided by these cameras, and not the cameras themselves, that will provide the revenue stream. These services will be coupled to e- Appliance based Communities. In addition, the rapidly increasing need to upload images to the Internet for photo- finishing services as well as the need to download software upgrades to the camera is driving many camera OEMs to evaluate the benefits of using the wireless web to extend their enterprise systems. Currently, creating a viable e- appliance such as a digital camera coupled with a wireless web service requires more than just a competency in product development. This paper will evaluate the system implications in the deployment of recurring revenue services and enterprise connectivity of a wireless, web-enabled digital camera. These include, among other things, an architectural design approach for services such as device management, synchronization, billing, connectivity, security, etc. Such an evaluation will assist, we hope, anyone designing or connecting a digital camera to the enterprise systems.

  2. 47 CFR 1.1152 - Schedule of annual regulatory fees and filing locations for wireless radio services.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... locations for wireless radio services. 1.1152 Section 1.1152 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Grants by Random Selection Schedule of Statutory Charges and Procedures for Payment § 1.1152 Schedule of annual regulatory fees and filing locations for wireless radio...

  3. 47 CFR 1.1152 - Schedule of annual regulatory fees and filing locations for wireless radio services.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... locations for wireless radio services. 1.1152 Section 1.1152 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Grants by Random Selection Schedule of Statutory Charges and Procedures for Payment § 1.1152 Schedule of annual regulatory fees and filing locations for wireless radio...

  4. 47 CFR 1.1152 - Schedule of annual regulatory fees and filing locations for wireless radio services.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... locations for wireless radio services. 1.1152 Section 1.1152 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Grants by Random Selection Schedule of Statutory Charges and Procedures for Payment § 1.1152 Schedule of annual regulatory fees and filing locations for wireless radio...

  5. 48 CFR 52.246-4 - Inspection of Services-Fixed-Price.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Clauses 52.246-4 Inspection of Services—Fixed-Price. As prescribed in 46.304, insert the following clause: Inspection of Services—Fixed-Price (AUG 1996) (a) Definitions. Services, as used in this clause, includes... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Inspection of...

  6. 47 CFR 25.210 - Technical requirements for space stations in the Fixed-Satellite Service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... space station licensees and outside the primary coverage area to facilitate international frequency... 47 Telecommunication 2 2010-10-01 2010-10-01 false Technical requirements for space stations in... requirements for space stations in the Fixed-Satellite Service. (a) All space stations in the Fixed-Satellite...

  7. 47 CFR 25.210 - Technical requirements for space stations in the Fixed-Satellite Service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... space station licensees and outside the primary coverage area to facilitate international frequency... 47 Telecommunication 2 2011-10-01 2011-10-01 false Technical requirements for space stations in... requirements for space stations in the Fixed-Satellite Service. (a) All space stations in the Fixed-Satellite...

  8. A cost-effective WDM-PON architecture simultaneously supporting wired, wireless and optical VPN services

    NASA Astrophysics Data System (ADS)

    Wu, Yanzhi; Ye, Tong; Zhang, Liang; Hu, Xiaofeng; Li, Xinwan; Su, Yikai

    2011-03-01

    It is believed that next-generation passive optical networks (PONs) are required to provide flexible and various services to users in a cost-effective way. To address this issue, for the first time, this paper proposes and demonstrates a novel wavelength-division-multiplexed PON (WDM-PON) architecture to simultaneously support three types of services: 1) wireless access traffic, 2) optical virtual passive network (VPN) communications, and 3) conventional wired services. In the optical line terminal (OLT), we use two cascaded Mach-Zehnder modulators (MZMs) on each wavelength channel to generate an optical carrier, and produce the wireless and the downstream traffic using the orthogonal modulation technique. In each optical network unit (ONU), the obtained optical carrier is modulated by a single MZM to provide the VPN and upstream communications. Consequently, the light sources in the ONUs are saved and the system cost is reduced. The feasibility of our proposal is experimentally and numerically verified.

  9. Wireless Sensor Network-Based Service Provisioning by a Brokering Platform.

    PubMed

    Guijarro, Luis; Pla, Vicent; Vidal, Jose R; Naldi, Maurizio; Mahmoodi, Toktam

    2017-05-12

    This paper proposes a business model for providing services based on the Internet of Things through a platform that intermediates between human users and Wireless Sensor Networks (WSNs). The platform seeks to maximize its profit through posting both the price charged to each user and the price paid to each WSN. A complete analysis of the profit maximization problem is performed in this paper. We show that the service provider maximizes its profit by incentivizing all users and all Wireless Sensor Infrastructure Providers (WSIPs) to join the platform. This is true not only when the number of users is high, but also when it is moderate, provided that the costs that the users bear do not trespass a cost ceiling. This cost ceiling depends on the number of WSIPs, on the value of the intrinsic value of the service and on the externality that the WSIP has on the user utility.

  10. Managing pricing of QoS for service differentiation in wireless networks

    NASA Astrophysics Data System (ADS)

    Kabranov, Ognian; Nouroozifar, Ali; Dong, Yixin; Makrakis, Dimitrios

    2002-08-01

    In this paper we consider service differentiation in wireless networks using pricing policy. The pricing methodology examined is based on "auctioning" pricing. In the present work, it is applied on IEEE 802.11-based wireless networks. The uplink traffic in an IEEE 802.11 wireless network operating in the PCF mode is considered to be "thin" as the mobile users in the network are subject to power limitations and the biggest volume of traffic occurs on the downlink - from the Base Station to the mobile users. The Base station advertises different levels of Quality of Service (QoS) and the Mobile Users are competing for channel resources by bid requests. Based on the variability of the wireless channel, the amount of the available bandwidth shared between the mobile users changes, the price of the QoS changes as well and the users might change the bids they are offering or change the QoS they request from the Base Station. In the present bidding and pricing scheme, an analytical model for price determination is provided and the results of OPNET based simulations for prove of concept are presented.

  11. Universalizing health services in India: the techno-managerial fix.

    PubMed

    Nayar, K R

    2013-01-01

    The non-universal nature of health services in India can also be the result of many reforms and milestones the health services had passed through since independence. The reform era during the post-nineties is replete with many new trends in organizational strategies which could have led to crises in health services. The salient crises need to be dissected from a larger societal crisis and the specific crises in the health services system. It is evident that non-accessibility and non-availability and the sub-optimal functioning of the primary health centers are perennial issues which could not be addressed by indigenous, imposed or cocktail reforms (such as National Rural Health Mission) and by targeting as these only tinker with the health services. Needless to reiterate that there is a need to address the social dimensions which fall outside the technical sphere of health services. This paper based on an analytical review of relevant literature concludes that any efforts to universalize health and health-care can not only focus on technical components but need to address the larger social determinants and especially the societal crisis, which engender ill-health.

  12. Coordinating Resource Usage through Adaptive Service Provisioning in Wireless Sensor Networks

    NASA Astrophysics Data System (ADS)

    Fok, Chien-Liang; Roman, Gruia-Catalin; Lu, Chenyang

    Wireless sensor networks (WSNs) exhibit high levels of network dynamics and consist of devices with limited energy. This results in the need to coordinate applications not only at the functional level, as is traditionally done, but also in terms of resource utilization. In this paper, we present a middleware that does this using adaptive service provisioning. Novel service binding strategies automatically adapt application behavior when opportunities for energy savings surface, and switch providers when the network topology changes. The former is accomplished by providing limited information about the energy consumption associated with using various services, systematically exploiting opportunities for sharing service invocations, and exploiting the broadcast nature of wireless communication in WSNs. The middleware has been implemented and evaluated on two disparate WSN platforms, the TelosB and Imote2. Empirical results show that adaptive service provisioning can enable energy-aware service binding decisions that result in increased energy efficiency and significantly increase service availability, while imposing minimal additional burden on the application, service, and device developers. Two applications, medical patient monitoring and structural health monitoring, demonstrate the middleware's efficacy.

  13. 48 CFR 2152.216-71 - Fixed price with limited cost redetermination-service charge.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... request, OPM will furnish, during the third quarter of the current contract year, an accounting of the... cost redetermination-service charge. 2152.216-71 Section 2152.216-71 Federal Acquisition Regulations....216-71 Fixed price with limited cost redetermination—service charge. As prescribed in...

  14. Telecommunications: Competition, Capacity, and Costs in the Fixed Satellite Services Industry

    DTIC Science & Technology

    2011-09-01

    majority of these revenues are from transponder agreements, in which customers lease bandwidth capacity directly or indirectly from a satellite operator.3...satellites and lease bandwidth capacity to customers on a wholesale basis. Satellite operators also occasionally provide other services, such as...Acquiring Fixed Satellite Services Bandwidth Satellite operators ● Own and operate satellites ● Lease bandwidth capacity to customers ● Occasionally provide

  15. Ubiquitous Emergency Medical Service System Based on Wireless Biosensors, Traffic Information, and Wireless Communication Technologies: Development and Evaluation

    PubMed Central

    Tan, Tan-Hsu; Gochoo, Munkhjargal; Chen, Yung-Fu; Hu, Jin-Jia; Chiang, John Y.; Chang, Ching-Su; Lee, Ming-Huei; Hsu, Yung-Nian; Hsu, Jiin-Chyr

    2017-01-01

    This study presents a new ubiquitous emergency medical service system (UEMS) that consists of a ubiquitous tele-diagnosis interface and a traffic guiding subsystem. The UEMS addresses unresolved issues of emergency medical services by managing the sensor wires for eliminating inconvenience for both patients and paramedics in an ambulance, providing ubiquitous accessibility of patients’ biosignals in remote areas where the ambulance cannot arrive directly, and offering availability of real-time traffic information which can make the ambulance reach the destination within the shortest time. In the proposed system, patient’s biosignals and real-time video, acquired by wireless biosensors and a webcam, can be simultaneously transmitted to an emergency room for pre-hospital treatment via WiMax/3.5 G networks. Performances of WiMax and 3.5 G, in terms of initialization time, data rate, and average end-to-end delay are evaluated and compared. A driver can choose the route of the shortest time among the suggested routes by Google Maps after inspecting the current traffic conditions based on real-time CCTV camera streams and traffic information. The destination address can be inputted vocally for easiness and safety in driving. A series of field test results validates the feasibility of the proposed system for application in real-life scenarios. PMID:28117724

  16. Ubiquitous Emergency Medical Service System Based on Wireless Biosensors, Traffic Information, and Wireless Communication Technologies: Development and Evaluation.

    PubMed

    Tan, Tan-Hsu; Gochoo, Munkhjargal; Chen, Yung-Fu; Hu, Jin-Jia; Chiang, John Y; Chang, Ching-Su; Lee, Ming-Huei; Hsu, Yung-Nian; Hsu, Jiin-Chyr

    2017-01-21

    This study presents a new ubiquitous emergency medical service system (UEMS) that consists of a ubiquitous tele-diagnosis interface and a traffic guiding subsystem. The UEMS addresses unresolved issues of emergency medical services by managing the sensor wires for eliminating inconvenience for both patients and paramedics in an ambulance, providing ubiquitous accessibility of patients' biosignals in remote areas where the ambulance cannot arrive directly, and offering availability of real-time traffic information which can make the ambulance reach the destination within the shortest time. In the proposed system, patient's biosignals and real-time video, acquired by wireless biosensors and a webcam, can be simultaneously transmitted to an emergency room for pre-hospital treatment via WiMax/3.5 G networks. Performances of WiMax and 3.5 G, in terms of initialization time, data rate, and average end-to-end delay are evaluated and compared. A driver can choose the route of the shortest time among the suggested routes by Google Maps after inspecting the current traffic conditions based on real-time CCTV camera streams and traffic information. The destination address can be inputted vocally for easiness and safety in driving. A series of field test results validates the feasibility of the proposed system for application in real-life scenarios.

  17. Service-Oriented Node Scheduling Scheme for Wireless Sensor Networks Using Markov Random Field Model

    PubMed Central

    Cheng, Hongju; Su, Zhihuang; Lloret, Jaime; Chen, Guolong

    2014-01-01

    Future wireless sensor networks are expected to provide various sensing services and energy efficiency is one of the most important criterions. The node scheduling strategy aims to increase network lifetime by selecting a set of sensor nodes to provide the required sensing services in a periodic manner. In this paper, we are concerned with the service-oriented node scheduling problem to provide multiple sensing services while maximizing the network lifetime. We firstly introduce how to model the data correlation for different services by using Markov Random Field (MRF) model. Secondly, we formulate the service-oriented node scheduling issue into three different problems, namely, the multi-service data denoising problem which aims at minimizing the noise level of sensed data, the representative node selection problem concerning with selecting a number of active nodes while determining the services they provide, and the multi-service node scheduling problem which aims at maximizing the network lifetime. Thirdly, we propose a Multi-service Data Denoising (MDD) algorithm, a novel multi-service Representative node Selection and service Determination (RSD) algorithm, and a novel MRF-based Multi-service Node Scheduling (MMNS) scheme to solve the above three problems respectively. Finally, extensive experiments demonstrate that the proposed scheme efficiently extends the network lifetime. PMID:25384005

  18. Challenges for Wireless Mesh Networks to provide reliable carrier-grade services

    NASA Astrophysics Data System (ADS)

    von Hugo, D.; Bayer, N.

    2011-08-01

    Provision of mobile and wireless services today within a competitive environment and driven by a huge amount of steadily emerging new services and applications is both challenge and chance for radio network operators. Deployment and operation of an infrastructure for mobile and wireless broadband connectivity generally requires planning effort and large investments. A promising approach to reduce expenses for radio access networking is offered by Wireless Mesh Networks (WMNs). Here traditional dedicated backhaul connections to each access point are replaced by wireless multi-hop links between neighbouring access nodes and few gateways to the backbone employing standard radio technology. Such a solution provides at the same time high flexibility in both deployment and the amount of offered capacity and shall reduce overall expenses. On the other hand currently available mesh solutions do not provide carrier grade service quality and reliability and often fail to cope with high traffic load. EU project CARMEN (CARrier grade MEsh Networks) was initiated to incorporate different heterogeneous technologies and new protocols to allow for reliable transmission over "best effort" radio channels, to support a reliable mobility and network management, self-configuration and dynamic resource usage, and thus to offer a permanent or temporary broadband access at high cost efficiency. The contribution provides an overview on preliminary project results with focus on main technical challenges from a research and implementation point of view. Especially impact of mesh topology on the overall system performance in terms of throughput and connection reliability and aspects of a dedicated hybrid mobility management solution will be discussed.

  19. 75 FR 45058 - Operation of Wireless Communications Services in the 2.3 GHz Band; Establishment of Rules and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-02

    ... Communications Service (WCS) bands, while safeguarding from harmful interference satellite radio services, which... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS...- 8610; FCC 10-82] Operation of Wireless Communications Services in the 2.3 GHz Band; Establishment of...

  20. 47 CFR 27.1111 - Relocation of fixed microwave service licensees in the 2110-2150 MHz band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Relocation of fixed microwave service licensees..., 2110-2155 MHz, 2160-2180 MHz Bands Relocation of Incumbents § 27.1111 Relocation of fixed microwave... contain provisions governing the relocation of incumbent fixed microwave service licensees in the 2110...

  1. 47 CFR 27.1111 - Relocation of fixed microwave service licensees in the 2110-2150 MHz band.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Relocation of fixed microwave service licensees..., 2110-2155 MHz, 2160-2180 MHz Bands Relocation of Incumbents § 27.1111 Relocation of fixed microwave... contain provisions governing the relocation of incumbent fixed microwave service licensees in the 2110...

  2. 47 CFR 27.1111 - Relocation of fixed microwave service licensees in the 2110-2150 MHz band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Relocation of fixed microwave service licensees..., 2110-2155 MHz, 2160-2180 MHz Bands Relocation of Incumbents § 27.1111 Relocation of fixed microwave... contain provisions governing the relocation of incumbent fixed microwave service licensees in the...

  3. 47 CFR 27.1111 - Relocation of fixed microwave service licensees in the 2110-2150 MHz band.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Relocation of fixed microwave service licensees... fixed microwave service licensees in the 2110-2150 MHz band. Part 22, subpart E and part 101, subpart B of this chapter contain provisions governing the relocation of incumbent fixed microwave...

  4. DIY-style GIS service in mobile navigation system integrated with web and wireless GIS

    NASA Astrophysics Data System (ADS)

    Yan, Yongbin; Wu, Jianping; Fan, Caiyou; Wang, Minqi; Dai, Sheng

    2007-06-01

    Mobile navigation system based on handheld device can not only provide basic GIS services, but also enable these GIS services to be provided without location limit, to be more instantly interacted between users and devices. However, we still see that most navigation systems have common defects on user experience like limited map format, few map resources, and unable location share. To overcome the above defects, we propose DIY-style GIS service which provide users a more free software environment and allow uses to customize their GIS services. These services include defining geographical coordinate system of maps which helps to hugely enlarge the map source, editing vector feature, related property information and hotlink images, customizing covered area of download map via General Packet Radio Service (GPRS), and sharing users' location information via SMS (Short Message Service) which establishes the communication between users who needs GIS services. The paper introduces the integration of web and wireless GIS service in a mobile navigation system and presents an implementation sample of a DIY-Style GIS service in a mobile navigation system.

  5. Design and Implementation of Secure Area Expansion Scheme for Public Wireless LAN Services

    NASA Astrophysics Data System (ADS)

    Watanabe, Ryu; Tanaka, Toshiaki

    Recently, wireless LAN (WLAN) technology has become a major wireless communication method. The communication bandwidth is increasing and speeds have attained rates exceeding 100 Mbps. Therefore, WLAN technology is regarded as one of the promising communication methods for future networks. In addition, public WLAN connection services can be used in many locations. However, the number of the access points (AP) is insufficient for seamless communication and it cannot be said that users can use the service ubiquitously. An ad-hoc network style connection can be used to expand the coverage area of a public WLAN service. By relaying the user messages among the user nodes, a node can obtain an Internet connection via an AP, even though the node is located outside the AP's direct wireless connection area. Such a coverage area extending technology has many advantages thanks to the feature that no additional infrastructure is required. Therefore, there is a strong demand for this technology as it allows the cost-effective construction of future networks. When a secure ad-hoc routing protocol is used for message exchange in the WLAN service, the message routes are protected from malicious behavior such as route forging and can be maintained appropriately. To do this, however, a new node that wants to join the WLAN service has to obtain information such as the public key certificate and IP address in order to start secure ad-hoc routing. In other words, an initial setup is required for every network node to join the WLAN service properly. Ordinarily, such information should be assigned from the AP. However, new nodes cannot always contact an AP directly. Therefore, there are problems about information delivery in the initial setup of a network node. These problems originate in the multi hop connection based on the ad-hoc routing protocols. In order to realize an expanded area WLAN service, in this paper, the authors propose a secure public key certificate and address provision

  6. Calculation of allowable orbital spacings for the fixed-satellite service

    NASA Technical Reports Server (NTRS)

    Yamamura, Y.; Levis, C. A.

    1985-01-01

    Minimum satellite separations are calculated which satisfy a given carrier-to-interference protection ratio for the Fixed-Satellite Service (FSS) on a single-entry basis, assuming circular antenna beams. The results are presented in the form of universal contour curves, in which antenna-centered angles are the coordinates, and also in terms of the more conventional longitude and latitude separations. It is shown that orbit capacity increases with decreasing service-area size and that, for practical service areas, capacity is increased if the longitude of a satellite does not differ too greatly from that of the service area it serves.

  7. Full-scale validation of wireless hybrid sensor on an in-service highway bridge

    NASA Astrophysics Data System (ADS)

    Jang, Shinae; Dahal, Sushil; Li, Jingcheng

    2013-04-01

    With the rapid development of electrical circuits, Micro electromechanical system (MEMS) and network technology, wireless smart sensor networks (WSSN) have shown significant potential for replacing existing wired SHM systems due to their cost effectiveness and versatility. A few structural systems have been monitored using WSSN measuring acceleration, temperature, wind speed, humidity; however, a multi-scale sensing device which has the capability to measure the displacement has not been yet developed. In the previous paper, a new high-accuracy displacement sensing system was developed combining a high resolution analog displacement sensor and MEMS-based wireless microprocessor platform. Also, the wireless sensor was calibrated in the laboratory to get the high precision displacement data from analog sensor, and its performance was validated to measure simulated thermal expansion of a laboratory bridge structure. This paper expands the validation of the developed system on full-scale experiments to measure both static and dynamic displacement of expansion joints, temperature, and vibration of an in-service highway bridge. A brief visual investigation of bridges, comparison between theoretical and measured thermal expansion are also provided. The developed system showed the capability to measure the displacement with accuracy of 0.00027 in.

  8. Fixed Base Modal Survey of the MPCV Orion European Service Module Structural Test Article

    NASA Technical Reports Server (NTRS)

    Winkel, James P.; Akers, J. C.; Suarez, Vicente J.; Staab, Lucas D.; Napolitano, Kevin L.

    2017-01-01

    Recently, the MPCV Orion European Service Module Structural Test Article (E-STA) underwent sine vibration testing using the multi-axis shaker system at NASA GRC Plum Brook Station Mechanical Vibration Facility (MVF). An innovative approach using measured constraint shapes at the interface of E-STA to the MVF allowed high-quality fixed base modal parameters of the E-STA to be extracted, which have been used to update the E-STA finite element model (FEM), without the need for a traditional fixed base modal survey. This innovative approach provided considerable program cost and test schedule savings. This paper documents this modal survey, which includes the modal pretest analysis sensor selection, the fixed base methodology using measured constraint shapes as virtual references and measured frequency response functions, and post-survey comparison between measured and analysis fixed base modal parameters.

  9. Measurements-based performance evaluation of 3G wireless networks supporting m-health services

    NASA Astrophysics Data System (ADS)

    Wac, Katarzyna E.; Bults, Richard; van Halteren, Aart; Konstantas, Dimitri; Nicola, Victor F.

    2005-01-01

    The emergence of 3G networks gives rise to new mobile services in many different areas of our daily life. Examples of demanding mobile services are mobile-healthcare (i.e. m-health) services allowing the continuous monitoring of a patient"s vital signs. However, a prerequisite for the successful deployment of m-health services are appropriate performance characteristics of transport services offered by an underlying wireless network (e.g. 3G). In this direction, the EU MobiHealth project targeted the evaluation of 3G networks and their ability to support demanding m-health services. The project developed and trialled a patient monitoring system, evaluating at the same time the network's performance. This paper presents measurements based performance evaluation methodology developed and applied to assess network performance from an end-user perspective. In addition, it presents the (selected) speed-related evaluation (best-case scenario) results collected during the project. Our measurements show the dynamicity in the performance of 3G networks and phenomena negatively influencing this performance. Based on the evaluation results, we conclude that in-spite of certain shortcomings of existing 3G networks, they are suitable to support a significant set of m-health services. A set of recommendations provide a road map for both operators and service developers for design and deployment of m-health services.

  10. Measurements-based performance evaluation of 3G wireless networks supporting m-health services

    NASA Astrophysics Data System (ADS)

    Wac, Katarzyna E.; Bults, Richard; van Halteren, Aart; Konstantas, Dimitri; Nicola, Victor F.

    2004-12-01

    The emergence of 3G networks gives rise to new mobile services in many different areas of our daily life. Examples of demanding mobile services are mobile-healthcare (i.e. m-health) services allowing the continuous monitoring of a patient"s vital signs. However, a prerequisite for the successful deployment of m-health services are appropriate performance characteristics of transport services offered by an underlying wireless network (e.g. 3G). In this direction, the EU MobiHealth project targeted the evaluation of 3G networks and their ability to support demanding m-health services. The project developed and trialled a patient monitoring system, evaluating at the same time the network"s performance. This paper presents measurements based performance evaluation methodology developed and applied to assess network performance from an end-user perspective. In addition, it presents the (selected) speed-related evaluation (best-case scenario) results collected during the project. Our measurements show the dynamicity in the performance of 3G networks and phenomena negatively influencing this performance. Based on the evaluation results, we conclude that in-spite of certain shortcomings of existing 3G networks, they are suitable to support a significant set of m-health services. A set of recommendations provide a road map for both operators and service developers for design and deployment of m-health services.

  11. Fixed satellite service frequency allocations and orbit assignment procedures for commercial satellite systems

    NASA Astrophysics Data System (ADS)

    Tycz, Thomas S.

    1990-07-01

    The international regulatory framework which resulted from the 1988 International Telecommunication Union (ITU) Conference on Space Services (ORB-88) and its potential effect on the implementation of US satellite systems are discussed. The impact of several significant results of ORB-88 on the ability of the FCC to assign geostationary satellite orbital positions within the US and to secure international protection for these assignments is reviewed. A table of fixed satellite service frequency allocations in North, Central, and South America is given.

  12. 76 FR 67070 - Operation of Wireless Communications Services in the 2.3 GHz Band; Establishment of Rules and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-31

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS...; FCC 10-82] Operation of Wireless Communications Services in the 2.3 GHz Band; Establishment of Rules and Policies for the Digital Audio Radio Satellite Service in the 2310-2360 MHz Frequency Band AGENCY...

  13. Satellite provided fixed communications services: A forecast of potential domestic demand through the year 2000: Volume 2: Main text

    NASA Technical Reports Server (NTRS)

    Kratochvil, D.; Bowyer, J.; Bhushan, C.; Steinnagel, K.; Kaushal, D.; Al-Kinani, G.

    1983-01-01

    Potential satellite-provided fixed communications services, baseline forecasts, net long haul forecasts, cost analysis, net addressable forecasts, capacity requirements, and satellite system market development are considered.

  14. 47 CFR 2.813 - Transmitters operated in the Instructional Television Fixed Service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Transmitters operated in the Instructional Television Fixed Service. 2.813 Section 2.813 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Marketing of...

  15. 47 CFR 2.813 - Transmitters operated in the Instructional Television Fixed Service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Transmitters operated in the Instructional Television Fixed Service. 2.813 Section 2.813 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Marketing of...

  16. 47 CFR 2.813 - Transmitters operated in the Instructional Television Fixed Service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Transmitters operated in the Instructional Television Fixed Service. 2.813 Section 2.813 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Marketing of...

  17. 47 CFR 2.813 - Transmitters operated in the Instructional Television Fixed Service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Transmitters operated in the Instructional Television Fixed Service. 2.813 Section 2.813 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Marketing of...

  18. 47 CFR 2.813 - Transmitters operated in the Instructional Television Fixed Service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Transmitters operated in the Instructional Television Fixed Service. 2.813 Section 2.813 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Marketing of...

  19. 78 FR 14952 - Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service Geostationary-Orbit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-08

    ... COMMISSION 47 CFR Part 2 Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service... of Earth Stations Aboard Aircraft (ESAA) in the 14.0-14.5 GHz band from secondary to primary and... stations of the FSS on a primary basis in the 11.7-12.2 GHz band (space-to-Earth), on an unprotected...

  20. 78 FR 19172 - Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service Geostationary-Orbit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Parts 2 and 25 Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service... proposed rule that appeared in the Federal Register of March 8, 2013. The document proposed rules for...

  1. 48 CFR 5152.245-9000 - Government property for installation support services (fixed-price contracts).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Government property for installation support services (fixed-price contracts). 5152.245-9000 Section 5152.245-9000 Federal Acquisition Regulations System DEPARTMENT OF THE ARMY ACQUISITION REGULATIONS SOLICITATIONS PROVISIONS AND CONTRACT CLAUSES 5152.245-9000...

  2. 75 FR 52185 - Use of Microwave for Wireless Backhaul; Provision for Additional Flexibility To Broadcast...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-24

    ... Communications Commission 47 CFR Parts 1, 74, and 101 Use of Microwave for Wireless Backhaul; Provision for Additional Flexibility To Broadcast Auxiliary Service and Operational Fixed Microwave Licensees; Proposed...; ] FEDERAL COMMUNICATIONS COMMISSION 47 CFR Parts 1, 74, and 101 Use of Microwave for Wireless...

  3. Wireless Roadside Inspection Phase II Tennessee Commercial Mobile Radio Services Pilot Test Final Report

    SciTech Connect

    Franzese, Oscar; Lascurain, Mary Beth; Capps, Gary J; Siekmann, Adam

    2011-05-01

    The Federal Motor Carrier Safety Administration (FMCSA) Wireless Roadside Inspection (WRI) Program is researching the feasibility and value of electronically assessing truck and bus driver and vehicle safety at least 25 times more often than is possible using only roadside physical inspections. The WRI program is evaluating the potential benefits to both the motor carrier industry and to government. These potential benefits include reduction in accidents, fatalities and injuries on our highways and keeping safe and legal drivers and vehicles moving on the highways. WRI Pilot tests were conducted to prototype, test and demonstrate the feasibility and benefits of electronically collecting safety data message sets from in-service commercial vehicles and performing wireless roadside inspections using three different communication methods. This report summarizes the design, conduct and results of the Tennessee CMRS WRI Pilot Test. The purpose of this Pilot test was to demonstrate the implementation of commercial mobile radio services to electronically request and collect safety data message sets from a limited number of commercial vehicles operating in Tennessee. The results of this test have been used in conjunction with the results of the complimentary pilot tests to support an overall assessment of the feasibility and benefits of WRI in enhancing motor carrier safety (reduction in accidents) due to increased compliance (change in motor carrier and driver behavior) caused by conducting frequent safety inspections electronically, at highway speeds, without delay or need to divert into a weigh station

  4. Broadcasting-satellite and fixed-satellite service considerations after the 1979 World Administrative Radio Conference

    NASA Astrophysics Data System (ADS)

    Akima, H.

    1981-04-01

    The revisions of World Administrative Radio Conference (WARC) of the inter-national radio regulations of the International Telecommunication Union (ITU) including the international table of frequency allocations are reviewed. The revised Radio Regulations will govern internationally the use of the radiofrequency spectrum and the geostationary satellite orbit for the rest of this century. Restricting its scope to the topics related to the broadcasting satellite and fixed satellite services in ITU Region 2 are reported.

  5. Analyzing comprehensive QoS with security constraints for services composition applications in wireless sensor networks.

    PubMed

    Xiong, Naixue; Wu, Zhao; Huang, Yannong; Xu, Degang

    2014-12-01

    Services composition is fundamental to software development in multi-service wireless sensor networks (WSNs). The quality of service (QoS) of services composition applications (SCAs) are confronted with severe challenges due to the open, dynamic, and complex natures of WSNs. Most previous research separated various QoS indices into different fields and studied them individually due to the computational complexity. This approach ignores the mutual influence between these QoS indices, and leads to a non-comprehensive and inaccurate analysis result. The universal generating function (UGF) shows the speediness and precision in QoS analysis. However, only one QoS index at a time can be analyzed by the classic UGF. In order to efficiently analyze the comprehensive QoS of SCAs, this paper proposes an improved UGF technique-vector universal generating function (VUGF)-which considers the relationship between multiple QoS indices, including security, and can simultaneously analyze multiple QoS indices. The numerical examples demonstrate that it can be used for the evaluation of the comprehensive QoS of SCAs subjected to the security constraint in WSNs. Therefore, it can be effectively applied to the optimal design of multi-service WSNs.

  6. Analyzing Comprehensive QoS with Security Constraints for Services Composition Applications in Wireless Sensor Networks

    PubMed Central

    Xiong, Naixue; Wu, Zhao; Huang, Yannong; Xu, Degang

    2014-01-01

    Services composition is fundamental to software development in multi-service wireless sensor networks (WSNs). The quality of service (QoS) of services composition applications (SCAs) are confronted with severe challenges due to the open, dynamic, and complex natures of WSNs. Most previous research separated various QoS indices into different fields and studied them individually due to the computational complexity. This approach ignores the mutual influence between these QoS indices, and leads to a non-comprehensive and inaccurate analysis result. The universal generating function (UGF) shows the speediness and precision in QoS analysis. However, only one QoS index at a time can be analyzed by the classic UGF. In order to efficiently analyze the comprehensive QoS of SCAs, this paper proposes an improved UGF technique—vector universal generating function (VUGF)—which considers the relationship between multiple QoS indices, including security, and can simultaneously analyze multiple QoS indices. The numerical examples demonstrate that it can be used for the evaluation of the comprehensive QoS of SCAs subjected to the security constraint in WSNs. Therefore, it can be effectively applied to the optimal design of multi-service WSNs. PMID:25470488

  7. Congestion Prediction Modeling for Quality of Service Improvement in Wireless Sensor Networks

    PubMed Central

    Lee, Ga-Won; Lee, Sung-Young; Huh, Eui-Nam

    2014-01-01

    Information technology (IT) is pushing ahead with drastic reforms of modern life for improvement of human welfare. Objects constitute “Information Networks” through smart, self-regulated information gathering that also recognizes and controls current information states in Wireless Sensor Networks (WSNs). Information observed from sensor networks in real-time is used to increase quality of life (QoL) in various industries and daily life. One of the key challenges of the WSNs is how to achieve lossless data transmission. Although nowadays sensor nodes have enhanced capacities, it is hard to assure lossless and reliable end-to-end data transmission in WSNs due to the unstable wireless links and low hard ware resources to satisfy high quality of service (QoS) requirements. We propose a node and path traffic prediction model to predict and minimize the congestion. This solution includes prediction of packet generation due to network congestion from both periodic and event data generation. Simulation using NS-2 and Matlab is used to demonstrate the effectiveness of the proposed solution. PMID:24784035

  8. TinyOS-based quality of service management in wireless sensor networks

    USGS Publications Warehouse

    Peterson, N.; Anusuya-Rangappa, L.; Shirazi, B.A.; Huang, R.; Song, W.-Z.; Miceli, M.; McBride, D.; Hurson, A.; LaHusen, R.

    2009-01-01

    Previously the cost and extremely limited capabilities of sensors prohibited Quality of Service (QoS) implementations in wireless sensor networks. With advances in technology, sensors are becoming significantly less expensive and the increases in computational and storage capabilities are opening the door for new, sophisticated algorithms to be implemented. Newer sensor network applications require higher data rates with more stringent priority requirements. We introduce a dynamic scheduling algorithm to improve bandwidth for high priority data in sensor networks, called Tiny-DWFQ. Our Tiny-Dynamic Weighted Fair Queuing scheduling algorithm allows for dynamic QoS for prioritized communications by continually adjusting the treatment of communication packages according to their priorities and the current level of network congestion. For performance evaluation, we tested Tiny-DWFQ, Tiny-WFQ (traditional WFQ algorithm implemented in TinyOS), and FIFO queues on an Imote2-based wireless sensor network and report their throughput and packet loss. Our results show that Tiny-DWFQ performs better in all test cases. ?? 2009 IEEE.

  9. Congestion prediction modeling for quality of service improvement in wireless sensor networks.

    PubMed

    Lee, Ga-Won; Lee, Sung-Young; Huh, Eui-Nam

    2014-04-30

    Information technology (IT) is pushing ahead with drastic reforms of modern life for improvement of human welfare. Objects constitute "Information Networks" through smart, self-regulated information gathering that also recognizes and controls current information states in Wireless Sensor Networks (WSNs). Information observed from sensor networks in real-time is used to increase quality of life (QoL) in various industries and daily life. One of the key challenges of the WSNs is how to achieve lossless data transmission. Although nowadays sensor nodes have enhanced capacities, it is hard to assure lossless and reliable end-to-end data transmission in WSNs due to the unstable wireless links and low hard ware resources to satisfy high quality of service (QoS) requirements. We propose a node and path traffic prediction model to predict and minimize the congestion. This solution includes prediction of packet generation due to network congestion from both periodic and event data generation. Simulation using NS-2 and Matlab is used to demonstrate the effectiveness of the proposed solution.

  10. Flexible quality of service model for wireless body area sensor networks.

    PubMed

    Liao, Yangzhe; Leeson, Mark S; Higgins, Matthew D

    2016-03-01

    Wireless body area sensor networks (WBASNs) are becoming an increasingly significant breakthrough technology for smart healthcare systems, enabling improved clinical decision-making in daily medical care. Recently, radio frequency ultra-wideband technology has developed substantially for physiological signal monitoring due to its advantages such as low-power consumption, high transmission data rate, and miniature antenna size. Applications of future ubiquitous healthcare systems offer the prospect of collecting human vital signs, early detection of abnormal medical conditions, real-time healthcare data transmission and remote telemedicine support. However, due to the technical constraints of sensor batteries, the supply of power is a major bottleneck for healthcare system design. Moreover, medium access control (MAC) needs to support reliable transmission links that allow sensors to transmit data safely and stably. In this Letter, the authors provide a flexible quality of service model for ad hoc networks that can support fast data transmission, adaptive schedule MAC control, and energy efficient ubiquitous WBASN networks. Results show that the proposed multi-hop communication ad hoc network model can balance information packet collisions and power consumption. Additionally, wireless communications link in WBASNs can effectively overcome multi-user interference and offer high transmission data rates for healthcare systems.

  11. An Enhanced Lightweight Anonymous Authentication Scheme for a Scalable Localization Roaming Service in Wireless Sensor Networks.

    PubMed

    Chung, Youngseok; Choi, Seokjin; Lee, Youngsook; Park, Namje; Won, Dongho

    2016-10-07

    More security concerns and complicated requirements arise in wireless sensor networks than in wired networks, due to the vulnerability caused by their openness. To address this vulnerability, anonymous authentication is an essential security mechanism for preserving privacy and providing security. Over recent years, various anonymous authentication schemes have been proposed. Most of them reveal both strengths and weaknesses in terms of security and efficiency. Recently, Farash et al. proposed a lightweight anonymous authentication scheme in ubiquitous networks, which remedies the security faults of previous schemes. However, their scheme still suffers from certain weaknesses. In this paper, we prove that Farash et al.'s scheme fails to provide anonymity, authentication, or password replacement. In addition, we propose an enhanced scheme that provides efficiency, as well as anonymity and security. Considering the limited capability of sensor nodes, we utilize only low-cost functions, such as one-way hash functions and bit-wise exclusive-OR operations. The security and lightness of the proposed scheme mean that it can be applied to roaming service in localized domains of wireless sensor networks, to provide anonymous authentication of sensor nodes.

  12. An Enhanced Lightweight Anonymous Authentication Scheme for a Scalable Localization Roaming Service in Wireless Sensor Networks

    PubMed Central

    Chung, Youngseok; Choi, Seokjin; Lee, Youngsook; Park, Namje; Won, Dongho

    2016-01-01

    More security concerns and complicated requirements arise in wireless sensor networks than in wired networks, due to the vulnerability caused by their openness. To address this vulnerability, anonymous authentication is an essential security mechanism for preserving privacy and providing security. Over recent years, various anonymous authentication schemes have been proposed. Most of them reveal both strengths and weaknesses in terms of security and efficiency. Recently, Farash et al. proposed a lightweight anonymous authentication scheme in ubiquitous networks, which remedies the security faults of previous schemes. However, their scheme still suffers from certain weaknesses. In this paper, we prove that Farash et al.’s scheme fails to provide anonymity, authentication, or password replacement. In addition, we propose an enhanced scheme that provides efficiency, as well as anonymity and security. Considering the limited capability of sensor nodes, we utilize only low-cost functions, such as one-way hash functions and bit-wise exclusive-OR operations. The security and lightness of the proposed scheme mean that it can be applied to roaming service in localized domains of wireless sensor networks, to provide anonymous authentication of sensor nodes. PMID:27739417

  13. 78 FR 70237 - Operation of Wireless Communications Services in the 2.3 GHz Band; Establishment of Rules and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-25

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS...-130] Operation of Wireless Communications Services in the 2.3 GHz Band; Establishment of Rules and... Communications Commission. ACTION: Final rule; announcement of effective date. SUMMARY: In this document,...

  14. 76 FR 1126 - Wireless E911 Location Accuracy Requirements; E911 Requirements for IP-Enabled Service Providers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-07

    ... COMMISSION 47 CFR Part 20 Wireless E911 Location Accuracy Requirements; E911 Requirements for IP-Enabled... comment on how to further improve the location capability of 911 and E911 services for existing and new... of Next Generation 911 (NG911) networks. The E911 Location Accuracy FNPRM and NOI was published in...

