Sample records for mobile communications research

  1. Future Directions for Mobile Communications Business, Technology and Research

    Microsoft Academic Search

    Juha Rapeli

    2001-01-01

    This paper presents a picture of the mobile communications market and expected further development of systems and technologies. This is done with evaluating the market needs and reflecting these to available technology as well as technological opportunities. Despite of apparently advanced state of the technology and business, both market and technical solutions are concluded to likely experience further radical changes.

  2. Communication Research, the Rockefeller Foundation, and Mobilization for the War on Words, 1938-1944.

    ERIC Educational Resources Information Center

    Gary, Brett

    1996-01-01

    Argues that Rockefeller Foundation served as an unofficial arm of the state from 1938 to 1944 by mobilizing social-scientific expertise to fight fascism when the Roosevelt Administration was politically unable to do so. Notes that Rockefeller Foundation officer John Marshall's role in the history of American mass communication research and the…

  3. University of Plymouth,University of Plymouth, SoCCESoCCE, Mobile Communications Research Group, Mobile Communications Research Group Dr Mosa Ali AbuDr Mosa Ali Abu--RgheffRgheff --ENFERENFER JulienJulien INC2004INC2004

    E-print Network

    Abu-Rgheff, Mosa Ali

    , Mobile Communications Research Group Dr Mosa Ali AbuDr Mosa Ali Abu--RgheffRgheff -- ENFERENFER Julien Communications Research Group Dr Mosa Ali AbuDr Mosa Ali Abu--RgheffRgheff -- ENFERENFER JulienJulien INC2004INC Ali AbuDr Mosa Ali Abu--RgheffRgheff -- ENFERENFER JulienJulien INC2004INC2004 Seamless Communications

  4. Channel Simulation to Facilitate Mobile-Satellite Communications Research

    Microsoft Academic Search

    Faramaz Davarian

    1987-01-01

    In designing a mobile satellite network, engineers and technologists are faced with wide-ranging issues for which there is no prior database. System engineers must address such issues as adequate margin to combat multipath fading, the level of adjacent channel protection required to allow transmission in narrow-band channels, the cochannel protection required to allow for frequency reuse in a multiplebeam system,

  5. Electronic data capture platform for clinical research based on mobile phones and near field communication technology.

    PubMed

    Morak, Jürgen; Schwetz, Verena; Hayn, Dieter; Fruhwald, Friedrich; Schreier, Gunter

    2008-01-01

    Electronic data capture systems support data acquisition for clinical research and enable the evaluation of new investigational medical devices. In case of evaluating a device the most challenging part is the user interface i.e. the solution how to acquire the data within a clinical setting and to synchronize them with a web-based data centre. The aim of this paper is to describe the development of an electronic data capture system with a mobile data input solution based on mobile phones and Near Field Communication technology. This system was evaluated within a real clinical setting and demonstrated high usability, security and reliability. PMID:19163922

  6. Research on the Radiation Field of Mono-radiation Wide-Band Leaky Coaxial Cable Using for 3G Mobile Communication

    Microsoft Academic Search

    Guojian Yang; Zhuo Wang

    \\u000a To solve the problem of shortage of low frequencies along with the development of mobile communication, the research on the\\u000a leaky communication system using for the mobile communication in blind and semi-blind zone was towards to high frequency and\\u000a wide frequency area. Combining with the 3G and 2G mobile communication frequency band, the method of expanding the frequency\\u000a range of

  7. Mobile satellite communications

    Microsoft Academic Search

    W. W. Wu; E. F. Miller; W. L. Pritchard; R. L. Pickholtz

    1994-01-01

    The paper presents an up-to-date overview as well as new results on mobile satellite communications. Specifically, the following subjects are addressed: worldwide activities; satellite orbits; multiple access techniques; Novstar global positioning system; economic and regulatory issues; future trends. Some of these technical and nontechnical subjects appeal disjoint, but they are unique and significant among the many facets, which effect the

  8. Terrestrial mobile communications

    NASA Astrophysics Data System (ADS)

    Rogard, R.; Steciw, A.

    1986-11-01

    Current and future mobile communications services in Europe are described, along with the technologies for meeting the market needs. A 450 MHz cellular system began operations in Scandinavian countries in 1981, and two 900 MHz systems entered service in the United Kingdom in 1985. Similar systems are being implemented in most European countries. Coding and access schemes are being studied for a pan-European 900 MHz system. Satellites can complement the system by providing service in coastal waters, regions of economic importance to Europe, and sparsely-populated areas. Improvements in vocodors, receiver gain, and technologies for the less-congested 14/11 or 30/20 GHz voice and data links are necessary. ESA studies with the Marecs satellite, preparatory to launch of a prototype mobile communication link, are summarized.

  9. Application of mobile router to military communications

    Microsoft Academic Search

    David H. Stewart; William D. Ivancic; Terry L. Bell; Brian A. Kachmar; D. Shell; K. Leung

    2001-01-01

    Cisco Systems and NASA Glenn Research Center under a NASA Space Act Agreement have been performing joint networking research to apply Internet technologies and protocols to space-based communications. During this time, Cisco Systems developed the mobile router which NASA and Cisco jointly tested. The early field trials of this technology have been successfully completed. The mobile router is software code

  10. Going Places: Exploring the Impact of Intra-Sectoral Mobility on Research Productivity and Communication Behaviors in Japanese Academia

    ERIC Educational Resources Information Center

    Horta, Hugo; Yonezawa, Akiyoshi

    2013-01-01

    This study analyzes the impact of intra-sectoral mobility of academics on research productivity and R&D information exchange dynamics in Japan. The analysis shows intra-sectoral mobility impacting positively both research productivity and information exchange dynamics, but that this effect--except for information exchange with peers based…

  11. Smart Cards for Mobile Communications

    Microsoft Academic Search

    Keith Mayes; Tim Evans

    There are well over 2 billion smart cards in use today within mobile communications devices. The cards known as Subscriber\\u000a Identity Modules ((U)SIMs) represent some of the most technically advanced smart cards that have ever been deployed. Their\\u000a original role was to safeguard the system security by providing authentication and confidentiality, but they have evolved\\u000a to support additional security and

  12. Interference analysis for an Aeronautical Mobile Airport Communications System

    Microsoft Academic Search

    Jeffrey D. Wilson; Robert J. Kerczewski

    2011-01-01

    The next generation of aeronautical communications for airport surface applications has been identified through a NASA research program and an international collaborative future communications study. The result, endorsed by both the United States and European regulatory agencies is called AeroMACS (Aeronautical Mobile Airport Communications System) and is based upon the IEEE 802.16e mobile wireless standard. Coordinated efforts to develop appropriate

  13. Personal mobile communications in microwave band

    Microsoft Academic Search

    Yuji Kitahara

    1993-01-01

    The mobile communications technologies have been extremely-evolved during the past few years. The various types of mobile communications services such as mobile telephone, paging, teleterminal and so-on are in operation in many countries. The analogue cellular system is migrating to the digital cellular system and the high speed data services in the paging system will be launched in the near

  14. Les interfaces intelligentes et les communications mobiles

    E-print Network

    Paris-Sud XI, Université de

    Chapitre 7 Les interfaces intelligentes et les communications mobiles Badr Benmammar Laboratoire #12;Les interfaces intelligentes et les communications mobiles 3 Le reste de ce chapitre est organisé communicants : mobilité, sécurité, autonomie (Traité IC2, série réseaux et télécoms) Lavoisier librairie (Ed

  15. Electronic data capture platform for clinical research based on mobile phones and Near Field Communication technology

    Microsoft Academic Search

    Jurgen Morak; Verena Schwetz; Dieter Hayn; Friedrich Fruhwald; Gunter Schreier

    2008-01-01

    Electronic data capture systems support data acquisition for clinical research and enable the evaluation of new investigational medical devices. In case of evaluating a device the most challenging part is the user interface i.e. the solution how to acquire the data within a clinical setting and to synchronize them with a web-based data centre. The aim of this paper is

  16. A review of mobile satellite communication systems

    NASA Astrophysics Data System (ADS)

    Kondo, Kimio

    1990-03-01

    This article describes mobile satellite systems in the planning or development stage such as MSAT, AMSC and Geostar and mobile satellite communication experiments such as PRODAT. Studies on the system such as T-SAT are also reviewed. In addition, Japanese ETS-V and ETS-VI are described. The development of mobile-satellite communication systems is promoted along with those of communication and satellite technologies.

  17. Satellite communication and navigation for mobile users

    NASA Technical Reports Server (NTRS)

    Bernstein, S. L.

    1972-01-01

    Efforts made to utilize space technology for solving communication and navigation problems faced by mobile users in earth orientated situations are outlined. Applications include transoceanic airline communications, reliable long range ship-shore communications, emergency communications in regions with rough terrain, and military operations.

  18. Antennas for mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Huang, John

    1991-01-01

    A NASA sponsored program, called the Mobile Satellite (MSAT) system, has prompted the development of several innovative antennas at L-band frequencies. In the space segment of the MSAT system, an efficient, light weight, circularly polarized microstrip array that uses linearly polarized elements was developed as a multiple beam reflector feed system. In the ground segment, a low-cost, low-profile, and very efficient microstrip Yagi array was developed as a medium-gain mechanically steered vehicle antenna. Circularly shaped microstrip patches excited at higher-order modes were also developed as low-gain vehicle antennas. A more recent effort called for the development of a 20/30 GHz mobile terminal antenna for future-generation mobile satellite communications. To combat the high insertion loss encountered at 20/30 GHz, series-fed Monolithic Microwave Integrated Circuit (MMIC) microstrip array antennas are currently being developed. These MMIC arrays may lead to the development of several small but high-gain Ka-band antennas for the Personal Access Satellite Service planned for the 2000s.

  19. Experiment In Aeronautical-Mobile/Satellite Communication

    NASA Technical Reports Server (NTRS)

    Jedrey, Thomas C.; Lay, Norman E.; Dessouky, Khaled

    1992-01-01

    Report describes study of performance of digital mobile/satellite communication terminals of advanced design intended for use in ground stations and airplanes in aeronautical-mobile service. Study was collaboration of NASA, Federal Aviation Administration (FAA), Communications Satellite Corp. (COMSAT), and International Maritime Satellite System (INMARSAT).

  20. Department of Mobile Communications Campus Sophia Tech

    E-print Network

    Gesbert, David

    interest or providing access to resources or services between peers can enhance a mobile node . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4 Case Study: Mobile Data Offloading 15 4.1 Case 1: no QoS constraintsEURECOM Department of Mobile Communications Campus Sophia Tech Les Templiers 450 route des Chappes

  1. Effective Protocols for Mobile Communications and Networking

    SciTech Connect

    Espinoza, J.; Sholander, P.; Van Leeuwen, B,

    1998-12-01

    This report examines methods of mobile communications with an emphasis on mobile computing and wireless communications. Many of the advances in communications involve the use of Internet Protocol (IP), Asynchronous Transfer Mode (ATM), and ad hoc network protocols. However, many of the advances in these protocols have been focused on wired communications. Recently much focus has been directed at advancing communication technology in the area of mobile wireless networks. This report discusses various protocols used in mobile communications and proposes a number of extensions to existing protocols. A detailed discussion is also included on desirable protocol characteristics and evaluation criteria. In addition, the report includes a discussion on several network simulation tools that maybe used to evaluate network protocols.

  2. Mailbox-based scheme for mobile agent communications

    Microsoft Academic Search

    Jiannong Cao; Xinyu Feng; Jian Lu; Sajal K. Das

    2002-01-01

    In various situations, mobile agents at different hosts must cooperate with one another by sharing information and making decisions collectively. To ensure effective interagent communication, communication protocols must track target agent locations and deliver messages reliably. Researchers have proposed a wide range of schemes for agent tracking and reliable message delivery. However, each scheme has its own assumptions, design goals,

  3. Effectively Communicating Qualitative Research

    ERIC Educational Resources Information Center

    Ponterotto, Joseph G.; Grieger, Ingrid

    2007-01-01

    This article is a guide for counseling researchers wishing to communicate the methods and results of their qualitative research to varied audiences. The authors posit that the first step in effectively communicating qualitative research is the development of strong qualitative research skills. To this end, the authors review a process model for…

  4. Mobile Phones as Fashion Statements: The Co-creation of Mobile Communication’s Public Meaning

    Microsoft Academic Search

    James E. Katz; Satomi Sugiyama

    This chapter explores public mobile communication technology as frontstage and back-stage phenomena. We explore the design aesthetics of the mobile phone from the standpoint of its commercial origins and public re-interpretation, emphasizing fashion and identity in the co-creation and consumption of mobile communication technology. The mobile phone in this context is analyzed as both a physical icon and an item

  5. Context-Aware Dynamic Security Configuration for Mobile Communication Device

    Microsoft Academic Search

    Gaeil An; Guntae Bae; Kiyoung Kim; Dongil Seo

    2009-01-01

    A mobile communication device is a small size of portable computer which provides communication service. One of the biggest barriers in developing the mobile communication device is security. To protect itself against security threats, the mobile communication device need to be loaded with various kinds of security functions such as firewall, access control, and so on. However because the mobile

  6. Spread spectrum mobile radio communications

    NASA Astrophysics Data System (ADS)

    Gupta, S. C.; Sandeep, C.; Refai, W.

    1989-09-01

    Two problems are studied. The first is concerned with evaluating the performance of a class of bandwidth efficient modulation schemes in a frequency reuse mobile radio channel. The second problem is concerned with formulating and evaluating the performance of a class of known delay multipath diversity receivers for indoor wireless communication. Several partial response (PRCPM) schemes such as TFM, GMSK and 3RC are compared with regard to their performance in the presence of Adjacent Channel Interference (ACI) and CoChannel Interference (CCI). The performance criteria chosen were average probability of bit error and mean-square cross talk ratio. A comparison of three receiver filters with regard to their ability to reject ACI is also provided. Results indicate that receiver filter length is very important parameter for good performance. The performance of PRCPM schemes is analyzed by considering the combined effects of ACI, CCI and Rayleigh fading. The analysis is extended to the case when space diversity is employed. Results indicate that by using space diversity and maximal Ration Combining significant performance gains can be achieved.

  7. EECE 569 -UBC ECE -Outline Outline-1 Mobile Communications Networks

    E-print Network

    Pulfrey, David L.

    Wireless wireline interworking Mobile IP Simulations of wireless networks Security in wireless networksEECE 569 - UBC ECE - Outline Outline-1 EECE 569 Mobile Communications Networks http Objectives Aspects of mobile communications networks Architectures, protocols and management techniques

  8. Multihop communications in future mobile radio networks

    Microsoft Academic Search

    H. Li; M. Lott; M. Weckerle; W. Zirwas; E. Schulz

    2002-01-01

    Cellular networks and wireless local area networks (WLAN) are being widely deployed for mobile radio communications. Taking into account the advantageous and drawbacks of both network architectures, it becomes obvious that a combination of them is the logical consequence for future mobile radio networks. The scope of this paper is to introduce a future radio network architecture called hierarchical multihop

  9. Repeated Transmissions In Mobile/Satellite Communications

    NASA Technical Reports Server (NTRS)

    Yan, Tsun-Yee; Clare, Loren P.

    1988-01-01

    Repetition increases throughput and decreases delay. Paper discusses theoretical performance of communication system for land-mobile stations with satellite relay using ALOHA random-access protocol modified for repeated transimssions. Methods and conclusions contribute to general understanding of packet communications in fading channels.

  10. LOW COST RECONFIGURABLE HARDWARE ARCHITECTURE FOR SECURE MOBILE COMMUNICATION

    Microsoft Academic Search

    G. Uma Maheswari; B. Venkatramanan; Mothi V. Sabaresan

    Mobile communication is presently used by large number of people and Global System for Mobile Communication (GSM) is the most widely used cellular mobile phone system in the world. In mobile communications, cryptography techniques are used extensively for secure transmission and reception of data. Cryptanalysis has become a challenging task as crypto algorithm becoming stronger with advent of supercomputing power

  11. Value in technology evolution: case mobile peer-to-peer communications

    Microsoft Academic Search

    Mikko V. J. Heikkinen; Sakari Luukkainen

    2010-01-01

    Purpose – Mobile peer-to-peer communications is an essential phase in the evolution of mobile communications technologies, motivating this research which aims to focus on how established industry stakeholders and new entrants can adapt themselves to the new situation. Design\\/methodology\\/approach – Based on existing literature, the authors identified three distinctive evolution paths for mobile peer-to-peer communications and developed an analysis framework

  12. Satellite multiple access systems for mobile communication

    NASA Technical Reports Server (NTRS)

    Lewis, J. L.

    1979-01-01

    This paper considers multiple access techniques for a mobile radio system which incorporates a geosynchronous orbiting satellite repeater through which mobile terminals communicate. The communication capacities of FDMA, TDMA and CDMA systems are examined for a 4 MHz bandwidth system to serve up to 10,000 users. An FDMA system with multibeam coverage is analyzed in detail. The system includes an order-wire network for demand-access control and reassignment of satellite channels. Satellite and terminal configurations are developed to a block diagram level and system costs and implementation requirements are discussed.