  15. SOMM: A new service oriented middleware for generic wireless multimedia sensor networks based on code mobility.

    PubMed

    Faghih, Mohammad Mehdi; Moghaddam, Mohsen Ebrahimi

    2011-01-01

    Although much research in the area of Wireless Multimedia Sensor Networks (WMSNs) has been done in recent years, the programming of sensor nodes is still time-consuming and tedious. It requires expertise in low-level programming, mainly because of the use of resource constrained hardware and also the low level API provided by current operating systems. The code of the resulting systems has typically no clear separation between application and system logic. This minimizes the possibility of reusing code and often leads to the necessity of major changes when the underlying platform is changed. In this paper, we present a service oriented middleware named SOMM to support application development for WMSNs. The main goal of SOMM is to enable the development of modifiable and scalable WMSN applications. A network which uses the SOMM is capable of providing multiple services to multiple clients at the same time with the specified Quality of Service (QoS). SOMM uses a virtual machine with the ability to support mobile agents. Services in SOMM are provided by mobile agents and SOMM also provides a t space on each node which agents can use to communicate with each other.

  16. 78 FR 6217 - Facilitating the Use of Microwave for Wireless Backhaul and Other Uses and Providing Additional...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-30

    ... COMMISSION 47 CFR Part 74 Facilitating the Use of Microwave for Wireless Backhaul and Other Uses and Providing Additional Flexibility To Broadcast Auxiliary Service and Operational Fixed Microwave Licensees... and Order (Order), Facilitating the use of Microwave for Wireless Backhaul and Other Uses...

  17. Performance and Challenges of Service-Oriented Architecture for Wireless Sensor Networks.

    PubMed

    Alshinina, Remah; Elleithy, Khaled

    2017-03-08

    Wireless Sensor Networks (WSNs) have become essential components for a variety of environmental, surveillance, military, traffic control, and healthcare applications. These applications face critical challenges such as communication, security, power consumption, data aggregation, heterogeneities of sensor hardware, and Quality of Service (QoS) issues. Service-Oriented Architecture (SOA) is a software architecture that can be integrated with WSN applications to address those challenges. The SOA middleware bridges the gap between the high-level requirements of different applications and the hardware constraints of WSNs. This survey explores state-of-the-art approaches based on SOA and Service-Oriented Middleware (SOM) architecture that provide solutions for WSN challenges. The categories of this paper are based on approaches of SOA with and without middleware for WSNs. Additionally, features of SOA and middleware architectures for WSNs are compared to achieve more robust and efficient network performance. Design issues of SOA middleware for WSNs and its characteristics are also highlighted. The paper concludes with future research directions in SOM architecture to meet all requirements of emerging application of WSNs.

  18. Optimizing the Reliability and Performance of Service Composition Applications with Fault Tolerance in Wireless Sensor Networks

    PubMed Central

    Wu, Zhao; Xiong, Naixue; Huang, Yannong; Xu, Degang; Hu, Chunyang

    2015-01-01

    The services composition technology provides flexible methods for building service composition applications (SCAs) in wireless sensor networks (WSNs). The high reliability and high performance of SCAs help services composition technology promote the practical application of WSNs. The optimization methods for reliability and performance used for traditional software systems are mostly based on the instantiations of software components, which are inapplicable and inefficient in the ever-changing SCAs in WSNs. In this paper, we consider the SCAs with fault tolerance in WSNs. Based on a Universal Generating Function (UGF) we propose a reliability and performance model of SCAs in WSNs, which generalizes a redundancy optimization problem to a multi-state system. Based on this model, an efficient optimization algorithm for reliability and performance of SCAs in WSNs is developed based on a Genetic Algorithm (GA) to find the optimal structure of SCAs with fault-tolerance in WSNs. In order to examine the feasibility of our algorithm, we have evaluated the performance. Furthermore, the interrelationships between the reliability, performance and cost are investigated. In addition, a distinct approach to determine the most suitable parameters in the suggested algorithm is proposed. PMID:26561818

  19. Performance and Challenges of Service-Oriented Architecture for Wireless Sensor Networks

    PubMed Central

    Alshinina, Remah; Elleithy, Khaled

    2017-01-01

    Wireless Sensor Networks (WSNs) have become essential components for a variety of environmental, surveillance, military, traffic control, and healthcare applications. These applications face critical challenges such as communication, security, power consumption, data aggregation, heterogeneities of sensor hardware, and Quality of Service (QoS) issues. Service-Oriented Architecture (SOA) is a software architecture that can be integrated with WSN applications to address those challenges. The SOA middleware bridges the gap between the high-level requirements of different applications and the hardware constraints of WSNs. This survey explores state-of-the-art approaches based on SOA and Service-Oriented Middleware (SOM) architecture that provide solutions for WSN challenges. The categories of this paper are based on approaches of SOA with and without middleware for WSNs. Additionally, features of SOA and middleware architectures for WSNs are compared to achieve more robust and efficient network performance. Design issues of SOA middleware for WSNs and its characteristics are also highlighted. The paper concludes with future research directions in SOM architecture to meet all requirements of emerging application of WSNs. PMID:28282896

  20. Technical basis of the ITU allotment plan for the fixed satellite service in the expansion bands

    NASA Astrophysics Data System (ADS)

    Sahay, V.; Rawat, V.

    In May 1988, the World Administrative Radio Conference (WARC) for space services developed an allotment plan for certain fixed satellite service (FSS) bands. This paper will describe in detail the technical basis for the allotment plan, the reasoning behind the technical annexes associated with it, and some of the technical issues for implementation. The plan identifies orbital positions, service areas, and technical parameters for the various systems. The plan was developed using a set of standardized parameters based on typical systems. Flexibility to implement other parameters was achieved by defining generalized parameters, which are related to the interference causing and accepting capabilities of this typical set. Thus, implementation flexibility within defined limits is possible without coordination. If these limits are exceeded, implementation is still possible provided agreement is reached with those administrations affected as defined in the Final Acts. It is noted that sharing conditions with other services continue unchanged as in the current International Telecommunication Union (ITU) Radio Regulations. The criteria have provided considerable flexibility for Canadian usage. They did not affect the relative priority of services sharing the band, and coordination with terrestrial service will continue to be required.

  1. The new international regulatory regime for the fixed satellite service: Opportunities and constraints for Canada

    NASA Astrophysics Data System (ADS)

    Amero, R. G.; Carew, A. V.; Ducharme, E. D.; McKay, A. D.

    Frequencies used by Canadian satellite systems are coordinated internationally under the International Telecommunication Union (ITU) Radio Regulations. Fundamental changes in these regulations were made by the recent World Administrative Radio Conference (WARC) on the use of the geostationary satellite orbit and planning of space services utilizing it. WARC developed a new regulatory regime for the 6/4 GHz and 14/12 GHz bands currently used by Telesat Canada, and a different one involving a world a priori allotment plan for those portions of the 6/4 GHz and 13/10-11 GHz bands made available to the Fixed Satellite Service by the ITU General WARC in 1979. While these new regulations have been streamlined in some areas, overall the body of regulations pertaining to the fixed satellite service is much more complex, mainly as a result of demands by developing countries to have more assured access to these frequency bands and their wish to see portions of the orbit / spectrum resource reserved for their future use. The major features of these new regulatory procedures are described and the impact on the operation of current and future satellites will be identified.

  2. 48 CFR 1552.216-73 - Fixed rates for services-indefinite delivery/indefinite quantity contract.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false Fixed rates for services... Regulations System ENVIRONMENTAL PROTECTION AGENCY CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 1552.216-73 Fixed rates for services—indefinite...

  3. 48 CFR 1552.216-73 - Fixed rates for services-indefinite delivery/indefinite quantity contract.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Fixed rates for services... Regulations System ENVIRONMENTAL PROTECTION AGENCY CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 1552.216-73 Fixed rates for services—indefinite...

  4. Dynamic quality of service differentiation using fixed code weight in optical CDMA networks

    NASA Astrophysics Data System (ADS)

    Kakaee, Majid H.; Essa, Shawnim I.; Abd, Thanaa H.; Seyedzadeh, Saleh

    2015-11-01

    The emergence of network-driven applications, such as internet, video conferencing, and online gaming, brings in the need for a network the environments with capability of providing diverse Quality of Services (QoS). In this paper, a new code family of novel spreading sequences, called a Multi-Service (MS) code, has been constructed to support multiple services in Optical- Code Division Multiple Access (CDMA) system. The proposed method uses fixed weight for all services, however reducing the interfering codewords for the users requiring higher QoS. The performance of the proposed code is demonstrated using mathematical analysis. It shown that the total number of served users with satisfactory BER of 10-9 using NB=2 is 82, while they are only 36 and 10 when NB=3 and 4 respectively. The developed MS code is compared with variable-weight codes such as Variable Weight-Khazani Syed (VW-KS) and Multi-Weight-Random Diagonal (MW-RD). Different numbers of basic users (NB) are used to support triple-play services (audio, data and video) with different QoS requirements. Furthermore, reference to the BER of 10-12, 10-9, and 10-3 for video, data and audio, respectively, the system can support up to 45 total users. Hence, results show that the technique can clearly provide a relative QoS differentiation with lower value of basic users can support larger number of subscribers as well as better performance in terms of acceptable BER of 10-9 at fixed code weight.

  5. 47 CFR 27.1111 - Relocation of fixed microwave service licensees in the 2110-2150 and 2160-2200 MHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Relocation of fixed microwave service licensees... Incumbents § 27.1111 Relocation of fixed microwave service licensees in the 2110-2150 and 2160-2200 MHz bands... of incumbent fixed microwave service licensees in the 2110-2150 MHz and 2160-2200 MHz bands. [79...

  6. A new paradigm for the construction and service of fixed prosthodontics.

    PubMed

    Westerman, R D

    1999-06-01

    Some of the most disheartening things that can happen to restorative dentists is to be faced with problems, complications, and failures in their own fixed prosthodontics. A highly advantageous technique for removing existing restorations and creating removable cement-retained fixed prosthodontics has been described. In the history of crown and bridge prosthodontics, there has not been a proven precision technique to remove these restorations, with the exception of screw-retained implant prostheses, which exhibit many disadvantages. This new paradigm provides a new dimension to the practice of dentistry and allows for the repair, service, and maintenance of restorations in ways that have never been done in the past. Removing crowns and fixed bridges can be learned like any other dental skill, such as endodontics or taking accurate impressions. Skill and confidence comes when the technique has been performed on a large variety of cases. Being able to quickly and easily remove these restorations can certainly be rewarding and reduce a lot of stress.

  7. Massive Access Control Aided by Knowledge-Extraction for Co-Existing Periodic and Random Services over Wireless Clinical Networks.

    PubMed

    Du, Qinghe; Zhao, Weidong; Li, Weimin; Zhang, Xuelin; Sun, Bo; Song, Houbing; Ren, Pinyi; Sun, Li; Wang, Yichen

    2016-07-01

    The prosperity of e-health is boosted by fast development of medical devices with wireless communications capability such as wearable devices, tiny sensors, monitoring equipments, etc., which are randomly distributed in clinic environments. The drastically-increasing population of such devices imposes new challenges on the limited wireless resources. To relieve this problem, key knowledge needs to be extracted from massive connection attempts dispersed in the air towards efficient access control. In this paper, a hybrid periodic-random massive access (HPRMA) scheme for wireless clinical networks employing ultra-narrow band (UNB) techniques is proposed. In particular, the proposed scheme towards accommodating a large population of devices include the following new features. On one hand, it can dynamically adjust the resource allocated for coexisting periodic and random services based on the traffic load learned from signal collision status. On the other hand, the resource allocation within periodic services is thoroughly designed to simultaneously align with the timing requests of differentiated services. Abundant simulation results are also presented to demonstrate the superiority of the proposed HPRMA scheme over baseline schemes including time-division multiple access (TDMA) and random access approach, in terms of channel utilization efficiency, packet drop ratio, etc., for the support of massive devices' services.

  8. Multi-service small-cell cloud wired/wireless access network based on tunable optical frequency comb

    NASA Astrophysics Data System (ADS)

    Xiang, Yu; Zhou, Kun; Yang, Liu; Pan, Lei; Liao, Zhen-wan; Zhang, Qiang

    2015-11-01

    In this paper, we demonstrate a novel multi-service wired/wireless integrated access architecture of cloud radio access network (C-RAN) based on radio-over-fiber passive optical network (RoF-PON) system, which utilizes scalable multiple- frequency millimeter-wave (MF-MMW) generation based on tunable optical frequency comb (TOFC). In the baseband unit (BBU) pool, the generated optical comb lines are modulated into wired, RoF and WiFi/WiMAX signals, respectively. The multi-frequency RoF signals are generated by beating the optical comb line pairs in the small cell. The WiFi/WiMAX signals are demodulated after passing through the band pass filter (BPF) and band stop filter (BSF), respectively, whereas the wired signal can be received directly. The feasibility and scalability of the proposed multi-service wired/wireless integrated C-RAN are confirmed by the simulations.

  9. PIYAS-Proceeding to Intelligent Service Oriented Memory Allocation for Flash Based Data Centric Sensor Devices in Wireless Sensor Networks

    PubMed Central

    Rizvi, Sanam Shahla; Chung, Tae-Sun

    2010-01-01

    Flash memory has become a more widespread storage medium for modern wireless devices because of its effective characteristics like non-volatility, small size, light weight, fast access speed, shock resistance, high reliability and low power consumption. Sensor nodes are highly resource constrained in terms of limited processing speed, runtime memory, persistent storage, communication bandwidth and finite energy. Therefore, for wireless sensor networks supporting sense, store, merge and send schemes, an efficient and reliable file system is highly required with consideration of sensor node constraints. In this paper, we propose a novel log structured external NAND flash memory based file system, called Proceeding to Intelligent service oriented memorY Allocation for flash based data centric Sensor devices in wireless sensor networks (PIYAS). This is the extended version of our previously proposed PIYA [1]. The main goals of the PIYAS scheme are to achieve instant mounting and reduced SRAM space by keeping memory mapping information to a very low size of and to provide high query response throughput by allocation of memory to the sensor data by network business rules. The scheme intelligently samples and stores the raw data and provides high in-network data availability by keeping the aggregate data for a longer period of time than any other scheme has done before. We propose effective garbage collection and wear-leveling schemes as well. The experimental results show that PIYAS is an optimized memory management scheme allowing high performance for wireless sensor networks. PMID:22315541

  10. PIYAS-proceeding to intelligent service oriented memory allocation for flash based data centric sensor devices in wireless sensor networks.

    PubMed

    Rizvi, Sanam Shahla; Chung, Tae-Sun

    2010-01-01

    Flash memory has become a more widespread storage medium for modern wireless devices because of its effective characteristics like non-volatility, small size, light weight, fast access speed, shock resistance, high reliability and low power consumption. Sensor nodes are highly resource constrained in terms of limited processing speed, runtime memory, persistent storage, communication bandwidth and finite energy. Therefore, for wireless sensor networks supporting sense, store, merge and send schemes, an efficient and reliable file system is highly required with consideration of sensor node constraints. In this paper, we propose a novel log structured external NAND flash memory based file system, called Proceeding to Intelligent service oriented memorY Allocation for flash based data centric Sensor devices in wireless sensor networks (PIYAS). This is the extended version of our previously proposed PIYA [1]. The main goals of the PIYAS scheme are to achieve instant mounting and reduced SRAM space by keeping memory mapping information to a very low size of and to provide high query response throughput by allocation of memory to the sensor data by network business rules. The scheme intelligently samples and stores the raw data and provides high in-network data availability by keeping the aggregate data for a longer period of time than any other scheme has done before. We propose effective garbage collection and wear-leveling schemes as well. The experimental results show that PIYAS is an optimized memory management scheme allowing high performance for wireless sensor networks.

  11. 47 CFR 25.145 - Licensing provisions for the Fixed-Satellite Service in the 20/30 GHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Licensing provisions for the Fixed-Satellite Service in the 20/30 GHz bands. 25.145 Section 25.145 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25...

  12. 76 FR 32901 - The Provision of Fixed and Mobile Broadband Access, Educational and Other Advanced Services in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-07

    ... subscriber station and base station with a typical cell radius of 3 to 10 kilometers. WiMAX can support fixed... satellite service (MSS) system with the downlink (satellite to mobile earth stations) in the 2483.5-2500 MHz... of 6 MHz or the actual emission bandwidth as defined in Sec. 27.53(m)(6). Mobile Satellite Service...

  13. 47 CFR 25.145 - Licensing conditions for the Fixed-Satellite Service in the 20/30 GHz bands.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25... covering a specified number of space stations to operate in a specified number of orbital planes. (c) In... applicant for a space station in the fixed-satellite service operating in the 20/30 GHz band if that...

  14. 47 CFR 25.145 - Licensing provisions for the Fixed-Satellite Service in the 20/30 GHz bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25... covering a specified number of space stations to operate in a specified number of orbital planes. (c) In... applicant for a space station in the Fixed-Satellite Service operating in the 20/30 GHz band if that...

  15. 47 CFR 25.145 - Licensing conditions for the Fixed-Satellite Service in the 20/30 GHz bands.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25... covering a specified number of space stations to operate in a specified number of orbital planes. (c) In... applicant for a space station in the fixed-satellite service operating in the 20/30 GHz band if that...

  16. 47 CFR 25.145 - Licensing conditions for the Fixed-Satellite Service in the 20/30 GHz bands.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25... covering a specified number of space stations to operate in a specified number of orbital planes. (c) In... applicant for a space station in the fixed-satellite service operating in the 20/30 GHz band if that...

  17. STS-105 and Expedition Three crews pose together for photo on Fixed Service Structure

    NASA Technical Reports Server (NTRS)

    2001-01-01

    KENNEDY SPACE CENTER, Fla. -- The STS-105 crew poses on the Fixed Service Structure at Launch Pad 39A. From left are Mission Specialist Patrick Forrester, Commander Scott Horowitz, Pilot Rick Sturckow and Mission Specialist Dan Barry. The STS-105 and Expedition Three crews are at Kennedy Space Center participating in a Terminal Countdown Demonstration Test, a dress rehearsal for launch. The activities include emergency egress training, a simulated launch countdown and familiarization with the payload. Mission STS-105 will be transporting the Expedition Three crew, several payloads and scientific experiments to the International Space Station aboard Space Shuttle Discovery. The Expedition Two crew members currently on the Station will return to Earth on Discovery. The mission is scheduled to launch no earlier than Aug. 9, 2001.

  18. The possibilities for mobile and fixed services up to the 20/30 GHz frequency bands

    NASA Technical Reports Server (NTRS)

    Hughes, Clifford D.; Feliciani, F.; Spiller, J.

    1993-01-01

    Satellite Communications and broadcasting is presently in a period of considerable change. In the fixed service there is strong competition from terrestrial fiber optic systems which have virtually arrested the growth of the traditional satellite market for long distance high capacity communications. The satellite has however made considerable progress in areas where it has unique advantages; for example, in point to multipoint (broadcasting), multipoint to point (data collection) and generally in small terminal system applications where flexibility of deployment coupled with ease of installation are of importance. In the mobile service, in addition to the already established geostationary systems, there are numerous proposals for HEO, MEO and LEO systems. There are also several new frequency allocations as a result of the WARC 92 to be taken into account. At one extreme there are researchers working on Ka band 20/30 GHz mobile systems and there are other groups who foresee no future above the L-band frequency allocations. Amongst all these inputs it is difficult to see the direction in which development activities both for satellites and for earth segment should be focused. However, as an aid to understanding, this paper seeks to find some underlying relationships and to clarify some of the variables.

  19. Reimbursement patterns in a hospital-based fixed-wing aeromedical service.

    PubMed

    Lindbeck, G H

    1993-11-01

    Reimbursement, expressed as a percentage of total charges recovered, was examined for inpatients transported by a university hospital-based, dedicated, fixed-wing aeromedical service between July 1, 1988 and June 30, 1990. A total of 410 patients were transported; account information was available for 404 patients (98%). Patients transported from in-state institutions (n = 174) had a hospital reimbursement rate of 53.3%, whereas the flight program recovered 46.1% of transportation charges. Patients transported from out-of-state institutions (n = 150) had a hospital reimbursement rate of 51.3%, whereas the flight program recovered 69.3% of charges. More patients referred from in-state sources were covered by Medicaid than from out-of-state sources (31% vs 11%), and less were covered by Medicare (17% vs 30%). Reimbursement for hospital charges was low for patients covered by Medicaid (44% for in-state and 16% for out-of-state), and Medicaid reimbursed no flight charges for either in-state or out-of-state patients. The flight program recovered 86.7% of charges for "triangle" flights, which transported patients between two hospitals other than the sponsoring institution (n = 80). The overall hospital reimbursement rate for inpatients was 70% during the study period. The flight program recovered 53.7% of its operating costs from payment of charges for transport services. Aeromedically transported patients may represent a financial "high-risk" group of patients for the sponsoring institution.

  20. Generalized technical parameters in the ITU allotment plan for the fixed satellite service

    NASA Astrophysics Data System (ADS)

    Sahay, Vishnu

    The paper discusses the technical basis for the approach used at the WARC ORB-2 to permit the development of an allotment plan for the fixed satellite service which would allow systems to be implemented without the need for detailed coordination. It is shown that a unique characteristic exists among power-limited systems such as satellites that makes the desired kind of orbit planning possible. This feature is referred to as the A,B,C,D generalized parameters concept. In satellite systems the C/I ratio protection criteria for various combinations of service vary over a very wide range, 8-50 dB. However, due to power limitations on the satellites, the ratio of the power per unit bandwidth of the wanted and unwanted signals stays within the relatively narrow range of 26-30 dB. Thus, a plan based on a criterion in this range, e.g., 30 dB, if accompanied by a technical requirement for the system designer to observe the calculated 'average power density', would then be essentially precoordinated.

  1. The possibilities for mobile and fixed services up to the 20/30 GHz frequency bands

    NASA Astrophysics Data System (ADS)

    Hughes, Clifford D.; Feliciani, F.; Spiller, J.

    Satellite Communications and broadcasting is presently in a period of considerable change. In the fixed service there is strong competition from terrestrial fiber optic systems which have virtually arrested the growth of the traditional satellite market for long distance high capacity communications. The satellite has however made considerable progress in areas where it has unique advantages; for example, in point to multipoint (broadcasting), multipoint to point (data collection) and generally in small terminal system applications where flexibility of deployment coupled with ease of installation are of importance. In the mobile service, in addition to the already established geostationary systems, there are numerous proposals for HEO, MEO and LEO systems. There are also several new frequency allocations as a result of the WARC 92 to be taken into account. At one extreme there are researchers working on Ka band 20/30 GHz mobile systems and there are other groups who foresee no future above the L-band frequency allocations. Amongst all these inputs it is difficult to see the direction in which development activities both for satellites and for earth segment should be focused. However, as an aid to understanding, this paper seeks to find some underlying relationships and to clarify some of the variables.

  2. 77 FR 73956 - Facilitating the Use of Microwave for Wireless Backhaul and Other Uses and Providing Additional...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-12

    ... COMMISSION 47 CFR Part 101 Facilitating the Use of Microwave for Wireless Backhaul and Other Uses and Providing Additional Flexibility to Broadcast Auxiliary Service and Operational Fixed Microwave Licensees... correcting amendments: PART 101--FIXED MICROWAVE 0 1. The authority citation for part 101 continues to read...

  3. Field testing of Martlet wireless sensing system on an in-service pre-stressed concrete highway bridge

    NASA Astrophysics Data System (ADS)

    Liu, Xi; Dong, Xinjun; Wang, Yang

    2016-04-01

    In structural sensing applications, wireless sensing systems have drawn great interest owing to faster installation process and lower system cost compared to the traditional cabled systems. As a new-generation wireless sensing system, Martlet features high-speed data acquisition and extensible layout, which allows easy interfacing with various types of sensors. This paper presents a field test of the Martlet sensing system installed at an in-service pre-stressed concrete highway bridge on SR113 over Dry Creek in Bartow County, Georgia. Four types of sensors are interfaced with Martlet in this test, including accelerometers, strain gages, strain transducers and magnetostrictive displacement sensors. In addition, thermocouples are used to monitor the temperature change of the bridge through the day. The acceleration, strain and displacement response of the bridge due to traffic and ambient excitations are measured. To obtain the modal properties of the bridge, hammer impact tests are also performed. The results from the field test demonstrate the reliability of the Martlet wireless sensing system. In addition, detailed modal properties of the bridge are extracted from the acceleration data collected in the test.

  4. Map as a Service: A Framework for Visualising and Maximising Information Return from Multi-Modal Wireless Sensor Networks

    PubMed Central

    Hammoudeh, Mohammad; Newman, Robert; Dennett, Christopher; Mount, Sarah; Aldabbas, Omar

    2015-01-01

    This paper presents a distributed information extraction and visualisation service, called the mapping service, for maximising information return from large-scale wireless sensor networks. Such a service would greatly simplify the production of higher-level, information-rich, representations suitable for informing other network services and the delivery of field information visualisations. The mapping service utilises a blend of inductive and deductive models to map sense data accurately using externally available knowledge. It utilises the special characteristics of the application domain to render visualisations in a map format that are a precise reflection of the concrete reality. This service is suitable for visualising an arbitrary number of sense modalities. It is capable of visualising from multiple independent types of the sense data to overcome the limitations of generating visualisations from a single type of sense modality. Furthermore, the mapping service responds dynamically to changes in the environmental conditions, which may affect the visualisation performance by continuously updating the application domain model in a distributed manner. Finally, a distributed self-adaptation function is proposed with the goal of saving more power and generating more accurate data visualisation. We conduct comprehensive experimentation to evaluate the performance of our mapping service and show that it achieves low communication overhead, produces maps of high fidelity, and further minimises the mapping predictive error dynamically through integrating the application domain model in the mapping service. PMID:26378539

  5. Map as a Service: A Framework for Visualising and Maximising Information Return from Multi-ModalWireless Sensor Networks.

    PubMed

    Hammoudeh, Mohammad; Newman, Robert; Dennett, Christopher; Mount, Sarah; Aldabbas, Omar

    2015-09-11

    This paper presents a distributed information extraction and visualisation service, called the mapping service, for maximising information return from large-scale wireless sensor networks. Such a service would greatly simplify the production of higher-level, information-rich, representations suitable for informing other network services and the delivery of field information visualisations. The mapping service utilises a blend of inductive and deductive models to map sense data accurately using externally available knowledge. It utilises the special characteristics of the application domain to render visualisations in a map format that are a precise reflection of the concrete reality. This service is suitable for visualising an arbitrary number of sense modalities. It is capable of visualising from multiple independent types of the sense data to overcome the limitations of generating visualisations from a single type of sense modality. Furthermore, the mapping service responds dynamically to changes in the environmental conditions, which may affect the visualisation performance by continuously updating the application domain model in a distributed manner. Finally, a distributed self-adaptation function is proposed with the goal of saving more power and generating more accurate data visualisation. We conduct comprehensive experimentation to evaluate the performance of our mapping service and show that it achieves low communication overhead, produces maps of high fidelity, and further minimises the mapping predictive error dynamically through integrating the application domain model in the mapping service.

  6. 48 CFR 1552.216-73 - Fixed rates for services-indefinite delivery/indefinite quantity contract.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-indefinite delivery/indefinite quantity contract. 1552.216-73 Section 1552.216-73 Federal Acquisition... CLAUSES Texts of Provisions and Clauses 1552.216-73 Fixed rates for services—indefinite delivery... rates for services in indefinite delivery/indefinite quantity contracts. When the contract contains...

  7. 78 FR 39200 - Federal Earth Stations-Non-Federal Fixed Satellite Service Space Stations; Spectrum for Non...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-01

    ...-11341; FCC 13-65] Federal Earth Stations--Non-Federal Fixed Satellite Service Space Stations; Spectrum... rule. SUMMARY: This document proposes to make spectrum allocation proposals for three different space... makes alternative proposals to modify the Allocation Table to provide access to spectrum on...

  8. STS-103 crew pose at 195-foot level of Fixed Service Structure

    NASA Technical Reports Server (NTRS)

    1999-01-01

    At the 195-foot level of the Fixed Service Structure on Launch Pad 39B, the STS-103 crew take a break from Terminal Countdown Demonstration Test (TCDT) activities. Standing from left to right are Mission Specialists Jean-Frangois Clervoy of France and Claude Nicollier of Switzerland, who are with the European Space Agency; Commander Curtis L. Brown Jr.; Pilot Scott J. Kelly; and Mission Specialists John M. Grunsfeld (Ph.D.), C. Michael Foale (Ph.D.) and Steven L. Smith. The TCDT provides the crew with the emergency egress training, opportunities to inspect their mission payloads in the orbiter's payload bay, and simulated countdown exercises. STS-103 is a 'call-up' mission due to the need to replace and repair portions of the Hubble Space Telescope, including the gyroscopes that allow the telescope to point at stars, galaxies and planets. The STS-103 crew will be replacing a Fine Guidance Sensor, an older computer with a new enhanced model, an older data tape recorder with a solid-state digital recorder, a failed spare transmitter with a new one, and degraded insulation on the telescope with new thermal insulation. The crew will also install a Battery Voltage/Temperature Improvement Kit to protect the spacecraft batteries from overcharging and overheating when the telescope goes into a safe mode. Four EVA's are planned to make the necessary repairs and replacements on the telescope. The mission is targeted for launch Dec. 6 at 2:37 a.m. EST.

  9. STS-103 crew pose at 195-foot level of Fixed Service Structure

    NASA Technical Reports Server (NTRS)

    1999-01-01

    At the 195-foot level of the Fixed Service Structure on Launch Pad 39B, the STS-103 crew take a break from Terminal Countdown Demonstration Test (TCDT) activities. Standing from left to right are Mission Specialists Jean-Frangois Clervoy of France and Claude Nicollier of Switzerland, who are with the European Space Agency; Commander Curtis L. Brown Jr.; Pilot Scott J. Kelly; and Mission Specialists John M. Grunsfeld (Ph.D.), C. Michael Foale (Ph.D.) and Steven L. Smith. The TCDT provides the crew with the emergency egress training, opportunities to inspect their mission payloads in the orbiter's payload bay, and simulated countdown exercises. STS-103 is a 'call-up' mission due to the need to replace and repair portions of the Hubble Space Telescope, including the gyroscopes that allow the telescope to point at stars, galaxies and planets. The STS-103 crew will be replacing a Fine Guidance Sensor, an older computer with a new enhanced model, an older data tape recorder with a solid-state digital recorder, a failed spare transmitter with a new one, and degraded insulation on the telescope with new thermal insulation. The crew will also install a Battery Voltage/Temperature Improvement Kit to protect the spacecraft batteries from overcharging and overheating when the telescope goes into a safe mode. Four EVA's are planned to make the necessary repairs and replacements on the telescope. The mission is targeted for launch Dec. 6 at 2:37 a.m. EST.

  10. Development of an Indoor Location Based Service Test Bed and Geographic Information System with a Wireless Sensor Network

    PubMed Central

    Jan, Shau-Shiun; Hsu, Li-Ta; Tsai, Wen-Ming

    2010-01-01

    In order to provide the seamless navigation and positioning services for indoor environments, an indoor location based service (LBS) test bed is developed to integrate the indoor positioning system and the indoor three-dimensional (3D) geographic information system (GIS). A wireless sensor network (WSN) is used in the developed indoor positioning system. Considering the power consumption, in this paper the ZigBee radio is used as the wireless protocol, and the received signal strength (RSS) fingerprinting positioning method is applied as the primary indoor positioning algorithm. The matching processes of the user location include the nearest neighbor (NN) algorithm, the K-weighted nearest neighbors (KWNN) algorithm, and the probabilistic approach. To enhance the positioning accuracy for the dynamic user, the particle filter is used to improve the positioning performance. As part of this research, a 3D indoor GIS is developed to be used with the indoor positioning system. This involved using the computer-aided design (CAD) software and the virtual reality markup language (VRML) to implement a prototype indoor LBS test bed. Thus, a rapid and practical procedure for constructing a 3D indoor GIS is proposed, and this GIS is easy to update and maintenance for users. The building of the Department of Aeronautics and Astronautics at National Cheng Kung University in Taiwan is used as an example to assess the performance of various algorithms for the indoor positioning system. PMID:22319282

  11. Development of an indoor location based service test bed and geographic information system with a wireless sensor network.

    PubMed

    Jan, Shau-Shiun; Hsu, Li-Ta; Tsai, Wen-Ming

    2010-01-01

    In order to provide the seamless navigation and positioning services for indoor environments, an indoor location based service (LBS) test bed is developed to integrate the indoor positioning system and the indoor three-dimensional (3D) geographic information system (GIS). A wireless sensor network (WSN) is used in the developed indoor positioning system. Considering the power consumption, in this paper the ZigBee radio is used as the wireless protocol, and the received signal strength (RSS) fingerprinting positioning method is applied as the primary indoor positioning algorithm. The matching processes of the user location include the nearest neighbor (NN) algorithm, the K-weighted nearest neighbors (KWNN) algorithm, and the probabilistic approach. To enhance the positioning accuracy for the dynamic user, the particle filter is used to improve the positioning performance. As part of this research, a 3D indoor GIS is developed to be used with the indoor positioning system. This involved using the computer-aided design (CAD) software and the virtual reality markup language (VRML) to implement a prototype indoor LBS test bed. Thus, a rapid and practical procedure for constructing a 3D indoor GIS is proposed, and this GIS is easy to update and maintenance for users. The building of the Department of Aeronautics and Astronautics at National Cheng Kung University in Taiwan is used as an example to assess the performance of various algorithms for the indoor positioning system.

  12. The 30/20 GHz fixed communications systems service demand assessment. Volume 3: Appendices

    NASA Technical Reports Server (NTRS)

    Gabriszeski, T.; Reiner, P.; Rogers, J.; Terbo, W.

    1979-01-01

    The market analysis of voice, video, and data 18/30 GHz communications systems services and satellite transmission services is discussed. Detail calculations, computer displays of traffic, survey questionnaires, and detailed service forecasts are presented.

  13. Indoor localization for global information service using acoustic wireless sensor network

    NASA Astrophysics Data System (ADS)

    Desai, Pratikkumar; Baine, Nicholas; Rattan, Kuldip S.

    2011-06-01

    Indoor localization with sensing capabilities is the missing link for a Geospatial Information System and sensor web. The sensor network is capable of environmental monitoring and geo-tagging sensor data. This paper presents a unique algorithm which uses fusion of Radio Signal Strength Indicator and Time Difference of Arrival for centimeter level accurate indoor localization using wireless sensor network motes. The paper also proposes the integration of various environmental sensors with wireless sensor network. The acquired sensor data can be geo-tagged with the translated global coordinates and additional sensory metadata. With the use of semantic sensor web, this sensor information can be utilized in various decision making scenarios for critical situations. The main goal of the paper is to use indoor localization assisted by sensor fusion and semantic web for first responders in emergency scenarios.

  14. 76 FR 74722 - Facilitating the Use of Microwave for Wireless Backhaul and Other Uses and Providing Additional...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-01

    ... COMMISSION 47 CFR Part 101 Facilitating the Use of Microwave for Wireless Backhaul and Other Uses and Providing Additional Flexibility To Broadcast Auxiliary Service and Operational Fixed Microwave Licensees... proceeding continuing efforts to increase flexibility in the use of microwave services licensed under our...

  15. The 18 and 30 GHz fixed service communications satellite system study. [to determine the cost and performance characteristics

    NASA Technical Reports Server (NTRS)

    Bronstein, L. M.

    1979-01-01

    The use of the 18 and 30 GHz bands for fixed service satellite communications is examined. The cost and performance expected of 18 and 30 GHz hardware is assessed, selected trunking and direct to user concepts are optimized, and the cost of these systems are estimated. The effect of rain attenuation on the technical and economic viability of the system and methods circumventing the problem are discussed. Technology developments are investigated and cost estimates of these developments are presented.

  16. Sharing of the band 12.2-12.7 GHz between the braodcasting-satellite and fixed services

    NASA Astrophysics Data System (ADS)

    Akima, H.

    1980-01-01

    The United States Administration has proposed for the 1979 WARC (World Administrative Radio Conference) to move the BSS (Broadcasting-Satellite Service) in ITU (International Telecommunication Union) Region 2 from the band 11.7-12.2 GHz to the band 12.2-12.7 GHz, which is also allocated to the terrestrial FS (fixed service). This report discusses the potential of sharing between the BSS and the FS in the band 12.2-12.7 GHz. It is concluded that sharing is feasible under certain conditions.

  17. CoR-MAC: Contention over Reservation MAC Protocol for Time-Critical Services in Wireless Body Area Sensor Networks.

    PubMed

    Yu, Jeongseok; Park, Laihyuk; Park, Junho; Cho, Sungrae; Keum, Changsup

    2016-05-09

    Reserving time slots for urgent data, such as life-critical information, seems to be very attractive to guarantee their deadline requirements in wireless body area sensor networks (WBASNs). On the other hand, this reservation imposes a negative impact on performance for the utilization of a channel. This paper proposes a new channel access scheme referred to as the contention over reservation MAC (CoR-MAC) protocol for time-critical services in wireless body area sensor networks. CoR-MAC uses the dual reservation; if the reserved time slots are known to be vacant, other nodes can access the time slots by contention-based reservation to maximize the utilization of a channel and decrease the delay of the data. To measure the effectiveness of the proposed scheme against IEEE 802.15.4 and IEEE 802.15.6, we evaluated their performances with various performance indexes. The CoR-MAC showed 50% to 850% performance improvement in terms of the delay of urgent and time-critical data according to the number of nodes.

  18. CoR-MAC: Contention over Reservation MAC Protocol for Time-Critical Services in Wireless Body Area Sensor Networks

    PubMed Central

    Yu, Jeongseok; Park, Laihyuk; Park, Junho; Cho, Sungrae; Keum, Changsup

    2016-01-01

    Reserving time slots for urgent data, such as life-critical information, seems to be very attractive to guarantee their deadline requirements in wireless body area sensor networks (WBASNs). On the other hand, this reservation imposes a negative impact on performance for the utilization of a channel. This paper proposes a new channel access scheme referred to as the contention over reservation MAC (CoR-MAC) protocol for time-critical services in wireless body area sensor networks. CoR-MAC uses the dual reservation; if the reserved time slots are known to be vacant, other nodes can access the time slots by contention-based reservation to maximize the utilization of a channel and decrease the delay of the data. To measure the effectiveness of the proposed scheme against IEEE 802.15.4 and IEEE 802.15.6, we evaluated their performances with various performance indexes. The CoR-MAC showed 50% to 850% performance improvement in terms of the delay of urgent and time-critical data according to the number of nodes. PMID:27171085

  19. 47 CFR 27.1250 - Transition of the 2150-2160/62 MHz band from the Broadband Radio Service to the Advanced Wireless...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Advanced Wireless Service (AWS). The rules in this section provide for a transition period during which AWS... 47 Telecommunication 2 2010-10-01 2010-10-01 false Transition of the 2150-2160/62 MHz band from... 2150-2160/62 Mhz Band § 27.1250 Transition of the 2150-2160/62 MHz band from the Broadband Radio...