  13. Anonymous communications in mobile ad hoc networks

    Microsoft Academic Search

    Yanchao Zhang; Wei Liu; Wenjing Lout

    2005-01-01

    Abstract—Due to the broadcast nature of radio transmissions, communications in mobile ad hoc networks (MANETs) are more susceptible to malicious traffi ca nalysis. In this paper we propose a novel anonymous on-demand routing protocol, termed MASK, to enable anonymous,communications thereby thwarting possible traffic analysis attacks. Based on a new cryptographic concept called pairing, we first propose an anonymous neighborhood authentication

  14. Advanced mobile satellite communications using COMETS satellite in MM-wave and Ka-band

    Microsoft Academic Search

    Shingo Ohmori; Shunkichi Isobe; Makoto Takeuchi; Hideyuki Naito

    1993-01-01

    Early in the 21st century, the demand for personal communications using mobile, hand-held, and VSAT terminals will rapidly increase. In a future system, many different types of services should be provided with one-hop connection. The Communications Research Laboratory (CRL) has studied a future advanced mobile satellite communications system using millimeter wave and Ka band. In 1990, CRL started the Communications

  15. Time reversal communication with a mobile source.

    PubMed

    Song, H C

    2013-10-01

    Broadband underwater acoustic communication signals undergo either a compression or dilation in the presence of relative motion between a source and a receiver. Consequently, underwater acoustic communications with a mobile source/receiver require Doppler compensation through resampling. However, resampling may not be necessary when a channel-estimate-based time reversal approach is applied with frequent channel updates. Using experimental data (20-30 kHz), it is demonstrated that the performance of time reversal communication without resampling is similar to the case with resampling, along with the benefit of a modest computational saving. PMID:24116398

  16. Communicating and Mobile Systems: The ?-calculus

    Microsoft Academic Search

    Robin Milner

    1999-01-01

    The pi-calculus differs from other models of communicating behaviour mainly in its treatment of mobility. The movement of a piece of data inside a computer program is treated exactly the same as the transfer of a message - or indeed an entire computer program - across the internet. One can also describe networks which reconfigure themselves. The calculus is very

  17. WIRELESS COMMUNICATIONS MOBILE COMPUTING Wirel. Commun. Comput.

    E-print Network

    Giannakis, Georgios

    broadband wireless communications. survey space -- time coding schemes is provided this paper. Targeting references therein). these systems, exceed Mbps while mobile units may move as a high­speed train with user combat fading exploitation diversity. Accord­ domain where diversity is created, diversity techniques may

  18. Mobile Communication Security Controllers An Evaluation Paper

    E-print Network

    Mayes, Keith

    Mobile Communication Security Controllers An Evaluation Paper Keith E. Mayes, Konstantinos that types of "Software SIM" should be used as an alternative to the smart card based solution. This paper and services against criminal mis-use remains and indeed has become more acute as electronic applications

  19. Secure asynchronous communication for mobile devices

    Microsoft Academic Search

    Pierre Henri Kuaté; Johnny Li-Chang Lo; Judith Bishop

    2009-01-01

    Mobile devices are now used not only for communication but also as working units. As more sensitive information is stored on and transmitted through these devices, security is becoming a growing concern. This is especially true for SMS messages which do not integrate any security mechanism. This is why we propose a simple-to-use but cryptographically strong API for message encryption

  20. Advanced mobile satellite communications using COMETS satellite in MM-wave and Ka-band

    NASA Technical Reports Server (NTRS)

    Ohmori, Shingo; Isobe, Shunkichi; Takeuchi, Makoto; Naito, Hideyuki

    1993-01-01

    Early in the 21st century, the demand for personal communications using mobile, hand-held, and VSAT terminals will rapidly increase. In a future system, many different types of services should be provided with one-hop connection. The Communications Research Laboratory (CRL) has studied a future advanced mobile satellite communications system using millimeter wave and Ka band. In 1990, CRL started the Communications and Broadcasting Engineering Test Satellite (COMETS) project. The satellite has been developed in conjunction with NASDA and will be launched in 1997. This paper describes the COMETS payload configuration and the experimental system for the advanced mobile communications mission.

  1. Development of antenna system for S-band mobile satellite communications and broadcasting

    Microsoft Academic Search

    Ken-ichi Haryu; Yasuhiko Yamasa; Teruki Okamoto; Yuichi Otsu; Kazuhiko Yoneyama

    1996-01-01

    Advanced Space Communications Research Laboratory is studying an antenna system for future S-band mobile satellite communication and broadcasting. This system uses a GEO satellite and is composed of a large deployable satellite antenna with a 10 m diameter mesh reflector and a mobile antenna for vehicles and hand-held terminals. In this paper, we present our deployable satellite antenna program and

  2. Modelling of handover of multimedia traffic in mobile satellite communication

    Microsoft Academic Search

    A. Sali; N. K. Noordin; B. M. Ali; R. K. Z. Sahbudin; A. Anthony; Ng Chee Kyun

    2002-01-01

    This paper presents the handover management in mobile satellite communications with multimedia traffic. Multimedia traffic is becoming the next hop in mobile satellite communication, due to its demand. The coverage of the satellite network knows no boundary and with the concept of the broadband satellite network, communication for multimedia and high-data rate multimedia communications can be provided. The handover initiation

  3. Spread spectrum mobile radio communications

    NASA Astrophysics Data System (ADS)

    Gupta, S. C.

    1982-12-01

    In this report, we analyze the performance of frequency-hopped spread-spectrum systems under mobile radio channel conditions. Because of its good spectrum-efficiency, frequency-hopped systems seen to be natural candidates for mobile telephony in the near future. We analyze mainly the Frequency-Hopped-Multilevel Frequency Shift-Keyed (FH-MFSK) System, the reason being the established superiority of FH-MFSK over the other modulation, namely the Frequency-Hopped Differential Phase Shift Keyed system (FH-DPSK), under identical conditions. Our new results include the spectrum efficiency analysis of FH-MFSK for various bandwidths of interest, the performance analysis of FH-MFSK under the influence of log-normal shadowing and Rayleigh fading, the possible performance improvement with the inclusion of a small number of space-diversity branches to combat the losses due to fading, a preliminary analysis of the occurrence of burst errors in FH systems, the amount of degradation due to the users operating in the adjacent cells and a possible power control scheme to mitigate these effects and finally a result which establishes the near-equivalent performance of the hard-limited and the likelihood receivers under Rayleigh fading and multi-user interference conditions.

  4. Near Field Communication im Mobile Marketing

    Microsoft Academic Search

    K.-P. Wiedmann; M.-O. Reeh; H Schumacher

    Near Field Communication (NFC) ist eine Kurzstrecken-Funktechnologie für die anwenderfreundliche Vernetzung mobiler Endgeräte\\u000a wie Handys, PDAs und Smartphones untereinander sowie mit feststehenden Einheiten wie Kunden- oder EC-Terminals. Technisch\\u000a eng verwandt mit kontaktlosen Chipkarten und den jüngst vieldiskutierten Radio Frequency Identification-Systemen (RFID) wollen\\u000a Gerätehersteller, Netzbetreiber und Serviceprovider NFC in Zukunft verstärkt dazu nutzen, interessierten Mobilfunkkunden neue\\u000a Dienste zu offerieren, die dem

  5. National Security, Forensics and Mobile Communications

    Microsoft Academic Search

    David Naccache

    2005-01-01

    \\u000a There are nearly 1.5 billion handset users in the world. As the recent attacks in London illustrate, this proliferation of\\u000a inexpensive mobile phones provides criminals and terrorists with flexible communication means. In this talk we will describe\\u000a the forensic methodology used for analysing SIM cards and handsets within the French legal context. We will describe specific\\u000a technical problems applicable to

  6. Exploiting Doppler Diversity In Mobile Wireless Communications

    Microsoft Academic Search

    Akbar M. Sayeed; Behnaam Aazhang

    1997-01-01

    Signal fading due to variations in channel characteristicsis one of the major factors limiting the performance ofmodern mobile wireless communication systems. To overcomefading, various diversity techniques have been developedthat effectively transmit multiple copies of the signalover the channel. The state-of-the-art receiver used incode-division multiple access systems is the RAKE receiverthat exploits multipath diversity. However, the RAKE receiverassumes slow channel variations

  7. Ray-Tracing for Mobile Communications

    Microsoft Academic Search

    Sandra Knorzer; Thomas Fugen; Werner Wiesbeck

    For the parametrization and standardization of future mobile communications systems realistic values of the characteristic channel parameters are needed. Due to its ability to analyze the frequency-selective, time-variant as well as spa- tial behavior of the channel, ray-tracing is a popular channel characterization method. Moreover, it is capable to calculate very large structures (i.e. site-specific scenarios) with reasonable computation resources.

  8. Robotic Communication Terminals as a Mobility Support System for Elderly and Disabled People(2)

    NASA Astrophysics Data System (ADS)

    Yairi, Ikuko Eguchi; Igi, Seiji

    We have been developing Robotic Communication Terminals (RCT) as a mobility support system for the elderly and disabled people, which assists for their impaired elements of mobility— recognition, actuation, and information access. The RCT consist of three types of terminals: “environment-embedded terminal”“user-carried mobile terminal”, and “user-carrying mobile terminal”. These terminals communicate with one another to provide the users with a comfortable means of mobility. In this paper, we introduce the overview of our research. The recent progress is also presented as well as the future plan.

  9. Design of a mobile coastal communications buoy

    E-print Network

    Hendry-Brogan, Meghan

    2004-01-01

    In response to a growing interest in networked communications at sea as well as the needs of our vital commercial fishing industry, the Northeast Consortium funded a novel research initiative to establish wireless acoustic ...

  10. Adaptive Beamforming in Mobile, Massively Multiuser Satellite Communications: A System

    E-print Network

    Gesbert, David

    Adaptive Beamforming in Mobile, Massively Multiuser Satellite Communications: A System Perspective Xiao Lei, Laura Cottatellucci, Samah A. M. Ghanem Mobile Communications Department, Eurecom, France Email: {xiao.lei; laura.cottatellucci; samah.ghanem}@eurecom.fr Abstract--We consider a Mobile Satellite

  11. The impact of digital iconic realism on anonymous interactants' mobile phone communication

    Microsoft Academic Search

    Sin-hwa Kang

    2007-01-01

    In this paper, I describe progress in research designed to explore the effect of the combination of behavioral and visual fidelity of avatars on users. social presence in synchronous and emotionally engaged mobile phone communication. I specifically focus on ways to secure mobile phone users. anonymity while preserving their most important nonverbal affective behaviors. The research measures social presence in

  12. DESIRED MOBILE APPLICATION FEATURES IN AGRICULTURAL COMMUNICATIONS AND JOURNALISM STUDENTS AT TEXAS A&M UNIVERSITY 

    E-print Network

    Meadows, Casey

    2013-02-12

    Desired Mobile Application Features In Agricultural Communications And Journalism Students At Texas A&M University. (March 2013) Casey Meadows Department of Agriculture Texas A&M University Research Advisor: Dr. Billy McKim Department...

  13. MACCS: enabling communications for mobile workers within healthcare environments

    Microsoft Academic Search

    Michael J. Sammon; Lynne Shapiro Brotman; Ed Peebles; Dorée Duncan Seligmann

    2006-01-01

    As wireless communications systems become more ubiquitous, enterprise workers are becoming more and more mobile. Addressing mobility in the enterprise has recently become a pressing concern for many corporations. In particular, there is a growing component of mobile workers whose job tasks require them to be mobile within their local workspace. These workers sometimes do not have a desk or

  14. Cluestr: mobile social networking for enhanced group communication

    Microsoft Academic Search

    Reto Grob; Michael Kuhn; Roger Wattenhofer; Martin Wirz

    2009-01-01

    Recent technological advances foster the spreading of social software in the mobile domain. Hence, future usage patterns of mobile devices will involve more group interaction. While collaboration using mobile devices is an active area of re- search, only limited attention has been paid to the efficient initiation of group communication from mobile terminals. In this paper we present a community-aware

  15. Route Optimization for Intra Communication of a Nested Mobile Network

    E-print Network

    National University hscho@mmlab.snu.ac.kr ABSTRACT Network mobility, i.e. Internet access services.11/16) and mobile communication services, the demand for Internet access in mobile vehicles such as trains, buses is referred to as network mobility (NEMO) support. To address the NEMO support problem, Internet Engineering

  16. Hybrid Mobile Communication Networks for Planetary Exploration

    NASA Technical Reports Server (NTRS)

    Alena, Richard; Lee, Charles; Walker, Edward; Osenfort, John; Stone, Thom

    2007-01-01

    A paper discusses the continuing work of the Mobile Exploration System Project, which has been performing studies toward the design of hybrid communication networks for future exploratory missions to remote planets. A typical network could include stationary radio transceivers on a remote planet, mobile radio transceivers carried by humans and robots on the planet, terrestrial units connected via the Internet to an interplanetary communication system, and radio relay transceivers aboard spacecraft in orbit about the planet. Prior studies have included tests on prototypes of these networks deployed in Arctic and desert regions chosen to approximate environmental conditions on Mars. Starting from the findings of the prior studies, the paper discusses methods of analysis, design, and testing of the hybrid communication networks. It identifies key radio-frequency (RF) and network engineering issues. Notable among these issues is the study of wireless LAN throughput loss due to repeater use, RF signal strength, and network latency variations. Another major issue is that of using RF-link analysis to ensure adequate link margin in the face of statistical variations in signal strengths.

  17. Advanced communications payload for mobile applications

    NASA Technical Reports Server (NTRS)

    Ames, S. A.; Kwan, R. K.

    1990-01-01

    An advanced satellite payload is proposed for single hop linking of mobile terminals of all classes as well as Very Small Aperture Terminal's (VSAT's). It relies on an intensive use of communications on-board processing and beam hopping for efficient link design to maximize capacity and a large satellite antenna aperture and high satellite transmitter power to minimize the cost of the ground terminals. Intersatellite links are used to improve the link quality and for high capacity relay. Power budgets are presented for links between the satellite and mobile, VSAT, and hub terminals. Defeating the effects of shadowing and fading requires the use of differentially coherent demodulation, concatenated forward error correction coding, and interleaving, all on a single link basis.

  18. Frequency addressable beams for land mobile communications

    NASA Technical Reports Server (NTRS)

    Thompson, J. D.; Dubellay, G. G.

    1988-01-01

    Satellites used for mobile communications need to serve large numbers of small, low cost terminals. The most important parameters affecting the capacity of such systems are the satellite equivalent isotropically radiated power (EIRP) and gain to noise temperature ratio (G/T) and available bandwidth. Satellites using frequency addressed beams provide high EIRP and G/T with high-gain antenna beams that also permit frequency reuse over the composite coverage area. Frequency addressing is easy to implement and compatible with low-cost terminals and offers higher capacity than alternative approaches.

  19. IEEE Communications Magazine July 199790 Rayleigh Fading Channels in Mobile

    E-print Network

    Howard, Sheryl

    IEEE Communications Magazine · July 199790 Rayleigh Fading Channels in Mobile Digital Communication of transmitted power is attenuated by a factor, Ls(d), where this factor is called path loss or free space loss

  20. Aeronautical Mobile Airport Communications System (AeroMACS)

    NASA Technical Reports Server (NTRS)

    Budinger, James M.; Hall, Edward

    2011-01-01

    To help increase the capacity and efficiency of the nation s airports, a secure wideband wireless communications system is proposed for use on the airport surface. This paper provides an overview of the research and development process for the Aeronautical Mobile Airport Communications System (AeroMACS). AeroMACS is based on a specific commercial profile of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard known as Wireless Worldwide Interoperability for Microwave Access or WiMAX (WiMax Forum). The paper includes background on the need for global interoperability in air/ground data communications, describes potential AeroMACS applications, addresses allocated frequency spectrum constraints, summarizes the international standardization process, and provides findings and recommendations from the world s first AeroMACS prototype implemented in Cleveland, Ohio, USA.

  1. The 18th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'07) IMPLEMENTING BACKSCATTER RADIO FOR WIRELESS SENSOR NETWORKS

    E-print Network

    The 18th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications Electric Research Laboratories, Cambridge USA Aggelos Bletsas RadioCommunications Lab (RCL) Aristotle backscatter is commonly used in RFID (Radio Frequency IDentification) systems. Radio backscatter communication

  2. 75 FR 3914 - Recordation of Trade Name “Sony Ericsson Mobile Communications AB”

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-25

    ...by Sony Ericsson Mobile Communications AB. The application for trade name recordation...name, Sony Ericsson Mobile Communications AB...published a notice of application for the recordation...Sony Ericsson Mobile Communications...

  3. Key Issues in Expansion of Mobile Data Communications in China

    Microsoft Academic Search

    Sunanda Sangwan; Chong Guan; Louis-Francois Pau

    2008-01-01

    China's mobile communications market presents unique market challenges. Market is experiencing a high subscriber growth rate and its implications for business and end-users and investigation into the current status of this market will improve our understanding on how adoption of mobile communications is evolving at the end-user level. In this paper we use a descriptive method to analyze key issues

  4. Interference Analysis for an Aeronautical Mobile Airport Communications System

    NASA Technical Reports Server (NTRS)

    Wilson, Jeffrey D.; Kercewski, Robert J.

    2010-01-01

    The next generation of aeronautical communications for airport surface applications has been identified through a NASA research program and an international collaborative future communications study. The result, endorsed by both the United States and European regulatory agencies is called AeroMACS (Aeronautical Mobile Airport Communications System) and is based upon the IEEE 802.16e mobile wireless standard. Coordinated efforts to develop appropriate aviation standards for the AeroMACS system are now underway within RTCA (United States) and Eurocae (Europe). AeroMACS will be implemented in a recently allocated frequency band, 5091- 5150 MHz. As this band is also occupied by fixed satellite service uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference to the fixed satellite service are under analysis in order to enable the definition of standards that assure that such interference will be avoided. The NASA Glenn Research Center has been involved in this analysis, and the first results of modeling and simulation efforts directed at this analysis are the subject of this paper.12

  5. Interference Analysis for an Aeronautical Mobile Airport Communications System

    NASA Technical Reports Server (NTRS)

    Wilson, Jeffrey D.; Kerczewski, Robert J.

    2011-01-01

    The next generation of aeronautical communications for airport surface applications has been identified through a NASA research program and an international collaborative future communications study. The result, endorsed by both the United States and European regulatory agencies is called AeroMACS (Aeronautical Mobile Airport Communications System) and is based upon the IEEE 802.16e mobile wireless standard. Coordinated efforts to develop appropriate aviation standards for the AeroMACS system are now underway within RTCA (United States) and Eurocae (Europe). AeroMACS will be implemented in a recently allocated frequency band, 5091-5150 MHz. As this band is also occupied by fixed satellite service uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference to the fixed satellite service are under analysis in order to enable the definition of standards that assure that such interference will be avoided. The NASA Glenn Research Center has been involved in this analysis, and the first results of modeling and simulation efforts directed at this analysis are the subject of this presentation.

  6. Mobile health for non-communicable diseases in Sub-Saharan Africa: a systematic review of the literature and strategic framework for research

    PubMed Central

    2014-01-01

    Background Mobile health (mHealth) approaches for non-communicable disease (NCD) care seem particularly applicable to sub-Saharan Africa given the penetration of mobile phones in the region. The evidence to support its implementation has not been critically reviewed. Methods We systematically searched PubMed, Embase, Web of Science, Cochrane Central Register of Clinical Trials, a number of other databases, and grey literature for studies reported between 1992 and 2012 published in English or with an English abstract available. We extracted data using a standard form in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Results Our search yielded 475 citations of which eleven were reviewed in full after applying exclusion criteria. Five of those studies met the inclusion criteria of using a mobile phone for non-communicable disease care in sub-Saharan Africa. Most studies lacked comparator arms, clinical endpoints, or were of short duration. mHealth for NCDs in sub-Saharan Africa appears feasible for follow-up and retention of patients, can support peer support networks, and uses a variety of mHealth modalities. Whether mHealth is associated with any adverse effect has not been systematically studied. Only a small number of mHealth strategies for NCDs have been studied in sub-Saharan Africa. Conclusions There is insufficient evidence to support the effectiveness of mHealth for NCD care in sub-Saharan Africa. We present a framework for cataloging evidence on mHealth strategies that incorporates health system challenges and stages of NCD care. This framework can guide approaches to fill evidence gaps in this area. Systematic review registration: PROSPERO CRD42014007527. PMID:24927745

  7. Land vehicle antennas for satellite mobile communications

    NASA Technical Reports Server (NTRS)

    Haddad, H. A.; Paschen, D.; Pieper, B. V.

    1985-01-01

    Antenna designs applicable to future satellite mobile vehicle communications are examined. Microstrip disk, quadrifilar helix, cylindrical microstrip, and inverted V and U crossed-dipole low gain antennas (3-5 dBic) that provide omnidirectional coverage are described. Diagrams of medium gain antenna (9-12 dBic) concepts are presented; the antennas are classified into three types: (1) electronically steered with digital phase shifters; (2) electronically switched with switchable power divider/combiner; and (3) mechanically steered with motor. The operating characteristics of a conformal antenna with electronic beam steering and a nonconformal design with mechanical steering are evaluated with respect to isolation levels in a multiple satellite system. Vehicle antenna pointing systems and antenna system costs are investigated.

  8. SAW based systems for mobile communications satellites

    NASA Technical Reports Server (NTRS)

    Peach, R. C.; Miller, N.; Lee, M.

    1993-01-01

    Modern mobile communications satellites, such as INMARSAT 3, EMS, and ARTEMIS, use advanced onboard processing to make efficient use of the available L-band spectrum. In all of these cases, high performance surface acoustic wave (SAW) devices are used. SAW filters can provide high selectivity (100-200 kHz transition widths), combined with flat amplitude and linear phase characteristics; their simple construction and radiation hardness also makes them especially suitable for space applications. An overview of the architectures used in the above systems, describing the technologies employed, and the use of bandwidth switchable SAW filtering (BSSF) is given. The tradeoffs to be considered when specifying a SAW based system are analyzed, using both theoretical and experimental data. Empirical rules for estimating SAW filter performance are given. Achievable performance is illustrated using data from the INMARSAT 3 engineering model (EM) processors.

  9. Asian Communication: Research, Training, Planning.

    ERIC Educational Resources Information Center

    Lerner, Daniel, Ed.

    A selection of eight papers on Asian communication is presented for the purpose of alerting communication researchers to significant work being done outside of the academic community. Topics include (1) a Malaysian experience in using commercial resources for audience research, (2) a content analysis model of the Pakistani press, (3) the…

  10. A generalized transmultiplexer and its application to mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Ichiyoshi, Osamu

    1990-01-01

    A generalization of digital transmultiplexer technology is presented. The proposed method can realize transmultiplexer (TMUX) and transdemultiplexer (TDUX) filter banks whose element filters have bandwidths greater than the channel spacing frequency. This feature is useful in many communications applications. As an example, a satellite switched (SS) Frequency Division Multiple Access (FDMA) system is proposed for spot beam satellite communications, particularly for mobile satellite communications.

  11. Department of Mobile Communications Campus SophiaTech

    E-print Network

    Gesbert, David

    for periodic vehicular safety communications. Index Terms LTE-Direct, broadcast, eMBMS, periodic vehicular Communications eMBMS evolved Multimedia Broadcast Multicast Service eNB evolved Node B FDD Frequency DivisionEURECOM Department of Mobile Communications Campus SophiaTech 450 Route des Chappes 06410 Biot

  12. Simulation studies of the effects of user mobility on the handoff performance of mobile communications

    Microsoft Academic Search

    Kyungsook Han

    2002-01-01

    The performance of soft handoffs of code division multiple access (CDMA) mobile communication systems is determined by several factors. Due to the importance of handoffs in mobile communications, several handoff methods have been proposed and evaluated through computer simulations. However, the credibility of simulation results depends on the objectivity of the assumptions made by the simulations. This paper presents a

  13. Mobile communications satellite antenna flight experiment definition

    NASA Astrophysics Data System (ADS)

    Freeland, Robert E.

    There are classes of application that collectively require a variety of different types of large-aperture space antennas. Fortunately, there are a number of different deployable antenna concepts that have tremendous potential for such applications. However, these concepts vary in maturity from flight-proven designs to extremely innovative configuration definitions. But these promising concepts lack sufficient demonstrations of maturity to be seriously considered in the large size range for immediate application. The reason for this situation is an extremely limited space flight data base in addition to the technical limitations and great costs associated with meaningful ground testing of large, flexible, precision space structures. The user community of such structures, especially the commercial organizations interested in providing a Mobile Communications Satellite (MSAT) on a profit-making basis, will require significant demonstrations of technology readiness prior to application commitment. Such demonstrations will probably be based on a combination of extensive ground testing and subsequent space flight experiments. The Communications Division of the National Aeronautics and Space Administration (NASA) Office of Space Science and Applications sponsored a study at the Jet Propulsion Laboratory (JPL) to determine the technical feasibility and cost of a Shuttle-based flight experiment specifically intended for the MSAT commercial user community. The experiment will include demonstrations of technology in the areas of radio frequency (RF), sensing and control, and structures. This paper summarizes the results of the structural subsystem study. These results include experiment objective and technical approach, experiment structural description, structure/environment interactions, structural characterization, thermal characterization, structural measurement system, and experiment functional description.

  14. Advanced mobile satellite communications system using Ka and MM-wave bands in Japan's R and D satellite project

    Microsoft Academic Search

    Shunkichi Isobe; Shingo Ohmori; Naokazu Hamamoto; Minoru Yamamoto

    1991-01-01

    Communications Research Laboratory (CRL) studied an advanced mobile satellite communications system using Ka and millimeter-wave bands in the R&D Satellite project. The project started in 1990 and the satellite will be launched in 1997. On-board multi-beam interconnecting is one of basic functions to realize one-hop connection among Very Small Aperture Terminals (VSATs), mobile, and hand-held terminals in future mobile satellite

  15. 78 FR 69018 - Improving the Resiliency of Mobile Wireless Communications Networks; Reliability and Continuity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-18

    ...FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 4 [PS Docket...the Resiliency of Mobile Wireless Communications Networks; Reliability and Continuity of Communications Networks, Including Broadband...

  16. Secure Communication and Access Control for Mobile Web Service Provisioning

    E-print Network

    Srirama, Satish Narayana

    2010-01-01

    It is now feasible to host basic web services on a smart phone due to the advances in wireless devices and mobile communication technologies. While the applications are quite welcoming, the ability to provide secure and reliable communication in the vulnerable and volatile mobile ad-hoc topologies is vastly becoming necessary. The paper mainly addresses the details and issues in providing secured communication and access control for the mobile web service provisioning domain. While the basic message-level security can be provided, providing proper access control mechanisms for the Mobile Host still poses a great challenge. This paper discusses details of secure communication and proposes the distributed semantics-based authorization mechanism.

  17. Bandwidth Efficient Turbo Coding For High Speed Mobile Satellite Communications

    Microsoft Academic Search

    Mark Rice; Paul Gray; S. Adrian Barbulescu; Wade Farrell

    1997-01-01

    ABSTRACT This paper describes an application of turbo codes in conjunction with 16QAM in high speed mobile satellite communications The channel characteristics, the architecture of the modem and the performance curves for the selected turbo codes are presented

  18. Podscanning : audio microcontent and synchronous communication for mobile devices

    E-print Network

    Wheeler, Patrick Sean

    2010-01-01

    Over the past decade, computationally powerful audio communication devices have become commonplace. Mobile devices have high storage capacity for digital audio, and smartphones or networked PDAs can be used to stream ...

  19. Dimensioning of communication links for base-station and MSC interconnection in CDMA mobile communication systems

    Microsoft Academic Search

    Khaled M. F. Elsayed

    1997-01-01

    In CDMA mobile communication systems, voice is encoded and packaged in variable length packets that are transported between the mobile station and the switching center. While the packetization provides great flexibility in resource allocation, it poses a QOS challenge on voice. We discuss link dimensioning for a typical CDMA system. We consider a communication link connecting a CDMA base-station and

  20. Mobile ad hoc networks for oceanic aircraft communications

    E-print Network

    Kingsbury, Ryan W

    2009-01-01

    Research into mobile ad hoc networks (MANET's) has exploded in recent years. MANET's are a type of wireless network in which independently mobile nodes are capable of self-forming and maintaining a connected network, even ...

  1. Near Field Communication and Bluetooth Bridge System for Mobile Commerce

    Microsoft Academic Search

    C. Y. Leong; K. C. Ong; K. K. Tan; O. P. Gan

    2006-01-01

    This paper presents an innovation of a Near Field Communication (NFC) and Bluetooth bridge system for connecting Bluetooth enabled mobile devices to NFC enabled consumer services. Nowadays, there is an abundance of mobile phones and PDAs with Bluetooth capability in the consumer market but there are fewer devices with NFC capability. In order for NFC enabled consumer services and payment

  2. Why young consumers are not open to mobile marketing communication

    Microsoft Academic Search

    Ian Grant

    2007-01-01

    This paper explores young people's motivations for using mobile phones. Older adoles- cents' everyday use of traditional and new forms of mediated communication were explored in the context of their everyday lives, with data generated from self-completion questionnaires, diaries and mini focus groups. The findings confirm the universal appeal of mobile phones to a youth audience. Social and entertainment-related motivations

  3. A Secure Authentication Infrastructure for Mobile Communication Services

    E-print Network

    von Bochmann, Gregor

    A Secure Authentication Infrastructure for Mobile Communication Services over the Internet Thesis everywhere, with various types of terminals, possibly mobile. In this thesis, we propose to secure for their cooperation and friendship. I think I should specially mention Khalil El-Khatib and Ronggong Song

  4. Cooperation without (reliable) communication: Interfaces for mobile applications

    Microsoft Academic Search

    Alan J. Dix

    1995-01-01

    The design of effective collaborative applications on mobile platforms has many problems. Wireless networks are fast enough that one aspires to true interactive applications, but too slow for much real-time feedback. This is exacerbated by the variability due to interference and broken connections. Mobile computing using wireless communications thus sits in a grey area between different styles of interaction. This

  5. Symbol grounding in communicative mobile robots IKAT / Infonomics -Universiteit Maastricht

    E-print Network

    Vogt, Paul

    a workable definition of a symbol. The implemented model is explained in the section called `language gamesSymbol grounding in communicative mobile robots Paul Vogt IKAT / Infonomics - Universiteit on an experiment in which two mobile robots solve the symbol grounding problem in a particular experimental setup

  6. Performance of CDMA mobile communication systems using antenna arrays

    Microsoft Academic Search

    Bruno Suard; Ayman F. Naguib; Guanghan Xu; Arogyaswami Paulraj

    1993-01-01

    The use antenna arrays in cellular code division multiple access mobile communications is studied. Techniques to localize each mobile within the cell and to generate tracking adaptive receive (and transmit) beams are addressed. The authors show that such enhancement of the CDMA system results in increased system capacity and improved robustness to power control errors. Preliminary simulation results are presented

  7. A secure network to connect (mobile) devices for interpersonal communication

    E-print Network

    Biagioni, Edoardo S.

    AllNet A secure network to connect (mobile) devices for interpersonal communication without Very little resources needed for text 140 characters for twitter, SMS A p2p network can support not secure PGP more effective if key exchange is improved Mobile devices in range of each other can

  8. An advanced system design for future global mobile satellite communications

    Microsoft Academic Search

    Hideo Okinaka; Yasuo Hirata

    1986-01-01

    This paper presents a system concept applicable to the future global mobile satellite communications system. The main features of the proposed system are a demand-assigned beam-hopping TDMA operation in the satellite-to-mobile direction and a demand-assigned SCPC operation in the mobile-to-satellite direction. A beam-hopping repeater configuration which does not require a dynamic switch between transmitters and a multiple spot beam antenna

  9. Evolving mobile communication practices of Irish teenagers

    Microsoft Academic Search

    Anthony Cawley; Deirdre Hynes

    2010-01-01

    Purpose – The purpose of this paper is to examine the social adoption of the mobile phone by Irish teenagers in city, town and rural settings. It aims to investigate two key areas that have influenced the teenagers' social adoption of the mobile phone: first, the influence of locational and socio-economic factors on mobile phone usage; second, how the teenagers'

  10. Frontiers of Wireless and Mobile Communications

    E-print Network

    Mandayam, Narayan

    applications as they migrate to mobile Internet platforms. KEYWORDS | Ad hoc and mesh networks; audiovisual Internet.[ The mobile Internet represents the second wave of the wireless revolution which started because of the popularity of Internet applications on mass-market mobile platforms including smart phones

  11. Efficient Perfectly Reliable and Secure Communication Tolerating Mobile Adversary

    E-print Network

    reliable communication from S to R tolerating a mobile adversary with arbitrary roaming speed3 . We show in the network. 3 By roaming speed we mean the speed with which the adversary changes the set of corrupted node 1" to each other via an underlying communication network that they do not trust. Note that if S and R

  12. Traffic Theory Approach for Heterogeneous Mobile Communication Networks

    Microsoft Academic Search

    Stephan Goebbels

    2007-01-01

    This paper presents a new traffic theory based approach for the analysis of heterogeneous wireless communication networks. While traffic theory is widely spread for the analysis of wired networks like the Internet the adaptation of these methods for wireless and especially heterogeneous networks is not yet accomplished. New upcoming mobile communication networks will be ruled by continuously switching radio access

  13. Quality Management using RFID and Third Generation Mobile Communications Systems

    Microsoft Academic Search

    Ng Hon; Wilton Fok; Edward Wong; Zongwei Luo

    2006-01-01

    Quality management, radio frequency identification (RFID) and third generation mobile communications systems (3G) are increasing attracting the attention of corporate managers. This paper illustrates the convergence of the three seemingly independent initiatives. RFID provides data inputs into the company's quality improvement systems, such as Six Sigma, while 3G supports realtime data communications between remote RFID devices and enterprise applications. RFID

  14. Communication-aware surveillance in mobile sensor networks

    Microsoft Academic Search

    Alireza Ghaffarkhah; Yasamin Mostofi

    2011-01-01

    In this paper, we consider a surveillance problem, where a number of mobile nodes are tasked with surveying an area for the possible presence of stationary targets and reporting their findings back to a fixed base station, in the pres- ence of realistic fading communication channels. We develop a mathematical framework for robust communication-aware surveillance, in order to survey the

  15. Advanced mobile satellite communications system using Ka and MM-wave bands in Japan's R and D satellite project

    NASA Technical Reports Server (NTRS)

    Isobe, Shunkichi; Ohmori, Shingo; Hamamoto, Naokazu; Yamamoto, Minoru

    1991-01-01

    Communications Research Laboratory (CRL) studied an advanced mobile satellite communications system using Ka and millimeter-wave bands in the R&D Satellite project. The project started in 1990 and the satellite will be launched in 1997. On-board multi-beam interconnecting is one of basic functions to realize one-hop connection among Very Small Aperture Terminals (VSATs), mobile, and hand-held terminals in future mobile satellite communications system. An Intermediate Frequency (IF) filter bank and regenerative transponder are suitable for this function. The transponder configuration of an advanced mobile communications mission of the R&D Satellite for experiment is shown. High power transmitters of Ka and millimeter-wave bands, a 3x3 IF filter band and Single Channel Per Carrier/Time Division Multiplexing (SCPC/TDM) regenerative MODEMS, which will be boarded on the R&D Satellite, are being developed for the purpose of studying the feasibility of advanced mobile communications system.