  20. Evaluation of ground ambulance, rotor-wing, and fixed-wing aircraft services.

    PubMed

    Schneider, C; Gomez, M; Lee, R

    1992-07-01

    It is hoped that this article has offered insightful suggestions and criteria in choosing the most appropriate method to transport patients. Ground ambulances, rotor-wing, and fixed-wing aircraft each have advantages and disadvantages in particular circumstances. The advantages and disadvantages of any mode of transport must be considered to best meet the needs of the patient. In the twentieth century alone, great strides have been made in the field of emergency stabilization and transport. An efficient, well-trained ground ambulance program remains the backbone of prehospital and interhospital transport systems. Helicopters and fixed-wing transports must be integrated into the EMS system. One advantage of the helicopter and fixed-wing aircraft is rapid travel times when time is critical. As Hicks et al said, "early resuscitation and timely transfer of selected patients are critical factors in reducing morbidity and mortality." The future holds many possibilities for enhanced patient transport. Hospitals may be able to use tilt-rotor, vertical landing, fixed-wing aircraft to combine the advantages of helicopter and fixed-wing aircraft. After all, our primary goal is to get the right patient, with the right personnel, to the right place in the right amount of time.

  1. Opportunistic Wireless Charging System Design for an On-Demand Shuttle Service

    SciTech Connect

    Meintz, Andrew; Doubleday, Kate; Markel, Tony

    2016-06-29

    System right-sizing is critical to the implementation of in-motion wireless power transfer (WPT) for electric vehicles. This study evaluates potential system designs for an on-demand employee shuttle by determining the required battery size based on the rated power at a variable number of charging locations. Vehicle power and state of charge are simulated over the drive cycle, based on position and velocity data at every second from the existing shuttle. Adding just one WPT location can halve the battery size. Many configurations are capable of self-sustaining with WPT, while others benefit from supplemental stationary charging.

  2. Wireless local area network security.

    PubMed

    Bergeron, Bryan P

    2004-01-01

    Wireless local area networks (WLANs) are increasingly popular in clinical settings because they facilitate the use of wireless PDAs, laptops, and other pervasive computing devices at the point of care. However, because of the relative immaturity of wireless network technology and evolving standards, WLANs, if improperly configured, can present significant security risks. Understanding the security limitations of the technology and available fixes can help minimize the risks of clinical data loss and maintain compliance with HIPAA guidelines.

  3. The 30/20 GHz fixed communications systems service demand assessment. Volume 2: Main report

    NASA Technical Reports Server (NTRS)

    Gamble, R. B.; Seltzer, H. R.; Speter, K. M.; Westheimer, M.

    1979-01-01

    A forecast of demand for telecommunications services through the year 2000 is presented with particular reference to demand for satellite communications. Estimates of demand are provided for voice, video, and data services and for various subcategories of these services. The results are converted to a common digital measure in terms of terabits per year and aggregated to obtain total demand projections.

  4. The 30/20 GHz fixed communications systems service demand assessment. Volume 3: Annex

    NASA Technical Reports Server (NTRS)

    Gamble, R. B.; Seltzer, H. R.; Speter, K. M.; Westheimer, M.

    1979-01-01

    A review of studies forecasting the communication market in the United States is given. The applicability of these forecasts to assessment of demand for the 30/20 GHz fixed communications system is analyzed. Costs for the 30/20 satellite trunking systems are presented and compared with the cost of terrestrial communications.

  5. A Seamless Handoff Scheme with Access Point Load Balance for Real-Time Services Support in 802.11 Wireless LANs

    NASA Astrophysics Data System (ADS)

    Manodham, Thavisak; Loyola, Luis; Miki, Tetsuya

    IEEE 802.11 wirelesses LANs (WLANs) have been rapidly deployed in enterprises, public areas, and households. Voice-over-IP (VoIP) and similar applications are now commonly used in mobile devices over wireless networks. Recent works have improved the quality of service (QoS) offering higher data rates to support various kinds of real-time applications. However, besides the need for higher data rates, seamless handoff and load balancing among APs are key issues that must be addressed in order to continue supporting real-time services across wireless LANs and providing fair services to all users. In this paper, we introduce a novel access point (AP) with two transceivers that improves network efficiency by supporting seamless handoff and traffic load balancing in a wireless network. In our proposed scheme, the novel AP uses the second transceiver to scan and find neighboring STAs in the transmission range and then sends the results to neighboring APs, which compare and analyze whether or not the STA should perform a handoff. The initial results from our simulations show that the novel AP module is more effective than the conventional scheme and a related work in terms of providing a handoff process with low latency and sharing traffic load with neighbor APs.

  6. Delay guaranteed VoD services over group-based integrated fiber-wireless (FiWi) access networks with energy efficiency

    NASA Astrophysics Data System (ADS)

    Li, Yan; Dai, Shifang; Chang, Xiangmao

    2015-08-01

    In group-based fiber-wireless (FiWi) access networks, where wireless clients are divided into several groups according to their interested Internet services, VoD services will meet new challenges considering the diversity of video requesting probability for each wireless group. In this paper, we categorize wireless groups into "video-hot" group with great interest in VoD services and "video-cold" group with infrequent video requesting. For video requests from "video-hot" groups, we firstly propose an energy-efficient optical network unit (ONU) selection approach to reduce ONU power consumption by selecting a subset of ONUs to support such requests, then our previously proposed rebroadcast and patching scheme can be effectively applied. For video requests from "video-cold" groups, a batched multicasting scheme is presented for energy and bandwidth saving. Both of the VoD schemes mentioned in this study are with the aim to minimize worst-case playback delay (WPD) which is particularly important as Internet users. In view of that some ONUs may need to handle video requests from two kinds of group, optimal ONU channel assignment aims to minimize weighted overall WPD is also studied. The efficiency of the work is finally demonstrated by the simulations.

  7. The 18/30 GHz fixed communications system service demand assessment. Volume 2: Main text

    NASA Technical Reports Server (NTRS)

    Gabriszeski, T.; Reiner, P.; Rogers, J.; Terbo, W.

    1979-01-01

    The total demand for communications services, and satellite transmission services at the 4/6 GHz, 12/14 GHz, and 18/30 GHz frequencies is assessed. The services are voice, video, and data services. Traffic demand, by service, is distributed by geographical regions, population density, and distance between serving points. Further distribution of traffic is made among four major end user groups: business, government, institutions and private individuals. A traffic demand analysis is performed on a typical metropolitan city to examine service distribution trends. The projected cost of C and Ku band satellite systems are compared on an individual service basis to projected terrestrial rates. Separation of traffic between transmission systems, including 18/30 GHz systems, is based on cost, user, and technical considerations.

  8. Video summarization based tele-endoscopy: a service to efficiently manage visual data generated during wireless capsule endoscopy procedure.

    PubMed

    Mehmood, Irfan; Sajjad, Muhammad; Baik, Sung Wook

    2014-09-01

    Wireless capsule endoscopy (WCE) has great advantages over traditional endoscopy because it is portable and easy to use. More importantly, WCE combined with mobile computing ensures rapid transmission of diagnostic data to hospitals and enables off-site senior gastroenterologists to offer timely decision making support. However, during this WCE process, video data are produced in huge amounts, but only a limited amount of data is actually useful for diagnosis. The sharing and analysis of this video data becomes a challenging task due the constraints such as limited memory, energy, and communication capability. In order to facilitate efficient WCE data collection and browsing tasks, we present a video summarization-based tele-endoscopy service that estimates the semantically relevant video frames from the perspective of gastroenterologists. For this purpose, image moments, curvature, and multi-scale contrast are computed and are fused to obtain the saliency map of each frame. This saliency map is used to select keyframes. The proposed tele-endoscopy service selects keyframes based on their relevance to the disease diagnosis. This ensures the sending of diagnostically relevant frames to the gastroenterologist instead of sending all the data, thus saving transmission costs and bandwidth. The proposed framework also saves storage costs as well as the precious time of doctors in browsing patient's information. The qualitative and quantitative results are encouraging and show that the proposed service provides video keyframes to the gastroenterologists without discarding important information.

  9. An Opportunistic Wireless Charging System Design for an On-Demand Shuttle Service: Preprint

    SciTech Connect

    Doubleday, Kate; Meintz, Andrew; Markel, Tony

    2016-08-01

    System right-sizing is critical to implementation of in-motion wireless power transfer (WPT) for electric vehicles. This study introduces a modeling tool, WPTSim, which uses one-second speed, location, and road grade data from an on-demand employee shuttle in operation to simulate the incorporation of WPT at fine granularity. Vehicle power and state of charge are simulated over the drive cycle to evaluate potential system designs. The required battery capacity is determined based on the rated power at a variable number of charging locations. Adding just one WPT location can more than halve the battery capacity needed. Many configurations are capable of being self sustaining with WPT, while others benefit from supplemental stationary charging.

  10. Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs with Extended Service Range

    NASA Astrophysics Data System (ADS)

    Choi, Woo-Yong

    2011-11-01

    In this paper, we propose the efficient reliable multicast MAC protocol by which the AP (Access Point) can transmit reliably its multicast data frames to the recipients in the AP's one-hop or two-hop transmission range. The AP uses the STAs (Stations) that are directly associated with itself as the relays for the data delivery to the remote recipients that cannot be reached directly from itself. Based on the connectivity information among the recipients, the reliable multicast MAC protocol optimizes the number of the RAK (Request for ACK) frame transmissions in a reasonable computational time. Numerical examples show that our proposed MAC protocol significantly enhances the MAC performance compared with the BMMM (Batch Mode Multicast MAC) protocol that is extended to support the recipients that are in the AP's one-hop or two-hop transmission range in IEEE 802.11 wireless LANs.

  11. An Opportunistic Wireless Charging System Design for an On-Demand Shuttle Service

    SciTech Connect

    Doubleday, Kate; Meintz, Andrew; Markel, Tony

    2016-07-25

    System right-sizing is critical to implementation of in-motion wireless power transfer (WPT) for electric vehicles. This study introduces a modeling tool, WPTSim, which uses one-second speed, location, and road grade data from an on-demand employee shuttle in operation to simulate the incorporation of WPT at fine granularity. Vehicle power and state of charge are simulated over the drive cycle to evaluate potential system designs. The required battery capacity is determined based on the rated power at a variable number of charging locations. Adding just one WPT location can more than halve the battery capacity needed. Many configurations are capable of being self sustaining with WPT, while others benefit from supplemental stationary charging.

  12. The 18/30 GHz fixed communications system service demand assessment. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Gabriszeski, T.; Reiner, P.; Rogers, J.; Terbo, W.

    1979-01-01

    The total demand for voice, video, and data communications services, and satellite transmission services at the 4/6 GHz, 12/14 GHz, and 18/30 GHz frequencies is discussed. Major study objectives, overall methodology, results, and general observations about a satellite systems market characteristics and trends are summarized.

  13. 78 FR 14920 - Earth Stations Aboard Aircraft Communicating With Fixed-Satellite Service Geostationary-Orbit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-08

    ... licensing of two-way in-flight broadband services, including Internet access, to passengers and flight crews..., DC 20554. The document is also available for download over the Internet at http://hraunfoss.fcc.gov...

  14. Location service for wireless network using improved RSS-based cellular localisation

    NASA Astrophysics Data System (ADS)

    Fayaz, Sara; Sarrafian, Sara

    2014-06-01

    Value-added services, especially in mobile environments, have recently become the key component of making more profit and attracting more subscribers. One of the most commonly used such service is location-based advertiser services. The main issue which should be considered in providing such services is determining the position of the mobile terminals precisely. In this paper, one pattern recognition localisation method based on the signal strength appropriated for implementing a location-based service is presented. The main aim is to introduce some practical solutions to decrease error and computational load and also eliminate the necessity of updating the database. Practical results illustrate high accuracy of this technique and its suitability to apply in such services. The mean error declines to 9.7 m and mean error corresponding to CDF = 67% and CDF = 95% are less than 11 m and 23 m, respectively. We also present a location-based advertising service, in which the customer's interests and local time are considered, in order to enhance the efficiency and individualism of this service.

  15. Providing a children's palliative care service in the community through fixed-term grants: the staff perspective.

    PubMed

    Beringer, A J; Eaton, N M; Jones, G L

    2007-09-01

    Children's palliative care services have recently been awarded fixed-term grants, aimed at improving the provision of care for children with life-limiting conditions in the community. We report findings of a qualitative study to investigate the experience of a cohort of community children's nurses from teams involved in setting up or extending community-based children's palliative care services. The purpose of the study was to identify factors that affect service delivery, from the staff perspective, and to suggest ways of promoting their sustainable development. Semi-structured telephone interviews were conducted with 21 nurses from 12 different teams providing palliative care for children at home and in hospices. Participants were questioned about the services they provided and their own roles in that provision. NVIVO qualitative data analysis software was used to explore themes arising from the transcribed recorded interviews. Key findings were the importance of physical location in facilitating multidisciplinary communication, the importance of defining role boundaries between existing and new providers of children's palliative care, and the potentially detrimental impact of insecure funding on referral patterns and recruitment to posts. Staff named the opportunity to offer direct 'hands-on' care to families, access to work-based support and networking opportunities as important factors in helping them cope with the stresses involved in managing finite resources and the emotional challenges of their work. The maintenance of a mixed caseload with a significant proportion of direct care, provision of ongoing support and clearly defined roles are recommended as means of bolstering the ability of staff to develop their services. The deliberate locating of services to enhance communication between staff and guidance on the preparation of funding applications may further contribute to the sustainability of these services.

  16. 48 CFR 52.246-4 - Inspection of Services-Fixed-Price.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... contract requires. (c) The Government has the right to inspect and test all services called for by the... shall perform inspections and tests in a manner that will not unduly delay the work. (d) If the Government performs inspections or tests on the premises of the Contractor or a subcontractor, the...

  17. 47 CFR 25.210 - Technical requirements for space stations in the Fixed-Satellite Service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-Satellite Service in the 17.3-17.8 GHz band (space-to-Earth), shall employ state-of-the-art full frequency... longitudinal tolerance, and except as provided in Section 25.283(b) (End-of-life Disposal). (k) Antenna...

  18. The 30/20 GHz fixed communications systems service demand assessment. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Gamble, R. B.; Seltzer, H. R.; Speter, K. M.; Westheimer, M.

    1979-01-01

    Demand for telecommunications services is forecasted for the period 1980-2000, with particular reference to that portion of the demand associated with satellite communications. Overall demand for telecommunications is predicted to increase by a factor of five over the period studied and the satellite portion of demand will increase even more rapidly. Traffic demand is separately estimated for voice, video, and data services and is also described as a function of distance traveled and city size. The satellite component of projected demand is compared with the capacity available in the C and Ku satellite bands and it is projected that new satellite technology and the implementation of Ka band transmission will be needed in the decade of the 1990's.

  19. Distributed denial of service (DDoS) attack in cloud- assisted wireless body area networks: a systematic literature review.

    PubMed

    Latif, Rabia; Abbas, Haider; Assar, Saïd

    2014-11-01

    Wireless Body Area Networks (WBANs) have emerged as a promising technology that has shown enormous potential in improving the quality of healthcare, and has thus found a broad range of medical applications from ubiquitous health monitoring to emergency medical response systems. The huge amount of highly sensitive data collected and generated by WBAN nodes requires an ascendable and secure storage and processing infrastructure. Given the limited resources of WBAN nodes for storage and processing, the integration of WBANs and cloud computing may provide a powerful solution. However, despite the benefits of cloud-assisted WBAN, several security issues and challenges remain. Among these, data availability is the most nagging security issue. The most serious threat to data availability is a distributed denial of service (DDoS) attack that directly affects the all-time availability of a patient's data. The existing solutions for standalone WBANs and sensor networks are not applicable in the cloud. The purpose of this review paper is to identify the most threatening types of DDoS attacks affecting the availability of a cloud-assisted WBAN and review the state-of-the-art detection mechanisms for the identified DDoS attacks.

  20. 76 FR 65970 - Facilitating the use of Microwave for Wireless Backhaul and Other Uses and Providing Additional...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-25

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 101 Facilitating the use of Microwave for Wireless Backhaul and Other Uses and Providing Additional Flexibility To Broadcast Auxiliary Service and Operational Fixed Microwave Licensees...

  1. Faith in the 'cultural fix': limits to a planned cultural change program in a rural health service.

    PubMed

    Mahony, K

    2000-01-01

    This paper, by way of a narrative on the author's participation, explains the limits to a planned cultural change program in a large rural health service. Cultural change was identified by the CEO as crucial to the success of a major restructuring of the service, and the attitudes and beliefs of the 'old guard' were considered to be constraining progress. Advocates of cultural integration contend that shared core values across an organisation can overcome such obstacles. This is a matter of faith. An application of Habermasian theory suggests that organisational leaders are drawing on traditional/religious beliefs and practices to bolster their visions and missions at a time of motivational crisis. Though a need for cultural change in some sectors of the health services is acknowledged, the particular challenges in attempting to manipulate the traditionally embedded culture and sub-cultures of the health services is highlighted. An analysis of some of the ideas and beliefs surrounding authority, deference and discipline is undertaken. It is argued that the ritualistic reinforcement of these beliefs and the reproduction of sub-cultures along material and ideal interests militate against the implementation of objectives delineated by the CEO. While cultural analysis has revealed the irrational face of organisations and can bring to conscious awareness the taken-for-granted beliefs which inform behaviour, the cultural integrationists have a further agenda. They aim to manipulate organisational culture to subtly control employees' beliefs and hence behaviour. Cultural control is a covert form of top down authority that can be just as directive and centralizing as bureaucratic control. The author also maintains that cultural change programs alone cannot fix a problem that arose in the macro-economic sphere: a chronic lack of resources ever since the state responded to the economic crisis by cutting funds to health and welfare services.

  2. Optimizing Heat Treatment of Gas Turbine Blades with a Co C Fixed Point for Improved In-service Thermocouples

    NASA Astrophysics Data System (ADS)

    Pearce, J. V.; Machin, G.; Ford, T.; Wardle, S.

    2008-02-01

    Improvement of energy efficiency of jet aircraft is achieved by operating gas turbine engines at higher temperatures. To facilitate this, gas turbine engine manufacturers are continuously developing new alloys for hot-zone turbine blades that will withstand the increased in-service temperatures. A critical part of the manufacture of these blades is heat treatment to ensure that they attain the necessary metallurgical characteristics. Current heat-treatment temperature-control requirements are at the limit of what is achievable with conventional thermocouple calibrations. A project that will allow thermocouple manufacturer CCPI Europe Ltd. to realize uncertainties of ± 1°C, or better, in the calibration of its noble metal thermocouples is described. This will be realized through implementing a Co C eutectic fixed point in CCPI’s calibration chain. As this melts at 1,324°C, very close to the heat-treatment temperatures required, low uncertainties will be obtained. This should yield an increase in effectiveness of the heat-treatment process performed by Bodycote Heat Treatments Ltd., allowing them to respond effectively to the increasingly stringent demands of engine manufacturers. Outside the current project, there is a strong requirement by industry for lower uncertainties at and above 1,300°C. Successful implementation of the current fixed point in an industrial setting is likely to result in rapid take-up by other companies, probably through the supply of ultra-low uncertainty thermocouples, looking to improve their high-temperature processes.

  3. An allotment planning concept and related computer software for planning the fixed satellite service at the 1988 space WARC

    NASA Technical Reports Server (NTRS)

    Miller, Edward F.; Heyward, Ann O.; Ponchak, Denise S.; Spence, Rodney L.; Whyte, Wayne A., Jr.

    1987-01-01

    The authors describe a two-phase approach to allotment planning suitable for use in planning the fixed satellite service at the 1988 Space World Administrative radio Conference (ORB-88). The two phases are (1) the identification of predetermined geostationary arc segments common to groups of administrations and (2) the use of a synthesis program to identify example scenarios of space station placements. The planning approach is described in detail and is related to the objectives of the conference. Computer software has been developed to implement the concepts, and the logic and rationale for identifying predetermined arc segments is discussed. Example scenarios are evaluated to give guidance in the selection of the technical characteristics of space communications systems to be planned. The allotment planning concept described guarantees equitable access to the geostationary orbit, provides flexibility in implementation, and reduces the need for coordination among administrations.

  4. An allotment planning concept and related computer software for planning the fixed satellite service at the 1988 space WARC

    NASA Technical Reports Server (NTRS)

    Miller, Edward F.; Heyward, Ann O.; Ponchak, Denise S.; Spence, Rodney L.; Whyte, Wayne A., Jr.; Zuzek, John E.

    1987-01-01

    Described is a two-phase approach to allotment planning suitable for use in establishing the fixed satellite service at the 1988 Space World Administrative Radio Conference (ORB-88). The two phases are (1) the identification of predetermined geostationary arc segments common togroups of administrations, and (2) the use of a synthesis program to identify example scenarios of space station placements. The planning approach is described in detail and is related to the objectives of the confernece. Computer software has been developed to implement the concepts, and a complete discussion on the logic and rationale for identifying predetermined arc segments is given. Example scenarios are evaluated to give guidance in the selection of the technical characteristics of space communications systems to be planned. The allotment planning concept described guarantees in practice equitable access to the geostationary orbit, provides flexibility in implementation, and reduces the need for coordination among administrations.

  5. An allotment planning concept and related computer software for planning the fixed satellite service at the 1988 space WARC

    NASA Technical Reports Server (NTRS)

    Miller, Edward F.; Heyward, Ann O.; Ponchak, Denise S.; Spence, Rodney L.; Whyte, Wayne A., Jr.

    1987-01-01

    The authors describe a two-phase approach to allotment planning suitable for use in planning the fixed satellite service at the 1988 Space World Administrative radio Conference (ORB-88). The two phases are (1) the identification of predetermined geostationary arc segments common to groups of administrations and (2) the use of a synthesis program to identify example scenarios of space station placements. The planning approach is described in detail and is related to the objectives of the conference. Computer software has been developed to implement the concepts, and the logic and rationale for identifying predetermined arc segments is discussed. Example scenarios are evaluated to give guidance in the selection of the technical characteristics of space communications systems to be planned. The allotment planning concept described guarantees equitable access to the geostationary orbit, provides flexibility in implementation, and reduces the need for coordination among administrations.

  6. Fast Decision Algorithms in Low-Power Embedded Processors for Quality-of-Service Based Connectivity of Mobile Sensors in Heterogeneous Wireless Sensor Networks

    PubMed Central

    Jaraíz-Simón, María D.; Gómez-Pulido, Juan A.; Vega-Rodríguez, Miguel A.; Sánchez-Pérez, Juan M.

    2012-01-01

    When a mobile wireless sensor is moving along heterogeneous wireless sensor networks, it can be under the coverage of more than one network many times. In these situations, the Vertical Handoff process can happen, where the mobile sensor decides to change its connection from a network to the best network among the available ones according to their quality of service characteristics. A fitness function is used for the handoff decision, being desirable to minimize it. This is an optimization problem which consists of the adjustment of a set of weights for the quality of service. Solving this problem efficiently is relevant to heterogeneous wireless sensor networks in many advanced applications. Numerous works can be found in the literature dealing with the vertical handoff decision, although they all suffer from the same shortfall: a non-comparable efficiency. Therefore, the aim of this work is twofold: first, to develop a fast decision algorithm that explores the entire space of possible combinations of weights, searching that one that minimizes the fitness function; and second, to design and implement a system on chip architecture based on reconfigurable hardware and embedded processors to achieve several goals necessary for competitive mobile terminals: good performance, low power consumption, low economic cost, and small area integration. PMID:22438728

  7. Fast decision algorithms in low-power embedded processors for quality-of-service based connectivity of mobile sensors in heterogeneous wireless sensor networks.

    PubMed

    Jaraíz-Simón, María D; Gómez-Pulido, Juan A; Vega-Rodríguez, Miguel A; Sánchez-Pérez, Juan M

    2012-01-01

    When a mobile wireless sensor is moving along heterogeneous wireless sensor networks, it can be under the coverage of more than one network many times. In these situations, the Vertical Handoff process can happen, where the mobile sensor decides to change its connection from a network to the best network among the available ones according to their quality of service characteristics. A fitness function is used for the handoff decision, being desirable to minimize it. This is an optimization problem which consists of the adjustment of a set of weights for the quality of service. Solving this problem efficiently is relevant to heterogeneous wireless sensor networks in many advanced applications. Numerous works can be found in the literature dealing with the vertical handoff decision, although they all suffer from the same shortfall: a non-comparable efficiency. Therefore, the aim of this work is twofold: first, to develop a fast decision algorithm that explores the entire space of possible combinations of weights, searching that one that minimizes the fitness function; and second, to design and implement a system on chip architecture based on reconfigurable hardware and embedded processors to achieve several goals necessary for competitive mobile terminals: good performance, low power consumption, low economic cost, and small area integration.

  8. Usage of Wireless Sensor Networks in a service based spatial data infrastructure for Landslide Monitoring and Early Warning

    NASA Astrophysics Data System (ADS)

    Arnhardt, C.; Fernandez-Steeger, T. M.; Walter, K.; Kallash, A.; Niemeyer, F.; Azzam, R.; Bill, R.

    2007-12-01

    The joint project Sensor based Landslide Early Warning System (SLEWS) aims at a systematic development of a prototyping alarm- and early warning system for the detection of mass movements by application of an ad hoc wireless sensor network (WSN). Next to the development of suitable sensor setups, sensor fusion and network fusion are applied to enhance data quality and reduce false alarm rates. Of special interest is the data retrieval, processing and visualization in GI-Systems. Therefore a suitable serviced based Spatial Data Infrastructure (SDI) will be developed with respect to existing and upcoming Open Geospatial Consortium (OGC) standards.The application of WSN provides a cheap and easy to set up solution for special monitoring and data gathering in large areas. Measurement data from different low-cost transducers for deformation observation (acceleration, displacement, tilting) is collected by distributed sensor nodes (motes), which interact separately and connect each other in a self-organizing manner. Data are collected and aggregated at the beacon (transmission station) and further operations like data pre-processing and compression can be performed. The WSN concept provides next to energy efficiency, miniaturization, real-time monitoring and remote operation, but also new monitoring strategies like sensor and network fusion. Since not only single sensors can be integrated at single motes either cross-validation or redundant sensor setups are possible to enhance data quality. The planned monitoring and information system will include a mobile infrastructure (information technologies and communication components) as well as methods and models to estimate surface deformation parameters (positioning systems). The measurements result in heterogeneous observation sets that have to be integrated in a common adjustment and filtering approach. Reliable real-time information will be obtained using a range of sensor input and algorithms, from which early warnings

  9. Orbit-spectrum sharing between the fixed-satellite and broadcasting-satellite services at 12 GHz

    NASA Technical Reports Server (NTRS)

    Reinhart, E. E.

    1974-01-01

    This paper identifies and evaluates strategies for sharing the geostationary orbit in the band 11.7 to 12.2 GHz between domestic systems in the fixed-satellite and broadcasting-satellite services. The effectiveness of two distinct types of sharing strategies, referred to as spectrum division and orbit division, is determined for various deployments of selected baseline systems representing the two services and for various combinations of sharing tactics such as frequency interleaving, crossed-polarization operation, and crossed-beam operation. Effectiveness is measured by the 'utilization factor', defined as the number of channels provided by the baseline systems when using an assigned share of the orbit-spectrum resource, relative to what they could provide if given the entire resource. Computer simulation is used to verify the intra- and interservice interference compatibility of the assumed deployments. It is concluded that total utilization factors close to 100 percent can be achieved with both spectrum-division and properly-chosen orbit-division strategies.

  10. 75 FR 77602 - Allocation and Designation of Spectrum for Fixed-Satellite Services in the 37.5-38.5 GHz, 40.5-41...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-13

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 25 Allocation and Designation of Spectrum for Fixed-Satellite Services in the 37.5-38.5 GHz, 40.5-41.5 GHz and 48.2-50.2 GHz Frequency Bands AGENCY: Federal Communications...

  11. 75 FR 71064 - Allocation and Designation of Spectrum for Fixed-Satellite Services in the 37.5-38.5 GHz, 40.5-41...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 25 Allocation and Designation of Spectrum for Fixed-Satellite Services in the 37.5-38.5 GHz, 40.5-41.5 GHz and 48.2-50.2 GHz Frequency Bands AGENCY: Federal Communications...

  12. Case for wireless overlay networks

    NASA Astrophysics Data System (ADS)

    Katz, Randy H.; Brewer, Eric A.

    1996-03-01

    Wireless data services, other than those for electronic mail or paging, have thus far been more promising than successful. We believe that future mobile information systems must be built upon heterogeneous wireless overlay networks, extending traditional wired and internetworked processing `islands' to hosts on the move over coverage areas ranging from in-room, in- building, campus, metropolitan, and wide-areas. Unfortunately, network planners continue to think in terms of homogeneous wireless communications systems and technologies. In this paper, we describe a new wireless data networking architecture that integrates diverse wireless technologies into a seamless internetwork. In addition, we describe the applications support services needed to make it possible for applications to continue to operate as mobile hosts roam across such networks. The architecture described herein is being implemented in a testbed at the University of California, Berkeley under joint government/industry sponsorship.

  13. Method and system for spatial data input, manipulation and distribution via an adaptive wireless transceiver

    NASA Technical Reports Server (NTRS)

    Wang, Ray (Inventor)

    2009-01-01

    A method and system for spatial data manipulation input and distribution via an adaptive wireless transceiver. The method and system include a wireless transceiver for automatically and adaptively controlling wireless transmissions using a Waveform-DNA method. The wireless transceiver can operate simultaneously over both the short and long distances. The wireless transceiver is automatically adaptive and wireless devices can send and receive wireless digital and analog data from various sources rapidly in real-time via available networks and network services.

  14. 75 FR 67321 - Wireless E911 Location Accuracy Requirements; E911 Requirements for IP-Enabled Service Providers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-02

    ... site or base station that received the call, and Phase II--which requires wireless carriers to provide... OET Bulletin sets forth the Commission's expectations regarding location accuracy measurement and... will improve accuracy over time as they are blended into each carrier's subscriber base. How else...

  15. Performance Analysis of IIUM Wireless Campus Network

    NASA Astrophysics Data System (ADS)

    Abd Latif, Suhaimi; Masud, Mosharrof H.; Anwar, Farhat

    2013-12-01

    International Islamic University Malaysia (IIUM) is one of the leading universities in the world in terms of quality of education that has been achieved due to providing numerous facilities including wireless services to every enrolled student. The quality of this wireless service is controlled and monitored by Information Technology Division (ITD), an ISO standardized organization under the university. This paper aims to investigate the constraints of wireless campus network of IIUM. It evaluates the performance of the IIUM wireless campus network in terms of delay, throughput and jitter. QualNet 5.2 simulator tool has employed to measure these performances of IIUM wireless campus network. The observation from the simulation result could be one of the influencing factors in improving wireless services for ITD and further improvement.

  16. Breaking Free with Wireless Networks.

    ERIC Educational Resources Information Center

    Fleischman, John

    2002-01-01

    Discusses wireless local area networks (LANs) which typically consist of laptop computers that connect to fixed access points via infrared or radio signals. Topics include wide area networks; personal area networks; problems, including limitations of available bandwidth, interference, and security concerns; use in education; interoperability;…

  17. Wireless Acoustic Measurement System

    NASA Technical Reports Server (NTRS)

    Anderson, Paul D.; Dorland, Wade D.

    2005-01-01

    A prototype wireless acoustic measurement system (WAMS) is one of two main subsystems of the Acoustic Prediction/Measurement Tool, which comprises software, acoustic instrumentation, and electronic hardware combined to afford integrated capabilities for predicting and measuring noise emitted by rocket and jet engines. The other main subsystem is described in "Predicting Rocket or Jet Noise in Real Time" (SSC-00215-1), which appears elsewhere in this issue of NASA Tech Briefs. The WAMS includes analog acoustic measurement instrumentation and analog and digital electronic circuitry combined with computer wireless local-area networking to enable (1) measurement of sound-pressure levels at multiple locations in the sound field of an engine under test and (2) recording and processing of the measurement data. At each field location, the measurements are taken by a portable unit, denoted a field station. There are ten field stations, each of which can take two channels of measurements. Each field station is equipped with two instrumentation microphones, a micro-ATX computer, a wireless network adapter, an environmental enclosure, a directional radio antenna, and a battery power supply. The environmental enclosure shields the computer from weather and from extreme acoustically induced vibrations. The power supply is based on a marine-service lead-acid storage battery that has enough capacity to support operation for as long as 10 hours. A desktop computer serves as a control server for the WAMS. The server is connected to a wireless router for communication with the field stations via a wireless local-area network that complies with wireless-network standard 802.11b of the Institute of Electrical and Electronics Engineers. The router and the wireless network adapters are controlled by use of Linux-compatible driver software. The server runs custom Linux software for synchronizing the recording of measurement data in the field stations. The software includes a module that

  18. Wireless Acoustic Measurement System

    NASA Technical Reports Server (NTRS)

    Anderson, Paul D.; Dorland, Wade D.; Jolly, Ronald L.

    2007-01-01

    A prototype wireless acoustic measurement system (WAMS) is one of two main subsystems of the Acoustic Prediction/ Measurement Tool, which comprises software, acoustic instrumentation, and electronic hardware combined to afford integrated capabilities for predicting and measuring noise emitted by rocket and jet engines. The other main subsystem is described in the article on page 8. The WAMS includes analog acoustic measurement instrumentation and analog and digital electronic circuitry combined with computer wireless local-area networking to enable (1) measurement of sound-pressure levels at multiple locations in the sound field of an engine under test and (2) recording and processing of the measurement data. At each field location, the measurements are taken by a portable unit, denoted a field station. There are ten field stations, each of which can take two channels of measurements. Each field station is equipped with two instrumentation microphones, a micro- ATX computer, a wireless network adapter, an environmental enclosure, a directional radio antenna, and a battery power supply. The environmental enclosure shields the computer from weather and from extreme acoustically induced vibrations. The power supply is based on a marine-service lead-acid storage battery that has enough capacity to support operation for as long as 10 hours. A desktop computer serves as a control server for the WAMS. The server is connected to a wireless router for communication with the field stations via a wireless local-area network that complies with wireless-network standard 802.11b of the Institute of Electrical and Electronics Engineers. The router and the wireless network adapters are controlled by use of Linux-compatible driver software. The server runs custom Linux software for synchronizing the recording of measurement data in the field stations. The software includes a module that provides an intuitive graphical user interface through which an operator at the control server

  19. Wireless LAN Extension

    DTIC Science & Technology

    2003-03-01

    Networks, WIFI (802.11b), Access Point 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT Unclassified 18. SECURITY CLASSIFICATION OF THIS...to hackers trying to access sensitive information or spoil the operation of the network. It is easier to do a Denial of Service (DOS) attack for...because essentially it is a name that identifies a wireless network. Hackers commonly know each manufacturer’s default settings. As such, it is

  20. Insecurity of Wireless Networks

    SciTech Connect

    Sheldon, Frederick T; Weber, John Mark; Yoo, Seong-Moo; Pan, W. David

    2012-01-01

    Wireless is a powerful core technology enabling our global digital infrastructure. Wi-Fi networks are susceptible to attacks on Wired Equivalency Privacy, Wi-Fi Protected Access (WPA), and WPA2. These attack signatures can be profiled into a system that defends against such attacks on the basis of their inherent characteristics. Wi-Fi is the standard protocol for wireless networks used extensively in US critical infrastructures. Since the Wired Equivalency Privacy (WEP) security protocol was broken, the Wi-Fi Protected Access (WPA) protocol has been considered the secure alternative compatible with hardware developed for WEP. However, in November 2008, researchers developed an attack on WPA, allowing forgery of Address Resolution Protocol (ARP) packets. Subsequent enhancements have enabled ARP poisoning, cryptosystem denial of service, and man-in-the-middle attacks. Open source systems and methods (OSSM) have long been used to secure networks against such attacks. This article reviews OSSMs and the results of experimental attacks on WPA. These experiments re-created current attacks in a laboratory setting, recording both wired and wireless traffic. The article discusses methods of intrusion detection and prevention in the context of cyber physical protection of critical Internet infrastructure. The basis for this research is a specialized (and undoubtedly incomplete) taxonomy of Wi-Fi attacks and their adaptations to existing countermeasures and protocol revisions. Ultimately, this article aims to provide a clearer picture of how and why wireless protection protocols and encryption must achieve a more scientific basis for detecting and preventing such attacks.

  1. Wireless Communications. Wireless Network Integration Technology: MIRAI Architecture for Heterogeneous Network

    NASA Astrophysics Data System (ADS)

    Mizuno, Mitsuhiko; Wu, Gang; Havinga, Paul J. M.

    2001-12-01

    One of the keywords that describe next generation wireless communications is "seamless." As part of the e-Japan Plan promoted by the Japanese Government, the MIRAI (Multimedia Integrated network by Radio Access Innovation) project has, as its goal, the development of new technologies to enable seamless integration of various wireless access systems for practical use by the year 2005. This paper describes a heterogeneous network architecture including a common tool, a common platform, and a common access. In particular, software-defined radio technologies are used to develop a multi-service user terminal to access different wireless networks. The common platform for various wireless networks is based on a wireless supporting IPv6 network. A basic access network, separated from other wireless access networks, is used as a means for wireless system discovery, signaling, and paging. A proof-concept experimental demonstration system will be available in March, 2002.

  2. Wireless Communications

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A technology utilization project led to the commercial adaptation of a Space Shuttle Orbiter wireless infrared voice communications system. The technology was adapted to a LAN system by Wilton Industries, one of the participants. Because the system is cable-free, installation charges are saved, and it can be used where cable is impractical. Resultant products include the IRplex 6000. Transceivers can be located anywhere and can include mobile receivers. The system provides wireless LAN coverage up to 44,000 square feet. applications include stock exchange communications, trade shows, emergency communications, etc.

  3. Cascaded neural networks for sequenced propagation estimation, multiuser detection, and adaptive radio resource control of third-generation wireless networks for multimedia services

    NASA Astrophysics Data System (ADS)

    Hortos, William S.

    1999-03-01

    A hybrid neural network approach is presented to estimate radio propagation characteristics and multiuser interference and to evaluate their combined impact on throughput, latency and information loss in third-generation (3G) wireless networks. The latter three performance parameters influence the quality of service (QoS) for multimedia services under consideration for 3G networks. These networks, based on a hierarchical architecture of overlaying macrocells on top of micro- and picocells, are planned to operate in mobile urban and indoor environments with service demands emanating from circuit-switched, packet-switched and satellite-based traffic sources. Candidate radio interfaces for these networks employ a form of wideband CDMA in 5-MHz and wider-bandwidth channels, with possible asynchronous operation of the mobile subscribers. The proposed neural network (NN) architecture allocates network resources to optimize QoS metrics. Parameters of the radio propagation channel are estimated, followed by control of an adaptive antenna array at the base station to minimize interference, and then joint multiuser detection is performed at the base station receiver. These adaptive processing stages are implemented as a sequence of NN techniques that provide their estimates as inputs to a final- stage Kohonen self-organizing feature map (SOFM). The SOFM optimizes the allocation of available network resources to satisfy QoS requirements for variable-rate voice, data and video services. As the first stage of the sequence, a modified feed-forward multilayer perceptron NN is trained on the pilot signals of the mobile subscribers to estimate the parameters of shadowing, multipath fading and delays on the uplinks. A recurrent NN (RNN) forms the second stage to control base stations' adaptive antenna arrays to minimize intra-cell interference. The third stage is based on a Hopfield NN (HNN), modified to detect multiple users on the uplink radio channels to mitigate multiaccess

  4. Bradyrhizobium viridifuturi sp. nov., encompassing nitrogen-fixing symbionts of legumes used for green manure and environmental services.

    PubMed

    Helene, Luisa Caroline Ferraz; Delamuta, Jakeline Renata Marçon; Ribeiro, Renan Augusto; Ormeño-Orrillo, Ernesto; Rogel, Marco Antonio; Martínez-Romero, Esperanza; Hungria, Mariangela

    2015-12-01

    Symbiotic nitrogen-fixing bacteria, commonly called rhizobia, are agronomically important because they can provide significant amounts of nitrogen to plants and help in recovery of impoverished soils and improvement of degraded environments. In recent years, with advances in molecular techniques, several studies have shown that these bacteria have high levels of genetic diversity, resulting in taxonomic reclassifications and descriptions of new species. However, despite the advances achieved, highly conserved 16S ribosomal genes (16S rRNA) do not elucidate differences between species of several genera, including the genus Bradyrhizobium. Other methodologies, such as multilocus sequence analysis (MLSA), have been used in such cases, with good results. In this study, three strains (SEMIAs 690T, 6387 and 6428) of the genus Bradyrhizobium, isolated from nitrogen-fixing nodules of Centrosema and Acacia species, without clear taxonomic positions, were studied. These strains differed from genetically closely related species according to the results of MLSA of four housekeeping genes (dnaK, glnII, gyrB and recA) and nucleotide identities of the concatenated genes with those of related species ranged from 87.8 % to 95.7 %, being highest with Bradyrhizobium elkanii. DNA-DNA hybridization (less than 32 % DNA relatedness) and average nucleotide identity values of the whole genomes (less than 90.5 %) indicated that these strains represented a novel species, and phenotypic traits were determined. Our data supported the description of the SEMIA strains as Bradyrhizobium viridifuturi sp. nov., and SEMIA 690T ( = CNPSo 991T = C 100aT = BR 1804T = LMG 28866T), isolated from Centrosema pubescens, was chosen as type strain.

  5. Taming the Wireless Frontier: PDAs, Tablets, and Laptops at Home on the Range.

    ERIC Educational Resources Information Center

    Williams, Joe

    2003-01-01

    Explains how Texas A&M University libraries developed a wireless network, including problems encountered, and describes three wireless services currently being delivered using Personal Digital Assistants (PDAs), tablet PCs, and wireless laptop computers. Topics include costs versus value; data security and access; wireless access points;…

  6. 47 CFR 25.146 - Licensing and operating rules for the non-geostationary satellite orbit Fixed-Satellite Service...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... information shall demonstrate that the proposed NGSO FSS system would not exceed the validation equivalent... Service (NGSO FSS) system in the 10.7-14.5 GHz bands. The technical information shall demonstrate that the... request at any time additional information from the NGSO FSS system applicant or licensee concerning the...

  7. Proposal of Wireless Traffic Control Schemes for Wireless LANs

    NASA Astrophysics Data System (ADS)

    Hiraguri, Takefumi; Ichikawa, Takeo; Iizuka, Masataka; Kubota, Shuji

    This paper proposes two traffic control schemes to support the communication quality of multimedia streaming services such as VoIP and audio/video over IEEE 802.11 wireless LAN systems. The main features of the proposed scheme are bandwidth control for each flow of the multimedia streaming service and load balancing between access points (APs) of the wireless LAN by using information of data link, network and transport layers. The proposed schemes are implemented on a Linux machine which is called the wireless traffic controller (WTC). The WTC connects a high capacity backbone network and an access network to which the APs are attached. We evaluated the performance of the proposed WTC and confirmed that the communication quality of the multimedia streaming would be greatly improved by using this technique.

  8. Wireless Technician

    ERIC Educational Resources Information Center

    Tech Directions, 2011

    2011-01-01

    One of the hottest areas in technology is invisible. Wireless communications allow people to transmit voice messages, data, and other signals through the air without physically connecting senders to receivers with cables or wires. And the technology is spreading at lightning speed. Cellular phones, personal digital assistants, and wireless…

  9. Wireless Technician

    ERIC Educational Resources Information Center

    Tech Directions, 2011

    2011-01-01

    One of the hottest areas in technology is invisible. Wireless communications allow people to transmit voice messages, data, and other signals through the air without physically connecting senders to receivers with cables or wires. And the technology is spreading at lightning speed. Cellular phones, personal digital assistants, and wireless…

  10. Wireless Tots

    ERIC Educational Resources Information Center

    Scott, Lee-Allison

    2003-01-01

    The first wireless technology program for preschoolers was implemented in January at the Primrose School at Bentwater in Atlanta, Georgia, a new corporate school operated by Primrose School Franchising Co. The new school serves as a testing and training facility for groundbreaking educational approaches, including emerging innovations in…

  11. Wireless Protection.

    ERIC Educational Resources Information Center

    Conforti, Fred

    2003-01-01

    Discusses wireless access-control equipment in the school and university setting, particularly the integrated reader lock at the door with a panel interface module at the control panel. Describes its benefits, how it works, and its reliability and security. (EV)

  12. An Approach to Wireless Communications at Sandia National Laboratories

    SciTech Connect

    WITZKE, EDWARD L.

    2002-10-01

    Wireless communication plays an increasing role in military, industrial, public safety, and academic computer networks. Although in general, radio transmitters are not currently permitted in secured areas at Sandia, wireless communications would open new opportunities, allowing mobile and pervasive user access. Without wireless communications, we must live in a ''non-mainstream'' world of fixed, wired networks, where it becomes ever more difficult to attract and retain the best professionals. This report provides a review of the current state of wireless communications, which direction wireless technology is heading, and where wireless technology could be employed at Sandia. A list of recommendations on harnessing the power of wireless communications is provided to aid in building a state-of-the-art communication environment for the 21st century at Sandia.

  13. 76 FR 27745 - Wireless Innovation for Transportation; Request for Information

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-12

    ... example, 4th generation cellular or ``4G.'' However, fixed or mobile local-area coverage such as Wi-Fi, as... mobile wireless broadband technologies and applications for surface transportation, including both wide... that may be either more suitable or more cost- effective to deploy broadband mobile wireless in these...

  14. Wireless Emergency Alerts

    MedlinePlus

    ... Us Main Content Frequently Asked Questions: Wireless Emergency Alerts This section contains answers to a list of frequently asked questions about Wireless Emergency Alerts (WEAs). Why are Wireless Emergency Alerts (WEA) important ...

  15. Quality care, public perception and quick-fix service management: a Delphi study on stressors of hospital doctors in Ireland.

    PubMed

    Hayes, Blanaid; Fitzgerald, Deirdre; Doherty, Sally; Walsh, Gillian

    2015-12-23

    To identify and rank the most significant workplace stressors to which consultants and trainees are exposed within the publicly funded health sector in Ireland. Following a preliminary semistructured telephone interview, a Delphi technique with 3 rounds of reiterative questionnaires was used to obtain consensus. Conducted in Spring 2014, doctors were purposively selected by their college faculty or specialty training body. Consultants and higher specialist trainees who were engaged at a collegiate level with their faculty or professional training body. All were employed in the Irish publicly funded health sector by the Health Services Executive. 49 doctors: 30 consultants (13 male, 17 female) and 19 trainees (7 male, 12 female). Consultants and trainees were from a wide range of hospital specialties including anaesthetics, radiology and psychiatry. Consultants are most concerned with the quality of healthcare management and its impact on service. They are also concerned about the quality of care they provide. They feel undervalued within the negative sociocultural environment that they work. Trainees also feel undervalued with an uncertain future and they also perceive their sociocultural environment as negative. They echo concerns regarding the quality of care they provide. They struggle with the interface between career demands and personal life. This Delphi study sought to explore the working life of doctors in Irish hospitals at a time when resources are scarce. It identified both common and distinct concerns regarding sources of stress for 2 groups of doctors. Its identification of key stressors should guide managers and clinicians towards solutions for improving the quality of patient care and the health of care providers. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  16. 47 CFR 1.1152 - Schedule of annual regulatory fees and filing locations for wireless radio services.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... COMMISSION GENERAL PRACTICE AND PROCEDURE Schedule of Statutory Charges and Procedures for Payment § 1.1152... (per license) Fee amount 1 Address 1. Land Mobile (Above 470 MHz and 220 MHz Local, Base Station & SMRS.... Louis, MO 63197-9000. 4. Shared Use Services Land Mobile (Frequencies Below 470 MHz—except 220 MHz)...

  17. Does long-term intraoral service affect the mechanical properties and elemental composition of multistranded wires of lingual fixed retainers?

    PubMed

    Zinelis, Spiros; Pandis, Nikolaos; Al Jabbari, Youssef S; Eliades, George; Eliades, Theodore

    2017-06-15

    The aim of this study was to evaluate the elemental and mechanical alterations of stainless steel (SS) multistranded orthodontic wires used in fixed retention after intraoral ageing. Two types of 0.022-inch, seven-stranded wires, Lingual Retainer Wire (LRW) and Tru-Chrome (TCH), from the same manufacturer (Rocky Mountain Orthodontics, Denver, Colo, USA) were tested. Thirty-three samples from LRW group and thirty-seven from TCH were collected, whereas three unused wires from each package were used as controls. The median ageing time for LRW was 7.4 years and 8.4 for TCH. All samples were subjected to scanning electron microscope/X-ray energy dispersive spectroscopy analysis. Three spectra were taken from the surface of each wire and then all samples were used for the assessment of Martens hardness, indentation modulus (EIT), and elastic index (ηIT) with the instrumented indentation testing method (IIT). The intraoral ageing time was statistically compared between the two groups by Mann-Whitney rank sum test and the compositional and mechanical properties were compared by unpaired t-test. The Spearman correlation between elemental content and ageing time was carried out for all elements (a = 0.05). No significant differences were found for both the elemental content and for the mechanical properties between the wires tested. Spearman analysis revealed no correlation between elemental content and intraoral time while two groups share statistically equal intraoral ageing times (P > 0.05). Both wires seemed to maintain their mechanical and elemental integrity within a period of 14-year intraoral exposure, whereas no measurable ionic release could be identified.

  18. Quality care, public perception and quick-fix service management: a Delphi study on stressors of hospital doctors in Ireland

    PubMed Central

    Hayes, Blanaid; Fitzgerald, Deirdre; Doherty, Sally; Walsh, Gillian

    2015-01-01

    Objectives To identify and rank the most significant workplace stressors to which consultants and trainees are exposed within the publicly funded health sector in Ireland. Design Following a preliminary semistructured telephone interview, a Delphi technique with 3 rounds of reiterative questionnaires was used to obtain consensus. Conducted in Spring 2014, doctors were purposively selected by their college faculty or specialty training body. Setting Consultants and higher specialist trainees who were engaged at a collegiate level with their faculty or professional training body. All were employed in the Irish publicly funded health sector by the Health Services Executive. Participants 49 doctors: 30 consultants (13 male, 17 female) and 19 trainees (7 male, 12 female). Consultants and trainees were from a wide range of hospital specialties including anaesthetics, radiology and psychiatry. Results Consultants are most concerned with the quality of healthcare management and its impact on service. They are also concerned about the quality of care they provide. They feel undervalued within the negative sociocultural environment that they work. Trainees also feel undervalued with an uncertain future and they also perceive their sociocultural environment as negative. They echo concerns regarding the quality of care they provide. They struggle with the interface between career demands and personal life. Conclusions This Delphi study sought to explore the working life of doctors in Irish hospitals at a time when resources are scarce. It identified both common and distinct concerns regarding sources of stress for 2 groups of doctors. Its identification of key stressors should guide managers and clinicians towards solutions for improving the quality of patient care and the health of care providers. PMID:26700286

  19. Wireless Cybersecurity

    DTIC Science & Technology

    2013-04-01

    circularly symmetric. We have investigated extensions to arbitrary Quadrature Amplitude Modulation ( QAM ) scheme. Notice that QPSK is a very special case...of QAM in that all constellation points are evenly distributed on a scaled unit circle whereas general QAM modulations do not have the constant modulo...operations in which secured wireless networks play an indispensable role. This project led to one PhD dissertation, one pending patent application , two

  20. 77 FR 22720 - Service Rules for Advanced Wireless Services in the 2000-2020 MHz and 2180-2200 MHz Bands, etc.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ..., and licensing rules for flexible terrestrial use of spectrum currently assigned to the Mobile... of spectrum for mobile broadband, provide for flexible use of this spectrum, encourage innovation and... Commission enable the provision of stand-alone terrestrial services in this spectrum. With this proceeding...

  1. Transmission of OFDM wired-wireless quintuple-play services along WDM LR-PONs using centralized broadband impairment compensation.

    PubMed

    Alves, Tiago M F; Morant, Maria; Cartaxo, Adolfo V T; Llorente, Roberto

    2012-06-18

    The simultaneous transmission of four orthogonal frequency-division multiplexing (OFDM)-based signals used to provide quintuple-play services along wavelength division multiplexing (WDM) long-reach passive optical networks (LR-PONs) is demonstrated experimentally. Particularly, the transmission performance of custom signal bearing Gigabit Ethernet data, Worldwide Interoperability for Microwave Access, Long Term Evolution and Ultra Wideband (sub-bands 2 and 3) signals is evaluated for different LR-PONs reaches, considering single-wavelength and WDM transmission, and using a centralized impairment compensation technique at the central office that is transparent to the services provided.It is shown that error vector magnitude-compliant levels are obtained for all the OFDM-based signals in WDM LR-PONs reaching 100 km and that negligible inter-channel crosstalk is obtained for a channel spacing of 100 GHz regardless the OFDM-based signal considered. The successful multi-format OFDM transmission along the 100 km-long WDM LR-PON is achieved in the absence of optical dispersion compensation or single sideband modulation, and it is enabled by the performance improvement provided by the centralized impairment compensation realized.

  2. Wireless Headset Communication System

    NASA Technical Reports Server (NTRS)

    Lau, Wilfred K.; Swanson, Richard; Christensen, Kurt K.

    1995-01-01

    System combines features of pagers, walkie-talkies, and cordless telephones. Wireless headset communication system uses digital modulation on spread spectrum to avoid interference among units. Consists of base station, 4 radio/antenna modules, and as many as 16 remote units with headsets. Base station serves as network controller, audio-mixing network, and interface to such outside services as computers, telephone networks, and other base stations. Developed for use at Kennedy Space Center, system also useful in industrial maintenance, emergency operations, construction, and airport operations. Also, digital capabilities exploited; by adding bar-code readers for use in taking inventories.

  3. Wireless Headset Communication System

    NASA Technical Reports Server (NTRS)

    Lau, Wilfred K.; Swanson, Richard; Christensen, Kurt K.

    1995-01-01

    System combines features of pagers, walkie-talkies, and cordless telephones. Wireless headset communication system uses digital modulation on spread spectrum to avoid interference among units. Consists of base station, 4 radio/antenna modules, and as many as 16 remote units with headsets. Base station serves as network controller, audio-mixing network, and interface to such outside services as computers, telephone networks, and other base stations. Developed for use at Kennedy Space Center, system also useful in industrial maintenance, emergency operations, construction, and airport operations. Also, digital capabilities exploited; by adding bar-code readers for use in taking inventories.

  4. Household wireless electroencephalogram hat

    NASA Astrophysics Data System (ADS)

    Szu, Harold; Hsu, Charles; Moon, Gyu; Yamakawa, Takeshi; Tran, Binh

    2012-06-01

    We applied Compressive Sensing to design an affordable, convenient Brain Machine Interface (BMI) measuring the high spatial density, and real-time process of Electroencephalogram (EEG) brainwaves by a Smartphone. It is useful for therapeutic and mental health monitoring, learning disability biofeedback, handicap interfaces, and war gaming. Its spec is adequate for a biomedical laboratory, without the cables hanging over the head and tethered to a fixed computer terminal. Our improved the intrinsic signal to noise ratio (SNR) by using the non-uniform placement of the measuring electrodes to create the proximity of measurement to the source effect. We computing a spatiotemporal average the larger magnitude of EEG data centers in 0.3 second taking on tethered laboratory data, using fuzzy logic, and computing the inside brainwave sources, by Independent Component Analysis (ICA). Consequently, we can overlay them together by non-uniform electrode distribution enhancing the signal noise ratio and therefore the degree of sparseness by threshold. We overcame the conflicting requirements between a high spatial electrode density and precise temporal resolution (beyond Event Related Potential (ERP) P300 brainwave at 0.3 sec), and Smartphone wireless bottleneck of spatiotemporal throughput rate. Our main contribution in this paper is the quality and the speed of iterative compressed image recovery algorithm based on a Block Sparse Code (Baranuick et al, IEEE/IT 2008). As a result, we achieved real-time wireless dynamic measurement of EEG brainwaves, matching well with traditionally tethered high density EEG.

  5. Wireless power transfer system

    DOEpatents

    Wu, Hunter; Sealy, Kylee; Gilchrist, Aaron

    2016-02-23

    A system includes a first stage of an inductive power transfer system with an LCL load resonant converter with a switching section, an LCL tuning circuit, and a primary receiver pad. The IPT system includes a second stage with a secondary receiver pad, a secondary resonant circuit, a secondary rectification circuit, and a secondary decoupling converter. The secondary receiver pad connects to the secondary resonant circuit. The secondary resonant circuit connects to the secondary rectification circuit. The secondary rectification circuit connects to the secondary decoupling converter. The second stage connects to a load. The load includes an energy storage element. The second stage and load are located on a vehicle and the first stage is located at a fixed location. The primary receiver pad wirelessly transfers power to the secondary receiver pad across a gap when the vehicle positions the secondary receiver pad with respect to the primary receiver pad.

  6. Evaluation of wireless data communications at KSC

    NASA Technical Reports Server (NTRS)

    Gejji, Raghvendra R.

    1995-01-01

    This project is motivated by the need for temporary or emergency provisioning of LAN service at KSC. The main goal of the project was to evaluate existing wireless bridge equipment in the KSC environment. Wireless bridge equipment can be used to make a wireless connection between two remotely located LAN segments. This report describes the experimental setup used to evaluate the equipment, including antenna connections, workstation connections, bridge software and workstation software The rangefinder program on the bridge was used to gather data about how the RF propagation environment at KSC affects the performance of the wireless bridge. Data was gathered for indoor as well as outdoor propagation. The report concludes with recommendations on how to take into account the particular terrain and building structures at KSC to design future applications of wireless bridges.

  7. [Development of Bluetooth wireless sensors].

    PubMed

    Moor, C; Schwaibold, M; Roth, H; Schöchlin, J; Bolz, A

    2002-01-01

    Wireless communication could help to overcome current obstacles in medical devices and could enable medical services to offer completely new scenarios in health care. The Bluetooth technology which is the upcoming global market leader in wireless communication turned out to be perfectly suited not only for consumer market products but also in the medical environment [1]. It offers a low power, low cost connection in the medium range of 1-100 m with a bandwidth of currently 723.2 kbaud. This paper describes the development of a wireless ECG device and a Pulse Oximeter. Equipped with a Bluetooth port, the measurement devices are enabled to transmit data between the sensor and a Bluetooth-monitor. Therefore, CSR's Bluetooth protocol embedded two-processor and embedded single-processor architecture has been used.

  8. A Model for QoS - Aware Wireless Communication in Hospitals.

    PubMed

    Alavikia, Zahra; Khadivi, Pejman; Hashemi, Masoud Reza

    2012-01-01

    In the recent decade, research regarding wireless applications in electronic health (e-Health) services has been increasing. The main benefits of using wireless technologies in e-Health applications are simple communications, fast delivery of medical information, reducing treatment cost and also reducing the medical workers' error rate. However, using wireless communications in sensitive healthcare environment raises electromagnetic interference (EMI). One of the most effective methods to avoid the EMI problem is power management. To this end, some of methods have been proposed in the literature to reduce EMI effects in health care environments. However, using these methods may result in nonaccurate interference avoidance and also may increase network complexity. To overcome these problems, we introduce two approaches based on per-user location and hospital sectoring for power management in sensitive healthcare environments. Although reducing transmission power could avoid EMI, it causes a number of successful message deliveries to the access point to decrease and, hence, the quality of service requirements cannot be meet. In this paper, we propose the use of relays for decreasing the probability of outage in the aforementioned scenario. Relay placement is the main factor to enjoy the usefulness of relay station benefits in the network and, therefore, we use the genetic algorithm to compute the optimum positions of a fixed number of relays. We have considered delay and maximum blind point coverage as two main criteria in relay station problem. The performance of the proposed method in outage reduction is investigated through simulations.

  9. Wearable wireless multi-parameter sensor module for physiological monitoring.

    PubMed

    Liverud, Anders E; Vedum, Jon; Fleurey, Franck; Seeberg, Trine M

    2012-01-01

    Advances in low power technology have given new possibilities for continuous physiological monitoring in several domains such as health care with disease prevention and quality of care services and workers in harsh environment. A miniaturized, multifunctional sensor module that transmits sensor data wirelessly using Bluetooth Smart technology has been developed. The wireless communication link is influenced by factors like antenna orientation, reflections, interference and noise. Test results for signal strength measurements for the wireless transmission in various setups are given and discussed.

  10. A Wireless Sensor Enabled by Wireless Power

    PubMed Central

    Lee, Da-Sheng; Liu, Yu-Hong; Lin, Chii-Ruey

    2012-01-01

    Through harvesting energy by wireless charging and delivering data by wireless communication, this study proposes the concept of a wireless sensor enabled by wireless power (WPWS) and reports the fabrication of a prototype for functional tests. One WPWS node consists of wireless power module and sensor module with different chip-type sensors. Its main feature is the dual antenna structure. Following RFID system architecture, a power harvesting antenna was designed to gather power from a standard reader working in the 915 MHz band. Referring to the Modbus protocol, the other wireless communication antenna was integrated on a node to send sensor data in parallel. The dual antenna structure integrates both the advantages of an RFID system and a wireless sensor. Using a standard UHF RFID reader, WPWS can be enabled in a distributed area with a diameter up to 4 m. Working status is similar to that of a passive tag, except that a tag can only be queried statically, while the WPWS can send dynamic data from the sensors. The function is the same as a wireless sensor node. Different WPWSs equipped with temperature and humidity, optical and airflow velocity sensors are tested in this study. All sensors can send back detection data within 8 s. The accuracy is within 8% deviation compared with laboratory equipment. A wireless sensor network enabled by wireless power should be a totally wireless sensor network using WPWS. However, distributed WPWSs only can form a star topology, the simplest topology for constructing a sensor network. Because of shielding effects, it is difficult to apply other complex topologies. Despite this limitation, WPWS still can be used to extend sensor network applications in hazardous environments. Further research is needed to improve WPWS to realize a totally wireless sensor network. PMID:23443370

  11. A wireless sensor enabled by wireless power.

    PubMed

    Lee, Da-Sheng; Liu, Yu-Hong; Lin, Chii-Ruey

    2012-11-22

    Through harvesting energy by wireless charging and delivering data by wireless communication, this study proposes the concept of a wireless sensor enabled by wireless power (WPWS) and reports the fabrication of a prototype for functional tests. One WPWS node consists of wireless power module and sensor module with different chip-type sensors. Its main feature is the dual antenna structure. Following RFID system architecture, a power harvesting antenna was designed to gather power from a standard reader working in the 915 MHz band. Referring to the Modbus protocol, the other wireless communication antenna was integrated on a node to send sensor data in parallel. The dual antenna structure integrates both the advantages of an RFID system and a wireless sensor. Using a standard UHF RFID reader, WPWS can be enabled in a distributed area with a diameter up to 4 m. Working status is similar to that of a passive tag, except that a tag can only be queried statically, while the WPWS can send dynamic data from the sensors. The function is the same as a wireless sensor node. Different WPWSs equipped with temperature and humidity, optical and airflow velocity sensors are tested in this study. All sensors can send back detection data within 8 s. The accuracy is within 8% deviation compared with laboratory equipment. A wireless sensor network enabled by wireless power should be a totally wireless sensor network using WPWS. However, distributed WPWSs only can form a star topology, the simplest topology for constructing a sensor network. Because of shielding effects, it is difficult to apply other complex topologies. Despite this limitation, WPWS still can be used to extend sensor network applications in hazardous environments. Further research is needed to improve WPWS to realize a totally wireless sensor network.

  12. The Wireless War Dance.

    ERIC Educational Resources Information Center

    Moriarty, Laura Joyce

    2001-01-01

    Discusses the use of wireless technology on college campuses. Explores why colleges may want to use the technology, when they should begin to take it seriously, the culture pushing the change, and how schools should approach wireless technology. (EV)

  13. Community Wireless Networks

    ERIC Educational Resources Information Center

    Feld, Harold

    2005-01-01

    With increasing frequency, communities are seeing the arrival of a new class of noncommercial broadband providers: community wireless networks (CWNs). Utilizing the same wireless technologies that many colleges and universities have used to create wireless networks on campus, CWNs are creating broadband access for free or at costs well below…

  14. Community Wireless Networks

    ERIC Educational Resources Information Center

    Feld, Harold

    2005-01-01

    With increasing frequency, communities are seeing the arrival of a new class of noncommercial broadband providers: community wireless networks (CWNs). Utilizing the same wireless technologies that many colleges and universities have used to create wireless networks on campus, CWNs are creating broadband access for free or at costs well below…

  15. Flexible network wireless transceiver and flexible network telemetry transceiver

    DOEpatents

    Brown, Kenneth D.

    2008-08-05

    A transceiver for facilitating two-way wireless communication between a baseband application and other nodes in a wireless network, wherein the transceiver provides baseband communication networking and necessary configuration and control functions along with transmitter, receiver, and antenna functions to enable the wireless communication. More specifically, the transceiver provides a long-range wireless duplex communication node or channel between the baseband application, which is associated with a mobile or fixed space, air, water, or ground vehicle or other platform, and other nodes in the wireless network or grid. The transceiver broadly comprises a communication processor; a flexible telemetry transceiver including a receiver and a transmitter; a power conversion and regulation mechanism; a diplexer; and a phased array antenna system, wherein these various components and certain subcomponents thereof may be separately enclosed and distributable relative to the other components and subcomponents.

  16. The Systems Librarian: Implementing Wireless Networks without Compromising Security

    ERIC Educational Resources Information Center

    Breeding, Marshall

    2005-01-01

    Many libraries are or soon will be offering Wi-Fi, also known as wireless networks. The largest perceived barriers to providing this service are concerns about security. The prime rule when deploying Wi-Fi is segregation, having a clear separation between a public wireless network and the rest of the library?s network. A number of devices can be…

  17. The Systems Librarian: Implementing Wireless Networks without Compromising Security

    ERIC Educational Resources Information Center

    Breeding, Marshall

    2005-01-01

    Many libraries are or soon will be offering Wi-Fi, also known as wireless networks. The largest perceived barriers to providing this service are concerns about security. The prime rule when deploying Wi-Fi is segregation, having a clear separation between a public wireless network and the rest of the library?s network. A number of devices can be…

  18. Full-Duplex DOCSIS/WirelessDOCSIS Fiber Radio Network Employing Packaged AFPMs as Optical/Electrical Transducers

    NASA Astrophysics Data System (ADS)

    Liu, Chin-Pang; Polo, Valentín; van Dijk, Frédéric; Pfrommer, Holger; Ángel Piqueras, Miguel; Herrera, Javier; Martínez, Alejandro; Karlsson, Stefan; Kjebon, Olle; Schatz, Richard; Enard, Alain; Yu, Yichuan; Tsegaye, Tedros; Chuang, Chin-Hsiu; Seeds, Alwyn J.; Martí, Javier

    2007-03-01

    A hybrid fiber radio access network architecture for simultaneous wireline and wireless transmissions of Data-Over-Cable Service Interface Specification (DOCSIS) signals is presented. An all-optical harmonic up-conversion technique using a dual-drive Mach Zehnder modulator provides the downstream optical signal modulated not only at the intermediate frequency in the 600- to 900-MHz band for wireline transmission but also at the up-converted frequency in the 5.45- to 5.75-GHz band for wireless transmission. An InGaAsP/InGaAsP multiple-quantum-well asymmetric Fabry Pérot modulator/detector has been designed, fabricated, and packaged and has been employed in the base station (BS) as an optical/electrical transducer, simultaneously providing the functions of optical intensity modulation and photodetection. At the BS, the DOCSIS signals are recovered at the wireline and wireless frequencies for the respective feeding of a cable access network or a fixed wireless access network in a highly flexible approach. Full-duplex operation has been demonstrated for both access types in an indoor laboratory environment. In a subsequent small-scale field trial, real-life Internet traffic provided by a local community antenna television system operator has been transported over the present hybrid fiber radio access network architecture, and simultaneous transmission of both DOCSIS and digital television signals has also been performed.

  19. Wireless adiabatic power transfer

    SciTech Connect

    Rangelov, A.A.; Suchowski, H.; Silberberg, Y.; Vitanov, N.V.

    2011-03-15

    Research Highlights: > Efficient and robust mid-range wireless energy transfer between two coils. > The adiabatic energy transfer is analogous to adiabatic passage in quantum optics. > Wireless energy transfer is insensitive to any resonant constraints. > Wireless energy transfer is insensitive to noise in the neighborhood of the coils. - Abstract: We propose a technique for efficient mid-range wireless power transfer between two coils, by adapting the process of adiabatic passage for a coherently driven two-state quantum system to the realm of wireless energy transfer. The proposed technique is shown to be robust to noise, resonant constraints, and other interferences that exist in the neighborhood of the coils.

  20. 47 CFR 22.1031 - Temporary fixed stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MOBILE SERVICES Offshore Radiotelephone Service § 22.1031 Temporary fixed stations. The FCC may, upon proper application therefor, authorize the construction and operation of temporary fixed stations in...

  1. 47 CFR 22.1031 - Temporary fixed stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MOBILE SERVICES Offshore Radiotelephone Service § 22.1031 Temporary fixed stations. The FCC may, upon proper application therefor, authorize the construction and operation of temporary fixed stations in...

  2. Fixed prosthodontics: avoiding pulp death.

    PubMed

    1995-11-01

    Fixed prostheses & crowns have become a major part of dental services due to aging population & increase in retention of natural teeth. In some practices, alarming numbers of endodontic procedures are necessary because of pulp damage after prosthesis cementation. Third party payment companies show many teeth receiving crowns require endodontic therapy within 5 years. Following report describes: (1) 14 potential causes of endodontic need related to fixed prosthodontics; & (2) state-of-art concepts to prevent pulp damage.

  3. 47 CFR 101.815 - Stations at temporary fixed locations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Stations at temporary fixed locations. 101.815... SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.815 Stations at temporary fixed locations. (a) Authorizations may be issued upon proper application for the use of frequencies...

  4. 47 CFR 101.815 - Stations at temporary fixed locations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Stations at temporary fixed locations. 101.815... SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.815 Stations at temporary fixed locations. (a) Authorizations may be issued upon proper application for the use of frequencies...

  5. Mobile-host-centric transport protocol for wireless networks

    NASA Astrophysics Data System (ADS)

    Zhang, Liang; Shu, Yantai; Yang, Zhenyu

    2005-10-01

    Reliable transport protocols such as TCP are tuned to perform well in traditional networks where packet losses occur mostly because of congestion. However, networks with wireless and other lossy links also suffer from significant non-congestion-related losses due to reasons such as bit errors and handoffs. TCP responds to all losses by invoking congestion control and avoidance algorithms, resulting in degraded end-to-end performance in wireless and lossy networks. In case of wired-wireless interaction (WLANs), the wireless link is assumed to be the last hop where most of the loss and delay occurs. Since the mobile host is adjacent to the wireless hops, it is obviously better equipped to obtain first-hand knowledge of the wireless links. In the paper, we proposed a mobile-host-centric transport protocol called MCP (Mobile-host Control Protocol) that is like TCP in its general behavior, but allows for better congestion control and loss recovery in mobile wireless networks. The MCP shifts most transport layer control policies to the mobile host side under all cases (mobile host is a sender or receiver, fixed or mobile, and so on). Therefore, mobile stations can make better transport layer control in time based on the condition of wireless link.

  6. Wireless Wonders.

    ERIC Educational Resources Information Center

    George, Katherine L.

    1995-01-01

    Cellular phones are becoming indispensable to school employees. There are three types: mobile, transportable, and hand-held, pocket-sized phones. Conversion from analog to digital technology has improved service and gained new customers. A Texas junior high school's new minicellular system allows teachers phone access to parents and has improved…

  7. Management: Global positioning and wireless dispatching

    SciTech Connect

    Wood, M.

    1996-02-01

    Over the last several years, my company has been supplying many service companies with wireless dispatching solutions. Recently the impact of the system has been greatly increased with the introduction of a GPS (Global Position Systems) interface. This adds visual recognition as to the whereabouts of each vehicle within the customer service area. The only equipment required in the field for GPS is a transmit/receive device and a wireless modem, one mounted out of the way in the vehicle (under the seat) and a {open_quotes}hockey puck{close_quotes} size unit on the roof of the vehicle. The GPS received unit and wireless modem are used to retrieve the longitude, latitude and ground speed coordinates and transmit them back to the host system.

  8. Wireless Power Transfer

    SciTech Connect

    2013-07-22

    demand for EV rises. For vehicles that operate over a fixed route such as busses and shuttle vehicles, Wireless Power Transfer (WPT) means that a smaller battery pack can be used. In the traditional system, the battery pack is designed to accommodate the needs of the entire route or shift. With WPT the battery can be downsized because it can be charged when the vehicle stops on its route (a rental car shuttle bus, for example, can charge when it waits in the terminal and again when it waits at the rental car place. Thus the battery only needs enough charge to get to the next stop. This decrease in battery size means significant cost savings to electrify the vehicle. This technology enables efficient "opportunity charging stations" for predefined routes and planned stops reducing down time. Charging can occur in minutes. This improvement also eliminates the harmful emissions that occur in garages while buses are at idle during charging. In larger cities, dynamic charging offers an even greater impact utilizing existing infrastructure. As vehicles travel along busy freeways and interstate systems, wireless charging can occur while the vehicle is in motion. With this technology a vehicle essentially has unlimited electric range while using a relatively small battery pack. In-motion charging stations use vehicle sensors to alert the driver. Traveling at normal speeds, sensors establish in-motion charging. WPT transmit pads sequentially energize to the negotiated power level based on vehicle speed and its requested charging energy. Lower power when vehicle speed is slow and much higher power for faster moving vehicles. Vehicle to Infrastructure communications (V2I) coordinates WPT charging level according to on-board battery pack state-of-charge. V2I activates the roadway transmit pads placing them in standby mode and negotiates charging fee based on prevailing grid rate and vehicle energy demand. Dynamic charging would allow electricity to supply a very large fraction of the

  9. Wireless Power Transfer

    ScienceCinema

    None

    2016-07-12

    demand for EV rises. For vehicles that operate over a fixed route such as busses and shuttle vehicles, Wireless Power Transfer (WPT) means that a smaller battery pack can be used. In the traditional system, the battery pack is designed to accommodate the needs of the entire route or shift. With WPT the battery can be downsized because it can be charged when the vehicle stops on its route (a rental car shuttle bus, for example, can charge when it waits in the terminal and again when it waits at the rental car place. Thus the battery only needs enough charge to get to the next stop. This decrease in battery size means significant cost savings to electrify the vehicle. This technology enables efficient "opportunity charging stations" for predefined routes and planned stops reducing down time. Charging can occur in minutes. This improvement also eliminates the harmful emissions that occur in garages while buses are at idle during charging. In larger cities, dynamic charging offers an even greater impact utilizing existing infrastructure. As vehicles travel along busy freeways and interstate systems, wireless charging can occur while the vehicle is in motion. With this technology a vehicle essentially has unlimited electric range while using a relatively small battery pack. In-motion charging stations use vehicle sensors to alert the driver. Traveling at normal speeds, sensors establish in-motion charging. WPT transmit pads sequentially energize to the negotiated power level based on vehicle speed and its requested charging energy. Lower power when vehicle speed is slow and much higher power for faster moving vehicles. Vehicle to Infrastructure communications (V2I) coordinates WPT charging level according to on-board battery pack state-of-charge. V2I activates the roadway transmit pads placing them in standby mode and negotiates charging fee based on prevailing grid rate and vehicle energy demand. Dynamic charging would allow electricity to supply a very large fraction of the

  10. Mixing the Emic and Etic Perspectives: A Study Exploring Development of Fixed-Answer Questions to Measure In-Service Teachers' Technological Pedagogical Content Knowledge

    ERIC Educational Resources Information Center

    Robertshaw, M. Brooke

    2013-01-01

    Using a sequential mixed-method methodology, this dissertation study set out to understand the emic and etic perspectives of the knowledge encompassed in the technological pedagogical content knowledge (TPACK) framework and to develop fixed-answer questions based on that knowledge. While there have been many studies examining ways to measure TPACK…

  11. Intrusion detection and monitoring for wireless networks.

    SciTech Connect

    Thomas, Eric D.; Van Randwyk, Jamie A.; Lee, Erik J.; Stephano, Amanda; Tabriz, Parisa; Pelon, Kristen; McCoy, Damon (University of Colorado, Boulder); Lodato, Mark; Hemingway, Franklin; Custer, Ryan P.; Averin, Dimitry; Franklin, Jason; Kilman, Dominique Marie

    2005-11-01

    Wireless computer networks are increasing exponentially around the world. They are being implemented in both the unlicensed radio frequency (RF) spectrum (IEEE 802.11a/b/g) and the licensed spectrum (e.g., Firetide [1] and Motorola Canopy [2]). Wireless networks operating in the unlicensed spectrum are by far the most popular wireless computer networks in existence. The open (i.e., proprietary) nature of the IEEE 802.11 protocols and the availability of ''free'' RF spectrum have encouraged many producers of enterprise and common off-the-shelf (COTS) computer networking equipment to jump into the wireless arena. Competition between these companies has driven down the price of 802.11 wireless networking equipment and has improved user experiences with such equipment. The end result has been an increased adoption of the equipment by businesses and consumers, the establishment of the Wi-Fi Alliance [3], and widespread use of the Alliance's ''Wi-Fi'' moniker to describe these networks. Consumers use 802.11 equipment at home to reduce the burden of running wires in existing construction, facilitate the sharing of broadband Internet services with roommates or neighbors, and increase their range of ''connectedness''. Private businesses and government entities (at all levels) are deploying wireless networks to reduce wiring costs, increase employee mobility, enable non-employees to access the Internet, and create an added revenue stream to their existing business models (coffee houses, airports, hotels, etc.). Municipalities (Philadelphia; San Francisco; Grand Haven, MI) are deploying wireless networks so they can bring broadband Internet access to places lacking such access; offer limited-speed broadband access to impoverished communities; offer broadband in places, such as marinas and state parks, that are passed over by traditional broadband providers; and provide themselves with higher quality, more complete network coverage for use by emergency responders and other

  12. Wireless Mesh Networks

    NASA Astrophysics Data System (ADS)

    Ishmael, Johnathan; Race, Nicholas

    Wireless Mesh Networks have emerged as an important technology in building next-generation networks. They are seen to have a range of benefits over traditional wired and wireless networks including low deployment costs, high scalability and resiliency to faults. Moreover, Wireless Mesh Networks (WMNs) are often described as being autonomic with self-* (healing and configuration) properties and their popularity has grown both as a research platform and as a commercially exploitable technology.

  13. Cross-layer optimization for wireless video communication

    NASA Astrophysics Data System (ADS)

    Wu, Dapeng; He, Zhihai

    2007-01-01

    With the rapid growth of wireless networks and increasing popularity of portable video devices, wireless video communication is poised to become the enabling technology for many multimedia applications over wireless networks. Real-time wireless video transmission typically has requirements on quality of service (QoS). However, wireless channels are unreliable and the channel capacities are time-varying, which may cause severe degradation to video presentation quality. In addition, for portable devices, video compression and wireless transmission are tightly coupled through the constraints on data rate, power, and delay. These issues make it particularly challenging to design an efficient real-time video compression and wireless transmission system on a portable device. In this paper, we take a cross-layer approach to this problem; our objective is to maximize the video quality under the constraints of resource and delay. Specifically, we minimize the end-to-end video distortion under the constraints of resource and delay, over the parameters in physical, link, and application (video) layers. This formulation is general and capable of capturing the fundamental aspects of the design of wireless video communication systems. Based on this formulation, we study how the resources could be intelligently allocated to maximize the video quality and analyze the performance limits of the wireless video communication system under resource constraints.