  16. Land mobile communications satellite mission (LAMOCOSAMIS) Task 1: Market study

    NASA Astrophysics Data System (ADS)

    1985-12-01

    Land mobile communication service demand in Europe and the Mediterranean basin in the years 1995-2005 was estimated. A traffic model was derived. There is an exploding demand for land mobile communications in Europe, with overwhelming preference for two way telephone services. The users survey shows a surprising lack of sensitivity to prices and tariffs, which widely contributed to the preeminence of the needs for telephone services. This demand justifies that every effort be made to develop as fast as possible a compatible pan-European terrestrial mobile system. If a large proportion of the needs may be satisfied by terrestrial mobile system solutions, the potential remaining needs for telephony, outside of the presently planned terrestrial mobile, which can be served only by satellite, even under the pessimistic economic scenario and high cost/tariff assumptions, requires a number of equivalent telephone circuits which cannot be achieved with available state of the art technology.

  17. INTRODUCTION Future mobile communication systems will con-

    E-print Network

    will be cross-linked abundantly and provide a wider range of market. On one hand, with the usage of advanced developed with increasing spectrum band and data rate. On the other hand, future mobile networks are also- tecture and new technologies, such as mobility load balancing (MLB), for LTE networks [1, 2]. Driven

  18. Mobility Research and Production Sciences

    E-print Network

    . Robert Fischer, Vice President Engineering and Technology, Powertrain Engineering AVL Matthias H. Koch. Koch, Siemens Mobility Graz 17.40 uhr Impulsreferat ,,die rolle des Verbrennungsmotors für die

  19. Communicating Mobile Nano-Machines and Their Computational Power

    NASA Astrophysics Data System (ADS)

    Wiedermann, Ji?í; Petr?, Lukáš

    A computational model of molecularly communicating mobile nanomachines is defined. Nanomachines are modeled by a variant of finite-state automata—so-called timed probabilistic automata—augmented by a severely restricted communication mechanism capturing the main features of molecular communication. We show that for molecular communication among such motile machines an asynchronous stochastic protocol originally designed for wireless (radio) communication in so-called amorphous computers with static computational units can also be used. We design an algorithm that using the previous protocol, randomness and timing delays selects with a high probability a leader from among sets of anonymous candidates. This enables a probabilistic simulation of one of the simplest known model of a programmable computer—so-called counter automaton—proving that networks of mobile nanomachines possess universal computing power.

  20. Mobile satellite communications systems: Toward global personal communications

    Microsoft Academic Search

    John H. Lodge

    1991-01-01

    The constraints imposed by the RF environment are reviewed. An overview of present and planned mobile satellite systems is given. Present systems refer to those already in operation, while planned systems refer to those that have authority to offer the services and have either a satellite in orbit or one being built to support the systems. Future directions for mobile

  1. Communication of socioeconomic research findings.

    PubMed

    Milne, R J

    1999-01-01

    Socioeconomics is research that identifies, measures and compares the costs and the clinical, economic and humanistic consequences of diseases and healthcare interventions. Research findings must be communicated to be valuable. Publication moves research findings into the public domain and exposes hard won ideas to critical appraisal. The analyst or researcher informs the decision process by defining an answerable question, applying standard economic methodology, developing a credible study, and using appropriate analytical and communication tools. The decision-maker is more likely to listen if the message is relevant, clear, simple and timely, and if he/she has influence over the relevant budget. Traditional print media provide a standardised process for quality control, whereas electronic media can provide speed of publication and wide access, usually at the expense of quality. The quality of both published medical and socioeconomic research articles varies widely. Published checklists can greatly assist in determining the structural quality of a study, but they cannot guarantee that the content of an article is useful to a decision-maker. Barriers to communication include perceived lack of study credibility, lack of relevance to the decision under consideration, suspicion of bias and inadequate training of the readers. Journal editors aim to improve the readability and clarity of articles and to bring them into conformance with journal policies. Recommendations for effective communication include the following: determine the target audience(s) and develop the appropriate perspective; set the study in its clinical context; keep the language simple where possible and use multiple communication media. Well conducted and well communicated studies can influence policy and outcomes. PMID:10623379

  2. Mobile health-monitoring system through visible light communication.

    PubMed

    Tan, Yee-Yong; Chung, Wan-Young

    2014-01-01

    Promising development in the light emitting diode (LED) technology has spurred the interest to adapt LED for both illumination and data transmission. This has fostered the growth of interest in visible light communication (VLC), with on-going research to utilize VLC in various applications. This paper presents a mobile-health monitoring system, where healthcare information such as biomedical signals and patient information are transmitted via the LED lighting. A small and portable receiver module is designed and developed to be attached to the mobile device, providing a seamless monitoring environment. Three different healthcare information including ECG, PPG signals and HL7 text information is transmitted simultaneously, using a single channel VLC. This allows for a more precise and accurate monitoring and diagnosis. The data packet size is carefully designed, to transmit information in a minimal packet error rate. A comprehensive monitoring application is designed and developed through the use of a tablet computer in our study. Monitoring and evaluation such as heart rate and arterial blood pressure measurement can be performed concurrently. Real-time monitoring is demonstrated through experiment, where non-hazardous transmission method can be implemented alongside a portable device for better and safer healthcare service. PMID:25227066

  3. Research in communication education: Directional needs

    Microsoft Academic Search

    Kathleen M. Galvin; Pamela J. Cooper

    1981-01-01

    Future Research in communication education should concentrate on (1) identifying and applying the communication functions necessary for one to participate successfully in interpersonal contexts, (2) examining communication in different learning environments, and (3) improving teacher competencies

  4. Near Field Communication Technology: Contactless Applications in Mobile Environment

    Microsoft Academic Search

    Balázs Benyó

    StoLPaN, a pan-European consortium of companies, universities and user groups co-funded by the European Commission (EU), Information Society Technologies (IST) Programme aims to define open commercial and technical frameworks for the remote management of NFC-enabled (NFC: Near Field Communication) services on mobile devices. These frameworks will facilitate the deployment of NFC-enabled mobile applications across a wide range of vertical markets,

  5. High-speed satellite mobile communications: technologies and challenges

    Microsoft Academic Search

    MOHAMED IBNKAHLA; QUAZI MEHBUBAR RAHMAN; AHMED IYANDA SULYMAN; HISHAM ABDULHUSSEIN AL-ASADY; Jun Yuan; AHMED SAFWAT

    2004-01-01

    Central features of future 4G mobile communication systems are high-speed data transmission (up to 1 Gb\\/s) and interactive multimedia services. For effective delivery of these services, the network must satisfy some stringent QoS metrics, defined typically in terms of maximum delay and\\/or minimum throughput. Mobile satellite systems will be fully integrated with the terrestrial cellular systems to provide ubiquitous global

  6. Convergence of Mobile Communications and Broadcasting: A long term perspective

    Microsoft Academic Search

    Friedrich K. Jondral; Dennis Burgkhardt; Jens Elsner; Arnold Picot; Nico Grove

    Terrestrial unidirectional broadcasting is currently being substituted by wired bidirectional IP-based services. In practical day-to-day use, user mobility for the 'last mile' is supported by wireless local area networks with massively growing data rates. Terrestrial bidirectional mobile communications, on the other hand, is currently moving into its fourth technological generation. With the new UMTS Long Term Evolution (LTE) standards, data

  7. Reliable communication for mobile MANET-WSN scenarios

    Microsoft Academic Search

    Giuseppe Cardone; Antonio Corradi; Luca Foschini

    2011-01-01

    Advances in wireless communications have motivated the development of Wireless Sensor Networks (WSNs) for low-cost and easy-deployable physical and environmental monitoring. At the same time, the evolution of portable mobile devices is enabling novel fully integrated inter- network computing scenarios by making viable to opportunistically exploit Mobile Ad-hoc NETwork (MANET) devices traversing the WSN and equipped with a WSN radio

  8. Mobile small aperture satellite terminals for military communications

    Microsoft Academic Search

    Vijitha Weerackody; Lino Gonzalez

    2007-01-01

    The United States Army is currently developing a satellite-based network-centric waveform. Mobile terminals that are small and compact are highly desirable for the military. This article gives an overview of the technical challenges and performance issues when mobile small aperture satellite terminals are connected to a network- centric communication system. The specific issues addressed are regulatory limits on off-axis emissions,

  9. Biological aspects of mobile communication fields

    Microsoft Academic Search

    James C. Lin

    1997-01-01

    Our knowledge on the biological effects of RF radiation has been increasing for many decades. It has become a focus of attention because of the accelerated use of RF radiation for wireless communication over the past few years. It is fairly well established that at sufficiently high power levels, RF and microwave energy can produce deleterious biological effects. Wireless communication

  10. EHF satellite communication systems for mobile users

    Microsoft Academic Search

    R. E. Eaves

    1979-01-01

    The large amounts of spectrum available in the EHF and upper SHF region offer the potential to provide secure satellite communications to large numbers of users. However, the cost-effective realization of this potential requires the development of satellite communication system architectures which will serve small and relatively inexpensive terminals. Conventional transponder systems are inadequate both in the security they provide

  11. Mobility Support in Real-time Video Communication UUUU

    Microsoft Academic Search

    Thomas C. Schmidt; Matthias Wählisch; Hans L. Cycon; Mark Palkow

    2003-01-01

    Mobile Internet devices recently gained much popu- larity and became widely available. Following an 802.11a\\/b or 3G standard they provide enough bandwidth to support data intensive communication services such as videoconferencing. Facing the emerging paradigm of ubiquitous computing and communication voice and videoconferencing over IP are on the spot to establish as standard Internet solutions. However, heavy infrastructural burdens and

  12. WIRELESS COMMUNICATIONS MOBILE COMPUTING Wirel. Commun. Comput. 10.1002/wcm.1)

    E-print Network

    Giannakis, Georgios

    parameters instrumental in virtually aspects mobile communication system design. example, handoff initiationWIRELESS COMMUNICATIONS MOBILE COMPUTING Wirel. Commun. Comput. 10.1002/wcm.1) REVIEW Estima tion handoff algorithms and optimal tuning system parameters changing channel conditions adaptive transmission

  13. A PCM-TDMA one dimensional mobile communication system using leaky coaxial cables

    Microsoft Academic Search

    Shoichiro Sakata; Tadao Saito; Hiroshi Inose

    1984-01-01

    In TDMA mobile communication systems, synchronization between a base station and mobile stations is a primary problem. This paper proposes a new mobile station synchronization scheme which does not require the propagation delay measurement or very long guard time for a one-dimensional mobile communication system using leaky coaxial cables (LCX). It shows that a large-capacity PCM-TDA mobile communication system can

  14. A satellite system for land-mobile communications in Europe

    NASA Astrophysics Data System (ADS)

    Bartholome, P.; Rogard, R.

    1988-05-01

    There exists a great unsatisified demand for land mobile communications in Europe, particularly in sectors of business activity such as the road transport industry. This demand could best be satisfied by means of satellite-based private networks providing voice and data communications in a hub configuration. The potential market is estimated to encompass several hundred thousand road vehicles and the transmission capacity required would be several thousand channels. ESA is currently demonstrating the potential of satellite communications for this type of application, using a system called PRODAT. System studies are being performed with the aim of defining the architecture of a regional satellite system for Europe.

  15. Global Mobility Management by Replicated Databases in Personal Communication Networks*

    E-print Network

    Leung, Kin K.

    [GPM92] has been established as an industry standard in the Global System for Mobile Telecommunication with industry protocol standards - and compare them with the traditional, centralized database scheme telecommunication services, such as Personal Communication and Software Defined Network (SDN) services, today

  16. Wireless Data Communication, Fall 03 Lecture 2. IP Mobility Support

    E-print Network

    Schwefel, Hans-Peter

    Wireless Data Communication, Fall 03 Lecture 2. IP Mobility Support Exercises 1. MIP Performance header bytes for Layer 3 and higher. The CN and the MH establish a bi-directional VoIP session (via UDP/IP network (assuming IP in IP tunneling)? o How does the latter change if minimal encapsulation is used

  17. Automated troubleshooting of a mobile communication network using Bayesian networks

    Microsoft Academic Search

    R. Barco; L. Nielsen; R. Guerrero; G. Hylander; S. Patel

    2002-01-01

    Operators of mobile communication networks face the challenging task of maintaining a complex network with thousands of cells. It requires highly skilled troubleshooting engineers to avoid a situation where subscribers are not properly served. This paper presents a new method for automating the troubleshooting task, thereby freeing a large portion of resources for other purposes. The method is described in

  18. Context-based remote security control for Mobile Communication Device

    Microsoft Academic Search

    Gaeil An; Daehee Seo; Jonghyun Kim; Kiyoung Kim; Dongil Seo

    2010-01-01

    Recently, as smartphone is becoming more and more popular, concern about security threats against Mobile Communication Device (MCD) is getting higher. The MCD can not only become the target of the cyber attacks, but also be used as the tool of the cyber attacks. This paper proposes a context-based remote security control scheme for MCD. The proposed scheme consists of

  19. Characteristics of early adopters in mobile communications markets

    Microsoft Academic Search

    Juha Munnukka

    2007-01-01

    Purpose – The purpose of this paper is to study consumers' adoption of mobile communications services, and to explore common denominators uniting those most likely to be early adopters; thereby, to help practitioners to predict early adoption and segment the market. Design\\/methodology\\/approach – Data were collected by postal questionnaire from 26 per cent of a sample of 3,000 customers of

  20. RF microelectronics for W-CDMA mobile communication systems

    Microsoft Academic Search

    A. Springer; R. Weigel

    2002-01-01

    Third generation (3G) mobile communication systems are now just at the beginning of their introduction. With a maximum data rate of 2 Mbps they will make wireless access to broadband data services like Internet or video applications feasible. Most of the different physical layer technologies summarized under the acronym 3G are based on Wideband - CDMA (W-CDMA) which is in

  1. Kalman filtering for power estimation in mobile communications

    Microsoft Academic Search

    Tao Jiang; Nicholas D. Sidiropoulos; Georgios B. Giannakis

    2003-01-01

    In wireless cellular communications, accurate local mean (shadow) power estimation performed at a mobile station is important for use in power control, handoff, and adaptive transmission. Window-based weighted sample average shadow power estimators are commonly used due to their simplicity. In practice, the performance of these estimators degrades severely when the window size deviates beyond a certain range. The optimal

  2. Channel-Individual Adaptive Beamforming for Mobile Satellite Communications

    Microsoft Academic Search

    Thomas Gebauer; Heinz G. Göckler

    1995-01-01

    A digital frequency-division multiplex demultiplexer for single channel per carrier (SCPC) signals was developed for use in a digital channel-individual beamforming network for an adaptive satellite array antenna for mobile satellite communications. The available ASIC (35000 gate functions in CMOS technology, clock rate up to 30 MHz with low power consumption) permits the separation of FDM signals comprising up to

  3. Multiservice on-board switching for mobile satellite communications

    Microsoft Academic Search

    L. Bella

    1988-01-01

    Future satellites for mobile communications will be required to interface ground ISDN (integrated services digital network) and to provide services and performances comparable with those offered by cellular radio networks. Onboard processing is a key technique to satisfy these requirements and can provide efficient integration with fixed satellite services. The European Space Agency (ESA) has started the development of a

  4. Using Mobile Communications to Assert Privacy from Video Surveillance

    Microsoft Academic Search

    Jack Brassil

    2005-01-01

    We propose a novel use of mobile communications to permit individuals to assert a preference for privacy from video surveillance. Our system, called Cloak, grants an individual the right to prohibit others from distributing video containing their image. We present our system architecture and operation, and demonstrate how the system enhances privacy while requiring no change to existing surveillance technology.

  5. Mobile communications system simulator development using structured analysis

    Microsoft Academic Search

    Jarno M. A. Tanskanen; Matti J. Rintamäki

    2001-01-01

    In this paper, structured analysis (SA) is employed in mobile communications system simulation software development. Programming via SA provides a well-defined and easily maintainable structure for the software in a graphical form, also revealing any hidden dependencies in the software. Thus, the resulting simulator is more reliable and maintainable over its whole lifecycle. With modern SA tools, documentation can be

  6. Model-based Security Analysis for Mobile Communications

    E-print Network

    Jurjens, Jan

    and use cases Abuse frames Security requirements Risk analysis External review Design Test plans Code Test results Field feedback Risk-based Security tests Static analysis (tools) Risk analysis Penetration testingModel-based Security Analysis for Mobile Communications Jan Jürjens1 , Jörg Schreck2 , Peter

  7. Accountable Anonymous Service Usage in Mobile Communication Systems \\Lambda

    E-print Network

    Bencsáth, Boldizsár

    Accountable Anonymous Service Usage in Mobile Communication Systems \\Lambda Levente Butty Abstract We introduce a model that allows of anonymous yet accountable service usage in mo­ bile revocable anonymity for users, which means that the identity of misbehaving users can be revealed. 1

  8. QoS management for the next mobile communication network

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Lu, Jun; Yu, Jianwei; He, Feng

    2004-04-01

    With convergence of network technologies, future network infrastructure will be based on IP and traditional wireless/mobile networks will also evolve inevitably to a unified all-IP mobile internet which can support voice, data and video simultaneously. But, the pattern served by IP is best effort. So IP mobility and QoS management have been the main challenges of all-IP mobile networks. Based on Mobile IP, IP QoS protocol, etc, ... The paper brings forward an end-to-end QoS management solution for the next mobile communication network, introduces a terminology of QoS Agent Server (QAS), which acts as resource manage server and participate in dynamic Service Level Specification (SLS) negotiation with mobile hosts (MH) or other QAS. Taking advantage of the mechanisms, discussed the process of QoS manage to support mobile hosts' fast handoff between cells. Additionally, adopted and self-adaptive control algorithm for non-real time service on interior nodes. Finally, conclusions are given and possible future works are described.

  9. Land-mobile satellite communication system

    NASA Technical Reports Server (NTRS)

    Yan, Tsun-Yee (Inventor); Rafferty, William (Inventor); Dessouky, Khaled I. (Inventor); Wang, Charles C. (Inventor); Cheng, Unjeng (Inventor)

    1993-01-01

    A satellite communications system includes an orbiting communications satellite for relaying communications to and from a plurality of ground stations, and a network management center for making connections via the satellite between the ground stations in response to connection requests received via the satellite from the ground stations, the network management center being configured to provide both open-end service and closed-end service. The network management center of one embodiment is configured to provides both types of service according to a predefined channel access protocol that enables the ground stations to request the type of service desired. The channel access protocol may be configured to adaptively allocate channels to open-end service and closed-end service according to changes in the traffic pattern and include a free-access tree algorithm that coordinates collision resolution among the ground stations.

  10. Coherent versus noncoherent signaling for satellite-aided mobile communications

    NASA Technical Reports Server (NTRS)

    Davarian, F.; Sumida, J.

    1986-01-01

    The use of coherent versus noncoherent communications is an unresolved issue for the mobile satellite community. Should one select the more robust but less efficient noncoherent strategy for communications over satellite-aided mobile channels, or does the introduction of a space platform in the mobile link improve signal stability (both amplitude and phase) such that conventional coherent schemes become attractive? This publication tries to answer some of the questions by discussing the results from experiments using a coherent QPSK receiver. The issues discussed include items such as the measured performance in Rician fading, the link error floor in a fading environment, etc. The results are compared and contrasted with that of a noncoherent limiter/discriminator FM receiver.

  11. Remote identification and information processing with a near field communication compatible mobile phone

    Microsoft Academic Search

    Raine Kelkka; Tommi Kallonen; Jouni Ikonen

    2009-01-01

    Mobile phones have become a popular platform for diverse applications in different fields. Near Field Communication (NFC), short range contactless communication standard developed especially for end user devices, is one the most novel technologies integrated into mobile phones. This paper presents a scenario where a Near Field Communication enabled mobile phone is used to identify a construction element, display information

  12. Exploring the Concept of Mobile Viral Marketing through Case Study Research

    Microsoft Academic Search

    Dietmar G. Wiedemann

    2007-01-01

    Mobile viral marketing has a tremendous potential for communication and distribution purposes. Although seen as an important issue from the viewpoint of practitioners there has been little research on the phenomenon so far. This paper represents a first step in filling this void. We examine 34 case studies in order to identify relevant characteristics of mobile viral marketing. The outcome

  13. Integrating Communication, Computer Access, Environmental Control & Mobility.

    ERIC Educational Resources Information Center

    Romich, Barry A.; Vagnini, Carol B.

    Severely physically disabled people can be helped to reach their goals in educational, vocational, and personal pursuits through appropriate use of current technology. The expressive communication needs of people without functional speech can be met through an analysis of selection techniques, processing, and outputs. Examples of new systems…

  14. Analysis of a mobile communication security protocol

    Microsoft Academic Search

    Tom Coffey; Reiner Dojen

    2003-01-01

    Cryptographic protocols are used to achieve secure communication over insecure networks. Weaknesses in such protocols are hard to identify, as they can be the result of subtle design flaws. Formal verification techniques provide rigid and thorough means to evaluate security protocols. This paper demonstrates the process of formal verification by applying a logic to a security protocol intended for use

  15. Political Communication Research in the 1980s.

    ERIC Educational Resources Information Center

    Meadow, Robert G.

    1985-01-01

    Discusses eight books, including a textbook for undergraduates, that represent the type of research being conducted in the political communication field. Identifies major problems of current research. (PD)

  16. Payload system tradeoffs for mobile communications satellites

    NASA Technical Reports Server (NTRS)

    Moody, H. J.

    1990-01-01

    System level trade-offs carried out during Mobile Satellite (M-SAT) design activities are described. These trade-offs relate to the use of low level beam forming, flexible power and spectrum distribution, and selection of the number of beams to cover the service area. It is shown that antenna performance can be improved by sharing horns between beams using a low level beam forming network (BFN). Additionally, greatly increased power utilization is possible using a hybrid matrix concept to share power between beams.

  17. The Globalstar mobile satellite system for worldwide personal communications

    NASA Astrophysics Data System (ADS)

    Wiedeman, Robert A.; Viterbi, Andrew J.

    Loral Aerospace Corporation along with Qualcomm Inc. have developed a satellite system which offers global mobile voice and data services to and from handheld and mobile user terminals with omni-directional antennas. By combining the use of low-earth orbit (LEO) satellites with existing terrestrial communications systems and innovative, highly efficient spread spectrum techniques, the Globalstar system provides users with low-cost, reliable communications throughout the world. The Globalstar space segment consists of a constellation of 48 LEO satellites in circular orbits with 750 NM (1389 km) altitude. Each satellite communicates with the mobile users via the satellite-user links and with gateway stations. The gateway stations handle the interface between the Globalstar network and the OSTN/PLMN systems. Globalstar transceivers are similar to currently proposed digital cellular telephones in size and have a serial number that will allow the end user to make and receive calls from or to that device anywhere in the world. The Globalstar system is designed to operate as a complement to existing local, long-distance, public, private and specialized telecommunications networks. Service is primarily designed to serve the rural and thin route communications needs of consumers, government users, and private networks.

  18. Communicating Research to Small Drinking Water Systems: Dissemination by Researchers

    EPA Science Inventory

    This talk discusses the challenges of disseminating research relevant to small systems. The presentation discusses efforts by the U.S. EPA’s Office of Research and Development to effectively communicating drinking water information. In particular, communication approaches ...

  19. Communication Research and the Study of Surveillance

    Microsoft Academic Search

    Kelly Gates; Shoshana Magnet

    2007-01-01

    This paper outlines some of the productive points of intersection between communications research and the study of surveillance. It highlights some of the contributions that the field of communications has made to the emerging interdisciplinary field of surveillance studies, and suggests some possible lines of research in the areas of consumer surveillance and interactive media, police communications and surveillance, closed-circuit

  20. A Center for Research in Scientific Communication.

    ERIC Educational Resources Information Center

    Schuelke, L. David; And Others

    The objectives of the Center for Research in Scientific Communication at the University of Minnesota, Saint Paul, are to assist scientists in short-term communication projects; to produce, through research, new knowledge in the area of scientific communicaton; and to provide regular, systematic, and experimental analysis of communication variables…

  1. Man-Machine Communication Research: Final Report.

    ERIC Educational Resources Information Center

    Mann, William C.

    The general goal of this research and development program was to facilitate man-machine communication in areas of high military impact, including on-line computing in communications, command, and control. Highlights of this research include: identification of major causes of man-machine communication difficulty for the computer-naive; discovery of…

  2. Research Supporting Satellite Communications Technology

    NASA Technical Reports Server (NTRS)

    Horan Stephen; Lyman, Raphael

    2005-01-01

    This report describes the second year of research effort under the grant Research Supporting Satellite Communications Technology. The research program consists of two major projects: Fault Tolerant Link Establishment and the design of an Auto-Configurable Receiver. The Fault Tolerant Link Establishment protocol is being developed to assist the designers of satellite clusters to manage the inter-satellite communications. During this second year, the basic protocol design was validated with an extensive testing program. After this testing was completed, a channel error model was added to the protocol to permit the effects of channel errors to be measured. This error generation was used to test the effects of channel errors on Heartbeat and Token message passing. The C-language source code for the protocol modules was delivered to Goddard Space Flight Center for integration with the GSFC testbed. The need for a receiver autoconfiguration capability arises when a satellite-to-ground transmission is interrupted due to an unexpected event, the satellite transponder may reset to an unknown state and begin transmitting in a new mode. During Year 2, we completed testing of these algorithms when noise-induced bit errors were introduced. We also developed and tested an algorithm for estimating the data rate, assuming an NRZ-formatted signal corrupted with additive white Gaussian noise, and we took initial steps in integrating both algorithms into the SDR test bed at GSFC.

  3. Compact mobile terminals for multi-beam mobile satellite communication systems

    NASA Astrophysics Data System (ADS)

    Sakai, Tsutomu; Komagata, Hitoshi; Terada, Noriyoshi; Hagiwara, Eiji

    Two types of compact mobile terminals for multibeam mobile satellite communications systems are described. One of them is designed for telephone service with 8-kb/s or 16-kb/s APC-AB (adaptive predictive coding-asynchronous binary) codecs or corresponding nontelephone services, such as facsimile; the other is for low-speed message service. For the 8-kb/s or 16-kb/s mobile terminal, an electronically steerable switched antenna technique, a digital signal processing technique, and custom LSIs are adopted to reduce equipment size. This terminal can be mounted on a small vessel or vehicle. For the message terminal, an omnidirectional antenna with a conically shaped radiation pattern is used, and its portability allows easy and instant communications anywhere at any time.

  4. Near field communication: getting in touch with mobile users.

    PubMed

    Hoy, Matthew B

    2013-01-01

    Near field communication is a method for sending and receiving small amounts of data across very short distances wirelessly. This technology is already available in a number of mobile devices and has many possible uses, including electronic payment, access control, and information exchange. This article will explain the basic principles of near field communication, discuss some of the ways it can be used in libraries, and explore some possible concerns with the technology. A list of resources for additional information is also included. PMID:23869639

  5. The design of static and mobile HF communication systems

    NASA Astrophysics Data System (ADS)

    Darnell, M.

    1986-03-01

    The lecture deals with more specific aspects of HF communication system design arising from a previous lecture entitled HF system design principles presented as part of AGARD Lecture Series 127 in 1983. The major topics considered are: (1) the design of point-to-point systems; (2) the design of systems involving mobile terminals; (3) system control and frequency management; (4) resistance to interception and disruption. The lecture is intended to provide a technical framework for later lectures covering the more detailed aspects of HF communication system design.

  6. Silicon integration of digital user-end mobile communication systems

    Microsoft Academic Search

    L. Philips; I. Bolsens; A. Rabaeijs; B. Vanhoof; J. Vanhoof; H. De Man

    1993-01-01

    An approach to single-chip integration of digital user-end mobile communication systems is presented. The characteristics of this class of DSP (digital signal processing) systems define the requirements of the proposed system architecture and system design environment. A distributed control approach has been chosen. The system design environment provides high-level system synthesis towards mixed architectural styles and silicon assembly in mixed

  7. Rayleigh fading compensation for QAM in land mobile radio communications

    Microsoft Academic Search

    Seiichi Sampei; Terumi Sunaga

    1993-01-01

    A pilot symbol-aided Rayleigh fading compensation is investigated for M-ary quadrature amplitude modulation (QAM) to achieve highly spectrally efficient land mobile communication systems. The optimum parameters for fading compensation, bit error rate (BER) performance against Eb\\/N0 (energy per bit to the noise power spectrum density), adjacent channel interference, and cochannel interference for 16-QAM, 64-QAM, and 256-QAM, and the spectral efficiencies

  8. Interference cancelling equalizer (ICE) for mobile radio communication

    Microsoft Academic Search

    Hitoshi Yoshino; Kazuhiko Fukawa; H. Sukuki

    1997-01-01

    This paper proposes an adaptive interference cancelling equalizer (ICE), which not only equalizes intersymbol interference (ISI), but also cancels cochannel interference (CCI) in the received signal in Rayleigh-fading environments, ICE is an adaptive multiuser detector for the frequency-selective fading environment commonly experienced by mobile communication channels. ICE employs a novel detection scheme: recursive least-squares maximum-likelihood sequence estimation (RLS-MLSE), which simultaneously

  9. Energy conservation in access protocols for mobile computing and communication

    Microsoft Academic Search

    I. Chlamtac; C. Petrioli; J. Redi

    1998-01-01

    Accelerating consumer interest and mushrooming applications for portable networked devices are driving the demand for the optimization of their functions and components. Porta-bility also necessitates reliance on small, self-contained and therefore limited-life power sources such as batteries, making power-management critical to a successful and wide-spread deployment of these new mobile devices. Meanwhile, commu-nications capabilities are fast becoming standard functions on

  10. COMMUNICATION (European Clinical Research Infrastructures Network)

    E-print Network

    Paris-Sud XI, Université de

    COMMUNICATION ECRIN (European Clinical Research Infrastructures Network) et la structuration de la recherche clinique en Europe Mots clés : Recherche biomédicale. Europe ECRIN (European Clinical Research Infrastructures Network), a pan-european infrastructure for clinical research Key-words (Index medicus

  11. A Jabber Based Framework for Building Communication Capable Java Mobile Applications

    Microsoft Academic Search

    Mohy Mahmoud; Sherif G. Aly; Ahmed Sabry; Mostafa Hamza

    2009-01-01

    The main aim of this framework and library is to provide Java Micro Edition developers a powerful mechanism that facilitates the process of building communication capable mobile applications. The framework enables mobile devices to abstractly exchange streams of data using an underlying communication infrastructure, and also supports the continued connectivity of mobile devices as they roam into different physical locations.

  12. Biocybernetic Communication Research 1967-1984.

    ERIC Educational Resources Information Center

    Malik, M. F.

    This paper introduces and explains what was being done in biocybernetic communication research at the Myer Pollack Communication Research Laboratory in Montreal (Canada) from 1967 to 1984. It also lists persons and researchers directly involved in the activities and projects of the laboratory. The paper concludes with brief descriptions of five…

  13. Research on UV scattering communication

    NASA Astrophysics Data System (ADS)

    Dong, Ke-yan; Lou, Yan; Ding, Ying; Wang, Shuo; Wang, Hongliang; Jiang, Hui-lin

    2013-08-01

    Ultraviolet (UV) scattering communication is a broadcast communication mode of information transmission by particles in the atmosphere scattering effect on the blind band ultraviolet light, there are many advantages such as unaffected by electromagnetic radiation, good confidentiality, non-line-of sight communication. This type communication mainly used in a short distance, secure communication, which was superior to no line communication in aspect of anti-jamming and secrecy. Firstly the military requirement of UV scattering communication is analyzed in this paper, The development trend is introduced, then the composition and working principle of ultraviolet scattering communication system are also discussed, The key influential factors of UV communication system path transmission loss effects on parameters such as receiver, transmitter and received beam divergence angle, pitch angle and the communication distance were analyzed. Attenuation was quantitatively simulated under different atmospheres, communication patterns and structure parameters. The results show that: transmission distance increases with increasing beam divergence angle and decreasing field angle. And the received view angle of influence on the communication distance is far greater than the emission beam divergence angle; transmission distance increases with increasing beam divergence angle and decreasing field and field angle effects on communication distance is greater than beam divergence angle.

  14. Mobile mental health: a challenging research agenda.

    PubMed

    Olff, Miranda

    2015-01-01

    The field of mobile health ("m-Health") is evolving rapidly and there is an explosive growth of psychological tools on the market. Exciting high-tech developments may identify symptoms, help individuals manage their own mental health, encourage help seeking, and provide both preventive and therapeutic interventions. This development has the potential to be an efficient cost-effective approach reducing waiting lists and serving a considerable portion of people globally ("g-Health"). However, few of the mobile applications (apps) have been rigorously evaluated. There is little information on how valid screening and assessment tools are, which of the mobile intervention apps are effective, or how well mobile apps compare to face-to-face treatments. But how feasible is rigorous scientific evaluation with the rising demands from policy makers, business partners, and users for their quick release? In this paper, developments in m-Health tools-targeting screening, assessment, prevention, and treatment-are reviewed with examples from the field of trauma and posttraumatic stress disorder. The academic challenges in developing and evaluating m-Health tools are being addressed. Evidence-based guidance is needed on appropriate research designs that may overcome some of the public and ethical challenges (e.g., equity, availability) and the market-driven wish to have mobile apps in the "App Store" yesterday rather than tomorrow. PMID:25994025

  15. Mobile mental health: a challenging research agenda

    PubMed Central

    Olff, Miranda

    2015-01-01

    The field of mobile health (“m-Health”) is evolving rapidly and there is an explosive growth of psychological tools on the market. Exciting high-tech developments may identify symptoms, help individuals manage their own mental health, encourage help seeking, and provide both preventive and therapeutic interventions. This development has the potential to be an efficient cost-effective approach reducing waiting lists and serving a considerable portion of people globally (“g-Health”). However, few of the mobile applications (apps) have been rigorously evaluated. There is little information on how valid screening and assessment tools are, which of the mobile intervention apps are effective, or how well mobile apps compare to face-to-face treatments. But how feasible is rigorous scientific evaluation with the rising demands from policy makers, business partners, and users for their quick release? In this paper, developments in m-Health tools—targeting screening, assessment, prevention, and treatment—are reviewed with examples from the field of trauma and posttraumatic stress disorder. The academic challenges in developing and evaluating m-Health tools are being addressed. Evidence-based guidance is needed on appropriate research designs that may overcome some of the public and ethical challenges (e.g., equity, availability) and the market-driven wish to have mobile apps in the “App Store” yesterday rather than tomorrow. PMID:25994025

  16. Research and Simulation on Application of the Mobile IP Network

    NASA Astrophysics Data System (ADS)

    Yibing, Deng; Wei, Hu; Minghui, Li; Feng, Gao; Junyi, Shen

    The paper analysed the mobile node, home agent, and foreign agent of mobile IP network firstly, some key technique, such as mobile IP network basical principle, protocol work principle, agent discovery, registration, and IP packet transmission, were discussed. Then a network simulation model was designed, validating the characteristic of mobile IP network, and some advantages, which were brought by mobile network, were testified. Finally, the conclusion is gained: mobile IP network could realize the expectation of consumer that they can communicate with others anywhere.