  14. Wireless security in mobile health.

    PubMed

    Osunmuyiwa, Olufolabi; Ulusoy, Ali Hakan

    2012-12-01

    Mobile health (m-health) is an extremely broad term that embraces mobile communication in the health sector and data packaging. The four broad categories of wireless networks are wireless personal area network, wireless metropolitan area network, wireless wide area network, and wireless local area network. Wireless local area network is the most notable of the wireless networking tools obtainable in the health sector. Transfer of delicate and critical information on radio frequencies should be secure, and the right to use must be meticulous. This article covers the business opportunities in m-health, threats faced by wireless networks in hospitals, and methods of mitigating these threats.

  15. Fixed Access Network Sharing

    NASA Astrophysics Data System (ADS)

    Cornaglia, Bruno; Young, Gavin; Marchetta, Antonio

    2015-12-01

    Fixed broadband network deployments are moving inexorably to the use of Next Generation Access (NGA) technologies and architectures. These NGA deployments involve building fiber infrastructure increasingly closer to the customer in order to increase the proportion of fiber on the customer's access connection (Fibre-To-The-Home/Building/Door/Cabinet… i.e. FTTx). This increases the speed of services that can be sold and will be increasingly required to meet the demands of new generations of video services as we evolve from HDTV to "Ultra-HD TV" with 4k and 8k lines of video resolution. However, building fiber access networks is a costly endeavor. It requires significant capital in order to cover any significant geographic coverage. Hence many companies are forming partnerships and joint-ventures in order to share the NGA network construction costs. One form of such a partnership involves two companies agreeing to each build to cover a certain geographic area and then "cross-selling" NGA products to each other in order to access customers within their partner's footprint (NGA coverage area). This is tantamount to a bi-lateral wholesale partnership. The concept of Fixed Access Network Sharing (FANS) is to address the possibility of sharing infrastructure with a high degree of flexibility for all network operators involved. By providing greater configuration control over the NGA network infrastructure, the service provider has a greater ability to define the network and hence to define their product capabilities at the active layer. This gives the service provider partners greater product development autonomy plus the ability to differentiate from each other at the active network layer.

  16. Implementation of Wireless Networks in Rural Areas

    DTIC Science & Technology

    2004-06-01

    access, public telephone service and fax lines to certain rural areas ( Unimas , 2004). 2. Advantages of Wireless Networking in Rural Areas With...648). Kuching. UNIMAS (2004). e-Bario Homepage: Strategy. Retrieved April 5, 2004, from http://www.unimas.my/ebario/Strategy_index.htm Cisco

  17. Clock Synchronization for Multihop Wireless Sensor Networks

    ERIC Educational Resources Information Center

    Solis Robles, Roberto

    2009-01-01

    In wireless sensor networks, more so generally than in other types of distributed systems, clock synchronization is crucial since by having this service available, several applications such as media access protocols, object tracking, or data fusion, would improve their performance. In this dissertation, we propose a set of algorithms to achieve…

  18. Clock Synchronization for Multihop Wireless Sensor Networks

    ERIC Educational Resources Information Center

    Solis Robles, Roberto

    2009-01-01

    In wireless sensor networks, more so generally than in other types of distributed systems, clock synchronization is crucial since by having this service available, several applications such as media access protocols, object tracking, or data fusion, would improve their performance. In this dissertation, we propose a set of algorithms to achieve…

  19. High Fidelity Simulations of Large-Scale Wireless Networks

    SciTech Connect

    Onunkwo, Uzoma; Benz, Zachary

    2015-11-01

    The worldwide proliferation of wireless connected devices continues to accelerate. There are 10s of billions of wireless links across the planet with an additional explosion of new wireless usage anticipated as the Internet of Things develops. Wireless technologies do not only provide convenience for mobile applications, but are also extremely cost-effective to deploy. Thus, this trend towards wireless connectivity will only continue and Sandia must develop the necessary simulation technology to proactively analyze the associated emerging vulnerabilities. Wireless networks are marked by mobility and proximity-based connectivity. The de facto standard for exploratory studies of wireless networks is discrete event simulations (DES). However, the simulation of large-scale wireless networks is extremely difficult due to prohibitively large turnaround time. A path forward is to expedite simulations with parallel discrete event simulation (PDES) techniques. The mobility and distance-based connectivity associated with wireless simulations, however, typically doom PDES and fail to scale (e.g., OPNET and ns-3 simulators). We propose a PDES-based tool aimed at reducing the communication overhead between processors. The proposed solution will use light-weight processes to dynamically distribute computation workload while mitigating communication overhead associated with synchronizations. This work is vital to the analytics and validation capabilities of simulation and emulation at Sandia. We have years of experience in Sandia’s simulation and emulation projects (e.g., MINIMEGA and FIREWHEEL). Sandia’s current highly-regarded capabilities in large-scale emulations have focused on wired networks, where two assumptions prevent scalable wireless studies: (a) the connections between objects are mostly static and (b) the nodes have fixed locations.

  20. Error resilient interactive video streaming over wireless networks

    NASA Astrophysics Data System (ADS)

    Hadjinicolaou, Marios G.; Psannis, Kostas E.; Ishibashi, Yutaka

    2007-09-01

    This paper presents an efficient approach for supporting wireless video full interactive services. One of the main goals of wireless video multicast services is to provide priority including dedicated bandwidth, controlled jitter (required by some real-time and interactive traffic), and improved loss characteristics. The proposed method is based on storing multiple differently encoded versions of the normal/interactive video streams at the server. The corresponding video streams are obtained by encoding the original uncompressed video file as a sequence of I-P(I) frames and I-P(M) frames using different GOP (Group Of Pictures) pattern. Mechanisms for controlling the normal/interactive request are also presented and their effectiveness is assessed through extensive simulations. Wireless normal/interactive video services are supported with considerably reduced additional delay and acceptable visual quality at the wireless client-end.

  1. Packet Controller For Wireless Headset

    NASA Technical Reports Server (NTRS)

    Christensen, Kurt K.; Swanson, Richard J.

    1993-01-01

    Packet-message controller implements communications protocol of network of wireless headsets. Designed for headset application, readily adapted to other uses; slight modification enables controller to implement Integrated Services Digital Network (ISDN) X.25 protocol, giving far-reaching applications in telecommunications. Circuit converts continuous voice signals into digital packets of data and vice versa. Operates in master or slave mode. Controller reduced to single complementary metal oxide/semiconductor integrated-circuit chip. Occupies minimal space in headset and consumes little power, extending life of headset battery.

  2. Collaboration in a Wireless Grid Innovation Testbed by Virtual Consortium

    NASA Astrophysics Data System (ADS)

    Treglia, Joseph; Ramnarine-Rieks, Angela; McKnight, Lee

    This paper describes the formation of the Wireless Grid Innovation Testbed (WGiT) coordinated by a virtual consortium involving academic and non-academic entities. Syracuse University and Virginia Tech are primary university partners with several other academic, government, and corporate partners. Objectives include: 1) coordinating knowledge sharing, 2) defining key parameters for wireless grids network applications, 3) dynamically connecting wired and wireless devices, content and users, 4) linking to VT-CORNET, Virginia Tech Cognitive Radio Network Testbed, 5) forming ad hoc networks or grids of mobile and fixed devices without a dedicated server, 6) deepening understanding of wireless grid application, device, network, user and market behavior through academic, trade and popular publications including online media, 7) identifying policy that may enable evaluated innovations to enter US and international markets and 8) implementation and evaluation of the international virtual collaborative process.

  3. Warming Up to Wireless

    ERIC Educational Resources Information Center

    Milner, Jacob

    2005-01-01

    In districts big and small across the U.S., students, teachers, and administrators alike have come to appreciate the benefits of wireless technology. Because the technology delivers Internet signals on airborne radio frequencies, wireless networking allows users of all portable devices to move freely on a school's campus and stay connected to the…

  4. Warming Up to Wireless

    ERIC Educational Resources Information Center

    Milner, Jacob

    2005-01-01

    In districts big and small across the U.S., students, teachers, and administrators alike have come to appreciate the benefits of wireless technology. Because the technology delivers Internet signals on airborne radio frequencies, wireless networking allows users of all portable devices to move freely on a school's campus and stay connected to the…

  5. Debate: Wired versus Wireless.

    ERIC Educational Resources Information Center

    Meeks, Glenn; Nair, Prakash

    2000-01-01

    Debates the issue of investing in wiring schools for desktop computer networks versus using laptops and wireless networks. Included are cost considerations and the value of technology for learning. Suggestions include using wireless networks for existing schools, hardwiring computers for new construction, and not using computers for elementary…

  6. 76 FR 23713 - Wireless E911 Location Accuracy Requirements

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-28

    ... carriers using network-based technologies to provide Enhanced 911 (E911) Phase II service may exclude from... carriers wireless carriers using handset-based technologies to provide Enhanced 911 (E911) Phase II service... confidence and uncertainty levels in a county or PSAP service area, ongoing accuracy shall be monitored...

  7. IEEE 802.11 Wireless LAN Security White Paper

    SciTech Connect

    King, J

    2001-10-22

    Given the increased productivity and growing popularity of wireless communications in general, and wireless data communications in particular, this paper outlines the protocols, security implications, and architectures of IEEE Std. 802.11-1999 wireless LANs (WLANs) and makes recommendations regarding a phased implementation of WLANs at LLNL. This project is driven by the need for convenient and secure access to the Internet for Laboratory visitors and to the internal network for Laboratory employees. A solid architecture designed with a priority on security will allow LLNL to offer network access in areas where it is traditionally hard to deploy wired networks. It will also enable such services as wireless access for inventory control and convenient network access for conference rooms around LLNL. Wireless network access has the potential to increase productivity by enabling instant access to information.

  8. NASA Lunar Base Wireless System Propagation Analysis

    NASA Technical Reports Server (NTRS)

    Hwu, Shian U.; Upanavage, Matthew; Sham, Catherine C.

    2007-01-01

    There have been many radio wave propagation studies using both experimental and theoretical techniques over the recent years. However, most of studies have been in support of commercial cellular phone wireless applications. The signal frequencies are mostly at the commercial cellular and Personal Communications Service bands. The antenna configurations are mostly one on a high tower and one near the ground to simulate communications between a cellular base station and a mobile unit. There are great interests in wireless communication and sensor systems for NASA lunar missions because of the emerging importance of establishing permanent lunar human exploration bases. Because of the specific lunar terrain geometries and RF frequencies of interest to the NASA missions, much of the published literature for the commercial cellular and PCS bands of 900 and 1800 MHz may not be directly applicable to the lunar base wireless system and environment. There are various communication and sensor configurations required to support all elements of a lunar base. For example, the communications between astronauts, between astronauts and the lunar vehicles, between lunar vehicles and satellites on the lunar orbits. There are also various wireless sensor systems among scientific, experimental sensors and data collection ground stations. This presentation illustrates the propagation analysis of the lunar wireless communication and sensor systems taking into account the three dimensional terrain multipath effects. It is observed that the propagation characteristics are significantly affected by the presence of the lunar terrain. The obtained results indicate the lunar surface material, terrain geometry and antenna location are the important factors affecting the propagation characteristics of the lunar wireless systems. The path loss can be much more severe than the free space propagation and is greatly affected by the antenna height, surface material and operating frequency. The

  9. Wireless communication with chaos.

    PubMed

    Ren, Hai-Peng; Baptista, Murilo S; Grebogi, Celso

    2013-05-03

    The modern world fully relies on wireless communication. Because of intrinsic physical constraints of the wireless physical media (multipath, damping, and filtering), signals carrying information are strongly modified, preventing information from being transmitted with a high bit rate. We show that, though a chaotic signal is strongly modified by the wireless physical media, its Lyapunov exponents remain unaltered, suggesting that the information transmitted is not modified by the channel. For some particular chaotic signals, we have indeed proved that the dynamic description of both the transmitted and the received signals is identical and shown that the capacity of the chaos-based wireless channel is unaffected by the multipath propagation of the physical media. These physical properties of chaotic signals warrant an effective chaos-based wireless communication system.

  10. Transport Protocols for Wireless Mesh Networks

    NASA Astrophysics Data System (ADS)

    Eddie Law, K. L.

    Transmission control protocol (TCP) provides reliable connection-oriented services between any two end systems on the Internet. With TCP congestion control algorithm, multiple TCP connections can share network and link resources simultaneously. These TCP congestion control mechanisms have been operating effectively in wired networks. However, performance of TCP connections degrades rapidly in wireless and lossy networks. To sustain the throughput performance of TCP connections in wireless networks, design modifications may be required accordingly in the TCP flow control algorithm, and potentially, in association with other protocols in other layers for proper adaptations. In this chapter, we explain the limitations of the latest TCP congestion control algorithm, and then review some popular designs for TCP connections to operate effectively in wireless mesh network infrastructure.

  11. Optical wireless connected objects for healthcare.

    PubMed

    Toumieux, Pascal; Chevalier, Ludovic; Sahuguède, Stéphanie; Julien-Vergonjanne, Anne

    2015-10-01

    In this Letter the authors explore the communication capabilities of optical wireless technology for a wearable device dedicated to healthcare application. In an indoor environment sensible to electromagnetic perturbations such as a hospital, the use of optical wireless links can permit reducing the amount of radio frequencies in the patient environment. Moreover, this technology presents the advantage to be secure, low-cost and easy to deploy. On the basis of commercially available components, a custom-made wearable device is presented, which allows optical wireless transmission of accelerometer data in the context of physical activity supervision of post-stroke patients in hospital. Considering patient mobility, the experimental performance is established in terms of packet loss as a function of the number of receivers fixed to the ceiling. The results permit to conclude that optical wireless links can be used to perform such mobile remote monitoring applications. Moreover, based on the measurements obtained with one receiver, it is possible to theoretically determine the performance according to the number of receivers to be deployed.

  12. Optical wireless connected objects for healthcare

    PubMed Central

    Toumieux, Pascal; Chevalier, Ludovic; Sahuguède, Stéphanie

    2015-01-01

    In this Letter the authors explore the communication capabilities of optical wireless technology for a wearable device dedicated to healthcare application. In an indoor environment sensible to electromagnetic perturbations such as a hospital, the use of optical wireless links can permit reducing the amount of radio frequencies in the patient environment. Moreover, this technology presents the advantage to be secure, low-cost and easy to deploy. On the basis of commercially available components, a custom-made wearable device is presented, which allows optical wireless transmission of accelerometer data in the context of physical activity supervision of post-stroke patients in hospital. Considering patient mobility, the experimental performance is established in terms of packet loss as a function of the number of receivers fixed to the ceiling. The results permit to conclude that optical wireless links can be used to perform such mobile remote monitoring applications. Moreover, based on the measurements obtained with one receiver, it is possible to theoretically determine the performance according to the number of receivers to be deployed. PMID:26609417

  13. 47 CFR 80.387 - Frequencies for Alaska fixed stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Frequencies for Alaska fixed stations. 80.387... SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Alaska Fixed Stations § 80.387 Frequencies for Alaska fixed stations. (a) The carrier frequencies listed in (b) of this section are assignable for point...

  14. 47 CFR 80.387 - Frequencies for Alaska fixed stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies for Alaska fixed stations. 80.387... SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Alaska Fixed Stations § 80.387 Frequencies for Alaska fixed stations. (a) The carrier frequencies listed in (b) of this section are assignable for point...

  15. 47 CFR 101.125 - Temporary fixed antenna height restrictions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Temporary fixed antenna height restrictions. 101.125 Section 101.125 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna...

  16. 47 CFR 101.125 - Temporary fixed antenna height restrictions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Temporary fixed antenna height restrictions. 101.125 Section 101.125 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna...

  17. 47 CFR 101.125 - Temporary fixed antenna height restrictions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the...

  18. 47 CFR 101.125 - Temporary fixed antenna height restrictions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the...

  19. 47 CFR 101.125 - Temporary fixed antenna height restrictions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the...

  20. 47 CFR 80.381 - Frequencies for operational fixed stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Frequencies for operational fixed stations. 80... RADIO SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Operational Fixed Stations § 80.381 Frequencies for operational fixed stations. The following carrier frequencies in the 72-76 MHz band are...

  1. 47 CFR 80.381 - Frequencies for operational fixed stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Frequencies for operational fixed stations. 80... RADIO SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Operational Fixed Stations § 80.381 Frequencies for operational fixed stations. The following carrier frequencies in the 72-76 MHz band are...

  2. 47 CFR 80.381 - Frequencies for operational fixed stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequencies for operational fixed stations. 80... RADIO SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Operational Fixed Stations § 80.381 Frequencies for operational fixed stations. The following carrier frequencies in the 72-76 MHz band are...

  3. 47 CFR 22.1031 - Temporary fixed stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Temporary fixed stations. 22.1031 Section 22... MOBILE SERVICES Offshore Radiotelephone Service § 22.1031 Temporary fixed stations. The FCC may, upon proper application therefor, authorize the construction and operation of temporary fixed stations in the...

  4. 47 CFR 22.1031 - Temporary fixed stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Temporary fixed stations. 22.1031 Section 22... MOBILE SERVICES Offshore Radiotelephone Service § 22.1031 Temporary fixed stations. The FCC may, upon proper application therefor, authorize the construction and operation of temporary fixed stations in the...

  5. 47 CFR 80.387 - Frequencies for Alaska fixed stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Frequencies for Alaska fixed stations. 80.387... SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Alaska Fixed Stations § 80.387 Frequencies for Alaska fixed stations. (a) The carrier frequencies listed in (b) of this section are assignable for point...

  6. 47 CFR 80.387 - Frequencies for Alaska fixed stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Frequencies for Alaska fixed stations. 80.387... SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Alaska Fixed Stations § 80.387 Frequencies for Alaska fixed stations. (a) The carrier frequencies listed in (b) of this section are assignable for point...

  7. 47 CFR 80.387 - Frequencies for Alaska fixed stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequencies for Alaska fixed stations. 80.387... SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Alaska Fixed Stations § 80.387 Frequencies for Alaska fixed stations. (a) The carrier frequencies listed in (b) of this section are assignable for point...

  8. 47 CFR 22.1031 - Temporary fixed stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Temporary fixed stations. 22.1031 Section 22... MOBILE SERVICES Offshore Radiotelephone Service § 22.1031 Temporary fixed stations. The FCC may, upon proper application therefor, authorize the construction and operation of temporary fixed stations in the...

  9. Wireless quantified reflex device

    NASA Astrophysics Data System (ADS)

    Lemoyne, Robert Charles

    The deep tendon reflex is a fundamental aspect of a neurological examination. The two major parameters of the tendon reflex are response and latency, which are presently evaluated qualitatively during a neurological examination. The reflex loop is capable of providing insight for the status and therapy response of both upper and lower motor neuron syndromes. Attempts have been made to ascertain reflex response and latency, however these systems are relatively complex, resource intensive, with issues of consistent and reliable accuracy. The solution presented is a wireless quantified reflex device using tandem three dimensional wireless accelerometers to obtain response based on acceleration waveform amplitude and latency derived from temporal acceleration waveform disparity. Three specific aims have been established for the proposed wireless quantified reflex device: 1. Demonstrate the wireless quantified reflex device is reliably capable of ascertaining quantified reflex response and latency using a quantified input. 2. Evaluate the precision of the device using an artificial reflex system. 3.Conduct a longitudinal study respective of subjects with healthy patellar tendon reflexes, using the wireless quantified reflex evaluation device to obtain quantified reflex response and latency. Aim 1 has led to the steady evolution of the wireless quantified reflex device from a singular two dimensional wireless accelerometer capable of measuring reflex response to a tandem three dimensional wireless accelerometer capable of reliably measuring reflex response and latency. The hypothesis for aim 1 is that a reflex quantification device can be established for reliably measuring reflex response and latency for the patellar tendon reflex, comprised of an integrated system of wireless three dimensional MEMS accelerometers. Aim 2 further emphasized the reliability of the wireless quantified reflex device by evaluating an artificial reflex system. The hypothesis for aim 2 is that

  10. Wireless nanosensor network system

    NASA Astrophysics Data System (ADS)

    Oh, Sechang; Kwon, Hyukjun; Kegley, Lauren; Yoon, Hargsoon; Varadan, Vijay K.

    2009-03-01

    Many types of wireless modules are being developed to enhance wireless performance with low power consumption, compact size, high data rates, and wide range coverage. However trade-offs must be taken into consideration in order to satisfy all aspects of wireless performance. For example, in order to increase the data rate and wide range coverage, power consumption should be sacrificed. To overcome these drawbacks, the paper presents a wireless client module which offers low power consumption along with a wireless receiver module that has the strength to provide high data rates and wide range coverage. Adopting Zigbee protocol in the wireless client module, the power consumption performance is enhanced so that it plays a part of the mobile device. On the other hand, the wireless receiver module, as adopting Zigbee and Wi-Fi protocol, provides high data rate, wide range coverage, and easy connection to the existing Internet network so that it plays a part of the portable device. This module demonstrates monitoring of gait analysis. The results show that the sensing data being measured can be monitored in any remote place with access to the Internet network.

  11. Orbit-spectrum sharing between the fixed-satellite and broadcasting-satellite services with applications to 12 GHz domestic systems

    NASA Technical Reports Server (NTRS)

    Reinhart, E. E.

    1974-01-01

    A systematic, tutorial analysis of the general problem of orbit-spectrum sharing among inhomogeneous satellite system is presented. Emphasis is placed on extrapolating and applying the available data on rain attenuation and on reconciling differences in the results of various measurements of the subjective effects of interference on television picture quality. An analytic method is presented for determining the approximate values of the intersatellite spacings required to keep mutual interference levels within prescribed limits when many dissimilar satellites share the orbit. A computer model was developed for assessing the interference compatibility of arbitrary configurations of large numbers of geostationary satellite systems. It is concluded that the band from 11.7 c GHz can be shared effectively by broadcasting-satellite and fixed-satellite systems. Recommendations for future study are included.

  12. Software-defined Radio Based Measurement Platform for Wireless Networks.

    PubMed

    Chao, I-Chun; Lee, Kang B; Candell, Richard; Proctor, Frederick; Shen, Chien-Chung; Lin, Shinn-Yan

    2015-10-01

    End-to-end latency is critical to many distributed applications and services that are based on computer networks. There has been a dramatic push to adopt wireless networking technologies and protocols (such as WiFi, ZigBee, WirelessHART, Bluetooth, ISA100.11a, etc.) into time-critical applications. Examples of such applications include industrial automation, telecommunications, power utility, and financial services. While performance measurement of wired networks has been extensively studied, measuring and quantifying the performance of wireless networks face new challenges and demand different approaches and techniques. In this paper, we describe the design of a measurement platform based on the technologies of software-defined radio (SDR) and IEEE 1588 Precision Time Protocol (PTP) for evaluating the performance of wireless networks.

  13. Software-defined Radio Based Measurement Platform for Wireless Networks

    PubMed Central

    Chao, I-Chun; Lee, Kang B.; Candell, Richard; Proctor, Frederick; Shen, Chien-Chung; Lin, Shinn-Yan

    2015-01-01

    End-to-end latency is critical to many distributed applications and services that are based on computer networks. There has been a dramatic push to adopt wireless networking technologies and protocols (such as WiFi, ZigBee, WirelessHART, Bluetooth, ISA100.11a, etc.) into time-critical applications. Examples of such applications include industrial automation, telecommunications, power utility, and financial services. While performance measurement of wired networks has been extensively studied, measuring and quantifying the performance of wireless networks face new challenges and demand different approaches and techniques. In this paper, we describe the design of a measurement platform based on the technologies of software-defined radio (SDR) and IEEE 1588 Precision Time Protocol (PTP) for evaluating the performance of wireless networks. PMID:27891210

  14. 47 CFR 25.146 - Licensing and operating rules for the non-geostationary orbit Fixed-Satellite Service in the 10.7...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the 10.7-14.5 GHz bands. The technical information shall demonstrate that the proposed NGSO FSS system... Service (NGSO FSS) system in the 10.7-14.5 GHz bands. The technical information shall demonstrate that the... may request at any time additional information from the NGSO FSS system applicant or licensee...

  15. Wireless Sensor Networks: Monitoring and Control

    SciTech Connect

    Hastbacka, Mildred; Ponoum, Ratcharit; Bouza, Antonio

    2013-05-31

    The article discusses wireless sensor technologies for building energy monitoring and control. This article, also, addresses wireless sensor networks as well as benefits and challenges of using wireless sensors. The energy savings and market potential of wireless sensors are reviewed.

  16. Performance evaluation of TCP implementations in wireless networks

    NASA Astrophysics Data System (ADS)

    ElAarag, Hala; Bassiouni, Mostafa A.

    1999-06-01

    The performance of TCP has been well tuned for traditional networks made up of wired links and stationary hosts. Mobile networks, however, differs from conventional wired computer networks and usually suffer from high bit error rates and frequent disconnections due to handoffs. In this paper, we present simulation results for the performance of various TCP implementations in the presence of a wireless link. To concentrate on the mobility and reliability aspects of the wireless connection, our simulation tests used sufficiently large buffer sizes in the fixed host and the base station of the TCP connection. The results show that throughput of the TCP connection is largely influenced by the link-up period of the wireless link. By varying the link-up and the link- down periods, it is possible to obtain better throughput at higher disconnection probability. For example, the throughput of TCP Reno with disconnection probability of 28.6% and a link-up period of 5 is better than the throughput with disconnection probability of 9% and a link- up period of less than 3. The paper presents timing graphs tracing the movement of packets and acknowledgements between the fixed and mobile hosts. Dropped packets or acknowledgements shown in these graphs are the result of mobile disconnection or wireless bit errors and not because of buffer congestion. Unlike wired networks, Reno TCP was found to perform better than Sack in the wireless mobile environment.

  17. 'It is not a quick fix' structural and contextual issues that affect implementation of integrated health and well-being services: a qualitative study from North East England.

    PubMed

    Cheetham, M; Visram, S; Rushmer, R; Greig, G; Gibson, E; Khazaeli, B; Wiseman, A

    2017-09-04

    The objective of this article is to examine the factors affecting the design, commissioning and delivery of integrated health and well-being services (IHWSs), which seek to address multiple health-related behaviours, improve well-being and tackle health inequalities using holistic approaches. Qualitative studies embedded within iterative process evaluations. Semi-structured interviews conducted with 16 key informants as part of two separate evaluations of IHWSs in North East England, supplemented by informal observations of service delivery. Transcripts and fieldnotes were analysed thematically. The study findings identify a challenging organisational context in which to implement innovative service redesign, as a result of budget cuts and changes in NHS and local authority capacity. Pressures to demonstrate outcomes affected the ability to negotiate the practicalities of joint working. Progress is at risk of being undermined by pressures to disinvest before the long-term benefits to population health and well-being are realised. The findings raise important questions about contract management and relationships between commissioners and providers involved in implementing these new ways of working. These findings provide useful learning in terms of the delivery and commissioning of similar IHWSs, contributing to understanding of the benefits and challenges of this model of working. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  18. Wireless Networks: New Meaning to Ubiquitous Computing.

    ERIC Educational Resources Information Center

    Drew, Wilfred, Jr.

    2003-01-01

    Discusses the use of wireless technology in academic libraries. Topics include wireless networks; standards (IEEE 802.11); wired versus wireless; why libraries implement wireless technology; wireless local area networks (WLANs); WLAN security; examples of wireless use at Indiana State University and Morrisville College (New York); and useful…

  19. Wireless Networks: New Meaning to Ubiquitous Computing.

    ERIC Educational Resources Information Center

    Drew, Wilfred, Jr.

    2003-01-01

    Discusses the use of wireless technology in academic libraries. Topics include wireless networks; standards (IEEE 802.11); wired versus wireless; why libraries implement wireless technology; wireless local area networks (WLANs); WLAN security; examples of wireless use at Indiana State University and Morrisville College (New York); and useful…

  20. 47 CFR 101.815 - Stations at temporary fixed locations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Stations at temporary fixed locations. 101.815 Section 101.815 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.815 Stations at temporary...

  1. 47 CFR 101.815 - Stations at temporary fixed locations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Stations at temporary fixed locations. 101.815 Section 101.815 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.815 Stations at...

  2. 47 CFR 101.815 - Stations at temporary fixed locations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Stations at temporary fixed locations. 101.815 Section 101.815 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.815 Stations at...

  3. SITRUS: Semantic Infrastructure for Wireless Sensor Networks.

    PubMed

    Bispo, Kalil A; Rosa, Nelson S; Cunha, Paulo R F

    2015-10-29

    Wireless sensor networks (WSNs) are made up of nodes with limited resources, such as processing, bandwidth, memory and, most importantly, energy. For this reason, it is essential that WSNs always work to reduce the power consumption as much as possible in order to maximize its lifetime. In this context, this paper presents SITRUS (semantic infrastructure for wireless sensor networks), which aims to reduce the power consumption of WSN nodes using ontologies. SITRUS consists of two major parts: a message-oriented middleware responsible for both an oriented message communication service and a reconfiguration service; and a semantic information processing module whose purpose is to generate a semantic database that provides the basis to decide whether a WSN node needs to be reconfigurated or not. In order to evaluate the proposed solution, we carried out an experimental evaluation to assess the power consumption and memory usage of WSN applications built atop SITRUS.

  4. SITRUS: Semantic Infrastructure for Wireless Sensor Networks

    PubMed Central

    Bispo, Kalil A.; Rosa, Nelson S.; Cunha, Paulo R. F.

    2015-01-01

    Wireless sensor networks (WSNs) are made up of nodes with limited resources, such as processing, bandwidth, memory and, most importantly, energy. For this reason, it is essential that WSNs always work to reduce the power consumption as much as possible in order to maximize its lifetime. In this context, this paper presents SITRUS (semantic infrastructure for wireless sensor networks), which aims to reduce the power consumption of WSN nodes using ontologies. SITRUS consists of two major parts: a message-oriented middleware responsible for both an oriented message communication service and a reconfiguration service; and a semantic information processing module whose purpose is to generate a semantic database that provides the basis to decide whether a WSN node needs to be reconfigurated or not. In order to evaluate the proposed solution, we carried out an experimental evaluation to assess the power consumption and memory usage of WSN applications built atop SITRUS. PMID:26528974

  5. A Wireless World: Charles County Public Schools Makes Wireless Universal

    ERIC Educational Resources Information Center

    Hoffman, Richard

    2007-01-01

    Wireless connectivity in schools is all the rage, and many school systems have at least gotten their feet wet with a wireless lab or a few portable laptop carts. But Bijaya Devkota, the chief information officer of Charles County Public Schools, has done what many school systems only dream of--implemented universal wireless access throughout his…

  6. An 802.11 n wireless local area network transmission scheme for wireless telemedicine applications.

    PubMed

    Lin, C F; Hung, S I; Chiang, I H

    2010-10-01

    In this paper, an 802.11 n transmission scheme is proposed for wireless telemedicine applications. IEEE 802.11n standards, a power assignment strategy, space-time block coding (STBC), and an object composition Petri net (OCPN) model are adopted. With the proposed wireless system, G.729 audio bit streams, Joint Photographic Experts Group 2000 (JPEG 2000) clinical images, and Moving Picture Experts Group 4 (MPEG-4) video bit streams achieve a transmission bit error rate (BER) of 10-7, 10-4, and 103 simultaneously. The proposed system meets the requirements prescribed for wireless telemedicine applications. An essential feature of this proposed transmission scheme is that clinical information that requires a high quality of service (QoS) is transmitted at a high power transmission rate with significant error protection. For maximizing resource utilization and minimizing the total transmission power, STBC and adaptive modulation techniques are used in the proposed 802.11 n wireless telemedicine system. Further, low power, direct mapping (DM), low-error protection scheme, and high-level modulation are adopted for messages that can tolerate a high BER. With the proposed transmission scheme, the required reliability of communication can be achieved. Our simulation results have shown that the proposed 802.11 n transmission scheme can be used for developing effective wireless telemedicine systems.

  7. Mobile Robot Positioning with 433-MHz Wireless Motes with Varying Transmission Powers and a Particle Filter

    PubMed Central

    Canedo-Rodriguez, Adrian; Rodriguez, Jose Manuel; Alvarez-Santos, Victor; Iglesias, Roberto; Regueiro, Carlos V.

    2015-01-01

    In wireless positioning systems, the transmitter's power is usually fixed. In this paper, we explore the use of varying transmission powers to increase the performance of a wireless localization system. To this extent, we have designed a robot positioning system based on wireless motes. Our motes use an inexpensive, low-power sub-1-GHz system-on-chip (CC1110) working in the 433-MHz ISM band. Our localization algorithm is based on a particle filter and infers the robot position by: (1) comparing the power received with the expected one; and (2) integrating the robot displacement. We demonstrate that the use of transmitters that vary their transmission power over time improves the performance of the wireless positioning system significantly, with respect to a system that uses fixed power transmitters. This opens the door for applications where the robot can localize itself actively by requesting the transmitters to change their power in real time. PMID:25942641

  8. Mobile Robot Positioning with 433-MHz Wireless Motes with Varying Transmission Powers and a Particle Filter.

    PubMed

    Canedo-Rodriguez, Adrian; Rodriguez, Jose Manuel; Alvarez-Santos, Victor; Iglesias, Roberto; Regueiro, Carlos V

    2015-04-30

    In wireless positioning systems, the transmitter's power is usually fixed. In this paper, we explore the use of varying transmission powers to increase the performance of a wireless localization system. To this extent, we have designed a robot positioning system based on wireless motes. Our motes use an inexpensive, low-power sub-1-GHz system-on-chip (CC1110) working in the 433-MHz ISM band. Our localization algorithm is based on a particle filter and infers the robot position by: (1) comparing the power received with the expected one; and (2) integrating the robot displacement. We demonstrate that the use of transmitters that vary their transmission power over time improves the performance of the wireless positioning system significantly, with respect to a system that uses fixed power transmitters. This opens the door for applications where the robot can localize itself actively by requesting the transmitters to change their power in real time.

  9. Wireless Network Security Using Randomness

    DTIC Science & Technology

    2012-06-19

    REPORT WIRELESS NETWORK SECURITY USING RANDOMNESS 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: The present invention provides systems and methods for... securing communications in a wireless network by utilizing the inherent randomness of propagation errors to enable legitimate users to dynamically...Box 12211 Research Triangle Park, NC 27709-2211 15. SUBJECT TERMS Patent, security , wireless networks, randomness Sheng Xiao, Weibo Gong

  10. Fixing Maintenance Productivity.

    ERIC Educational Resources Information Center

    Fickes, Michael

    2003-01-01

    Describes how one university's facility managers use Nextel communications technology in conjunction with a Famis Software maintenance management system to improve the productivity of its maintenance technicians. The system uses a wireless Internet connection to automate the flow of work order information to and from technicians. The key to these…

  11. Fixing Maintenance Productivity.

    ERIC Educational Resources Information Center

    Fickes, Michael

    2003-01-01

    Describes how one university's facility managers use Nextel communications technology in conjunction with a Famis Software maintenance management system to improve the productivity of its maintenance technicians. The system uses a wireless Internet connection to automate the flow of work order information to and from technicians. The key to these…

  12. Advanced modulation formats for delivery of heterogeneous wired and wireless access networks

    NASA Astrophysics Data System (ADS)

    Chow, C. W.; Yeh, C. H.

    2009-12-01

    It is believed that the integration of wired and wireless access networks (or heterogeneous network) will provide high bandwidth and flexibility for both fixed and mobile users in a single and cost-effective platform. Here, we propose and demonstrate a signal remodulated wired and wireless network with wireless signal broadcast. Dark-return-to-zero (DRZ) and polarization-shift-keying (PolSK) signals are used for the downstream wired and wireless applications respectively. At the remote antenna unit (RAU), the PolSK signal is demodulated to produce the binary-phase-shift-keying (BPSK) signal, which will be used for the wireless broadcast application. Signal remodulation is demonstrated using reflective semiconductor optical amplifier (RSOA) as a colorless reflective modulator in the optical networking unit (ONU)/RAU. The downstream signal is remodulated at the ONU/RAU to produce the non-return-to-zero (NRZ) upstream signal.

  13. 21 CFR 874.3305 - Wireless air-conduction hearing aid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Wireless air-conduction hearing aid. 874.3305 Section 874.3305 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-amplifying device, intended to compensate for impaired hearing that incorporates wireless technology in...

  14. 21 CFR 874.3305 - Wireless air-conduction hearing aid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Wireless air-conduction hearing aid. 874.3305 Section 874.3305 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-amplifying device, intended to compensate for impaired hearing that incorporates wireless technology in...

  15. Mobile Applications and 4G Wireless Networks: A Framework for Analysis

    ERIC Educational Resources Information Center

    Yang, Samuel C.

    2012-01-01

    Purpose: The use of mobile wireless data services continues to increase worldwide. New fourth-generation (4G) wireless networks can deliver data rates exceeding 2 Mbps. The purpose of this paper is to develop a framework of 4G mobile applications that utilize such high data rates and run on small form-factor devices. Design/methodology/approach:…

  16. Mobile Applications and 4G Wireless Networks: A Framework for Analysis

    ERIC Educational Resources Information Center

    Yang, Samuel C.

    2012-01-01

    Purpose: The use of mobile wireless data services continues to increase worldwide. New fourth-generation (4G) wireless networks can deliver data rates exceeding 2 Mbps. The purpose of this paper is to develop a framework of 4G mobile applications that utilize such high data rates and run on small form-factor devices. Design/methodology/approach:…

  17. Reliability of Wireless Sensor Networks

    PubMed Central

    Dâmaso, Antônio; Rosa, Nelson; Maciel, Paulo

    2014-01-01

    Wireless Sensor Networks (WSNs) consist of hundreds or thousands of sensor nodes with limited processing, storage, and battery capabilities. There are several strategies to reduce the power consumption of WSN nodes (by increasing the network lifetime) and increase the reliability of the network (by improving the WSN Quality of Service). However, there is an inherent conflict between power consumption and reliability: an increase in reliability usually leads to an increase in power consumption. For example, routing algorithms can send the same packet though different paths (multipath strategy), which it is important for reliability, but they significantly increase the WSN power consumption. In this context, this paper proposes a model for evaluating the reliability of WSNs considering the battery level as a key factor. Moreover, this model is based on routing algorithms used by WSNs. In order to evaluate the proposed models, three scenarios were considered to show the impact of the power consumption on the reliability of WSNs. PMID:25157553

  18. New packet scheduling algorithm in wireless CDMA data networks

    NASA Astrophysics Data System (ADS)

    Wang, Yu; Gao, Zhuo; Li, Shaoqian; Li, Lemin

    2002-08-01

    The future 3G/4G wireless communication systems will provide internet access for mobile users. Packet scheduling algorithms are essential for QoS of diversified data traffics and efficient utilization of radio spectrum.This paper firstly presents a new packet scheduling algorithm DSTTF under the assumption of continuous transmission rates and scheduling intervals for CDMA data networks . Then considering the constraints of discrete transmission rates and fixed scheduling intervals imposed by the practical system, P-DSTTF, a modified version of DSTTF, is brought forward. Both scheduling algorithms take into consideration of channel condition, packet size and traffic delay bounds. The extensive simulation results demonstrate that the proposed scheduling algorithms are superior to some typical ones in current research. In addition, both static and dynamic wireless channel model of multi-level link capacity are established. These channel models sketch better the characterizations of wireless channel than two state Markov model widely adopted by the current literature.

  19. Portable wireless power transmission system for video capsule endoscopy.

    PubMed

    Zhiwei, Jia; Guozheng, Yan; Bingquan, Zhu

    2014-10-01

    Wireless power transmission is considered a practical way of overcoming the power shortage of wireless capsule endoscopy (VCE). However, most patients cannot tolerate the long hours of lying in a fixed transmitting coil during diagnosis. To develop a portable wireless power transmission system for VCE, a compact transmitting coil and a portable inverter circuit driven by rechargeable batteries are proposed. The couple coils, optimized considering the stability and safety conditions, are 28 turns of transmitting coil and six strands of receiving coil. The driven circuit is designed according to the portable principle. Experiments show that the integrated system could continuously supply power to a dual-head VCE for more than 8 h at a frame rate of 30 frames per second with resolution of 320 × 240. The portable VCE exhibits potential for clinical applications, but requires further improvement and tests.