  17. The Contemporary Relevance of Communication Research: Using "Communication Currents" in the Communication Curriculum

    ERIC Educational Resources Information Center

    Waldeck, Jennifer H.

    2008-01-01

    The purpose of this report is to describe a rationale and strategies for use of the National Communication Association's online magazine, "Communication Currents", in the undergraduate communication curriculum. "Communication Currents" features essays that translate current scholarship published in NCA journals, making the research "understandable…

  18. A secure application invocation mechanism in mobile phones for Near Field Communication

    Microsoft Academic Search

    Kwanghoon Choi; Jaekwon Kim; Seog Park

    2012-01-01

    This paper proposes an access control based, secure Near Field Communication in mobile phones. We make NFC tags hold codes of which the execution can make use of mobile services securely under user defined policies.

  19. Communication networks for autonomous mobile robot computer architectures and distributed real-time computing

    NASA Astrophysics Data System (ADS)

    Aras, Caglan Mehmet

    1993-12-01

    Communication networks play an increasingly important role in many areas of computing. This dissertation introduces an interprocessor communication network for mobile robot computer architectures and real-time communication networks for distributed real-time computing. In both cases, the objective of the research is to provide communication with very low delay. Mobile robot tasks such as collision avoidance and dynamic navigation change over time and exhibit a high degree of cooperation. The segmented bus is a reconfigurable interconnection network for intelligent mobile robot applications. The segmented bus employs a preemptive circuit-switched message transfer technique for low delay. For mobile robot applications, analysis suggests that message delays are lower on the segmented bus as compared to alternatives such as the multiple bus. Interactive real-time message streams are used in continuous media distributed sensing and command/control applications. These streams require low end-to-end delay bounds and zero-loss. This dissertation offers solutions to message-stream admission and low latency message transfers for interactive real-time message streams on communication networks. The proposed adaptive stream admission procedure is shown to admit more streams to a network than previous approaches. The proposed preemphasis cut-through data transfer mechanism reduces the minimum achievable end-to-end delay bound of a packet-switched network to values approaching circuit-switched techniques. To obtain low latencies on integrated broadband networks, the asynchronous transfer mode (ATM) must support bound-delay, zero-loss data transfers. A message-level delay control mechanism based on preemptive cut-through is presented. Hardware and software to implement message-level delay control are described results show a significant reduction in computation requirements when message-level delay control is used on ATM switch processors.

  20. A high-speed railway mobile communication system based on LTE

    Microsoft Academic Search

    Gao Tingting; Sun Bin

    2010-01-01

    Along with the developments of the high-speed railway, higher and higher technical requirements for the high-speed railway mobile communication system are raised. Since the “Global System for Mobile Communications Railways” (GSM-R) implemented today is based on GSM, the new technology in GSM evolution can be used in the highspeed railway mobile communication system to adapt to the new requirements. This

  1. Research as Ideology in Professional Communication.

    ERIC Educational Resources Information Center

    Blyler, Nancy Roundy

    1995-01-01

    Claims that the debate over research in professional communication is grounded in ideology. Discusses the ideology of two research perspectives: functionalist and critical interpretive. Sets recent discussions in professional communication in a functionalist framework, then posits that a critical interpretive ideology provides an alternative.…

  2. Overview of NASA Glenn Aero/Mobile Communications Demonstrations

    NASA Technical Reports Server (NTRS)

    Brooks, David; Hoder, Doug; Wilkins, Ryan

    2004-01-01

    The Glenn Research Center at Lewis Field (GRC) has been involved with several other NASA field centers on various networking and RF communications demonstrations and experiments since 1998. These collaborative experiments investigated communications technologies new to aviation, such as wideband Ku satcom, L-band narrowband satcom, and IP (Internet Protocol), using commercial off-the-shelf (COTS) components These technologies can be used to distribute weather and hazard data, air traffic management and airline fleet management information, and passenger cabin Internet service.

  3. Overview of NASA Glenn Aero/Mobile Communication Demonstrations

    NASA Technical Reports Server (NTRS)

    Brooks, David; Hoder, Doug; Wilkins, Ryan

    2004-01-01

    The Glenn Research Center at Lewis Field (GRC) has been involved with several other NASA field centers on various networking and RF communications demonstrations and experiments since 1998. These collaborative experiments investigated communications technologies new to aviation, such as wideband Ku satcom, L-band narrowband satcom, and IP (Internet Protocol), using commercial off-the-shelf (COTS) components These technologies can be used to distribute weather and hazard data, air traffic management and airline fleet management information, and passenger cabin Internet service.

  4. Agent Based Simulation Research of Mobile Commerce Value Chain

    Microsoft Academic Search

    Qingqun Zeng; Bin Hu; Debin Zhang

    2009-01-01

    The value added process of mobile commerce value chain is studied. Technical aspect of mobile commerce has matured, however, development of any industry needs a stable and sustainable benefit pattern, thus the research of value chain could find and enforce the mobile value chain increment, besides pushing the industry forward. First, the activities of different stages in the mobile commerce

  5. Development of a mobile research flight test support capability

    NASA Technical Reports Server (NTRS)

    Rhea, Donald C.; Moore, Archie L.

    1988-01-01

    This paper presents the approach taken by the NASA Western Aeronautical Test Range (WATR) of the Ames Research Center (ARC) to develop and utilize mobile systems to satisfy unique real-time research flight test requirements of research projects such as the advanced fighter technology integration (AFTI) F-16, YAV-8B Harrier, F-18 high-alpha research vehicle (HARV), XV-15, and the UH-60 Black Hawk. The approach taken is cost-effective, staff efficient, technologically current, and provides a safe and effective research flight test environment to support a highly complex set of real-time requirements including the areas of tracking and data acquisition, communications (audio and video) and real-time processing and display, postmission processing, and command uplink. The development of this capability has been in response to the need for rapid deployment at varied site locations with full real-time comutation and display capability. This paper will discuss the requirements, implementation and growth plan for mobile systems development within the NASA Western Aeronautical Test Range.

  6. Development of a mobile research flight test support capability

    NASA Technical Reports Server (NTRS)

    Rhea, Donald C.; Moore, Archie L.

    1988-01-01

    This paper presents the approach taken by the NASA Western Aeronautical Test Range (WATR) of the Ames Research Center to develop and utilize mobile systems to satisfy unique real-time research flight test requirements of research projects such as the advanced fighter technology integration (AFTI)F-16, YAV-8B Harrier, F-18 high-alpha research vehicle (HARV), XV-15, and the UH-60 Black Hawk. The approach taken is cost-effective, staff efficient, technologically current, and provides a safe and effective research flight test environment to support a highly complex set of real-time requirements including the areas of tracking and data acquisition, communications (audio and video) and real-time processing and display, postmission processing, and command uplink. The development of this capability has been in response to the need for rapid deployment at varied site locations with full real-time computations and display capability. This paper will discuss the requirements, implementation and growth plan for mobile systems development within the NASA Western Aeronautical Test Range.

  7. Receiver synchronisation techniques for CDMA mobile radio communications based on the use of a priori information 

    E-print Network

    Vardoulias, George

    Receiver synchronisation can be a major problem in a mobile radio environment where the communication channel is subject to rapid changes. Communication in spread spectrum systems is impossible unless the received spreading ...

  8. Broadband and scalable mobile satellite communication system for future access networks

    NASA Astrophysics Data System (ADS)

    Ohata, Kohei; Kobayashi, Kiyoshi; Nakahira, Katsuya; Ueba, Masazumi

    2005-07-01

    Due to the recent market trends, NTT has begun research into next generation satellite communication systems, such as broadband and scalable mobile communication systems. One service application objective is to provide broadband Internet access for transportation systems, temporal broadband access networks and telemetries to remote areas. While these are niche markets the total amount of capacity should be significant. We set a 1-Gb/s total transmission capacity as our goal. Our key concern is the system cost, which means that the system should be unified system with diversified services and not tailored for each application. As satellites account for a large portion of the total system cost, we set the target satellite size as a small, one-ton class dry mass with a 2-kW class payload power. In addition to the payload power and weight, the mobile satellite's frequency band is extremely limited. Therefore, we need to develop innovative technologies that will reduce the weight and maximize spectrum and power efficiency. Another challenge is the need for the system to handle up to 50 dB and a wide data rate range of other applications. This paper describes the key communication system technologies; the frequency reuse strategy, multiplexing scheme, resource allocation scheme, and QoS management algorithm to ensure excellent spectrum efficiency and support a variety of services and quality requirements in the mobile environment.

  9. Anonymous Authentication Protocols with Credit-Based Chargeability and Fair Privacy for Mobile Communications

    Microsoft Academic Search

    Chun-i Fan; Vincent Shi-ming Huang

    2007-01-01

    Smart and tiny mobile phones are widely popularized and advanced mobile communication services are provided increasingly such\\u000a that ubiquitous computing environments will come true soon. It is a pleasure for mobile users to work or get recreations in\\u000a the mobile network environments. However, just as the cases in wireline networks, there are many security threats to mobile\\u000a network systems and

  10. Radial microstrip slotline feed network for circular mobile communications array

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.; Kelly, Eron S.; Lee, Richard Q.; Taub, Susan R.

    1994-01-01

    In mobile and satellite communications there is a need for low cost and low profile antennas which have a toroidal pattern. Antennas that have been developed for mobile communications include a L-Band electronically steered stripline phased array, a Ka-Band mechanically steered elliptical reflector antenna and a Ka-Band printed dipole. In addition, a L-Band mechanically steered microstrip array, a L-Band microstrip phased array tracking antenna for mounting on a car roof and an X-Band radial line slotted waveguide antenna have been demonstrated. In the above electronically scanned printed arrays, the individual element radiates normally to the plane of the array and hence require a phase shifter to scan the beam towards the horizon. Scanning in the azimuth is by mechanical or electronic steering. An alternate approach is to mount microstrip patch radiators on the surface of a cone to achieve the required elevation angle. The array then scans in the azimuth by beam switching.

  11. Mobile marketing research: The-state-of-the-art

    Microsoft Academic Search

    Kaan Varnali; Ay?egül Toker

    2010-01-01

    Rapid proliferation in the business potential of mobile marketing attracts researchers from various fields to contribute to the growing body of knowledge on the phenomena. Although the literature on mobile marketing is accumulating, the stream of research is still in the development stage, hence is highly inconsistent and fragmented. This paper aims to organize and classify the literature on mobile

  12. Robust Timing Synchronization in Aeronautical Mobile Communication Systems

    NASA Technical Reports Server (NTRS)

    Xiong, Fu-Qin; Pinchak, Stanley

    2004-01-01

    This work details a study of robust synchronization schemes suitable for satellite to mobile aeronautical applications. A new scheme, the Modified Sliding Window Synchronizer (MSWS), is devised and compared with existing schemes, including the traditional Early-Late Gate Synchronizer (ELGS), the Gardner Zero-Crossing Detector (GZCD), and the Sliding Window Synchronizer (SWS). Performance of the synchronization schemes is evaluated by a set of metrics that indicate performance in digital communications systems. The metrics are convergence time, mean square phase error (or root mean-square phase error), lowest SNR for locking, initial frequency offset performance, midstream frequency offset performance, and system complexity. The performance of the synchronizers is evaluated by means of Matlab simulation models. A simulation platform is devised to model the satellite to mobile aeronautical channel, consisting of a Quadrature Phase Shift Keying modulator, an additive white Gaussian noise channel, and a demodulator front end. Simulation results show that the MSWS provides the most robust performance at the cost of system complexity. The GZCD provides a good tradeoff between robustness and system complexity for communication systems that require high symbol rates or low overall system costs. The ELGS has a high system complexity despite its average performance. Overall, the SWS, originally designed for multi-carrier systems, performs very poorly in single-carrier communications systems. Table 5.1 in Section 5 provides a ranking of each of the synchronization schemes in terms of the metrics set forth in Section 4.1. Details of comparison are given in Section 5. Based on the results presented in Table 5, it is safe to say that the most robust synchronization scheme examined in this work is the high-sample-rate Modified Sliding Window Synchronizer. A close second is its low-sample-rate cousin. The tradeoff between complexity and lowest mean-square phase error determines the rankings of the Gardner Zero-Crossing Detector and both versions of the Early-Late Gate Synchronizer. The least robust models are the high and low-sample-rate Sliding Window Synchronizers. Consequently, the recommended replacement synchronizer for NASA's Advanced Air Transportation Technologies mobile aeronautical communications system is the high-sample-rate Modified Sliding Window Synchronizer. By incorporating this synchronizer into their system, NASA can be assured that their system will be operational in extremely adverse conditions. The quick convergence time of the MSWS should allow the use of high-level protocols. However, if NASA feels that reduced system complexity is the most important aspect of their replacement synchronizer, the Gardner Zero-Crossing Detector would be the best choice.

  13. A mobile trusted computing architecture for a near field communication ecosystem

    Microsoft Academic Search

    Gerald Madlmayr

    2008-01-01

    Near Field Communication (NFC) is a wireless communication technology to transfer data over distances of up to 10 cm. With this technology, a mobile device is capable of emulating smartcards for access, payment or loyalty. The benefits of a mobile device with NFC over an ordinary smartcard are the interaction and network capabilities of such a device. Thus there is

  14. Technological Developments and Socio-Economic Issues of Wireless Mobile Communications.

    ERIC Educational Resources Information Center

    Beaubrun, Ronald; Pierre, Samuel

    2001-01-01

    Examines technological developments and the worldwide social-economic impacts of wireless mobile communications. Provides an overview of the technological developments of wireless mobile communications. Describes the evolution towards next-generation systems. Analyzes reasons for the growth rate of subscribers and the related social development.…

  15. Information communication scheme for loosely coupled mobile users in wireless sensor fields with multiple sources

    Microsoft Academic Search

    Euisin Lee; Fucai Yu; Min-Sook Jin; Sang-Ha Kim

    2009-01-01

    In wireless sensor networks, groups of mobile users interested in equivalent information could be classified into two categories according to existence of direct communication channel among the users: 1) loosely coupled user group and 2) tightly coupled user group. The loosely coupled group means that a mobile user should communicate with others via a wireless sensor network for querying, gathering,

  16. A new method of using preponderant terminal in cooperative satellite mobile communication system

    Microsoft Academic Search

    Jie Xiao; Feng Shaodong; Zhang Gengxin; Wang Fan

    2011-01-01

    In this paper, a new method of using pre- ponderant terminal in cooperative satellite mobile communication system was presented to reduce the influence of multipath fading and shading .First, the new method of using preponderant terminal in coopera- tive satellite mobile communication system was ana- lyzed?» then the system model was given and predi- gested to the typical three cooperative

  17. Stability and Control of Mobile Communications Systems With Time Varying Channels

    E-print Network

    Stability and Control of Mobile Communications Systems With Time Varying Channels Robert Buche, 2001 Abstract Consider the forward link of a mobile communications system with a single transmitter to the destination until transmitted. The main issues are the allocation of transmitter power and time to the various

  18. Stability and Control of Mobile Communications Systems With Time Varying Channels

    E-print Network

    Stability and Control of Mobile Communications Systems With Time Varying Channels Robert Buche Abstract Consider the forward link of a mobile communications system with a single transmitter and rather transmitted. The main issues are the allocation of transmitter power and time to the various queues in a queue

  19. A Joint Power and Subchannel Allocation Scheme Maximizing System Capacity in Indoor Dense Mobile Communication Systems

    Microsoft Academic Search

    Juyeop Kim; Dong-Ho Cho

    2010-01-01

    Indoor mobile communication systems (or simply indoor systems) are expected to yield significant improvement of capacity and coverage at low cost on mobile communication systems. However, the indoor system will likely be in dense environments, in which many cells exist in a small region, and a great portion of the coverage of a cell is overlapped by that of other

  20. Prediction of Fast Fading Mobile Radio Channels in Wideband Communication Systems

    E-print Network

    Dong, Liang

    , TX 78712 Abstract-- The fast fading mobile radio channels place fundamental limitationsPrediction of Fast Fading Mobile Radio Channels in Wideband Communication Systems Liang Dong. Introduction The radio channel in a wireless communication system is often characterized by multipath propa

  1. Rappaport, T. S., et al. "Mobile and Cellular Radio Communications" The Engineering Handbook.

    E-print Network

    Buehrer, R. Michael

    Rappaport, T. S., et al. "Mobile and Cellular Radio Communications" The Engineering Handbook. Ed. Richard C. Dorf Boca Raton: CRC Press LLC, 2000 © 1998 by CRC PRESS LLC #12;130 Mobile and Cellular Radio.4 Personal Communications System (PCS) 130.5 The Cellular Concept and System Fundamentals Frequency Reuse

  2. Energy-Efficient Wireless Communication based on Directional Transmission from Mobile Access

    E-print Network

    Zhong, Lin

    1 Energy-Efficient Wireless Communication based on Directional Transmission from Mobile Access 77025 Abstract The radio front-end (RF) is a major power consumer on mobile systems. In particularSwitch dynamically select the best antenna during active wireless transceiving without disrupting the communication

  3. Fireworks: An Adaptive Group Communications Protocol for Mobile Ad Hoc Networks

    E-print Network

    Krishnamurthy, Srikanth

    Fireworks: An Adaptive Group Communications Protocol for Mobile Ad Hoc Networks Lap Kong Law that move together. Thus, we develop Fireworks, an adaptive approach for group communications in mobile ad hoc networks. Fireworks is a hybrid two-tier multicast/broadcast pro- tocol that adapts to maintain

  4. Efficient simulation of TCP\\/IP for mobile wireless communications using importance sampling

    Microsoft Academic Search

    Zsolt Haraszti; J. Keith Townsend; James A. Freebersyser

    1998-01-01

    Future military communications systems are expected to exchange information in a seamless and reliable manner across heterogeneous networks composed of both fixed, wired nodes and mobile, wireless nodes. While commercial protocols such as TCP\\/IP have improved the seamlessness of military communications systems, the use of TCP\\/IP in the mobile, wireless environment for which it was not designed can have a

  5. Advanced interference rejection and anti-jam methods for low power mobile battlefield communications

    Microsoft Academic Search

    J. Scott Chuprun; Chad S. Bergstrom; Amy M. Guzek

    1997-01-01

    Mobile battlefield communication systems are called upon to operate effectively in increasingly adverse spectral environments. Obstacles to mobile battlefield communications include nonstationary command post co-site interference, ambient co-channel signals, and hostile jamming interferers. Typical interference levels encountered in a tactical environment can exceed the desired signal by 60 decibels. Such levels overwhelm the operational capabilities of current tactical radio systems.