  20. Wireless physical layer security

    NASA Astrophysics Data System (ADS)

    Poor, H. Vincent; Schaefer, Rafael F.

    2017-01-01

    Security in wireless networks has traditionally been considered to be an issue to be addressed separately from the physical radio transmission aspects of wireless systems. However, with the emergence of new networking architectures that are not amenable to traditional methods of secure communication such as data encryption, there has been an increase in interest in the potential of the physical properties of the radio channel itself to provide communications security. Information theory provides a natural framework for the study of this issue, and there has been considerable recent research devoted to using this framework to develop a greater understanding of the fundamental ability of the so-called physical layer to provide security in wireless networks. Moreover, this approach is also suggestive in many cases of coding techniques that can approach fundamental limits in practice and of techniques for other security tasks such as authentication. This paper provides an overview of these developments.

  1. Wireless physical layer security

    PubMed Central

    Schaefer, Rafael F.

    2017-01-01

    Security in wireless networks has traditionally been considered to be an issue to be addressed separately from the physical radio transmission aspects of wireless systems. However, with the emergence of new networking architectures that are not amenable to traditional methods of secure communication such as data encryption, there has been an increase in interest in the potential of the physical properties of the radio channel itself to provide communications security. Information theory provides a natural framework for the study of this issue, and there has been considerable recent research devoted to using this framework to develop a greater understanding of the fundamental ability of the so-called physical layer to provide security in wireless networks. Moreover, this approach is also suggestive in many cases of coding techniques that can approach fundamental limits in practice and of techniques for other security tasks such as authentication. This paper provides an overview of these developments. PMID:28028211

  2. Wireless physical layer security.

    PubMed

    Poor, H Vincent; Schaefer, Rafael F

    2017-01-03

    Security in wireless networks has traditionally been considered to be an issue to be addressed separately from the physical radio transmission aspects of wireless systems. However, with the emergence of new networking architectures that are not amenable to traditional methods of secure communication such as data encryption, there has been an increase in interest in the potential of the physical properties of the radio channel itself to provide communications security. Information theory provides a natural framework for the study of this issue, and there has been considerable recent research devoted to using this framework to develop a greater understanding of the fundamental ability of the so-called physical layer to provide security in wireless networks. Moreover, this approach is also suggestive in many cases of coding techniques that can approach fundamental limits in practice and of techniques for other security tasks such as authentication. This paper provides an overview of these developments.

  3. Terabit Wireless Communication Challenges

    NASA Technical Reports Server (NTRS)

    Hwu, Shian U.

    2012-01-01

    This presentation briefly discusses a research effort on Terabit Wireless communication systems for possible space applications. Recently, terahertz (THz) technology (300-3000 GHz frequency) has attracted a great deal of interest from academia and industry. This is due to a number of interesting features of THz waves, including the nearly unlimited bandwidths available, and the non-ionizing radiation nature which does not damage human tissues and DNA with minimum health threat. Also, as millimeter-wave communication systems mature, the focus of research is, naturally, moving to the THz range. Many scientists regard THz as the last great frontier of the electromagnetic spectrum, but finding new applications outside the traditional niches of radio astronomy, Earth and planetary remote sensing, and molecular spectroscopy particularly in biomedical imaging and wireless communications has been relatively slow. Radiologists find this area of study so attractive because t-rays are non-ionizing, which suggests no harm is done to tissue or DNA. They also offer the possibility of performing spectroscopic measurements over a very wide frequency range, and can even capture signatures from liquids and solids. According to Shannon theory, the broad bandwidth of the THz frequency bands can be used for terabit-per-second (Tb/s) wireless communication systems. This enables several new applications, such as cell phones with 360 degrees autostereoscopic displays, optic-fiber replacement, and wireless Tb/s file transferring. Although THz technology could satisfy the demand for an extremely high data rate, a number of technical challenges need to be overcome before its development. This presentation provides an overview the state-of-the- art in THz wireless communication and the technical challenges for an emerging application in Terabit wireless systems. The main issue for THz wave propagation is the high atmospheric attenuation, which is dominated by water vapor absorption in the THz

  4. 47 CFR 25.277 - Temporary fixed earth station operations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... proposed temporary fixed earth station site before beginning transmissions: (1) The name of the person... 47 Telecommunication 2 2012-10-01 2012-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations...

  5. 47 CFR 25.277 - Temporary fixed earth station operations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... proposed temporary fixed earth station site before beginning transmissions: (1) The name of the person... 47 Telecommunication 2 2014-10-01 2014-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations...

  6. 47 CFR 25.277 - Temporary fixed earth station operations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... proposed temporary fixed earth station site before beginning transmissions: (1) The name of the person... 47 Telecommunication 2 2013-10-01 2013-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations...

  7. 47 CFR 25.277 - Temporary fixed earth station operations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... proposed temporary fixed earth station site before beginning transmissions: (1) The name of the person... 47 Telecommunication 2 2011-10-01 2011-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations...

  8. 47 CFR 22.737 - Temporary fixed stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Temporary fixed stations. 22.737 Section 22.737... Radiotelephone Service Conventional Rural Radiotelephone Stations § 22.737 Temporary fixed stations. The FCC may, upon proper application therefor, authorize the construction and operation of temporary fixed stations...

  9. 47 CFR 22.737 - Temporary fixed stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Temporary fixed stations. 22.737 Section 22.737... Radiotelephone Service Conventional Rural Radiotelephone Stations § 22.737 Temporary fixed stations. The FCC may, upon proper application therefor, authorize the construction and operation of temporary fixed stations...

  10. 47 CFR 22.737 - Temporary fixed stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Temporary fixed stations. 22.737 Section 22.737... Radiotelephone Service Conventional Rural Radiotelephone Stations § 22.737 Temporary fixed stations. The FCC may, upon proper application therefor, authorize the construction and operation of temporary fixed stations...

  11. 47 CFR 90.245 - Fixed relay stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Fixed relay stations. 90.245 Section 90.245... MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.245 Fixed relay stations. Except where specifically provided for, fixed relay stations shall be authorized to operate only on...

  12. 47 CFR 90.245 - Fixed relay stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Fixed relay stations. 90.245 Section 90.245... MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.245 Fixed relay stations. Except where specifically provided for, fixed relay stations shall be authorized to operate only on...

  13. 47 CFR 90.245 - Fixed relay stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Fixed relay stations. 90.245 Section 90.245... MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.245 Fixed relay stations. Except where specifically provided for, fixed relay stations shall be authorized to operate only on...

  14. 47 CFR 90.245 - Fixed relay stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Fixed relay stations. 90.245 Section 90.245... MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.245 Fixed relay stations. Except where specifically provided for, fixed relay stations shall be authorized to operate only on...

  15. 47 CFR 90.245 - Fixed relay stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Fixed relay stations. 90.245 Section 90.245... MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.245 Fixed relay stations. Except where specifically provided for, fixed relay stations shall be authorized to operate only on...

  16. Wireless sensor platform

    DOEpatents

    Joshi, Pooran C.; Killough, Stephen M.; Kuruganti, Phani Teja

    2017-08-08

    A wireless sensor platform and methods of manufacture are provided. The platform involves providing a plurality of wireless sensors, where each of the sensors is fabricated on flexible substrates using printing techniques and low temperature curing. Each of the sensors can include planar sensor elements and planar antennas defined using the printing and curing. Further, each of the sensors can include a communications system configured to encode the data from the sensors into a spread spectrum code sequence that is transmitted to a central computer(s) for use in monitoring an area associated with the sensors.

  17. Wireless Testbed Bonsai

    DTIC Science & Technology

    2006-02-01

    wireless sensor device network, and a about 200 Stargate nodes higher-tier multi-hop peer- to-peer 802.11b wireless network. Leading up to the full ExScal...deployment, we conducted spatial scaling tests on our higher-tier protocols on a 7 × 7 grid of Stargates nodes 45m and with 90m separations respectively...onW and its scaled version W̃ . III. EXPERIMENTAL SETUP Description of Kansei testbed. A stargate is a single board linux-based computer [7]. It uses a

  18. Experience of wireless local area network in a radiation oncology department.

    PubMed

    Mandal, Abhijit; Asthana, Anupam Kumar; Aggarwal, Lalit Mohan

    2010-01-01

    The aim of this work is to develop a wireless local area network (LAN) between different types of users (Radiation Oncologists, Radiological Physicists, Radiation Technologists, etc) for efficient patient data management and to made easy the availability of information (chair side) to improve the quality of patient care in Radiation Oncology department. We have used mobile workstations (Laptops) and stationary workstations, all equipped with wireless-fidelity (Wi-Fi) access. Wireless standard 802.11g (as recommended by Institute of Electrical and Electronic Engineers (IEEE, Piscataway, NJ) has been used. The wireless networking was configured with the Service Set Identifier (SSID), Media Access Control (MAC) address filtering, and Wired Equivalent Privacy (WEP) network securities. We are successfully using this wireless network in sharing the indigenously developed patient information management software. The proper selection of the hardware and the software combined with a secure wireless LAN setup will lead to a more efficient and productive radiation oncology department.

  19. Real-time network traffic classification technique for wireless local area networks based on compressed sensing

    NASA Astrophysics Data System (ADS)

    Balouchestani, Mohammadreza

    2017-05-01

    Network traffic or data traffic in a Wireless Local Area Network (WLAN) is the amount of network packets moving across a wireless network from each wireless node to another wireless node, which provide the load of sampling in a wireless network. WLAN's Network traffic is the main component for network traffic measurement, network traffic control and simulation. Traffic classification technique is an essential tool for improving the Quality of Service (QoS) in different wireless networks in the complex applications such as local area networks, wireless local area networks, wireless personal area networks, wireless metropolitan area networks, and wide area networks. Network traffic classification is also an essential component in the products for QoS control in different wireless network systems and applications. Classifying network traffic in a WLAN allows to see what kinds of traffic we have in each part of the network, organize the various kinds of network traffic in each path into different classes in each path, and generate network traffic matrix in order to Identify and organize network traffic which is an important key for improving the QoS feature. To achieve effective network traffic classification, Real-time Network Traffic Classification (RNTC) algorithm for WLANs based on Compressed Sensing (CS) is presented in this paper. The fundamental goal of this algorithm is to solve difficult wireless network management problems. The proposed architecture allows reducing False Detection Rate (FDR) to 25% and Packet Delay (PD) to 15 %. The proposed architecture is also increased 10 % accuracy of wireless transmission, which provides a good background for establishing high quality wireless local area networks.

  20. Wireless Sensors Network (Sensornet)

    NASA Technical Reports Server (NTRS)

    Perotti, J.

    2003-01-01

    The Wireless Sensor Network System presented in this paper provides a flexible reconfigurable architecture that could be used in a broad range of applications. It also provides a sensor network with increased reliability; decreased maintainability costs, and assured data availability by autonomously and automatically reconfiguring to overcome communication interferences.

  1. Building the Wireless Campus

    ERIC Educational Resources Information Center

    Gerraughty, James F.; Shanafelt, Michael E.

    2005-01-01

    This prototype is a continuation of a series of wireless prototypes which began in August 2001 and was reported on again in August 2002. This is the final year of this prototype. This continuation allowed Saint Francis University's Center of Excellence for Remote and Medically Under-Served Areas (CERMUSA) to refine the existing WLAN for the Saint…

  2. Investigating Wireless Power Transfer

    ERIC Educational Resources Information Center

    St. John, Stuart A.

    Understanding Physics is a great end in itself, but is also crucial to keep pace with developments in modern technology. Wireless power transfer, known to many only as a means to charge electric toothbrushes, will soon be commonplace in charging phones, electric cars and implanted medical devices. This article outlines how to produce and use a…

  3. Wireless ferroelectric resonating sensor.

    PubMed

    Viikari, Ville; Seppa, Heikki; Mattila, Tomi; Alastalo, Ari

    2010-04-01

    This paper presents a passive wireless resonating sensor that is based on a ferroelectric varactor. The sensor replies with its data at an intermodulation frequency when a reader device illuminates it at 2 closely located frequencies. The paper derives a theoretical equation for the response of such a sensor, verifies the theory by simulations, and demonstrates a temperature sensor based on a ferroelectric varactor.

  4. High-speed digital wireless battlefield network

    NASA Astrophysics Data System (ADS)

    Dao, Son K.; Zhang, Yongguang; Shek, Eddie C.; van Buer, Darrel

    1999-07-01

    In the past two years, the Digital Wireless Battlefield Network consortium that consists of HRL Laboratories, Hughes Network Systems, Raytheon, and Stanford University has participated in the DARPA TRP program to leverage the efforts in the development of commercial digital wireless products for use in the 21st century battlefield. The consortium has developed an infrastructure and application testbed to support the digitized battlefield. The consortium has implemented and demonstrated this network system. Each member is currently utilizing many of the technology developed in this program in commercial products and offerings. These new communication hardware/software and the demonstrated networking features will benefit military systems and will be applicable to the commercial communication marketplace for high speed voice/data multimedia distribution services.

  5. LON Technology in Wireless Sensor Networking Applications

    PubMed Central

    Miskowicz, Marek; Golanski, Ryszard

    2006-01-01

    In the paper a discussion on how to optimize LonWorks/EIA-709 sensor networking technology for wireless applications, in presented. Main solutions offered by Local Operating Networks (LON, LonWorks) platform attractive for wireless communication, that is, the send-on-delta concept and the sleep mode, are displayed. The predictive p-persistent CSMA MAC protocol constituting the heart of the communication capability of LON networks is analysed in detail. Next, the message services are described, and the analytical evaluation of delivery reliability is derived. Performance evaluation based on simulation results for unicast traffic is presented first. In order to highlight the robustness of the predictive CSMA to overload situations, the saturation performance for a general case load scenario including multicast transactions is reported. The methods of effective management of energy consumption in LonWorks networks are discussed. Finally, the LON design tradeoffs are summarized.

  6. Cognitive Wireless Communications - A paradigm shift in dealing with radio resources as a prerequisite for the wireless network of the future - An overview on the topic of cognitive wireless technologies

    NASA Astrophysics Data System (ADS)

    Haustein, Thomas; Stanczak, Slawomir; Wolisz, Adam; Jondral, Friedrich; Schotten, Hans; Kraemer, Rolf; Mück, Markus; Mennenga, Horst; Bender, Paul

    2016-07-01

    Wireless radio communications systems form the basis for mobile network connections in the digital society. A limited amount of radio spectrum and a spatially densified use of wireless communications systems require a resource-efficient use of the spectrum. Mechanisms of cognitive radio may hold the key to a more efficient use of the available spectrum under consideration of quality of service requirements. These mechanisms take advantage of location-specific knowledge of the wireless channel occupation in the dimensions of frequency, time, location and direction in space and therefore enable co-existent and reliable wireless communication. The authors give an introduction to the status of cognitive wireless communication technology, which represents the starting point of a series of research projects promoted by BMBF during 2012-2014.

  7. 47 CFR 27.1217 - Competitive bidding procedures for the Broadband Radio Service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Broadband Radio Service. 27.1217 Section 27.1217 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Broadband Radio Service and Educational Broadband Service § 27.1217 Competitive bidding procedures for the Broadband Radio...

  8. 47 CFR 27.1217 - Competitive bidding procedures for the Broadband Radio Service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Broadband Radio Service. 27.1217 Section 27.1217 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Broadband Radio Service and Educational Broadband Service § 27.1217 Competitive bidding procedures for the Broadband Radio...

  9. 47 CFR 27.1217 - Competitive bidding procedures for the Broadband Radio Service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Broadband Radio Service. 27.1217 Section 27.1217 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Broadband Radio Service and Educational Broadband Service § 27.1217 Competitive bidding procedures for the Broadband Radio...

  10. 47 CFR 27.1217 - Competitive bidding procedures for the Broadband Radio Service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Broadband Radio Service. 27.1217 Section 27.1217 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Broadband Radio Service and Educational Broadband Service § 27.1217 Competitive bidding procedures for the Broadband Radio...

  11. 47 CFR 27.1217 - Competitive bidding procedures for the Broadband Radio Service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Broadband Radio Service. 27.1217 Section 27.1217 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Broadband Radio Service and Educational Broadband Service § 27.1217 Competitive bidding procedures for the Broadband Radio...

  12. NASA Bluetooth Wireless Communications

    NASA Technical Reports Server (NTRS)

    Miller, Robert D.

    2007-01-01

    NASA has been interested in wireless communications for many years, especially when the crew size of the International Space Station (ISS) was reduced to two members. NASA began a study to find ways to improve crew efficiency to make sure the ISS could be maintained with limited crew capacity and still be a valuable research testbed in Low-Earth Orbit (LEO). Currently the ISS audio system requires astronauts to be tethered to the audio system, specifically a device called the Audio Terminal Unit (ATU). Wireless communications would remove the tether and allow astronauts to freely float from experiment to experiment without having to worry about moving and reconnecting the associated cabling or finding the space equivalent of an extension cord. A wireless communication system would also improve safety and reduce system susceptibility to Electromagnetic Interference (EMI). Safety would be improved because a crewmember could quickly escape a fire while maintaining communications with the ground and other crewmembers at any location. In addition, it would allow the crew to overcome the volume limitations of the ISS ATU. This is especially important to the Portable Breathing Apparatus (PBA). The next generation of space vehicles and habitats also demand wireless attention. Orion will carry up to six crewmembers in a relatively small cabin. Yet, wireless could become a driving factor to reduce launch weight and increase habitable volume. Six crewmembers, each tethered to a panel, could result in a wiring mess even in nominal operations. In addition to Orion, research is being conducted to determine if Bluetooth is appropriate for Lunar Habitat applications.

  13. Fast, Effective Transmitter Placement in Wireless Mesh Networks

    DTIC Science & Technology

    2012-01-01

    INTRODUCTION Description of Problem A wireless mesh network (WMN) is a communications network of fixed access points (APs) that exchange electronic mes- sages...the name DIviding RECTangles). Un- like Lipschitzian optimization, DIRECT does not require a priori specification of the Lipschitz con- stant, nor...algorithm is that the optimality gap at any iteration is not known. Given the Lipschitz constant, we can calculate a lower bound, but in our

  14. 47 CFR 22.737 - Temporary fixed stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., upon proper application therefor, authorize the construction and operation of temporary fixed stations... 47 Telecommunication 2 2010-10-01 2010-10-01 false Temporary fixed stations. 22.737 Section 22.737 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES...

  15. 47 CFR 22.737 - Temporary fixed stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., upon proper application therefor, authorize the construction and operation of temporary fixed stations... 47 Telecommunication 2 2011-10-01 2011-10-01 false Temporary fixed stations. 22.737 Section 22.737 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES...

  16. 47 CFR 25.277 - Temporary fixed earth station operations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ....277 Section 25.277 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations. (a) When an earth station in the Fixed-Satellite Service is to remain at a single location for fewer...

  17. 78 FR 18527 - Implementation of Competitive Bidding for Commercial Broadcast and Instructional Television Fixed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-27

    ... Television Fixed Service Licenses AGENCY: Federal Communications Commission. ACTION: Final rule; correction... Bidding for Commercial Broadcast and Instructional Television Fixed Service Licenses, published in the... Instructional Television Fixed Service Licenses, MM Docket No. 97- 234 et al., First Report and Order, 13 FCC...

  18. Competition in the domain of wireless networks security

    NASA Astrophysics Data System (ADS)

    Bednarczyk, Mariusz

    2017-04-01

    Wireless networks are very popular and have found wide spread usage amongst various segments, also in military environment. The deployment of wireless infrastructures allow to reduce the time it takes to install and dismantle communications networks. With wireless, users are more mobile and can easily get access to the network resources all the time. However, wireless technologies like WiFi or Bluetooth have security issues that hackers have extensively exploited over the years. In the paper several serious security flaws in wireless technologies are presented. Most of them enable to get access to the internal networks and easily carry out man-in-the-middle attacks. Very often, they are used to launch massive denial of service attacks that target the physical infrastructure as well as the RF spectrum. For instance, there are well known instances of Bluetooth connection spoofing in order to steal WiFi password stored in the mobile device. To raise the security awareness and protect wireless networks against an adversary attack, an analysis of attack methods and tools over time is presented in the article. The particular attention is paid to the severity, possible targets as well as the ability to persist in the context of protective measures. Results show that an adversary can take complete control of the victims' mobile device features if the users forget to use simple safety principles.

  19. Wireless Sensors and Networks for Advanced Energy Management

    SciTech Connect

    Hardy, J.E.

    2005-05-06

    Numerous national studies and working groups have identified low-cost, very low-power wireless sensors and networks as a critical enabling technology for increasing energy efficiency, reducing waste, and optimizing processes. Research areas for developing such sensor and network platforms include microsensor arrays, ultra-low power electronics and signal conditioning, data/control transceivers, and robust wireless networks. A review of some of the research in the following areas will be discussed: (1) Low-cost, flexible multi-sensor array platforms (CO{sub 2}, NO{sub x}, CO, humidity, NH{sub 3}, O{sub 2}, occupancy, etc.) that enable energy and emission reductions in applications such as buildings and manufacturing; (2) Modeling investments (energy usage and savings to drive capital investment decisions) and estimated uptime improvements through pervasive gathering of equipment and process health data and its effects on energy; (3) Robust, self-configuring wireless sensor networks for energy management; and (4) Quality-of-service for secure and reliable data transmission from widely distributed sensors. Wireless communications is poised to support technical innovations in the industrial community, with widespread use of wireless sensors forecasted to improve manufacturing production and energy efficiency and reduce emissions. Progress being made in wireless system components, as described in this paper, is helping bring these projected improvements to reality.

  20. Mobility management techniques for the next-generation wireless networks

    NASA Astrophysics Data System (ADS)

    Sun, Junzhao; Howie, Douglas P.; Sauvola, Jaakko J.

    2001-10-01

    The tremendous demands from social market are pushing the booming development of mobile communications faster than ever before, leading to plenty of new advanced techniques emerging. With the converging of mobile and wireless communications with Internet services, the boundary between mobile personal telecommunications and wireless computer networks is disappearing. Wireless networks of the next generation need the support of all the advances on new architectures, standards, and protocols. Mobility management is an important issue in the area of mobile communications, which can be best solved at the network layer. One of the key features of the next generation wireless networks is all-IP infrastructure. This paper discusses the mobility management schemes for the next generation mobile networks through extending IP's functions with mobility support. A global hierarchical framework model for the mobility management of wireless networks is presented, in which the mobility management is divided into two complementary tasks: macro mobility and micro mobility. As the macro mobility solution, a basic principle of Mobile IP is introduced, together with the optimal schemes and the advances in IPv6. The disadvantages of the Mobile IP on solving the micro mobility problem are analyzed, on the basis of which three main proposals are discussed as the micro mobility solutions for mobile communications, including Hierarchical Mobile IP (HMIP), Cellular IP, and Handoff-Aware Wireless Access Internet Infrastructure (HAWAII). A unified model is also described in which the different micro mobility solutions can coexist simultaneously in mobile networks.

  1. 75 FR 54421 - Sixth Meeting: RTCA Special Committee 223: Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-07

    ... Overview of terrestrial communication networks (FAA) User Services and Applications (FAA) NASA Cleveland... Communications AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 223: Airport Surface Wireless Communications meeting. SUMMARY: The FAA...

  2. A Sensible Approach to Wireless Networking.

    ERIC Educational Resources Information Center

    Ahmed, S. Faruq

    2002-01-01

    Discusses radio frequency (R.F.) wireless technology, including industry standards, range (coverage) and throughput (data rate), wireless compared to wired networks, and considerations before embarking on a large-scale wireless project. (EV)

  3. A Sensible Approach to Wireless Networking.

    ERIC Educational Resources Information Center

    Ahmed, S. Faruq

    2002-01-01

    Discusses radio frequency (R.F.) wireless technology, including industry standards, range (coverage) and throughput (data rate), wireless compared to wired networks, and considerations before embarking on a large-scale wireless project. (EV)

  4. Advanced Wireless Integrated Navy Network

    DTIC Science & Technology

    2005-03-01

    Basing visualization of wireless technologies, Ad Hoc networks , network protocols, real-time resource allocation, Ultra Wideband (UWB) communications...4.1 TIP #1: Distributed MIMO UWB sensor networks incorporating software radio 67 4.2 TIP #2: Close-in UWB wireless with applications to Sea- Basing 68...4.3 TIP #3: Secure Ad Hoc Networks 73 4.4 TIP #4: Integration of Close-in UWB wireless with ESM crane for Sea Basing applications 75 5. FINANCIAL REPORT

  5. Wireless Seismometer for Venus

    NASA Technical Reports Server (NTRS)

    Ponchak, George E.; Scardelletti, Maximilian C.; Taylor, Brandt; Beard, Steve; Clougherty, Brian; Meredith, Roger D.; Beheim, Glenn M.; Kiefer, Walter S.; Hunter, Gary W.

    2014-01-01

    Measuring the seismic activity of Venus is critical to understanding its composition and interior dynamics. Because Venus has an average surface temperature of 462 C and the challenge of providing cooling to multiple seismometers, a high temperature, wireless sensor using a wide bandgap semiconductor is an attractive option. This paper presents progress towards a seismometer sensor with wireless capabilities for Venus applications. A variation in inductance of a coil caused by a 1 cm movement of a ferrite probe held in the coil and attached to a balanced leaf-spring seismometer causes a variation of 80 MHz in the transmitted signal from the oscillator sensor system at 420 C, which correlates to a 10 kHz mm sensitivity when the ferrite probe is located at the optimum location in the coil.

  6. 75 FR 32692 - Schools and Libraries Universal Service Support Mechanism

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-09

    .../anti-spam software, scheduling services, wireless Internet access applications, and web hosting. We... priced firewall services, anti-virus/anti-spam software, scheduling services, wireless Internet access..., Internet access, and internal connections. Section 254 of the Communications Act of 1934, as amended...

  7. Resource Management in QoS-Aware Wireless Cellular Networks

    ERIC Educational Resources Information Center

    Zhang, Zhi

    2011-01-01

    Emerging broadband wireless networks that support high speed packet data with heterogeneous quality of service (QoS) requirements demand more flexible and efficient use of the scarce spectral resource. Opportunistic scheduling exploits the time-varying, location-dependent channel conditions to achieve multiuser diversity. In this work, we study…

  8. Resource Management in QoS-Aware Wireless Cellular Networks

    ERIC Educational Resources Information Center

    Zhang, Zhi

    2011-01-01

    Emerging broadband wireless networks that support high speed packet data with heterogeneous quality of service (QoS) requirements demand more flexible and efficient use of the scarce spectral resource. Opportunistic scheduling exploits the time-varying, location-dependent channel conditions to achieve multiuser diversity. In this work, we study…

  9. Wearable wireless photoplethysmography sensors

    NASA Astrophysics Data System (ADS)

    Spigulis, Janis; Erts, Renars; Nikiforovs, Vladimirs; Kviesis-Kipge, Edgars

    2008-04-01

    Wearable health monitoring sensors may support early detection of abnormal conditions and prevention of their consequences. Recent designs of three wireless photoplethysmography monitoring devices embedded in hat, glove and sock, and connected to PC or mobile phone by means of the Bluetooth technology, are described. First results of distant monitoring of heart rate and pulse wave transit time using the newly developed devices are presented.

  10. Adapting Future Wireless Technologies

    DTIC Science & Technology

    2002-01-01

    technologies & integrating them into the GIG, and treating Army wireless systems in a merged context of "Network Operations" comprising converged voice and...Objective Force C4ISR must be able to support: • The evolution from circuit-switched to packet-switched communications. • Highly mobile, ad-hoc... convergence of radio functions with information management systems will provide the enabling technology to build network-centric operations capability into

  11. Wireless Computing Architecture

    DTIC Science & Technology

    2009-07-01

    mechanisms are relevant to a broad spectrum of applications , but are particularly important to data broadcast in wireless distributed computing...significantly improve applications where reliable data broadcast is required. For example, unmanned aerial vehicles (UAVs) may use Rainbow to distribute ...68-74. 8. Dean, J., Ghemawat, S., “ MapReduce : simplified data processing on large clusters ”, Communications of the ACM, 51, 1, 2008, pp. 107-113

  12. Learning sensor models for wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Ertin, Emre

    2007-04-01

    Sensor data generation is a key component of high fidelity design and testing of applications at scale. In addition to its utility in validation of applications and network services, it provides a theoretical basis for the design of algorithms for efficient sampling, compression and exfiltration of the sensor readings. Modeling of the environmental processes that gives rise to sensor readings is the core problem in physical sciences. Sensor modeling for wireless sensor networks combine the physics of signal generation and propagation with models of transducer saturation and fault models for hardware. In this paper we introduce a novel modeling technique for constructing probabilistic models for censored sensor readings. The model is an extension of the Gaussian process regression and applies to continuous valued readings subject to censoring. We illustrate the performance of the proposed technique in modeling wireless propagation between nodes of a wireless sensor network. The model can capture the non-isotropic nature of the propagation characteristics and utilizes the information from the packet reception failures. We use measured data set from the Kansei sensor network testbed using 802.15.4 radios.

  13. 47 CFR 101.69 - Transition of the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands from the fixed microwave...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., and 2160-2200 MHz bands from the fixed microwave services to personal communications services and...) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses License Transfers... MHz bands from the fixed microwave services to personal communications services and emerging...

  14. 47 CFR 101.69 - Transition of the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands from the fixed microwave...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., and 2160-2200 MHz bands from the fixed microwave services to personal communications services and...) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses License Transfers... MHz bands from the fixed microwave services to personal communications services and emerging...

  15. From early wireless to Everest.

    PubMed

    Allen, A

    1998-01-01

    Medical information has been transmitted using wireless technologies for almost 80 years. A "wired wireless" electronic stethoscope was developed by the U.S. Army Signal Corps in the early 1920's, for potential use in ship-to-shore transmission of cardiac sounds. [Winters SR. Diagnosis by wireless. Scientific American June 11, 1921, p. 465] Today, wireless is used in a wide range of medical applications and at sites from transoceanic air flights to offshore oil platforms to Mt. Everest. 'Wireless LANs' are often used in medical environments. Typically, nurses and physicians in a hospital or clinic use hand-held "wireless thin client" pen computers that exchange patient information and images with the hospital server. Numerous companies, such as Fujitsu (article below) and Cruise Technologies (www.cruisetech.com) manufacture handheld pen-entry computers. One company, LXE, integrates radio-frequency (RF) enhanced hand-held computers specifically designed for production use within a wireless LAN (www.lxe.com). Other companies (Proxim, Symbol, and others) supply the wireless RF LAN infrastructure for the enterprise. Unfortunately, there have been problems with widespread deployment of wireless LANs. Perhaps the biggest impediment has been the lack of standards. Although an international standard (IEEE 802.11) was adopted in 1997, most wireless LAN products still are not compatible with the equipment of competing companies. A problem with the current standard for LAN adapters is that throughput is limited to 3 Mbps--compared to at least 10 Mbps, and often 100 Mbps, in a hard-wired Ethernet LAN. An II Mbps standard is due out in the next year or so, but it will be at least 2 years before standards-compliant products are available. This story profiles some of the ways that wireless is being used to overcome gaps in terrestrial and within-enterprise communication.

  16. Unmanned Aerial Vehicle (UAV) Dynamic-Tracking Directional Wireless Antennas for Low Powered Applications that Require Reliable Extended Range Operations in Time Critical Scenarios

    SciTech Connect

    Scott G. Bauer; Matthew O. Anderson; James R. Hanneman

    2005-10-01

    The proven value of DOD Unmanned Aerial Vehicles (UAVs) will ultimately transition to National and Homeland Security missions that require real-time aerial surveillance, situation awareness, force protection, and sensor placement. Public services first responders who routinely risk personal safety to assess and report a situation for emergency actions will likely be the first to benefit from these new unmanned technologies. ‘Packable’ or ‘Portable’ small class UAVs will be particularly useful to the first responder. They require the least amount of training, no fixed infrastructure, and are capable of being launched and recovered from the point of emergency. All UAVs require wireless communication technologies for real- time applications. Typically on a small UAV, a low bandwidth telemetry link is required for command and control (C2), and systems health monitoring. If the UAV is equipped with a real-time Electro-Optical or Infrared (EO/Ir) video camera payload, a dedicated high bandwidth analog/digital link is usually required for reliable high-resolution imagery. In most cases, both the wireless telemetry and real-time video links will be integrated into the UAV with unity gain omni-directional antennas. With limited on-board power and payload capacity, a small UAV will be limited with the amount of radio-frequency (RF) energy it transmits to the users. Therefore, ‘packable’ and ‘portable’ UAVs will have limited useful operational ranges for first responders. This paper will discuss the limitations of small UAV wireless communications. The discussion will present an approach of utilizing a dynamic ground based real-time tracking high gain directional antenna to provide extend range stand-off operation, potential RF channel reuse, and assured telemetry and data communications from low-powered UAV deployed wireless assets.

  17. Hybrid positioning with lighting LEDs and Zigbee multihop wireless network

    NASA Astrophysics Data System (ADS)

    Lee, Y. U.; Baang, S.; Park, J.; Zhou, Z.; Kavehrad, M.

    2012-01-01

    A simple, accurate, secure, long-lasting, and portable hybrid positioning system is proposed and designed in this paper. It consists of a lighting LED that generates visible light data corresponding to position information of a target and a Zigbee wireless network communication module with low power, security, and service area expansion characteristics. Under an indoor environment where there is 23.62m distance between an observer and the target, the presented hybrid positioning system is tested and is verified with the functions of Zigbee three hop wireless networking and visible light communication (VLC) scheme. The test results are analyzed and discussed.

  18. NEURON: Enabling Autonomicity in Wireless Sensor Networks

    PubMed Central

    Zafeiropoulos, Anastasios; Gouvas, Panagiotis; Liakopoulos, Athanassios; Mentzas, Gregoris; Mitrou, Nikolas

    2010-01-01

    Future Wireless Sensor Networks (WSNs) will be ubiquitous, large-scale networks interconnected with the existing IP infrastructure. Autonomic functionalities have to be designed in order to reduce the complexity of their operation and management, and support the dissemination of knowledge within a WSN. In this paper a novel protocol for energy efficient deployment, clustering and routing in WSNs is proposed that focuses on the incorporation of autonomic functionalities in the existing approaches. The design of the protocol facilitates the design of innovative applications and services that are based on overlay topologies created through cooperation among the sensor nodes. PMID:22399931

  19. Fiber Optic Infrastructure for Wireless Communication Networks

    NASA Astrophysics Data System (ADS)

    Lau, Kam Y.; Cutrer, David M.; Georges, John B.; Yeung, Simon

    It is clear that to meet the new demands of wireless customers, conventional cellular service providers and upcoming Personal Communication Service (PCS) providers for conventional phone service and high bandwidth wireless LAN must upgrade their networks to provide complete radio coverage. This evolution has motivated the need for low-cost systems that transport radio signals to and from areas of poor signal coverage. The most important area where this problem must be solved is inside of buildings, since this is where people spend most of their time. Unfortunately, the in-building environment is also the most challenging area to provide radio coverage due to severe attenuation and multi-path effects. The problem must be tackled from the viewpoint of optimization of performance/cost ratio of the network. In this paper, we describe a system-level approach to tackle this problem. We demonstrate how one can trade-off hardware performance, which represent cost, with proper choice of system architecture which includes, among other factors, in-building radio environment, to arrive at an optimum network solution technically and economically.

  20. The Yurok Tribe's ``wireless'' electric utility

    SciTech Connect

    Starrs, T.J.; Jacobson, A.

    1999-07-01

    The Yurok Tribe is designing and implementing a rural electrification project to provide reliable electricity to a remote part of the Yurok Indian Reservation. The project relies primarily on grid-independent alternative energy systems using photovoltaic (PV) or small-scale hydroelectric power. As part of the project, the Tribe is providing routine maintenance and repair services, including the replacement of components as they wear out. In order to finance the maintenance and repair program, the Tribe is implementing a billing system that rewards customers for living within the renewable energy budgets of their alternative energy systems. In effect, the Tribe is developing a wireless utility to provide grid-independent electricity service that is metered and billed in a manner similar to conventional grid-connected service.

  1. Launching a Wireless Laptop Program

    ERIC Educational Resources Information Center

    Grignano, Domenic

    2007-01-01

    In this article, the author, as a technology director for East Rock Magnet School in New Haven, Connecticut, a federal government test site for laptop learning, shares his secrets to a successful implementation of a wireless laptop program: (1) Build a wireless foundation; (2) Do not choose the cheapest model just because of budget; (3) A sturdy…

  2. Unpowered wireless ultrasound tomography system

    NASA Astrophysics Data System (ADS)

    Zahedi, Farshad; Huang, Haiying

    2016-04-01

    In this paper, an unpowered wireless ultrasound tomography system is presented. The system consists of two subsystems; the wireless interrogation unit (WIU) and three wireless nodes installed on the structure. Each node is designed to work in generation and sensing modes, but operates at a specific microwave frequency. Wireless transmission of the ultrasound signals between the WIU and the wireless nodes is achieved by converting ultrasound signals to microwave signals and vice versa, using a microwave carrier signal. In the generation mode, both a carrier signal and an ultrasound modulated microwave signal are transmitted to the sensor nodes. Only the node whose operating frequency matches the carrier signal will receive these signals and demodulate them to recover the original ultrasound signal. In the sensing mode, a microwave carrier signal with two different frequency components matching the operating frequencies of the sensor nodes is broadcasted by the WIU. The sensor nodes, in turn, receive the corresponding carrier signals, modulate it with the ultrasound sensing signal, and wirelessly transmit the modulated signal back to the WIU. The demodulation of the sensing signals is performed in the WIU using a digital signal processing. Implementing a software receiver significantly reduces the complexity and the cost of the WIU. A wireless ultrasound tomography system is realized by interchanging the carrier frequencies so that the wireless transducers can take turn to serve as the actuator and sensors.

  3. Launching a Wireless Laptop Program

    ERIC Educational Resources Information Center

    Grignano, Domenic

    2007-01-01

    In this article, the author, as a technology director for East Rock Magnet School in New Haven, Connecticut, a federal government test site for laptop learning, shares his secrets to a successful implementation of a wireless laptop program: (1) Build a wireless foundation; (2) Do not choose the cheapest model just because of budget; (3) A sturdy…

  4. Some Challenges in Wireless Security

    DTIC Science & Technology

    2007-02-01

    Approved for public release, distribution unlimited This paper is part of the following report: TITLE: Proceedings of the ARO Planning Workshop on Embedded...inference, antenna sensitivity, wormholes " Computation capability " Characteristics of the wireless topology itself Summary * Most popular wireless

  5. "If the Water Is Nasty, Fix It."

    ERIC Educational Resources Information Center

    Boston, Bruce O.

    1999-01-01

    After taking an environmental inventory of their community, seventh-graders in a Denver-area middle school decided to tackle the drinking water problem and fix it. The school is one of seven participating in Earth Force, an environmental and community-service-learning program based in Alexandria, Virginia. The program's progress and six-step…

  6. Demonstration of UAV deployment and control of mobile wireless sensing networks for modal analysis of structures

    NASA Astrophysics Data System (ADS)

    Zhou, Hao; Hirose, Mitsuhito; Greenwood, William; Xiao, Yong; Lynch, Jerome; Zekkos, Dimitrios; Kamat, Vineet

    2016-04-01

    Unmanned aerial vehicles (UAVs) can serve as a powerful mobile sensing platform for assessing the health of civil infrastructure systems. To date, the majority of their uses have been dedicated to vision and laser-based spatial imaging using on-board cameras and LiDAR units, respectively. Comparatively less work has focused on integration of other sensing modalities relevant to structural monitoring applications. The overarching goal of this study is to explore the ability for UAVs to deploy a network of wireless sensors on structures for controlled vibration testing. The study develops a UAV platform with an integrated robotic gripper that can be used to install wireless sensors in structures, drop a heavy weight for the introduction of impact loads, and to uninstall wireless sensors for reinstallation elsewhere. A pose estimation algorithm is embedded in the UAV to estimate the location of the UAV during sensor placement and impact load introduction. The Martlet wireless sensor network architecture is integrated with the UAV to provide the UAV a mobile sensing capability. The UAV is programmed to command field deployed Martlets, aggregate and temporarily store data from the wireless sensor network, and to communicate data to a fixed base station on site. This study demonstrates the integrated UAV system using a simply supported beam in the lab with Martlet wireless sensors placed by the UAV and impact load testing performed. The study verifies the feasibility of the integrated UAV-wireless monitoring system architecture with accurate modal characteristics of the beam estimated by modal analysis.

  7. 75 FR 8400 - In the Matter of Certain Wireless Communications System Server Software, Wireless Handheld...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-24

    ... COMMISSION In the Matter of Certain Wireless Communications System Server Software, Wireless Handheld Devices... server software, wireless handheld devices and battery packs by reason of infringement of certain claims... importation of certain wireless communications system server software, wireless handheld devices or...

  8. Wireless Measurement of Rotation and Displacement Rate

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E.; Taylor, Bryant D.

    2007-01-01

    A magnetic field response sensor is designed to measure displacement or rotation rate without a physical connection to a power source, microprocessor, data acquisition equipment, or electrical circuitry. The sensor works with the magnetic field response recorder, which was described in Magnetic-Field-Response Measurement-Acquisition System, NASA Tech Briefs, Vol. 30, No. 6 (June 2006), page 28. These sensors are wirelessly powered and interrogated, and the measurement acquisition system and sensors are extremely lightweight.The response recorder uses oscillating magnetic fields to power the sensors. Once powered, the sensors respond with their own magnetic field. For displacement/ rotation measurements, the response recorder uses the sensor s response amplitude, which is dependent on the distance from the antenna. The recorder s antenna orientation and position are kept fixed, and the sampling period is constant.

  9. Performance Evolution of IEEE 802.11b Wireless Local Area Network

    NASA Astrophysics Data System (ADS)

    Malik, Deepak; Singhal, Ankur

    2011-12-01

    The Wireless network can be employed to connect wired network to the wireless network. Wireless local area networks (WLAN) are more bandwidth limited as compared to the wired networks because they rely on an inexpensive, but error prone, physical medium (air). Hence it is important to evaluate their performance. This paper presents a study of IEEE 802.11b wireless LAN (WLAN). The performance evaluation has been presented via a series of test with different parameters such as data rate, different number of nodes and physical characteristics. The different qualities of service parameter are chosen to be throughput, media access delay and dropped data packets. The simulation results show that an IEEE 802.11b WLAN can support up to 60 clients with modest throughput. Finally the results are compared to evaluate the performance of wireless local networks.

  10. 78 FR 43262 - Use of Wireless Mobile Data Devices as Transponders for the Commercial Motor Vehicle Information...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-19

    ... Federal Motor Carrier Safety Administration Use of Wireless Mobile Data Devices as Transponders for the...: FMCSA announces that Commercial Mobile Radio Services (CMRS) network devices can be used as transponders...) navigational units, and onboard telematics devices (referred to collectively as ``wireless mobile data...

  11. Views of wireless network systems.

    SciTech Connect

    Young, William Frederick; Duggan, David Patrick

    2003-10-01

    Wireless networking is becoming a common element of industrial, corporate, and home networks. Commercial wireless network systems have become reliable, while the cost of these solutions has become more affordable than equivalent wired network solutions. The security risks of wireless systems are higher than wired and have not been studied in depth. This report starts to bring together information on wireless architectures and their connection to wired networks. We detail information contained on the many different views of a wireless network system. The method of using multiple views of a system to assist in the determination of vulnerabilities comes from the Information Design Assurance Red Team (IDART{trademark}) Methodology of system analysis developed at Sandia National Laboratories.

  12. Application of neural networks to the dynamic spatial distribution of nodes within an urban wireless network

    NASA Astrophysics Data System (ADS)

    Hortos, William S.

    1995-04-01

    The optimal location of wireless transceivers or communicating sensor devices in an urban area and within large human-made structures is considered. The purpose of the positioning of the devices is formation of a distributed network, either in a mesh or hub-spoke topology, that achieves robust connectivity of the nodes. Real-world examples include wireless local area networks (LANs) within buildings and radio beacons in an outdoor mobile radio environment. Operating environments contain both fixed and moving interferers that correspond to both stationary and time-varying spatial distributions of path distortion of stationary and transient fading and multipath delays that impede connectivity. The positioning of the autonomous wireless devices in an area with an unknown spatial pattern of interferers would normally be a slow incremental process. The proposed objective is determination of the spatial distribution of the devices to achieve the maximum radio connectivity in a minimal number of iterative steps. Impeding the optimal distribution of wireless nodes is the corresponding distribution of environmental interferers in the area or volume of network operation. The problem of network formation is posed as an adaptive learning problem, in particular, a self-organizing map of locally competitive wireless units that recursively update their positions and individual operating configurations at each iterative step of the neural algorithm. The scheme allows the wireless units to adaptively learn the pattern distribution of interferers in their operating environment based on the level of radio interference measured at each node by an equivalent received signal strength from wireless units within the node's hearing distance. Two cases are considered. The first is an indoor human-made environment where the interference pattern is largely deterministic and stationary and the units are positioned to form a wireless LAN. The second situation applies to an outdoor urban

  13. Bidirectional fiber-wireless and fiber-VLLC transmission system based on an OEO-based BLS and a RSOA.

    PubMed

    Lu, Hai-Han; Li, Chung-Yi; Lu, Ting-Chien; Wu, Chang-Jen; Chu, Chien-An; Shiva, Ajay; Mochii, Takao

    2016-02-01

    A bidirectional fiber-wireless and fiber-visible-laser-light-communication (VLLC) transmission system based on an optoelectronic oscillator (OEO)-based broadband light source (BLS) and a reflective semiconductor optical amplifier (RSOA) is proposed and experimentally demonstrated. Through an in-depth observation of such bidirectional fiber-wireless and fiber-VLLC transmission systems, good bit error rate performances are obtained over a 40 km single-mode fiber and a 10 m RF/optical wireless transport. Such a bidirectional fiber-wireless and fiber-VLLC transmission system is an attractive option for providing broadband integrated services.

  14. Semantic Visualization of Wireless Sensor Networks for Elderly Monitoring

    NASA Astrophysics Data System (ADS)

    Stocklöw, Carsten; Kamieth, Felix

    In the area of Ambient Intelligence, Wireless Sensor Networks are commonly used for user monitoring purposes like health monitoring and user localization. Existing work on visualization of wireless sensor networks focuses mainly on displaying individual nodes and logical, graph-based topologies. This way, the relation to the real-world deployment is lost. This paper presents a novel approach for visualization of wireless sensor networks and interaction with complex services on the nodes. The environment is realized as a 3D model, and multiple nodes, that are worn by a single individual, are grouped together to allow an intuitive interface for end users. We describe application examples and show that our approach allows easier access to network information and functionality by comparing it with existing solutions.

  15. Wireless Technology in K-12 Education

    ERIC Educational Resources Information Center

    Walery, Darrell

    2004-01-01

    Many schools begin implementing wireless technology slowly by creating wireless "hotspots" on the fly. This is accomplished by putting a wireless access point on a cart along with a set of wireless laptop computers. A teacher can then wheel the cart anywhere in the school that has a network drop, plug the access point in and have an…

  16. Wireless Technology in K-12 Education

    ERIC Educational Resources Information Center

    Walery, Darrell

    2004-01-01

    Many schools begin implementing wireless technology slowly by creating wireless "hotspots" on the fly. This is accomplished by putting a wireless access point on a cart along with a set of wireless laptop computers. A teacher can then wheel the cart anywhere in the school that has a network drop, plug the access point in and have an…

  17. Wireless technologies for closed-loop retinal prostheses.

    PubMed

    Ng, David C; Bai, Shun; Yang, Jiawei; Tran, Nhan; Skafidas, Efstratios

    2009-12-01

    In this paper, we discuss various technologies needed to develop retinal prostheses with wireless power and data telemetry operation. In addition to the need to communicate with the implanted device, supply of power to the retinal prosthesis is especially difficult. This is because, in the implanted state, the device is not fixed in position due to constant motion of the eye. Furthermore, a retinal prosthesis incorporating a high density electrode array of more than 1000 electrodes is expected to consume approximately 45 mW of power and require 300 kbps of image and stimulation data. The front end of the wireless power and data transmission, the antenna, needs to be small compared to the size of the eye. Also, the wireless module is expected to operate in the reactive near-field region due to small separation between the transmit and receive antennas compared to their size and corresponding operating wavelength. An inductive link is studied as a means to transfer power and for data telemetry between the implant and external unit. In this work, the use of integrated circuit and microfabrication technologies for implementing inductive links is discussed. A closed-loop approach is taken to improve performance and reach optimum operation condition. Design and simulation data are presented as the basis for development of viable wireless module prototypes.

  18. Real-time and secure wireless health monitoring.

    PubMed

    Dağtaş, S; Pekhteryev, G; Sahinoğlu, Z; Cam, H; Challa, N

    2008-01-01

    We present a framework for a wireless health monitoring system using wireless networks such as ZigBee. Vital signals are collected and processed using a 3-tiered architecture. The first stage is the mobile device carried on the body that runs a number of wired and wireless probes. This device is also designed to perform some basic processing such as the heart rate and fatal failure detection. At the second stage, further processing is performed by a local server using the raw data transmitted by the mobile device continuously. The raw data is also stored at this server. The processed data as well as the analysis results are then transmitted to the service provider center for diagnostic reviews as well as storage. The main advantages of the proposed framework are (1) the ability to detect signals wirelessly within a body sensor network (BSN), (2) low-power and reliable data transmission through ZigBee network nodes, (3) secure transmission of medical data over BSN, (4) efficient channel allocation for medical data transmission over wireless networks, and (5) optimized analysis of data using an adaptive architecture that maximizes the utility of processing and computational capacity at each platform.

  19. Deployable wireless Fresnel lens

    NASA Technical Reports Server (NTRS)

    Kennedy, Timothy F. (Inventor); Fink, Patrick W. (Inventor); Chu, Andrew W. (Inventor); Lin, Gregory Y. (Inventor)

    2013-01-01

    Apparatus and methods for enhancing the gain of a wireless signal are provided. In at least one specific embodiment, the apparatus can include a screen comprised of one or more electrically conductive regions for reflecting electromagnetic radiation and one or more non-conductive regions for permitting electromagnetic radiation therethrough. The one or more electrically conductive regions can be disposed adjacent to at least one of the one or more non-conductive regions. The apparatus can also include a support member disposed about at least a portion of the screen. The screen can be capable of collapsing by twisting the support member in opposite screw senses to form interleaved concentric sections.

  20. Investigating wireless power transfer

    NASA Astrophysics Data System (ADS)

    St John, Stuart A.

    2017-09-01

    Understanding Physics is a great end in itself, but is also crucial to keep pace with developments in modern technology. Wireless power transfer, known to many only as a means to charge electric toothbrushes, will soon be commonplace in charging phones, electric cars and implanted medical devices. This article outlines how to produce and use a simple set of equipment to both demonstrate and investigate this phenomenon. It presents some initial findings and aims to encourage Physics educators and their students to conduct further research, pushing the bounds of their understanding.

  1. Wireless Chemical Sensing Method

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E. (Inventor); Oglesby, Donald M. (Inventor); Taylor, Bryant D. (Inventor)

    2017-01-01

    A wireless chemical sensor includes an electrical conductor and a material separated therefrom by an electric insulator. The electrical conductor is an unconnected open-circuit shaped for storage of an electric field and a magnetic field. In the presence of a time-varying magnetic field, the first electrical conductor resonates to generate harmonic electric and magnetic field responses. The material is positioned at a location lying within at least one of the electric and magnetic field responses so-generated. The material changes in electrical conductivity in the presence of a chemical-of-interest.

  2. Wireless passive radiation sensor

    DOEpatents

    Pfeifer, Kent B; Rumpf, Arthur N; Yelton, William G; Limmer, Steven J

    2013-12-03

    A novel measurement technique is employed using surface acoustic wave (SAW) devices, passive RF, and radiation-sensitive films to provide a wireless passive radiation sensor that requires no batteries, outside wiring, or regular maintenance. The sensor is small (<1 cm.sup.2), physically robust, and will operate unattended for decades. In addition, the sensor can be insensitive to measurement position and read distance due to a novel self-referencing technique eliminating the need to measure absolute responses that are dependent on RF transmitter location and power.

  3. Wireless Telemetry and Command (T and C) Program

    NASA Technical Reports Server (NTRS)

    Jiang, Hui; Horan, Stephen

    2000-01-01

    The Wireless Telemetry and Command (T&C) program is to investigate methods of using commercial telecommunications service providers to support command and telemetry services between a remote user and a base station. While the initial development is based on ground networks, the development is being done with an eye towards future space communications needs. Both NASA and the Air Force have indicated a plan to consider the use of commercial telecommunications providers to support their space missions. To do this, there will need to be an understanding of the requirements and limitations of interfacing with the commercial providers. The eventual payoff will be the reduced operations cost and the ability to tap into commercial services being developed by the commercial networks. This should enable easier realization of EP services to the end points, commercial routing of data, and quicker integration of new services into the space mission operations. Therefore, the ultimate goal of this program is not just to provide wireless radio communications for T&C services but to enhance those services through wireless networking and provider enhancements that come with the networks. In the following chapters, the detailed technical procedure will be showed step by step. Chapter 2 will talk about the general idea of simulation as well as the implementation of data acquisition including sensor array data and GPS data. Chapter 3 will talk about how to use LabVEEW and Component Works to do wireless communication simulation and how to distribute the real-time information over the Internet by using Visual Basic and ActiveX controls. Also talk about the test configuration and validation. Chapter 4 will show the test results both from In-Lab test and Networking Test. Chapter 5 will summarize the whole procedure and give the perspective for the future consideration.

  4. 48 CFR 49.504 - Termination of fixed-price contracts for default.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Termination of fixed-price... fixed-price contracts for default. (a)(1) Supplies and services. The contracting officer shall insert the clause at 52.249-8, Default (Fixed-Price Supply and Service), in solicitations and contracts when...

  5. Hand Gesture Based Wireless Robotic Arm Control for Agricultural Applications

    NASA Astrophysics Data System (ADS)

    Kannan Megalingam, Rajesh; Bandhyopadhyay, Shiva; Vamsy Vivek, Gedela; Juned Rahi, Muhammad

    2017-08-01

    One of the major challenges in agriculture is harvesting. It is very hard and sometimes even unsafe for workers to go to each plant and pluck fruits. Robotic systems are increasingly combined with new technologies to automate or semi automate labour intensive work, such as e.g. grape harvesting. In this work we propose a semi-automatic method for aid in harvesting fruits and hence increase productivity per man hour. A robotic arm fixed to a rover roams in the in orchard and the user can control it remotely using the hand glove fixed with various sensors. These sensors can position the robotic arm remotely to harvest the fruits. In this paper we discuss the design of hand glove fixed with various sensors, design of 4 DoF robotic arm and the wireless control interface. In addition the setup of the system and the testing and evaluation under lab conditions are also presented in this paper.

  6. Cross-layer optimization of video streaming in single-hop wireless networks

    NASA Astrophysics Data System (ADS)

    Hsu, Cheng-Hsin; Hefeeda, Mohamed

    2009-01-01

    Video streaming over wireless networks is getting very popular because of the high bandwidth and the support of quality of service offered by recent wireless standards, such as IEEE 802.11e. We consider optimizing the quality of video streaming in single-hop wireless networks that are composed of multiple wireless stations. Our optimization problem controls parameters in different layers to optimally allocate the wireless network resources among all stations. We address this problem in two steps. First, we formulate an abstract optimization problem for video streaming in single-hop wireless networks in general. This formulation exposes the important interaction between parameters belonging to different layers in the network stack. Then, we instantiate and solve the general problem for the recent IEEE 802.11e WLANs, which support prioritized traffic classes. We show how the calculated optimal solutions can efficiently be implemented in the distributed mode of the IEEE 802.11e standard. We evaluate our proposed solution using extensive simulations in the OPNET simulator, which captures most features of realistic wireless networks. In addition, to show the practicability of our solution, we have implemented it in the driver of an off-the-shelf wireless adapter that complies with the IEEE 802.11e standard. Our experimental and simulation results show that significant quality improvement in video streams can be achieved using our solution, without incurring any significant communication or computational overhead.

  7. Future Fixed Target Facilities

    SciTech Connect

    Melnitchouk, Wolodymyr

    2009-01-01

    We review plans for future fixed target lepton- and hadron-scattering facilities, including the 12 GeV upgraded CEBAF accelerator at Jefferson Lab, neutrino beam facilities at Fermilab, and the antiproton PANDA facility at FAIR. We also briefly review recent theoretical developments which will aid in the interpretation of the data expected from these facilities.

  8. Fixing Dataset Search

    NASA Technical Reports Server (NTRS)

    Lynnes, Chris

    2014-01-01

    Three current search engines are queried for ozone data at the GES DISC. The results range from sub-optimal to counter-intuitive. We propose a method to fix dataset search by implementing a robust relevancy ranking scheme. The relevancy ranking scheme is based on several heuristics culled from more than 20 years of helping users select datasets.

  9. Fixed mount wavefront sensor

    DOEpatents

    Neal, Daniel R.

    2000-01-01

    A rigid mount and method of mounting for a wavefront sensor. A wavefront dissector, such as a lenslet array, is rigidly mounted at a fixed distance relative to an imager, such as a CCD camera, without need for a relay imaging lens therebetween.

  10. Three-Phase Scheme for Supporting Time-Constrained Data with Duplication in Wireless Broadcast Systems

    NASA Astrophysics Data System (ADS)

    Chen, Chao-Chun; Lin, Lien-Fa; Wang, Shih-Chia

    The wireless data broadcast techniques raised in 1990s. Since the wireless data dissemination techniques are emerged, more and more data services are proposed based on the wireless data broadcast techniques in these years. Among the new services, the time-constraint data broadcast service is critical for many real-time related applications, and has been studied in the recent years. However, the related works did not consider the duplicate pages of requests on data scheduling. Hence, in this paper, we consider the duplicate pages in the multi-page time-constraint data broadcast service. We first proposed a duplication page-optimized architecture for supporting the multi-page time-constraint data broadcast service. We then proposed a three-phase scheme for the time-slot sharing optimizer to improve the bandwidth utility of the TDA-based program. The experiments reveal that our proposed indeed significantly reduce the number of used channels for a data broadcast server.

  11. Smart programmable wireless microaccelerometers

    NASA Astrophysics Data System (ADS)

    Varadan, Vijay K.; Subramanian, Hareesh; Varadan, Vasundara V.

    1998-07-01

    The integration of MEMS, SAW devices and required microelectronics and conformal antenna to realize a programmable wireless accelerometer is presented in this paper. This unique combination of technologies results in a novel accelerometer that can be remotely sensed by a microwave system with the advantage of no power requirements at the sensor site. The microaccelerometer presented is simple in construction and easy to manufacture with existing silicon micromachining techniques. Programmable accelerometers can be achieved with splitfinger interdigital transducers (IDTs) as reflecting structures. If IDTs are short circuited or capacitively loaded, the wave propagates without any reflection whereas in an open circuit configuration, the IDTs reflect the incoming SAW signal. The programmable accelerometers can thus be achieved by using an external circuitry on a semiconductor chip using hybrid technology. The relatively small size of the sensor makes it an ideal conformal sensor. The accelerometer finds application as air bag deployment sensors, vibration sensors for noise control, deflection and strain sensors, inertial and dimensional positioning systems, ABS/traction control, smart suspension, active roll stabilization and four wheel steering. The wireless accelerometer is very attractive to study the response of a `dummy' in automobile crash test.

  12. [Remote wireless monitoring].

    PubMed

    Villar-Montini, Alex

    2009-12-01

    The increasing device implantations to treat cardiovascular diseases such as arrhytmias and heart failures, aging of the population, and the growing number of patients with access to new therapies as well as the wider access to health systems are the reasons why the number of new implantations carried out each year is rising. Hence, we should have an equipment that can control these patients at a distance, making the follow-up closer. The answer to this enormous challenge is the remote monitoring of these devices. Biotronik is a pioneer in this task and since 2001 it has been comercializing pacemakers and portable wireless monitors (CardioMessenger). Currently, there are more than 100,000 installed systems. Thanks to the continuous and completely automatized follow-up, as well as the wireless net, the system integrity can be confirmed, and then proceed to adjust the therapies in an optimized manner according to each patient's needs; also take action to prevent the development of some arrhytmias, or even the evolution of a heart failure. Likewise, the system can improve the clynical efficiency of the treatment and help to economize to the Ministry of Healthcare.

  13. Biomonitoring with Wireless Communications

    SciTech Connect

    Budinger, Thomas F.

    2003-03-01

    This review is divided into three sections: technologies for monitoring physiological parameters; biosensors for chemical assays and wireless communications technologies including image transmissions. Applications range from monitoring high risk patients for heart, respiratory activity and falls to sensing levels of physical activity in military, rescue, and sports personnel. The range of measurements include, heart rate, pulse wave form, respiratory rate, blood oxygen, tissue pCO2, exhaled carbon dioxide and physical activity. Other feasible measurements will employ miniature chemical laboratories on silicon or plastic chips. The measurements can be extended to clinical chemical assays ranging from common blood assays to protein or specialized protein measurements (e.g., troponin, creatine, and cytokines such as TNF and IL6). Though the feasibility of using wireless technology to communicate vital signs has been demonstrated 32 years ago (1) it has been only recently that practical and portable devices and communications net works have become generally available for inexpensive deployment of comfortable and affordable devices and systems.

  14. An EMI-aware prioritized wireless access scheme for e-Health applications in hospital environments.

    PubMed

    Phunchongharn, Phond; Niyato, Dusit; Hossain, Ekram; Camorlinga, Sergio

    2010-09-01

    Wireless communications technologies can support efficient healthcare services in medical and patient-care environments. However, using wireless communications in a healthcare environment raises two crucial issues. First, the RF transmission can cause electromagnetic interference (EMI) to biomedical devices, which could critically malfunction. Second, the different types of electronic health (e-Health) applications require different quality of service (QoS). In this paper, we introduce an innovative wireless access scheme, called EMI-aware prioritized wireless access, to address these issues. First, the system architecture for the proposed scheme is introduced. Then, an EMI-aware handshaking protocol is proposed for e-Health applications in a hospital environment. This protocol provides safety to the biomedical devices from harmful interference by adapting transmit power of wireless devices based on the EMI constraints. A prioritized wireless access scheme is proposed for channel access by two different types of applications with different priorities. A Markov chain model is presented to study the queuing behavior of the proposed system. Then, this queuing model is used to optimize the performance of the system given the QoS requirements. Finally, the performance of the proposed wireless access scheme is evaluated through extensive simulations.

  15. Mobility- Aware Cache Management in Wireless Environment

    NASA Astrophysics Data System (ADS)

    Kaur, Gagandeep; Saini, J. S.

    2010-11-01

    In infrastructure wireless environments, a base station provides communication links between mobile client and remote servers. Placing a proxy cache at the base station is an effective way of managing the wireless Internet bandwidth efficiently. However, in the situation of non-uniform heavy traffic, requests of all the mobile clients in the service area of the base station may cause overload in the cache. If the proxy cache has to release some cache space for the new mobile client in the environment, overload occurs. In this paper, we propose a novel cache management strategy to decrease the penalty of overloaded traffic on the proxy and to reduce the number of remote accesses by increasing the cache hit ratio. We predict the number of overload ahead of time based on its history and adapt the cache for the heavy traffic to be able to provide continuous and fair service to the current mobile clients and incoming ones. We have tested the algorithms over a real implementation of the cache management system in presence of fault tolerance and security. In our cache replacement algorithm, mobility of the clients, predicted overload number, size of the cached packets and their access frequencies are considered altogether. Performance results show that our cache management strategy outperforms the existing policies with less number of overloads and higher cache hit ratio.

  16. Wireless Communications in Smart Grid

    NASA Astrophysics Data System (ADS)

    Bojkovic, Zoran; Bakmaz, Bojan

    Communication networks play a crucial role in smart grid, as the intelligence of this complex system is built based on information exchange across the power grid. Wireless communications and networking are among the most economical ways to build the essential part of the scalable communication infrastructure for smart grid. In particular, wireless networks will be deployed widely in the smart grid for automatic meter reading, remote system and customer site monitoring, as well as equipment fault diagnosing. With an increasing interest from both the academic and industrial communities, this chapter systematically investigates recent advances in wireless communication technology for the smart grid.

  17. Radio Relays Improve Wireless Products

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Signal Hill, California-based XCOM Wireless Inc. developed radio frequency micromachine (RF MEMS) relays with a Phase II Small Business Innovation Research (SBIR) contract through NASA?s Jet Propulsion Laboratory. In order to improve satellite communication systems, XCOM produced wireless RF MEMS relays and tunable capacitors that use metal-to-metal contact and have the potential to outperform most semiconductor technologies while using less power. These relays are used in high-frequency test equipment and instrumentation, where increased speed can mean significant cost savings. Applications now also include mainstream wireless applications and greatly improved tactical radios.

  18. Wireless device monitoring methods, wireless device monitoring systems, and articles of manufacture

    DOEpatents

    McCown, Steven H [Rigby, ID; Derr, Kurt W [Idaho Falls, ID; Rohde, Kenneth W [Idaho Falls, ID

    2012-05-08

    Wireless device monitoring methods, wireless device monitoring systems, and articles of manufacture are described. According to one embodiment, a wireless device monitoring method includes accessing device configuration information of a wireless device present at a secure area, wherein the device configuration information comprises information regarding a configuration of the wireless device, accessing stored information corresponding to the wireless device, wherein the stored information comprises information regarding the configuration of the wireless device, comparing the device configuration information with the stored information, and indicating the wireless device as one of authorized and unauthorized for presence at the secure area using the comparing.

  19. Wireless Overlay Backhauling over Bidirectional Colorless WDM-PONs: the Impact of the Baseband Channel

    NASA Astrophysics Data System (ADS)

    Avó, Ricardo; Medeiros, Maria C. R.

    2013-12-01

    Next generation wavelength division multiplexed passive optical access networks (WDM-PON), employing reflective semiconductor optical amplifiers (RSOAs), can provide a cost effective solution to jointly support both, classic PON services and transparent overlay wireless backhauling. In this approach, the wireless signals are transparently transmitted over the WDMPON, thus creating a virtual dedicated network without incurring into additional network installation and maintenance costs. In this paper, the performance of a WDM-PON transmitting an overlay orthogonal frequency-division multiplexing (OFDM) wireless signal is assessed analytically and experimentally, with relevant system impairments being identified and system design guidelines are provided.

  20. 48 CFR 546.302 - Fixed-price supply contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Fixed-price supply contracts. 546.302 Section 546.302 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 546.302 Fixed-price supply contracts. ...

  1. 48 CFR 546.302 - Fixed-price supply contracts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Fixed-price supply contracts. 546.302 Section 546.302 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 546.302 Fixed-price supply contracts. ...

  2. 48 CFR 546.302 - Fixed-price supply contracts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Fixed-price supply contracts. 546.302 Section 546.302 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 546.302 Fixed-price supply contracts. ...

  3. 48 CFR 546.302 - Fixed-price supply contracts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Fixed-price supply contracts. 546.302 Section 546.302 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 546.302 Fixed-price supply contracts. ...

  4. 48 CFR 546.302 - Fixed-price supply contracts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Fixed-price supply contracts. 546.302 Section 546.302 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 546.302 Fixed-price supply contracts. ...

  5. Development of a mini-mobile digital radiography system by using wireless smart devices.

    PubMed

    Jeong, Chang-Won; Joo, Su-Chong; Ryu, Jong-Hyun; Lee, Jinseok; Kim, Kyong-Woo; Yoon, Kwon-Ha

    2014-08-01

    The current technologies that trend in digital radiology (DR) are toward systems using portable smart mobile as patient-centered care. We aimed to develop a mini-mobile DR system by using smart devices for wireless connection into medical information systems. We developed a mini-mobile DR system consisting of an X-ray source and a Complementary Metal-Oxide Semiconductor (CMOS) sensor based on a flat panel detector for small-field diagnostics in patients. It is used instead of the systems that are difficult to perform with a fixed traditional device. We also designed a method for embedded systems in the development of portable DR systems. The external interface used the fast and stable IEEE 802.11n wireless protocol, and we adapted the device for connections with Picture Archiving and Communication System (PACS) and smart devices. The smart device could display images on an external monitor other than the monitor in the DR system. The communication modules, main control board, and external interface supporting smart devices were implemented. Further, a smart viewer based on the external interface was developed to display image files on various smart devices. In addition, the advantage of operators is to reduce radiation dose when using remote smart devices. It is integrated with smart devices that can provide X-ray imaging services anywhere. With this technology, it can permit image observation on a smart device from a remote location by connecting to the external interface. We evaluated the response time of the mini-mobile DR system to compare to mobile PACS. The experimental results show that our system outperforms conventional mobile PACS in this regard.

  6. Design and implementation of location-based wireless targeted advertising

    NASA Astrophysics Data System (ADS)

    Li, Benjamin; Xu, Deyin

    2001-10-01

    As advertisements are time and location sensitive, a challenge for wireless marketing is to have advertisements delivered when and where they are most convenient. In this paper we introduce a two-stage auction model for location-based wireless targeted advertising. This system extends the notion of location-based service by using location information to target advertising, and does so specifically by enabling advertisers to specify their preferences and bid for advertisement delivery, where those preferences are then used in a subsequent automated auction of actual deliveries to wireless data users. The automated auction in the second stage is especially effective because it can use information about the individual user profile data, including customer relationship management system contents as well as location from the wireless system's location management service, including potentially location history such as current trajectory from recent history and longer-term historical trip records for that user. Through two-stage auction, real-time bidding by advertisers and matching ads contents to mobile users help advertising information reach maximal value.

  7. Wireless video monitoring and robot control in security applications

    NASA Astrophysics Data System (ADS)

    Nurkkala, Eero A.; Pyssysalo, Tino; Roning, Juha

    1998-10-01

    This research focuses on applications based on wireless monitoring and robot control, utilizing motion image and augmented reality. These applications include remote services and surveillance-related functions such as remote monitoring. A remote service can be, for example, a way to deliver products at a hospital or old people's home. Due to the mobile nature of the system, monitoring at places with privacy concerns is possible. On the other hand, mobility demands wireless communications. Suitable and present technologies for wireless video transfer are weighted. Identification of objects with the help of Radio Frequency Identifying (RFID) technology and facial recognition results in intelligent actions, for example, where the control of a robot does not require extensive workload from the user. In other words, tasks can be partially autonomous, RFID can be also used in augmentation of the video view with virtual objects. As a real-life experiment, a prototype environment is being constructed that consists of a robot equipped with a video camera and wireless links to the network and multimedia computer.

  8. Ultrasonic wireless health monitoring

    NASA Astrophysics Data System (ADS)

    Petit, Lionel; Lefeuvre, Elie; Guyomar, Daniel; Richard, Claude; Guy, Philippe; Yuse, Kaori; Monnier, Thomas

    2006-03-01

    The integration of autonomous wireless elements in health monitoring network increases the reliability by suppressing power supplies and data transmission wiring. Micro-power piezoelectric generators are an attractive alternative to primary batteries which are limited by a finite amount of energy, a limited capacity retention and a short shelf life (few years). Our goal is to implement such an energy harvesting system for powering a single AWT (Autonomous Wireless Transmitter) using our SSH (Synchronized Switch Harvesting) method. Based on a non linear process of the piezoelement voltage, this SSH method optimizes the energy extraction from the mechanical vibrations. This AWT has two main functions : The generation of an identifier code by RF transmission to the central receiver and the Lamb wave generation for the health monitoring of the host structure. A damage index is derived from the variation between the transmitted wave spectrum and a reference spectrum. The same piezoelements are used for the energy harvesting function and the Lamb wave generation, thus reducing mass and cost. A micro-controller drives the energy balance and synchronizes the functions. Such an autonomous transmitter has been evaluated on a 300x50x2 mm 3 composite cantilever beam. Four 33x11x0.3 mm 3 piezoelements are used for the energy harvesting and for the wave lamb generation. A piezoelectric sensor is placed at the free end of the beam to track the transmitted Lamb wave. In this configuration, the needed energy for the RF emission is 0.1 mJ for a 1 byte-information and the Lamb wave emission requires less than 0.1mJ. The AWT can harvested an energy quantity of approximately 20 mJ (for a 1.5 Mpa lateral stress) with a 470 μF storage capacitor. This corresponds to a power density near to 6mW/cm 3. The experimental AWT energy abilities are presented and the damage detection process is discussed. Finally, some envisaged solutions are introduced for the implementation of the required data

  9. Fixed solar collection system

    SciTech Connect

    Tipton, H.R.

    1984-07-31

    A fixed solar energy collector system has facing panels of different size forming a Vee-shaped trough open at its base and supporting a plurality of highly reflective convex reflectors strategically disposed upon said panels in reflective relationship to a plurality of Fresnel lenses positioned at the base of the trough. A suitable reflector, disposed beneath the Fresnel lenses, directs the reflected energy to a heat-needy target.

  10. Fixed pitch wind turbines

    NASA Technical Reports Server (NTRS)

    Fenn, D. B.; Viterna, L. A.

    1978-01-01

    Wind turbines designed for fixed pitch operation offer potential reductions in the cost of the machine by eliminating many costly components. It was shown that a rotor can be designed which produces the same energy annually as Mod-0 but which regulates its power automatically by progressively stalling the blades as wind speed increases. Effects of blade twist, taper, root cutout, and airfoil shape on performance are discussed as well as various starting technqiues.

  11. Neutrophilic Fixed Drug Eruption.

    PubMed

    Waldman, Leah; Reddy, Swathi B; Kassim, Andrea; Dettloff, Jennifer; Reddy, Vijaya B

    2015-07-01

    Fixed drug eruption (FDE) is a cutaneous reaction to a medication that recurs in the same fairly localized site with each exposure to the offending drug. The classical histopathologic findings in FDE consist of an interface dermatitis with predominantly lymphocytic inflammatory cell infiltrate. An unusual case of FDE in a 27-year-old pregnant woman who presented with widespread lesions and a predominantly neutrophilic infiltrate on histopathologic examination is reported.

  12. Wireless Damage Location Sensing System

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E. (Inventor); Taylor, Bryant Douglas (Inventor)

    2012-01-01

    A wireless damage location sensing system uses a geometric-patterned wireless sensor that resonates in the presence of a time-varying magnetic field to generate a harmonic response that will experience a change when the sensor experiences a change in its geometric pattern. The sensing system also includes a magnetic field response recorder for wirelessly transmitting the time-varying magnetic field and for wirelessly detecting the harmonic response. The sensing system compares the actual harmonic response to a plurality of predetermined harmonic responses. Each predetermined harmonic response is associated with a severing of the sensor at a corresponding known location thereof so that a match between the actual harmonic response and one of the predetermined harmonic responses defines the known location of the severing that is associated therewith.

  13. Wireless Josephson amplifier

    SciTech Connect

    Narla, A.; Sliwa, K. M.; Hatridge, M.; Shankar, S.; Frunzio, L.; Schoelkopf, R. J.; Devoret, M. H.

    2014-06-09

    Josephson junction parametric amplifiers are playing a crucial role in the readout chain in superconducting quantum information experiments. However, their integration with current 3D cavity implementations poses the problem of transitioning between waveguide, coax cables, and planar circuits. Moreover, Josephson amplifiers require auxiliary microwave components, like directional couplers and/or hybrids, that are sources of spurious losses and impedance mismatches that limit measurement efficiency and amplifier tunability. We have developed a wireless architecture for these parametric amplifiers that eliminates superfluous microwave components and interconnects. This greatly simplifies their assembly and integration into experiments. We present an experimental realization of such a device operating in the 9–11 GHz band with about 100 MHz of amplitude gain-bandwidth product, on par with devices mounted in conventional sample holders. The simpler impedance environment presented to the amplifier also results in increased amplifier tunability.

  14. Towards biodegradable wireless implants.

    PubMed

    Boutry, Clémentine M; Chandrahalim, Hengky; Streit, Patrick; Schinhammer, Michael; Hänzi, Anja C; Hierold, Christofer

    2012-05-28

    A new generation of partially or even fully biodegradable implants is emerging. The idea of using temporary devices is to avoid a second surgery to remove the implant after its period of use, thereby improving considerably the patient's comfort and safety. This paper provides a state-of-the-art overview and an experimental section that describes the key technological challenges for making biodegradable devices. The general considerations for the design and synthesis of biodegradable components are illustrated with radiofrequency-driven resistor-inductor-capacitor (RLC) resonators made of biodegradable metals (Mg, Mg alloy, Fe, Fe alloys) and biodegradable conductive polymer composites (polycaprolactone-polypyrrole, polylactide-polypyrrole). Two concepts for partially/fully biodegradable wireless implants are discussed, the ultimate goal being to obtain a fully biodegradable sensor for in vivo sensing.

  15. Wireless Josephson amplifier

    NASA Astrophysics Data System (ADS)

    Narla, A.; Sliwa, K. M.; Hatridge, M.; Shankar, S.; Frunzio, L.; Schoelkopf, R. J.; Devoret, M. H.

    2014-06-01

    Josephson junction parametric amplifiers are playing a crucial role in the readout chain in superconducting quantum information experiments. However, their integration with current 3D cavity implementations poses the problem of transitioning between waveguide, coax cables, and planar circuits. Moreover, Josephson amplifiers require auxiliary microwave components, like directional couplers and/or hybrids, that are sources of spurious losses and impedance mismatches that limit measurement efficiency and amplifier tunability. We have developed a wireless architecture for these parametric amplifiers that eliminates superfluous microwave components and interconnects. This greatly simplifies their assembly and integration into experiments. We present an experimental realization of such a device operating in the 9-11 GHz band with about 100 MHz of amplitude gain-bandwidth product, on par with devices mounted in conventional sample holders. The simpler impedance environment presented to the amplifier also results in increased amplifier tunability.

  16. Wireless sensor network

    NASA Astrophysics Data System (ADS)

    Perotti, Jose M.; Lucena, Angel R.; Mullenix, Pamela A.; Mata, Carlos T.

    2006-05-01

    Current and future requirements of aerospace sensors and transducers demand the design and development of a new family of sensing devices, with emphasis on reduced weight, power consumption, and physical size. This new generation of sensors and transducers will possess a certain degree of intelligence in order to provide the end user with critical data in a more efficient manner. Communication between networks of traditional or next-generation sensors can be accomplished by a Wireless Sensor Network (WSN) developed by NASA's Instrumentation Branch and ASRC Aerospace Corporation at Kennedy Space Center (KSC), consisting of at least one central station and several remote stations and their associated software. The central station is application-dependent and can be implemented on different computer hardware, including industrial, handheld, or PC-104 single-board computers, on a variety of operating systems: embedded Windows, Linux, VxWorks, etc. The central stations and remote stations share a similar radio frequency (RF) core module hardware that is modular in design. The main components of the remote stations are an RF core module, a sensor interface module, batteries, and a power management module. These modules are stackable, and a common bus provides the flexibility to stack other modules for additional memory, increased processing, etc. WSN can automatically reconfigure to an alternate frequency if interference is encountered during operation. In addition, the base station will autonomously search for a remote station that was perceived to be lost, using relay stations and alternate frequencies. Several wireless remote-station types were developed and tested in the laboratory to support different sensing technologies, such as resistive temperature devices, silicon diodes, strain gauges, pressure transducers, and hydrogen leak detectors.