  6. Designing a context-aware middleware for asynchronous communication in mobile ad hoc environments

    Microsoft Academic Search

    Mirco Musolesi

    2004-01-01

    In mobile ad hoc networks, synchronous communication mechanisms appear to be not suitable, since these assume that the involved entities are present at the same time during the interactions. On the other hand, asynchronous mechanisms seem to be better suited for mobile environments characterised with frequently intermittent connectivity. Therefore, message oriented middleware based on the asynchronous communication paradigm seems a

  7. Two-Armed, Mobile, Sensate Research Robot

    NASA Technical Reports Server (NTRS)

    Engelberger, J. F.; Roberts, W. Nelson; Ryan, David J.; Silverthorne, Andrew

    2004-01-01

    The Anthropomorphic Robotic Testbed (ART) is an experimental prototype of a partly anthropomorphic, humanoid-size, mobile robot. The basic ART design concept provides for a combination of two-armed coordination, tactility, stereoscopic vision, mobility with navigation and avoidance of obstacles, and natural-language communication, so that the ART could emulate humans in many activities. The ART could be developed into a variety of highly capable robotic assistants for general or specific applications. There is especially great potential for the development of ART-based robots as substitutes for live-in health-care aides for home-bound persons who are aged, infirm, or physically handicapped; these robots could greatly reduce the cost of home health care and extend the term of independent living. The ART is a fully autonomous and untethered system. It includes a mobile base on which is mounted an extensible torso topped by a head, shoulders, and two arms. All subsystems of the ART are powered by a rechargeable, removable battery pack. The mobile base is a differentially- driven, nonholonomic vehicle capable of a speed >1 m/s and can handle a payload >100 kg. The base can be controlled manually, in forward/backward and/or simultaneous rotational motion, by use of a joystick. Alternatively, the motion of the base can be controlled autonomously by an onboard navigational computer. By retraction or extension of the torso, the head height of the ART can be adjusted from 5 ft (1.5 m) to 6 1/2 ft (2 m), so that the arms can reach either the floor or high shelves, or some ceilings. The arms are symmetrical. Each arm (including the wrist) has a total of six rotary axes like those of the human shoulder, elbow, and wrist joints. The arms are actuated by electric motors in combination with brakes and gas-spring assists on the shoulder and elbow joints. The arms are operated under closed-loop digital control. A receptacle for an end effector is mounted on the tip of the wrist and contains a force-and-torque sensor that provides feedback for force (compliance) control of the arm. The end effector could be a tool or a robot hand, depending on the application.

  8. Mobile Continuous Reading This research focuses on mobile continuous reading

    E-print Network

    listening and the combination of both, all while reading content on a mobile device. We use web pages users. Four conditions were investigated in the study: visual-reading, audio-listening, manual, Measurement Introduction The mobile device is used with a short attention span and users are likely to switch

  9. The Mobile Data Challenge: Big Data for Mobile Computing Research

    E-print Network

    Do,Trinh-Minh-Tri

    few years smartphones remarkably started to carry sen- sors like GPS, accelerometer, gyroscope ­ by using large-scale mobile data as input to characterize and understand real-life phenomena, including scientific understanding of human and social phe- nomena, advanced mobile experiences and technological in

  10. Effect of user mobility on soft handoff performance in cellular communication

    Microsoft Academic Search

    Yali Qin; Xibing Xu; Ming Zhao; Yan Yao

    2002-01-01

    The handoff rate is a fundamental index to evaluate the handoff performance and as a result it affects the overall performance of a cellular mobile communication system. Meanwhile, moving patterns of mobiles are critical to the handoff rate. In this paper the effect of user's mobility on system handoff rate is studied The analytic result shows that the soft handoff

  11. Relation of user mobility to soft handoff rate in cellular communication

    Microsoft Academic Search

    Yali Qin; Xibing Xu; Ming Zhao; Yan Yao

    2002-01-01

    Handoff rate is a fundamental index to evaluate the handoff performance and as a result it affects the overall performance of cellular mobile communication system. Meanwhile, moving patterns of mobiles are critical to the handoff rate. In this paper the relation between user's mobility and system handoff rate is studied. The analytic result shows the soft handoff rate increases with

  12. Research on Mobile IP Routing of Space Network that Based on IP over CCSDS

    Microsoft Academic Search

    Li-zheng Jiang; Xin Meng; Sheng-bo Hu; Shu-qian Liu

    2007-01-01

    Space wideband information network technology is one of the hot technologies in studying of space technology, there are many difficult technologies need to be solved, for example, technologies of the connection and communication between space and ground heterogeneous network, algorithm of mobile routing, etc. The paper does research on these problems based on IP technology of the ground network and

  13. Incorporating guidelines for use of mobile technologies in health research and practice

    PubMed Central

    Young, Sean D.; Holloway, Ian W.; Swendeman, Dallas

    2014-01-01

    This commentary aims to create initial recommendations to guide researchers' decisions on the development and use of mobile technologies for public health research. We recommend that mobile technologies for public health research should be scalable and sustainable; draw on social, psychological and/or behavioral theoretical models; be able to be integrated with multiple communication devices; incorporate social network and/or geographic metrics and take a community-based participatory approach to development and implementation. All of these approaches are discussed. PMID:24713154

  14. Speech coding at 4800 bps for mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Gersho, Allen; Chan, Wai-Yip; Davidson, Grant; Chen, Juin-Hwey; Yong, Mei

    1988-01-01

    A speech compression project has recently been completed to develop a speech coding algorithm suitable for operation in a mobile satellite environment aimed at providing telephone quality natural speech at 4.8 kbps. The work has resulted in two alternative techniques which achieve reasonably good communications quality at 4.8 kbps while tolerating vehicle noise and rather severe channel impairments. The algorithms are embodied in a compact self-contained prototype consisting of two AT and T 32-bit floating-point DSP32 digital signal processors (DSP). A Motorola 68HC11 microcomputer chip serves as the board controller and interface handler. On a wirewrapped card, the prototype's circuit footprint amounts to only 200 sq cm, and consumes about 9 watts of power.

  15. Isolated and coupled superquadric loop antennas for mobile communications applications

    NASA Technical Reports Server (NTRS)

    Jensen, Michael A.; Rahmat-Samii, Yahya

    1993-01-01

    This work provides an investigation of the performance of loop antennas for use in mobile communications applications. The analysis tools developed allow for high flexibility by representing the loop antenna as a superquadric curve, which includes the case of circular, elliptical, and rectangular loops. The antenna may be in an isolated environment, located above an infinite ground plane, or placed near a finite conducting plate or box. In cases where coupled loops are used, the two loops may have arbitrary relative positions and orientations. Several design examples are included to illustrate the versatility of the analysis capabilities. The performance of coupled loops arranged in a diversity scheme is also evaluated, and it is found that high diversity gain can be achieved even when the antennas are closely spaced.

  16. Mobile tactical communications, the role of the UHF Follow-On satellite constellation and its successor, Mobile User Objective System

    Microsoft Academic Search

    J. Ingerski; A. Sapp

    2002-01-01

    The ultra high frequency (UHF) portion of the frequency spectrum is of great importance to the military for communications to the mobile warfighter. UHF has many advantages not available at other frequencies. UHF is used for both local line-of-site communications and worldwide military satellite communications (MILSATCOM). UHF Follow-On (UFO) is the satellite constellation used for narrowband MILSATCOM. UFO is used

  17. Patient-centered Communication Research

    Cancer.gov

    Several recent reports, including NCI's Strategic Plan for Leading the Nation and the NCI-designated cancer center directors' report Accelerating Successes Against Cancer, have recognized the salience of patient-clinician communication in optimizing cancer patients' and survivors' health outcomes.

  18. Communicating Qualitative Research Study Designs to Research Ethics Review Boards

    ERIC Educational Resources Information Center

    Ells, Carolyn

    2011-01-01

    Researchers using qualitative methodologies appear to be particularly prone to having their study designs called into question by research ethics or funding agency review committees. In this paper, the author considers the issue of communicating qualitative research study designs in the context of institutional research ethics review and offers…

  19. The iPad and mobile technology revolution: benefits and challenges for individuals who require augmentative and alternative communication.

    PubMed

    McNaughton, David; Light, Janice

    2013-06-01

    The iPad and other mobile technologies provide powerful new tools to potentially enhance communication for individuals with developmental disabilities, acquired neurogenic disorders, and degenerative neurological conditions. These mobile technologies offer a number of potential benefits, including: (a) increased awareness and social acceptance of augmentative and alternative communication (AAC), (b) greater consumer empowerment in accessing AAC solutions, (c) increased adoption of AAC technologies, (d) greater functionality and interconnectivity, and (e) greater diffusion of AAC research and development. However, there remain a number of significant challenges that must be addressed if these benefits are to be fully realized: (a) to ensure the focus is on communication, not just technology, (b) to develop innovative models of AAC service delivery to ensure successful outcomes, (c) to ensure ease of access for all individuals who require AAC, and, (d) to maximize AAC solutions to support a wide variety of communication functions. There is an urgent need for effective collaboration among key stakeholders to support research and development activities, and to ensure the successful implementation of mobile technologies to enhance communication outcomes for individuals who require AAC and their families. PMID:23705813

  20. Evaluation of Ad-Hoc and Mobility Architectures using Satellite Communications

    E-print Network

    Paris-Sud XI, Université de

    Evaluation of Ad-Hoc and Mobility Architectures using Satellite Communications Thierry Gayraud1 introduce difficulties (canyons, mountains, vegetation...). In such scenarios, communications in a group may be done using ad-hoc networks principle, but the communications from one group to another can be compared

  1. Communication-Aware Surveillance in Mobile Sensor Networks Alireza Ghaffarkhah and Yasamin Mostofi

    E-print Network

    Mostofi, Yasamin

    Communication-Aware Surveillance in Mobile Sensor Networks Alireza Ghaffarkhah and Yasamin Mostofi to a fixed base station, in the pres- ence of realistic fading communication channels. We develop a mathematical framework for robust communication-aware surveillance, in order to survey the environment

  2. WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 00: 117 (20xx)

    E-print Network

    Paris-Sud XI, Université de

    communication primitives, that are iii) data dissemination via broadcasting/geocasting, and iv) routing in bothWIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 00: 1­17 (20xx) Communication Protocols for Vehicular Ad hoc Networks Arnaud Casteigts1 , Amiya Nayak1 , and Ivan Stojmenovic1 1

  3. Investigation of single-hop connections between user terminals in geostationary mobile satellite communication systems

    Microsoft Academic Search

    Kazuhito Ebina; Nobuyuki Kataoka; Masazumi Ueba; Hideki Mizuno

    2001-01-01

    The number of subscribers in geostationary mobile satellite communication systems has been increasing, as a result of the increase voice communication between user terminals. In this situation, there is a strong demand to improve the communication quality of the double-hop connection between two user terminals. As an means of reducing the voice delay, we developed four single-hop connection methods in

  4. Towards THz Communications - Status in Research, Standardization and Regulation

    NASA Astrophysics Data System (ADS)

    Kürner, Thomas; Priebe, Sebastian

    2013-08-01

    In the most recent years, wireless communication networks have been facing a rapidly increasing demand for mobile traffic along with the evolvement of applications that require data rates of several 10s of Gbit/s. In order to enable the transmission of such high data rates, two approaches are possible in principle. The first one is aiming at systems operating with moderate bandwidths at 60 GHz, for example, where 7 GHz spectrum is dedicated to mobile services worldwide. However, in order to reach the targeted date rates, systems with high spectral efficiencies beyond 10 bit/s/Hz have to be developed, which will be very challenging. A second approach adopts moderate spectral efficiencies and requires ultra high bandwidths beyond 20 GHz. Such an amount of unregulated spectrum can be identified only in the THz frequency range, i.e. beyond 300 GHz. Systems operated at those frequencies are referred to as THz communication systems. The technology enabling small integrated transceivers with highly directive, steerable antennas becomes the key challenges at THz frequencies in face of the very high path losses. This paper gives an overview over THz communications, summarizing current research projects, spectrum regulations and ongoing standardization activities.

  5. A New mHealth Communication Framework for Use in Wearable WBANs and Mobile Technologies

    PubMed Central

    Hamida, Sana Tmar-Ben; Hamida, Elyes Ben; Ahmed, Beena

    2015-01-01

    Driven by the development of biomedical sensors and the availability of high mobile bandwidth, mobile health (mHealth) systems are now offering a wider range of new services. This revolution makes the idea of in-home health monitoring practical and provides the opportunity for assessment in “real-world” environments producing more ecologically valid data. In the field of insomnia diagnosis, for example, it is now possible to offer patients wearable sleep monitoring systems which can be used in the comfort of their homes over long periods of time. The recorded data collected from body sensors can be sent to a remote clinical back-end system for analysis and assessment. Most of the research on sleep reported in the literature mainly looks into how to automate the analysis of the sleep data and does not address the problem of the efficient encoding and secure transmissions of the collected health data. This article reviews the key enabling communication technologies and research challenges for the design of efficient mHealth systems. An end-to-end mHealth system architecture enabling the remote assessment and monitoring of patient's sleep disorders is then proposed and described as a case study. Finally, various mHealth data serialization formats and machine-to-machine (M2M) communication protocols are evaluated and compared under realistic operating conditions. PMID:25654718

  6. Research in space commercialization, technology transfer, and communications, volume 2

    NASA Technical Reports Server (NTRS)

    Dunn, D. A.; Agnew, C. E.

    1983-01-01

    Spectrum management, models for evaluating communication systems, the communications regulatory environment, expert prediction and consensus, remote sensing, and manned space operations research are discussed.

  7. Capacity anti-interference for simulation and research communication system on diversity technique

    NASA Astrophysics Data System (ADS)

    Li, Baohong

    2013-03-01

    Frequency-hopping communication is an effective technique for anti-interference, which has significant application value and vast development in such fields as military communication, mobile communication, wireless local area network and wireless personal communication. This article demonstrates the influence of several common man-made interferences on frequency-hopping system capacity and stresses the research on anti-interference capacity against some frequency bands. Based on simulation experiment, this article comes up with the improvement for frequency-hopping system in light of frequency diversity technique. The experiment shows that the improved frequency-hopping system's anti-interference capacity against some frequency bands has increased greatly.

  8. SUPPLEMENTAL EXPORT COMPLIANCE PROCEDURES FOR TRAVEL WITH MOBILE DEVICES & RESEARCH EQUIPMENT To ensure that SAO-affiliated persons, who work on export-controlled projects and travel with their

    E-print Network

    with their laptops and mobile devices, take additional export compliance security precautions in advance and bring WITH MOBILE DEVICES & RESEARCH EQUIPMENT policies related to mobile device security, as communicated by the CF to better secure export-controlled data on mobile devices. Devices can be compromised. The ITAR regulations

  9. A QoS guaranteed Mobile IP communication scheme with scalability in terms of resource management in backbone network

    Microsoft Academic Search

    Toshihiko KATO; Wei Liu; Seiji Ueno; Shuichi ITOH

    2003-01-01

    Resulting from the spread of the Mobile Internet, mobile communication with QoS guarantees will be required in order to realize mobile video interactions. So far, there are some studies which focused on QoS guaranteed Mobile IP communication, but they require backbone routers to maintain per flow QoS information for all individual mobile nodes. These approaches suffer from a lack of

  10. RESEARCH COMMUNICATION Identification of genes

    E-print Network

    Ahringe, Julie

    we used RNA interference (RNAi) to systemati- cally screen the nematode Caenorhabditis elegans ge by genome-wide RNAi Joris Pothof,1 Gijs van Haaften,1 Karen Thijssen,1 Ravi S. Kamath,2 Andrew G. Fraser,2/Cancer Research UK Institute and Department of Genetics, Cambridge CB2 1QR, UK An RNA interference (RNAi

  11. A fast algorithm based on MEI and FMM for field prediction in urban mobile communications

    Microsoft Academic Search

    Xiaoxing Yin; Xinyu Zai; Wei Hong; Xiaowei Zhu

    1999-01-01

    To meet the growing demand for high-capacity mobile communication services, micro-cell and pico-cell are now introduced. The prediction of the wave propagation in urban micro- and pico-cells is becoming very important in the design of a mobile communication system. In urban environments with many high buildings, the antenna height at the base station is usually below the level of the

  12. A guide to successful communications european research

    E-print Network

    Milano-Bicocca, Università

    developments (results, programmes, events, etc.). It is available in English, French and German. A free sample@cec.eu.int #12;A guide to successful communications european research #12;Europe Direct is a service to help you-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.5. Build good relationships with the journalists . . . 18 2.6. How to get onTV

  13. Michigan Center for Health Communications Research

    Cancer.gov

    Michigan Center for Health Communications Research Presented by: Victor J. Strecher, PhD, MPH Principal Investigator OUR GOAL Cost The goal: The goal: High efficacy High reach Cost High reach High efficacy eHealth “We are truly entering a new age

  14. Intercultural Communication Research: A Burke's Eye View.

    ERIC Educational Resources Information Center

    Jones, Tricia S.