  17. Compressive sensing based wireless sensor for structural health monitoring

    NASA Astrophysics Data System (ADS)

    Bao, Yuequan; Zou, Zilong; Li, Hui

    2014-03-01

    Data loss is a common problem for monitoring systems based on wireless sensors. Reliable communication protocols, which enhance communication reliability by repetitively transmitting unreceived packets, is one approach to tackle the problem of data loss. An alternative approach allows data loss to some extent and seeks to recover the lost data from an algorithmic point of view. Compressive sensing (CS) provides such a data loss recovery technique. This technique can be embedded into smart wireless sensors and effectively increases wireless communication reliability without retransmitting the data. The basic idea of CS-based approach is that, instead of transmitting the raw signal acquired by the sensor, a transformed signal that is generated by projecting the raw signal onto a random matrix, is transmitted. Some data loss may occur during the transmission of this transformed signal. However, according to the theory of CS, the raw signal can be effectively reconstructed from the received incomplete transformed signal given that the raw signal is compressible in some basis and the data loss ratio is low. This CS-based technique is implemented into the Imote2 smart sensor platform using the foundation of Illinois Structural Health Monitoring Project (ISHMP) Service Tool-suite. To overcome the constraints of limited onboard resources of wireless sensor nodes, a method called random demodulator (RD) is employed to provide memory and power efficient construction of the random sampling matrix. Adaptation of RD sampling matrix is made to accommodate data loss in wireless transmission and meet the objectives of the data recovery. The embedded program is tested in a series of sensing and communication experiments. Examples and parametric study are presented to demonstrate the applicability of the embedded program as well as to show the efficacy of CS-based data loss recovery for real wireless SHM systems.

  18. Thermoelectric Powered Wireless Sensors for Dry-Cask Storage

    NASA Astrophysics Data System (ADS)

    Carstens, Thomas Alan

    This study focuses on the development of self-powered wireless sensors. These sensors can be used to measure key parameters in extreme environments; e.g., temperature monitoring for spent nuclear fuel during dry-cask storage. This study has developed a design methodology for these self-powered monitoring systems. The main elements that constitute this work consist of selecting and testing a power source for the wireless sensor, determination of the attenuation of the wireless signal, and testing the wireless sensor circuitry in an extreme environment. OrigenArp determined the decay heat and gamma/neutron source strength of the spent fuel throughout the service life of the dry-cask. A first principles analysis modeled the temperatures inside the dry-cask. A finite-element heat transfer code calculated the temperature distribution of the thermoelectric and heat sink. The temperature distributions determine the power produced by the thermoelectric. It was experimentally verified that a thermoelectric generator (HZ-14) with a DC/DC converter (Linear Technology LTC3108EDE) can power a transceiver (EmbedRF) at condition which represent prototypical conditions throughout and beyond the service life of the dry-cask. The wireless sensor is required to broadcast with enough power to overcome the attenuation from the dry-cask. It will be important to minimize the attenuation of the signal in order to broadcast with a small transmission power. To investigate the signal transmission through the dry-cask, CST Microwave Studio was used to determine the scattering parameter S2,1 for a horizontal dry-cask. Important parameters that can influence the transmission of the signal are antenna orientation, antenna placement, and transmission frequency. The thermoelectric generator, DC/DC converter, and transceiver were exposed to 60Co gamma radiation (exposure rate170.3 Rad/min) at the University of Wisconsin Medical Radiation Research Center. The effects of gamma radiation on the

  19. Wireless Instrumentation Use on Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Sherman, Aaron

    2010-01-01

    This slide presentation reviews the results of a study on the use of wireless instrumentation and sensors on future launch vehicles. The use of wireless technologies would if feasible would allow for fewer wires, and allow for more flexibility. However, it was generally concluded that wireless solutions are not currently ready to replace wired technologies for launch vehicles. The recommendations of the study were to continue to use wired sensors as the primary choice for vehicle instrumentation, and to continue to assess needs and use wireless instrumentation where appropriate. The future work includes support efforts for wireless technologies, and continue to monitor the development of wireless solutions.

  20. Wireless image streaming in mobile ultrasound.

    PubMed

    Dickson, Brett W; Pedersen, Peder C

    2010-03-01

    This work evaluates the feasibility of using 802.11 g ad hoc and 3G cellular broadband networks to wirelessly stream ultrasound video in real-time. Telemedicine ultrasound applications in events such as disaster relief and first-response triage can incorporate these technologies, enabling onsite medical personnel to receive assistance with diagnostic decisions by remote medical experts. The H.264 scalable video codec was used to encode echocardiographic video streams at various image resolutions (video graphics array [VGA] and quarter video graphics array [QVGA]) and frame rates (10, 15, 20, and 30 frames/s). The video stream was transmitted using 802.11 g and 3G cellular technologies, and pertinent transmission parameters such as data rate, packet loss, delay jitter, and latency were measured. 802.11 g permits high frame rate and VGA resolution and has low latency and jitter, but it is suitable only for short communication ranges, whereas the 3G cellular network allows medium to low frame rate streaming at QVGA image resolution with medium latency. However, video streaming can take place from any location with 3G service to any other site with Internet connectivity. The transmitted ultrasound video streams were subsequently recorded and evaluated by physicians with expertise in medical ultrasonography who evaluated the diagnostic value of the received video streams relative to the original videos. They expressed the opinion that image quality in the case of both 802.11 g and 3G was fully to adequately preserved, but missed frames could momentarily decrease the diagnostic value. This research demonstrates that 3G and 802.11 g wireless networks combined with efficient video compression make diagnostically valuable wireless streaming of ultrasound video feasible.

  1. Principles in wireless building health monitoring systems.

    NASA Astrophysics Data System (ADS)

    Pentaris, F. P.; Makris, J. P.; Stonham, J.; Vallianatos, F.

    2012-04-01

    Monitoring the structural state of a building is essential for the safety of the people who work, live, visit or just use it as well as for the civil protection of urban areas. Many factors can affect the state of the health of a structure, namely man made, like mistakes in the construction, traffic, heavy loads on the structures, explosions, environmental impacts like wind loads, humidity, chemical reactions, temperature changes and saltiness, and natural hazards like earthquakes and landslides. Monitoring the health of a structure provides the ability to anticipate structural failures and secure the safe use of buildings especially those of public services. This work reviews the state of the art and the challenges of a wireless Structural Health Monitoring (WiSHM). Literature review reveals that although there is significant evolution in wireless structural health monitoring, in many cases, monitoring by itself is not enough to predict when a structure becomes inappropriate and/or unsafe for use, and the damage or low durability of a structure cannot be revealed (Chintalapudi, et al., 2006; Ramos, Aguilar, & Lourenço, 2011). Several features and specifications of WiSHM like wireless sensor networking, reliability and autonomy of sensors, algorithms of data transmission and analysis should still be evolved and improved in order to increase the predictive effectiveness of the SHM (Jinping Ou & Hui Li, 2010; Lu & Loh, 2010) . Acknowledgments This work was supported in part by the ARCHEMEDES III Program of the Ministry of Education of Greece and the European Union in the framework of the project entitled «Interdisciplinary Multi-Scale Research of Earthquake Physics and Seismotectonics at the front of the Hellenic Arc (IMPACT-ARC) ».

  2. Fixed solar energy concentrator

    SciTech Connect

    Houghton, A.J.; Knasel, T.M.

    1981-01-20

    An apparatus for the concentration of solar energy upon a fixed array of solar cells is disclosed. A transparent material is overlayed upon the cell array, and a diffuse reflective coating is applied to the surface area of the transparent medium in between cells. Radiant light, which reflects through the transparent layer and does not fall directly incident to a cell surface is reflected by the coating layer in an approximate cosine pattern. Thereafter, such light undergoes internal reflection and rediffusion until subsequently it either strikes a solar cell surface or is lost through the upper surface of the transparent material.

  3. Real time network traffic monitoring for wireless local area networks based on compressed sensing

    NASA Astrophysics Data System (ADS)

    Balouchestani, Mohammadreza

    2017-05-01

    A wireless local area network (WLAN) is an important type of wireless networks which connotes different wireless nodes in a local area network. WLANs suffer from important problems such as network load balancing, large amount of energy, and load of sampling. This paper presents a new networking traffic approach based on Compressed Sensing (CS) for improving the quality of WLANs. The proposed architecture allows reducing Data Delay Probability (DDP) to 15%, which is a good record for WLANs. The proposed architecture is increased Data Throughput (DT) to 22 % and Signal to Noise (S/N) ratio to 17 %, which provide a good background for establishing high qualified local area networks. This architecture enables continuous data acquisition and compression of WLAN's signals that are suitable for a variety of other wireless networking applications. At the transmitter side of each wireless node, an analog-CS framework is applied at the sensing step before analog to digital converter in order to generate the compressed version of the input signal. At the receiver side of wireless node, a reconstruction algorithm is applied in order to reconstruct the original signals from the compressed signals with high probability and enough accuracy. The proposed algorithm out-performs existing algorithms by achieving a good level of Quality of Service (QoS). This ability allows reducing 15 % of Bit Error Rate (BER) at each wireless node.

  4. Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture

    DOEpatents

    Steele, Kerry D [Kennewick, WA; Anderson, Gordon A [Benton City, WA; Gilbert, Ronald W [Morgan Hill, CA

    2011-02-01

    Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture are described. In one aspect, a communications device identification method includes providing identification information regarding a group of wireless identification devices within a wireless communications range of a reader, using the provided identification information, selecting one of a plurality of different search procedures for identifying unidentified ones of the wireless identification devices within the wireless communications range, and identifying at least some of the unidentified ones of the wireless identification devices using the selected one of the search procedures.

  5. 47 CFR 64.3100 - Restrictions on mobile service commercial messages.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... device that is utilized by a subscriber of a commercial mobile service (as such term is defined in... receive mobile service commercial messages sent to his/her wireless device from a particular sender. The... specifically for wireless devices in connection with commercial mobile service in the manner and time-frame...

  6. Mobilize Your instruction Program with Wireless Technology.

    ERIC Educational Resources Information Center

    Mathias, Molly Susan; Heser, Steven

    2002-01-01

    Describes the use of wireless technology for library bibliographic instruction at the Milwaukee Area Technical College. Highlights include a wireless mobile cart that holds laptop computers; faculty support; future plans; and recommendations, including investigating technology infrastructure and marketing. (LRW)

  7. Fixed Sagittal Plane Imbalance

    PubMed Central

    Savage, Jason W.; Patel, Alpesh A.

    2014-01-01

    Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis < 5 cm, pelvic tilt < 20 degrees, and lumbar lordosis equal to pelvic incidence ± 9 degrees. Conclusion Sagittal plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction. PMID:25396111

  8. Fixed sagittal plane imbalance.

    PubMed

    Savage, Jason W; Patel, Alpesh A

    2014-12-01

    Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis < 5 cm, pelvic tilt < 20 degrees, and lumbar lordosis equal to pelvic incidence ± 9 degrees. Conclusion Sagittal plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction.

  9. Review: Security in Wireless Technologies in Business

    NASA Astrophysics Data System (ADS)

    Sattarova, F. Y.; Kim, Tai-Hoon

    Wireless technology seems to be everywhere now - but it is still relatively in its infancy. New standards and protocols continue to emerge and problems and bugs are discovered. Nevertheless, wireless networks make many things much more convenient and it appears that wireless networks are here to stay. The differences and similarities of wireless and wired security, the new threats brought by mobility, the security of networks and devices and effects of security, or lack of it are shortly discussed in this review paper.

  10. Emerging Trends in Healthcare Adoption of Wireless Body Area Networks.

    PubMed

    Rangarajan, Anuradha

    2016-01-01

    Real-time personal health monitoring is gaining new ground with advances in wireless communications. Wireless body area networks (WBANs) provide a means for low-powered sensors, affixed either on the human body or in vivo, to communicate with each other and with external telecommunication networks. The healthcare benefits of WBANs include continuous monitoring of patient vitals, measuring postacute rehabilitation time, and improving quality of medical care provided in medical emergencies. This study sought to examine emerging trends in WBAN adoption in healthcare. To that end, a systematic literature survey was undertaken against the PubMed database. The search criteria focused on peer-reviewed articles that contained the keywords "wireless body area network" and "healthcare" or "wireless body area network" and "health care." A comprehensive review of these articles was performed to identify adoption dimensions, including underlying technology framework, healthcare subdomain, and applicable lessons-learned. This article benefits healthcare technology professionals by identifying gaps in implementation of current technology and highlighting opportunities for improving products and services.

  11. Resource Optimization Scheme for Multimedia-Enabled Wireless Mesh Networks

    PubMed Central

    Ali, Amjad; Ahmed, Muhammad Ejaz; Piran, Md. Jalil; Suh, Doug Young

    2014-01-01

    Wireless mesh networking is a promising technology that can support numerous multimedia applications. Multimedia applications have stringent quality of service (QoS) requirements, i.e., bandwidth, delay, jitter, and packet loss ratio. Enabling such QoS-demanding applications over wireless mesh networks (WMNs) require QoS provisioning routing protocols that lead to the network resource underutilization problem. Moreover, random topology deployment leads to have some unused network resources. Therefore, resource optimization is one of the most critical design issues in multi-hop, multi-radio WMNs enabled with multimedia applications. Resource optimization has been studied extensively in the literature for wireless Ad Hoc and sensor networks, but existing studies have not considered resource underutilization issues caused by QoS provisioning routing and random topology deployment. Finding a QoS-provisioned path in wireless mesh networks is an NP complete problem. In this paper, we propose a novel Integer Linear Programming (ILP) optimization model to reconstruct the optimal connected mesh backbone topology with a minimum number of links and relay nodes which satisfies the given end-to-end QoS demands for multimedia traffic and identification of extra resources, while maintaining redundancy. We further propose a polynomial time heuristic algorithm called Link and Node Removal Considering Residual Capacity and Traffic Demands (LNR-RCTD). Simulation studies prove that our heuristic algorithm provides near-optimal results and saves about 20% of resources from being wasted by QoS provisioning routing and random topology deployment. PMID:25111241

  12. Resource optimization scheme for multimedia-enabled wireless mesh networks.

    PubMed

    Ali, Amjad; Ahmed, Muhammad Ejaz; Piran, Md Jalil; Suh, Doug Young

    2014-08-08

    Wireless mesh networking is a promising technology that can support numerous multimedia applications. Multimedia applications have stringent quality of service (QoS) requirements, i.e., bandwidth, delay, jitter, and packet loss ratio. Enabling such QoS-demanding applications over wireless mesh networks (WMNs) require QoS provisioning routing protocols that lead to the network resource underutilization problem. Moreover, random topology deployment leads to have some unused network resources. Therefore, resource optimization is one of the most critical design issues in multi-hop, multi-radio WMNs enabled with multimedia applications. Resource optimization has been studied extensively in the literature for wireless Ad Hoc and sensor networks, but existing studies have not considered resource underutilization issues caused by QoS provisioning routing and random topology deployment. Finding a QoS-provisioned path in wireless mesh networks is an NP complete problem. In this paper, we propose a novel Integer Linear Programming (ILP) optimization model to reconstruct the optimal connected mesh backbone topology with a minimum number of links and relay nodes which satisfies the given end-to-end QoS demands for multimedia traffic and identification of extra resources, while maintaining redundancy. We further propose a polynomial time heuristic algorithm called Link and Node Removal Considering Residual Capacity and Traffic Demands (LNR-RCTD). Simulation studies prove that our heuristic algorithm provides near-optimal results and saves about 20% of resources from being wasted by QoS provisioning routing and random topology deployment.

  13. Advanced Wireless Sensor Nodes - MSFC

    NASA Technical Reports Server (NTRS)

    Varnavas, Kosta; Richeson, Jeff

    2017-01-01

    NASA field center Marshall Space Flight Center (Huntsville, AL), has invested in advanced wireless sensor technology development. Developments for a wireless microcontroller back-end were primarily focused on the commercial Synapse Wireless family of devices. These devices have many useful features for NASA applications, good characteristics and the ability to be programmed Over-The-Air (OTA). The effort has focused on two widely used sensor types, mechanical strain gauges and thermal sensors. Mechanical strain gauges are used extensively in NASA structural testing and even on vehicle instrumentation systems. Additionally, thermal monitoring with many types of sensors is extensively used. These thermal sensors include thermocouples of all types, resistive temperature devices (RTDs), diodes and other thermal sensor types. The wireless thermal board will accommodate all of these types of sensor inputs to an analog front end. The analog front end on each of the sensors interfaces to the Synapse wireless microcontroller, based on the Atmel Atmega128 device. Once the analog sensor output data is digitized by the onboard analog to digital converter (A/D), the data is available for analysis, computation or transmission. Various hardware features allow custom embedded software to manage battery power to enhance battery life. This technology development fits nicely into using numerous additional sensor front ends, including some of the low-cost printed circuit board capacitive moisture content sensors currently being developed at Auburn University.

  14. Energy-Efficient Implementation of ECDH Key Exchange for Wireless Sensor Networks

    NASA Astrophysics Data System (ADS)

    Lederer, Christian; Mader, Roland; Koschuch, Manuel; Großschädl, Johann; Szekely, Alexander; Tillich, Stefan

    Wireless Sensor Networks (WSNs) are playing a vital role in an ever-growing number of applications ranging from environmental surveillance over medical monitoring to home automation. Since WSNs are often deployed in unattended or even hostile environments, they can be subject to various malicious attacks, including the manipulation and capture of nodes. The establishment of a shared secret key between two or more individual nodes is one of the most important security services needed to guarantee the proper functioning of a sensor network. Despite some recent advances in this field, the efficient implementation of cryptographic key establishment for WSNs remains a challenge due to the resource constraints of small sensor nodes such as the MICAz mote. In this paper we present a lightweight implementation of the elliptic curve Diffie-Hellman (ECDH) key exchange for ZigBee-compliant sensor nodes equipped with an ATmega128 processor running the TinyOS operating system. Our implementation uses a 192-bit prime field specified by the NIST as underlying algebraic structure and requires only 5.20 ·106 clock cycles to compute a scalar multiplication if the base point is fixed and known a priori. A scalar multiplication using a random base point takes about 12.33 ·106 cycles. Our results show that a full ECDH key exchange between two MICAz motes consumes an energy of 57.33 mJ (including radio communication), which is significantly better than most previously reported ECDH implementations on comparable platforms.

  15. 78 FR 20628 - Wireless Metering Challenge

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-05

    ... (EERE) requests comments on the draft version of the Wireless Power Meter Challenge Specification. This... development of new technologies in the wireless electric metering space. DATES: Comments on the Wireless Meter... INFORMATION section. ADDRESSES: Comments may be submitted by electronic mail to...

  16. Wireless Andrew: Everywhere You Want To Be.

    ERIC Educational Resources Information Center

    Futhey, Tracy

    2000-01-01

    Describes the wireless local area network at Carnegie Mellon University. Highlights include classroom applications, particularly in the Business School; the use of laptop computers configured with wireless technology; handheld computers, including use for testing; and assuring appropriate uses of wireless technology. (LRW)

  17. Adaptive Protocols for Mobile Wireless Networks

    DTIC Science & Technology

    2005-12-22

    frequency-hop wireless networks," International Journal of Wireless Information Networks , vol. 11, no. 3, pp. 147-159, July 2004. [PRW04c] M. B. Pursley...efficient routing of multimedia traffic in frequency-hop packet radio networks," submitted for publication in the International Journal of Wireless Information Networks , August

  18. A Wireless Communications Systems Laboratory Course

    ERIC Educational Resources Information Center

    Guzelgoz, Sabih; Arslan, Huseyin

    2010-01-01

    A novel wireless communications systems laboratory course is introduced. The course teaches students how to design, test, and simulate wireless systems using modern instrumentation and computer-aided design (CAD) software. One of the objectives of the course is to help students understand the theoretical concepts behind wireless communication…

  19. A Wireless Communications Systems Laboratory Course

    ERIC Educational Resources Information Center

    Guzelgoz, Sabih; Arslan, Huseyin

    2010-01-01

    A novel wireless communications systems laboratory course is introduced. The course teaches students how to design, test, and simulate wireless systems using modern instrumentation and computer-aided design (CAD) software. One of the objectives of the course is to help students understand the theoretical concepts behind wireless communication…

  20. Photonics for wireless communications

    NASA Astrophysics Data System (ADS)

    Paul, Dilip K.

    1995-09-01

    The problem of optimum signal transmission/reception is addressed under a wireless acoustics data communications framework. The ocean waveguide can be modeled as an inhomogeneous dispersive medium with a frequency- dependent Green's function. An FDM-type reception scheme with non- overlapping acoustic subchannels is proposed. This methodology exploits the optimal propagation frequencies along specific ducts and paths in the ocean waveguide. The parallel data transmission system used frequency division multiplexed (FDM) channels to avoid equalization techniques which introduce higher-order computational complexity to the receiver. Multicarrier modulation (MCM) ameliorates the effects of multipaths, and allows operation at multiples of the single-carrier transmission rate. The long symbol time used in multicarrier modulation increases the system margins against noise, intersymbol interference (ISI) and fast fades. Network topology issues are considered to determine optimum network architectures for underwater acoustic LAN's. A central network topology supported by a blind adaptive equalization (BAE) transmission technique is proposed as superior to a distributed topology in terms of power, bandwidth efficiency, setup simplicity, and elimination of overhead bits for short data packet exchange. Included is an investigation on the factors controlling the system's power efficiency.

  1. Wireless Remote Monitoring of Toxic Gases in Shipbuilding

    PubMed Central

    Pérez-Garrido, Carlos; González-Castaño, Francisco J.; Chaves-Diéguez, David; Rodríguez-Hernández, Pedro S.

    2014-01-01

    Large-scale wireless sensor networks have not achieved market impact, so far. Nevertheless, this technology may be applied successfully to small-scale niche markets. Shipyards are hazardous working environments with many potential risks to worker safety. Toxic gases generated in soldering processes in enclosed spaces (e.g., cargo holds) are one such risk. The dynamic environment of a ship under construction makes it very difficult to plan gas detection fixed infrastructures connected to external monitoring stations via wired links. While portable devices with gas level indicators exist, they require workers to monitor measurements, often in situations where they are focused on other tasks for relatively long periods. In this work, we present a wireless multihop remote gas monitoring system for shipyard environments that has been tested in a real ship under construction. Using this system, we validate IEEE 802.15.4/Zigbee wireless networks as a suitable technology to connect gas detectors to control stations outside the ships. These networks have the added benefit that they reconfigure themselves dynamically in case of network failure or redeployment, for example when a relay is moved to a new location. Performance measurements include round trip time (which determines the alert response time for safety teams) and link quality indicator and packet error rate (which determine communication robustness). PMID:24534919

  2. Seamless interworking architecture for WBAN in heterogeneous wireless networks with QoS guarantees.

    PubMed

    Khan, Pervez; Ullah, Niamat; Ullah, Sana; Kwak, Kyung Sup

    2011-10-01

    The IEEE 802.15.6 standard is a communication standard optimized for low-power and short-range in-body/on-body nodes to serve a variety of medical, consumer electronics and entertainment applications. Providing high mobility with guaranteed Quality of Service (QoS) to a WBAN user in heterogeneous wireless networks is a challenging task. A WBAN uses a Personal Digital Assistant (PDA) to gather data from body sensors and forwards it to a remote server through wide range wireless networks. In this paper, we present a coexistence study of WBAN with Wireless Local Area Networks (WLAN) and Wireless Wide Area Networks (WWANs). The main issue is interworking of WBAN in heterogenous wireless networks including seamless handover, QoS, emergency services, cooperation and security. We propose a Seamless Interworking Architecture (SIA) for WBAN in heterogenous wireless networks based on a cost function. The cost function is based on power consumption and data throughput costs. Our simulation results show that the proposed scheme outperforms typical approaches in terms of throughput, delay and packet loss rate.

  3. Wireless technologies and accessibility for people with disabilities: findings from a policy research instrument.

    PubMed

    Baker, Paul M A; Moon, Nathan W

    2008-01-01

    The near universal deployment in the United States of a wide variety of information and communications technologies, both wired and wireless, creates potential barriers to use for several key populations, including the poor, people with disabilities, and the aging. Equal access to wireless technologies and services can be achieved through a variety of mechanisms, including legislation and regulations, market-based solutions, and awareness and outreach-based approaches. This article discusses the results of policy research conducted by the Rehabilitation Engineering Research Center on Wireless Technologies (Wireless RERC) using policy Delphi polling methodology to probe stakeholders' opinions on key access barrier issues and to explore potential policy responses. Participants included disability advocates, disability/wireless technology policy makers, and product developers/manufacturers. Respondent input informed subsequent development of potential policy initiatives to increase access to these technologies. The findings from the Delphi suggest that awareness issues remain most important, especially manufacturer awareness of user needs and availability of consumer information for selecting the most appropriate wireless devices and services. Other key issues included the ability of people with disabilities to afford technologies and inadequacies in legislation and policy making for ensuring their general accessibility, as well as usefulness in emergencies. Technical issues, including interoperability, speech-to-text conversion, and hearing aid compatibility, were also identified by participating stakeholders as important. To address all these issues, Delphi respondents favored goals and options congruent with voluntary market-driven solutions where possible but also supported federal involvement, where necessary, to aid this process.

  4. [The Development of Information Centralization and Management Integration System for Monitors Based on Wireless Sensor Network].

    PubMed

    Xu, Xiu; Zhang, Honglei; Li, Yiming; Li, Bin

    2015-07-01

    Developed the information centralization and management integration system for monitors of different brands and models with wireless sensor network technologies such as wireless location and wireless communication, based on the existing wireless network. With adaptive implementation and low cost, the system which possesses the advantages of real-time, efficiency and elaboration is able to collect status and data of the monitors, locate the monitors, and provide services with web server, video server and locating server via local network. Using an intranet computer, the clinical and device management staffs can access the status and parameters of monitors. Applications of this system provide convenience and save human resource for clinical departments, as well as promote the efficiency, accuracy and elaboration for the device management. The successful achievement of this system provides solution for integrated and elaborated management of the mobile devices including ventilator and infusion pump.

  5. Apparatus for fixing latency

    DOEpatents

    Hall, David R [Provo, UT; Bartholomew, David B [Springville, UT; Moon, Justin [Bountiful, UT; Koehler, Roger O [Provo, UT

    2009-09-08

    An apparatus for fixing computational latency within a deterministic region on a network comprises a network interface modem, a high priority module and at least one deterministic peripheral device. The network interface modem is in communication with the network. The high priority module is in communication with the network interface modem. The at least one deterministic peripheral device is connected to the high priority module. The high priority module comprises a packet assembler/disassembler, and hardware for performing at least one operation. Also disclosed is an apparatus for executing at least one instruction on a downhole device within a deterministic region, the apparatus comprising a control device, a downhole network, and a downhole device. The control device is near the surface of a downhole tool string. The downhole network is integrated into the tool string. The downhole device is in communication with the downhole network.

  6. A novel optical single-sideband frequency translation technique for transmission of wireless MIMO signals over fiber-wireless system

    NASA Astrophysics Data System (ADS)

    Shaddad, Redhwan Q.; Mohammad, Abu Bakar; Al-Hetar, Abdulaziz M.; Al-Gailani, Samir A.

    2013-04-01

    The fiber-wireless (FiWi) access network is a powerful hybrid architecture of optical backhaul and wireless front-end to support high data rates and throughput with minimal time delay. By using radio over fiber (ROF) technique, the optical fiber is well adapted to propagate multiple wireless services having different carrier frequencies. However, multiple wireless signals which have the same carrier frequency cannot propagate over a single optical fiber on the same wavelength, such as multi-input multi-output (MIMO) signals. A novel optical single-sideband frequency translation technique is designed and simulated to solve this problem. 240 Mb/s 802.11n MIMO signals are proposed to transport over FiWi system using the proposed approach at 2.4 GHz and 5.0 GHz carrier frequencies. The crosstalk between MIMO signals with the same carrier frequency is excluded, since each MIMO signal is carried on a specific optical wavelength. Error vector magnitude (EVM) values of -29.83 dB (for 2.4 GHz) and -28.41 dB (for 5.0 GHz) have been achieved for bit error rate (BER) 10-5 in the proposed FiWi system.

  7. Enhanced resolution of passive wireless conductivity sensors

    NASA Astrophysics Data System (ADS)

    Kim, JinYoung; Pasupathy, Praveenkumar; Wood, Sharon L.; Neikirk, Dean P.

    2012-04-01

    A passive, wireless sensor has been developed at the University of Texas at Austin to monitor the insitu conductivity of concrete within civil infrastructure systems. Electrical conductivity is one possible indicator of corrosion of embedded reinforcement and thereby provides information on structural performance. The sensors would be attached to the reinforcement cages before placement of the concrete and interrogated as part of a routine inspection over the service life. A new sensor design, a non-contact conductivity sensor, is being developed to minimize the likelihood of damage to the sensor during placement of the concrete; a metal element is positioned above the sensor body but is not connected to the resonant circuit within the sensor. In order to verify the response of the non-contact conductivity sensors, they were submerged in liquids of increasing conductivity. Analysis of the measured data demonstrated that the noncontact conductivity sensors successfully detected conductivity variations in liquids.

  8. Energy efficiency in wireless communication systems

    DOEpatents

    Caffrey, Michael Paul; Palmer, Joseph McRae

    2012-12-11

    Wireless communication systems and methods utilize one or more remote terminals, one or more base terminals, and a communication channel between the remote terminal(s) and base terminal(s). The remote terminal applies a direct sequence spreading code to a data signal at a spreading factor to provide a direct sequence spread spectrum (DSSS) signal. The DSSS signal is transmitted over the communication channel to the base terminal which can be configured to despread the received DSSS signal by a spreading factor matching the spreading factor utilized to spread the data signal. The remote terminal and base terminal can dynamically vary the matching spreading factors to adjust the data rate based on an estimation of operating quality over time between the remote terminal and base terminal such that the amount of data being transmitted is substantially maximized while providing a specified quality of service.

  9. Energy-efficient adaptive modulation in wireless communication for implanted medical devices.

    PubMed

    Qiu, Yinyue; Haley, David; Chen, Ying

    2014-01-01

    In contrast to conventional wireless communication which takes place over the air, Radio Frequency (RF) communication through the human body poses unique challenges. Studies on RF propagation through human body indicate that the heterogeneous body tissues with different dielectric properties constitute a complicated and lossy environment for signal propagation. This environment also varies with different implant positions, individuals, body shapes and postures. As a result, there is a large variation in the path loss value of the in-body communication channel. In this paper, we first examine the energy efficiency of different digital modulation schemes in a basic wireless implant system. We point out that using a fixed type of modulation does not help to achieve the best energy efficiency in the implant system that has varying channel conditions. We then propose an adaptive communication system model which is suitable for wireless medical implant. Simulations results show that adopting adaptive modulation can provide a considerable amount of energy saving.

  10. Design and Performance Analysis of an ARQ Scheme for Broadband Wireless Access

    NASA Astrophysics Data System (ADS)

    Gürbüz, Özgür

    This paper presents design and analysis of an Automatic Repeat reQuest (ARQ) scheme for enhancing the throughput and reliability of broadband wireless access systems. The impact of ARQ is emphasized in terms of early error recovery, when Internet data applications and the TCP protocol are considered over a point-to-multipoint fixed wireless system. A selective repeat type ARQ scheme is designed and analyzed through extensive, realistic modeling and simulation of the entire network protocol stack and the wireless channel. The system-wide impact of ARQ design is quantified in terms of end-to-end delay, throughput and SNR gain and in all these metrics, significant performance improvement is observed. Enhanced features, namely, Segmentation and Reassembly (SAR) and Bitmap Compression, are proposed and shown to reduce the overhead costs.

  11. Wireless device monitoring systems and monitoring devices, and associated methods

    DOEpatents

    McCown, Steven H; Derr, Kurt W; Rohde, Kenneth W

    2014-05-27

    Wireless device monitoring systems and monitoring devices include a communications module for receiving wireless communications of a wireless device. Processing circuitry is coupled with the communications module and configured to process the wireless communications to determine whether the wireless device is authorized or unauthorized to be present at the monitored area based on identification information of the wireless device. Methods of monitoring for the presence and identity of wireless devices are also provided.

  12. Evolutionary games in wireless networks.

    PubMed

    Tembine, Hamidou; Altman, Eitan; El-Azouzi, Rachid; Hayel, Yezekael

    2010-06-01

    We consider a noncooperative interaction among a large population of mobiles that interfere with each other through many local interactions. The first objective of this paper is to extend the evolutionary game framework to allow an arbitrary number of mobiles that are involved in a local interaction. We allow for interactions between mobiles that are not necessarily reciprocal. We study 1) multiple-access control in a slotted Aloha-based wireless network and 2) power control in wideband code-division multiple-access wireless networks. We define and characterize the equilibrium (called evolutionarily stable strategy) for these games and study the influence of wireless channels and pricing on the evolution of dynamics and the equilibrium.

  13. The importance of fixed costs in animal health systems.

    PubMed

    Tisdell, C A; Adamson, D

    2017-04-01

    In this paper, the authors detail the structure and optimal management of health systems as influenced by the presence and level of fixed costs. Unlike variable costs, fixed costs cannot be altered, and are thus independent of the level of veterinary activity in the short run. Their importance is illustrated by using both single-period and multi-period models. It is shown that multi-stage veterinary decision-making can often be envisaged as a sequence of fixed-cost problems. In general, it becomes clear that, the higher the fixed costs, the greater the net benefit of veterinary activity must be, if such activity is to be economic. The authors also assess the extent to which it pays to reduce fixed costs and to try to compensate for this by increasing variable costs. Fixed costs have major implications for the industrial structure of the animal health products industry and for the structure of the private veterinary services industry. In the former, they favour market concentration and specialisation in the supply of products. In the latter, they foster increased specialisation. While cooperation by individual farmers may help to reduce their individual fixed costs, the organisational difficulties and costs involved in achieving this cooperation can be formidable. In such cases, the only solution is government provision of veterinary services. Moreover, international cooperation may be called for. Fixed costs also influence the nature of the provision of veterinary education.

  14. Wireless Communications in Reverberant Environments

    NASA Astrophysics Data System (ADS)

    Measel, Ryan Thomas

    Implementation of WLANs in reverberant environments, such as industrial facilities, naval vessels, aircraft, and spacecraft, has proven challenging, because rich electromagnetic scattering can degrade link quality through multipath interference. As a result, the adoption of Wireless LANs in these environments has been slow. Previous studies concerning reverberant environments have focused on characterizing electromagnetic properties for the purpose of electromagnetic compatibility testing. Little attention has been given to the performance of wireless communications. In this effort, the effect of electromagnetic reverberance on wireless communications is investigated in order to assess the feasibility of WLAN deployment. Work centered around two experimental measurement campaigns. The first campaign was performed in coupled reverberation chambers. The reverberation chambers provided a controllable environment which was configured to emulate the reverberance of below-deck spaces on a naval vessel. The process for quantifying and configuring the electromagnetic properties of a reverberation chamber is presented. The second campaign was performed on a naval vessel. Experimentation was conducted in a variety of locations on the ship. Locations were selected to represent a wide range of practical environments. Across both campaigns, several environment and node parameters were evaluated: level of reverberance, cavity coupling (effective aperture size), and LOS versus NLOS links. Additionally, advanced physical layer schemes and reconfigurable antennas are presented as methods to improve performance and mitigate multipath interference. To perform this work, a measurement platform and testing protocol were developed for systematic characterization of wireless communications in reverberant environments. The primary contributions of this work are empirical characterization of wireless communications in reverberant environments, approaches to improving the performance of

  15. 47 CFR 22.901 - Cellular service requirements and limitations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.901 Cellular service requirements and... operates in compliance with this section. (a) Each cellular system must provide either mobile service, fixed service, or a combination of mobile and fixed service, subject to the requirements,...

  16. Acemind new indoor full duplex optical wireless communication prototype

    NASA Astrophysics Data System (ADS)

    Bouchet, Olivier; Perrufel, Micheline; Topsu, Suat; Guan, Hongyu

    2016-09-01

    For over a century and Mr. Guglielmo Marconi invention, systems using radio waves have controlled over wireless telecommunication solutions; from Amplitude Modulation (AM) radio products to satellite communications for instance. But beyond an increasingly negative opinion face to radio waves and radio spectrum availability more and more reduced; there is an unprecedented opportunity with LED installation in displays and lighting to provide optical wireless communication solutions. As a result, technologically mature solutions are already commercially available for services such as Location Based Services (LBS), broadcast diffusion or Intelligent Transport Services (ITS). Pending finalization of the standard review process IEEE 802.15.7 r1, our paper presents the results of the European collaborative project named "ACEMIND". It offers an indoor bilateral optical wireless communication prototype having the following characteristics: use of the existing electrical infrastructure, through judicious combination with Light Fidelity (LiFi), Power Line Communication (PLC) and Ethernet to reduce the implementation cost. We propose a bilateral optical wireless communication even when the light is switched off by using Visible Light Communication (VLC) and Infra-Red Communication (IRC) combined to a remote optical switch. Dimensionally optimized LiFi module is presented in order to offer the possibility for integration inside a laptop. Finally, there is operational mechanism implementation such as OFDM/DMT to increase throughput. After the introduction, we will present the results of a market study from Orange Labs customers about their opinion on LiFi components. Then we will detail the LiFi prototype, from the physical layer aspect to MAC layer before concluding on commercial development prospects.

  17. Wireless Technologies Implications for Power Systems

    SciTech Connect

    Fuhr, Peter L; Manges, Wayne W; Schweitzer, Patrick; Kagan, Hesh

    2010-01-01

    Wireless technologies have advanced well beyond simple SCADA radio systems and point-to-point links. The current applications supported by industrial-grade wireless sensors and systems range from field measurements (classic I/O) to voice, video, asset tracking, mobile operators, etc. Which such a wide array of supported applications, the belief that wireless technology will only impact power systems in terms of wireless sensors is shortsighted. This paper, coauthored by a group of individuals intimately involved in the general realm of industrial wireless , presents a simple snapshot of current radio technologies that are used (or seriously contemplated for use) in power systems.

  18. WIRELESS FOR A NUCLEAR FACILITY

    SciTech Connect

    Shull, D; Joe Cordaro, J

    2007-03-28

    The introduction of wireless technology into a government site where nuclear material is processed and stored brings new meaning to the term ''harsh environment''. At SRNL, we are attempting to address not only the harsh RF and harsh physical environment common to industrial facilities, but also the ''harsh'' regulatory environment necessitated by the nature of the business at our site. We will discuss our concepts, processes, and expected outcomes in our attempts to surmount the roadblocks and reap the benefits of wireless in our ''factory''.

  19. Wireless Augmented Reality Communication System

    NASA Technical Reports Server (NTRS)

    Devereaux, Ann (Inventor); Jedrey, Thomas (Inventor); Agan, Martin (Inventor)

    2015-01-01

    A portable unit is for video communication to select a user name in a user name network. A transceiver wirelessly accesses a communication network through a wireless connection to a general purpose node coupled to the communication network. A user interface can receive user input to log on to a user name network through the communication network. The user name network has a plurality of user names, at least one of the plurality of user names is associated with a remote portable unit, logged on to the user name network and available for video communication.

  20. Wireless Augmented Reality Communication System

    NASA Technical Reports Server (NTRS)

    Devereaux, Ann (Inventor); Jedrey, Thomas (Inventor); Agan, Martin (Inventor)

    2017-01-01

    A portable unit is for video communication to select a user name in a user name network. A transceiver wirelessly accesses a communication network through a wireless connection to a general purpose node coupled to the communication network. A user interface can receive user input to log on to a user name network through the communication network. The user name network has a plurality of user names, at least one of the plurality of user names is associated with a remote portable unit, logged on to the user name network and available for video communication.