    Kenneth Burke's concepts of rhetoric, dramatism, terministic screens (perceptual filters), and identification are used in this paper to justify and direct intercultural communication research. Three intercultural methodologies--cultural variable analysis, componential analysis, and ethnomethodology--are examined in the paper using these concepts.…

  15. Sales Communications in a Mobile World: Using the Latest Technology and Retaining the Personal Touch

    ERIC Educational Resources Information Center

    Norris, Daniel T.

    2007-01-01

    Salespeople increasingly have the opportunity to use technology to more quickly communicate with a larger number of clients and customers. Mobile technology, in particular, gives salespeople many advantages in rapidly reaching a large customer base. Furthermore, customers are increasingly employing mobile technology, making them increasingly…

  16. Dual-band omnidirectional microstrip patch array antenna for a mobile communication system

    Microsoft Academic Search

    T. Rutkowski; C. Peixeiro

    1997-01-01

    A dual-band omnidirectional microstrip patch antenna array is presented. The antenna will be used in the mobile terminal of a mobile communication system at 2 GHz. Four multilayer rectangular patches have been mounted on the sidewalls of a truncated pyramid. The main goal is to provide a received power as constant as possible along a typical elongated rectangular street cell

  17. WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2010; 10:547558

    E-print Network

    Jiang, Hai

    because of the time-varying network topology and propagation loss between any two nodes. QoS support access in an orderly manner among the mobile nodes such that efficiency can be achieved. Here, we focusWIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2010; 10:547­558 Published

  18. The relationship between mobile and fixed-line communications: A survey

    Microsoft Academic Search

    Ingo Vogelsang

    2010-01-01

    The dramatic worldwide increase in mobile communication that has led to more than 4 billion users has over the last few years been accompanied in wealthy countries by a significant decline in fixed network subscriptions. Such fixed-to-mobile substitution (FMS) is at the center of this literature survey. Theoretical models explaining FMS are scarce and are inconclusive regarding the balance between

  19. A New Paradigm for Mobile Multimedia Broadcasting Based on Integrated Communication and Broadcast Networks

    Microsoft Academic Search

    Zhisheng Niu; Long Long; Jian Song; Changyong Pan

    2008-01-01

    This article provides a new paradigm to integrate the Chinese digital television\\/terrestrial multimedia broadcasting (DTMB) systems with existing mobile communication systems, which can support mobile multimedia broadcasting services with carrier-grade quality. By dividing the services into four categories -digital TV, video on demand, data on demand, and Internet access - a complete design of the layered structure and signaling protocols

  20. Statistical characteristics of pedestrians' motion and effects on teletraffic of mobile communication networks

    Microsoft Academic Search

    Yuka Nagai; Takehiko Kobayashi

    2005-01-01

    Motion of mobile terminals greatly affects traffic characteristics (cell dwell time, handoff rates, channel occupancy lime of each base station, etc.) in mobile communication networks. Motion of vehicles was previously measured and characterized using the Global Positioning System, and its effects on traffic characteristics were examined. In this study, the authors measured pedestrian motion using an autonomous navigation system, analyzed

  1. IEEE Wireless Communications August 200466 1536-1284/04/$20.00 2004 IEEE Mobile station N

    E-print Network

    Shen, Xuemin "Sherman"

    IEEE Wireless Communications · August 200466 1536-1284/04/$20.00 © 2004 IEEE Mobile station N. In internetworking implementation, handoff performance should also be considered. Mobile IP handoff delay can approaches are actually only effective on registration signaling delays. For instance, a micro

  2. Impact of array processing techniques on the design of mobile communication systems

    Microsoft Academic Search

    V. A. N. Barroso; M. J. Rendas; J. P. Gomes

    1994-01-01

    Studies the application of adaptively steered arrays to mobile communications, particularly, in the design of base station antennas. System design issues are briefly reviewed on the basis of integration of those methods and the impact on transmitted power, co-channel reuse distance and spectrum efficiency is emphasized. Creating selective spatial channels enables to track the angular trajectory of each mobile and

  3. Rendering Adaptation to Address Communication and Computation Constraints in Cloud Mobile Gaming

    E-print Network

    California at San Diego, University of

    Rendering Adaptation to Address Communication and Computation Constraints in Cloud Mobile Gaming by the available server computing resource for each client, considering cloud server hosts numerous clients Shaoxuan Wang, Sujit Dey Mobile System Design Lab, Dept. of Electrical and Computer Engineering University

  4. Supporting terminal mobility by means of self-adaptive communication object migration

    Microsoft Academic Search

    Karin Anna Hummel; Szabolcs Póta; Christian Schusterreiter

    2005-01-01

    Mobile devices, like PDAs or smart phones, exhibit limited capabilities in terms of processing power and memory. Supported by advanced WLAN hotspot grid infrastructures, mobile terminals may enhance their computing capabilities significantly by utilizing remote resources in virtually shared spaces. Due to privacy and performance issues, the shared communication objects should be kept in proximity to the roaming owner which

  5. Structured P2P overlay of mobile brokers for realizing publish/subscribe communication in VANET.

    PubMed

    Pandey, Tulika; Garg, Deepak; Gore, Manoj Madhava

    2014-01-01

    Publish/subscribe communication paradigm provides asynchrony and decoupling, making it an elegant alternative for designing applications in distributed and dynamic environment such as vehicular ad hoc networks (VANETs). In this paradigm, the broker is the most important component that decouples other two components, namely, publisher and subscriber. Previous research efforts have either utilized the deployment of distributed brokers on stationary road side info-stations or have assigned the role of broker to any moving vehicle on ad hoc basis. In one approach, lots of preinstalled infrastructures are needed whereas, in another, the quality of service is not guaranteed due to unpredictable moving and stopping patterns of vehicles. In this paper, we present the architecture of distributed mobile brokers which are dynamically reconfigurable in the form of structured P2P overlay and act as rendezvous points for matching publications and subscriptions. We have taken city buses in urban settings to act as mobile brokers whereas other vehicles are considered to be in role of publishers and subscribers. These mobile brokers also assist in locating a vehicle for successful and timely transfer of notifications. We have performed an extensive simulation study to compare our approach with previously proposed approaches. Simulation results establish the applicability of our approach. PMID:24523629

  6. A Survey of Routing Techniques for Mobile Communications Networks

    Microsoft Academic Search

    S. Ramanathan; Martha Steenstrup

    1996-01-01

    . Mobile wireless networks pose interesting challenges for routing system design. To producefeasible routes in a mobile wireless network, a routing system must be able to accommodate roving users,changing network topology, and fluctuating link quality. We discuss the impact of node mobility and wirelesscommunication on routing system design, and we survey the set of techniques employed in or proposed forrouting

  7. A Contribution to Theory Building for Mobile Marketing: Categorizing Mobile Marketing Campaigns through Case Study Research

    Microsoft Academic Search

    Dietmar Georg Wiedemann

    2006-01-01

    Abstract Marketing experts consider the mobile device as an extremely promising marketing tool as it supports them tocope with their major challenge: getting time and attention from customers. Current mobile marketing research mostly covers success factors and acceptance analysis. Categorization, when addressed, lacks in appropriate foundation and is not linked to objectives atall. In this article we examine ,55 case

  8. Using Mobile Communication Technology in High School Education: Motivation, Pressure, and Learning Performance

    ERIC Educational Resources Information Center

    Rau, Pei-Luen Patrick; Gao, Qin; Wu, Li-Mei

    2008-01-01

    Motivation and pressure are considered two factors impacting vocational senior high school student learning. New communication technology, especially mobile communication technology, is supposed to be effective in encouraging interaction between the student and the instructor and improving learning efficiency. Social presence and information…

  9. On the adaptability of LTE services in mobile satellite communications systems

    Microsoft Academic Search

    Xianghui Hu; Xiaohan Xia; Hongguang Lan; Jianjun Wu

    2012-01-01

    In this paper we mainly discuss the adaptability of LTE services in satellite communications systems. Four groups of LTE services are introduced, including the service aspects and transport requirements. Meanwhile several satellite systems are also listed in this paper. Based on these parameters and conditions, the adaptability of LTE services in mobile satellite communications systems is preliminarily discussed in terms

  10. An implementation of a CMA adaptive array for high speed GMSK transmission in mobile communications

    Microsoft Academic Search

    Takeo Ohgane; Takanori Shimura; Naoto Matsuzawa; Hideichi Sasaoka

    1993-01-01

    The hardware implementation of an adaptive array as a technique for compensating multipath fading in mobile communications is described. The number of the antenna elements is four. The target communication system is modulated by 256 kbps Gaussian-filtered minimum shift keying (MSK) and has a time-division multiplexing (TDM) architecture with 24 time slots. Based on the digital beamforming concept, all of

  11. Adaptive resource reservation schemes for proportional DiffServ enabled fourth-generation mobile communications system

    Microsoft Academic Search

    Chenn-jung Huang; Yi-ta Chuang; Wei Kuang Lai; Yu-hang Sun; Chih-tai Guan

    2007-01-01

    Many mechanisms based on bandwidth reservation have been proposed in the literature to decrease connection dropping probability for handoffs in cellular communications. The handoff events occur at a much higher rate in packet-switched fourth generation mobile communication networks than in traditional cellular systems. An efficient bandwidth reservation mechanism for the neighboring cells is therefore critical in the process of handoff

  12. Communication power optimization in a sensor network with a path-constrained mobile observer

    Microsoft Academic Search

    Arnab Chakrabarti; Ashutosh Sabharwal; Behnaam Aazhang

    2006-01-01

    We present a procedure for communication power optimization in a network of randomly distributed sensors with an observer (data collector) moving on a fixed path. The key challenge in using a mobile observer is that it remains within communication range of any sensor for a brief duration, and inability to transfer data in this duration leads to data loss. We

  13. Digital mobile communication system designed for nationwide police activities-WIDE system

    Microsoft Academic Search

    R. Inoue

    1996-01-01

    In 1991, the National Police Agency (NPA) of Japan introduced a new type of digital mobile communication system, called the WIDE system, as a countermeasure against nationwide criminal cases. The WIDE system uses an exclusive radio network for police use. This enables police officers to communicate with each other at any time, even if the public network channels are all

  14. Large-scale Urban Vehicular Mobility for Networking Research

    E-print Network

    Fiore, Marco

    Large-scale Urban Vehicular Mobility for Networking Research Sandesh Uppoor, Marco Fiore Universit most distinguishing feature of vehicular networks simulation lies in the mobility of users, which is available today that captures both macroscopic and microscopic behaviors of drivers over a large urban

  15. Enhancing Field Research Methods with Mobile Survey Technology

    ERIC Educational Resources Information Center

    Glass, Michael R.

    2015-01-01

    This paper assesses the experience of undergraduate students using mobile devices and a commercial application, iSurvey, to conduct a neighborhood survey. Mobile devices offer benefits for enhancing student learning and engagement. This field exercise created the opportunity for classroom discussions on the practicalities of urban research, the…

  16. A survey of platforms for mobile networks research

    Microsoft Academic Search

    Earl Oliver; David R. Cheriton

    2008-01-01

    The use of smartphones is growing at an unprecedented rate and is projected to soon pass laptops as consumers' mobile platform of choice. The proliferation of these devices has created new opportunities for mobile researchers; however, when faced with hundreds of devices across nearly a dozen development platforms, selecting the ideal platform is often met with unanswered questions. In this

  17. A PCM-TDMA one dimensional mobile communication system using leaky coaxial cables

    NASA Astrophysics Data System (ADS)

    Sakata, S.; Saito, T.; Inose, H.

    1984-10-01

    In TDMA mobile communication systems, synchronization between a base station and mobile stations is a primary problem. This paper proposes a new mobile station synchronization scheme which does not require the propagation delay measurement or very long guard time for a one-dimensional mobile communication system using leaky coaxial cables (LCX). It shows that a large-capacity PCM-TDA mobile communication system can be realized based on the proposed synchronization scheme, and describes an application method for the train mobile communication system. Mobile station synchronization scheme, signal transmission system, and synchronization scheme between base stations are described. On the estimation of the attainable bit rate from the physical environment of the transmission paths, the required guard time length and the optimum burst length are determined, and the frame structure and the channel control method are described. To demonstrate the feasibility of the system, a signal transmission experiment using an LCX at the estimated maximum bit rate has been carried out and the possibility of high-speed pulse transmission by means of LCX has been confirmed.

  18. A communication theoretical analysis of FRET-based mobile ad hoc molecular nanonetworks.

    PubMed

    Kuscu, Murat; Akan, Ozgur B

    2014-09-01

    Nanonetworks refer to a group of nanosized machines with very basic operational capabilities communicating to each other in order to accomplish more complex tasks such as in-body drug delivery, or chemical defense. Realizing reliable and high-rate communication between these nanomachines is a fundamental problem for the practicality of these nanonetworks. Recently, we have proposed a molecular communication method based on Förster Resonance Energy Transfer (FRET) which is a nonradiative excited state energy transfer phenomenon observed among fluorescent molecules, i.e., fluorophores. We have modeled the FRET-based communication channel considering the fluorophores as single-molecular immobile nanomachines, and shown its reliability at high rates, and practicality at the current stage of nanotechnology. In this study, for the first time in the literature, we investigate the network of mobile nanomachines communicating through FRET. We introduce two novel mobile molecular nanonetworks: FRET-based mobile molecular sensor/actor nanonetwork (FRET-MSAN) which is a distributed system of mobile fluorophores acting as sensor or actor node; and FRET-based mobile ad hoc molecular nanonetwork (FRET-MAMNET) which consists of fluorophore-based nanotransmitter, nanoreceivers and nanorelays. We model the single message propagation based on birth-death processes with continuous time Markov chains. We evaluate the performance of FRET-MSAN and FRET-MAMNET in terms of successful transmission probability and mean extinction time of the messages, system throughput, channel capacity and achievable communication rates. PMID:25014963

  19. Research on Context-Aware Mobile Computing

    Microsoft Academic Search

    Li Han; Jyri P. Salomaa; Jian Ma; Kuifei Yu

    2008-01-01

    Context-aware mobile computing belongs to the field of ubiquitous computing. It aims to enable device to provide better service for people through applying available context information. In this paper, context-aware mobile computing was elaborated. Firstly, the history of definition of context was summarized, and then the new classification of human-centric context was proposed. The acquiring and application of context information

  20. Children's Literature in the Undergraduate Course on Communication Research Methods

    ERIC Educational Resources Information Center

    Brown, Daniel S.

    2010-01-01

    Objective: Students will develop positive attitudes toward communication research by linking new values and principles with the familiar values and principles contained in children's literature. Course: Communication Research Methods.

  1. TDMA-Based Dual-Mode Communication for Mobile Wireless Sensor Networks

    PubMed Central

    Mehta, Ankur; Kerkez, Branko; Glaser, Steven D.; Pister, Kristofer S. J.

    2012-01-01

    Small highly mobile robots, and in particular micro air vehicles (MAVs), are well suited to the task of exploring unknown indoor environments such as buildings and caves. Such a task imposes a number of requirements on the underlying communication infrastructure, with differing goals during various stages of the mission. This work addresses those requirements with a hybrid communications infrastructure consisting of a stationary mesh network along with the mobile nodes. The combined network operates in two independent modes, coupling a highly efficient, low duty cycle, low throughput mode for routing and persistent sensing with a burst mode for high data rate communication. By strategically distributing available frequency channels between the mobile agents and the stationary nodes, the overall network provides reliable long-term communication paths while maximizing data throughput when needed. PMID:23443374

  2. 4308 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, VOL. 6, NO. 12, DECEMBER 2007 Joint Scale-Lag Diversity in Wideband Mobile

    E-print Network

    Schniter, Philip

    -Lag Diversity in Wideband Mobile Direct Sequence Spread Spectrum Systems Adam R. Margetts, Member, IEEE, Philip of mobility on a wideband direct sequence spread spectrum (DSSS) communication system, and study a scale

  3. Geometrically based directional channel model for urban mobile communication systems

    Microsoft Academic Search

    Yasuhiro ODA; Koichi TSUNEKAWA; Masaharu HATA

    2000-01-01

    This paper proposes a geometrically based propagation model for an urban mobile environment that establishes a relationship between the angle-of-arrival and time-of-arrival of multipath components. The model is characterized by the geometric locations of a base station and mobile station among urban city structures. This model comprises three sets of propagation characteristics: the street-microcell propagation characteristics around mobile stations; the

  4. On the design of security protocols for mobile communications

    Microsoft Academic Search

    Yi Mu; Vijay Varadharajan

    1996-01-01

    . Use of mobile personal computers in open networked environmentis revolutionalising the way we use computers. Mobile networkedcomputing is raising important information security and privacy issues.This paper is concerned with the design of authentication protocols fora mobile computing environment. The paper first analyses the authenticationinitiator protocols proposed by Beller,Chang and Yacobi (BCY)and the modifications considered by Carlsen and points out

  5. Research Report Acupuncture mobilizes the brain's default mode and its

    E-print Network

    Napadow, Vitaly

    Research Report Acupuncture mobilizes the brain's default mode and its anti-correlated network work has shown that acupuncture stimulation evokes deactivation of a limbic­ paralimbic and functional connectivity of these regions during acupuncture vs. tactile stimulation and vs. acupuncture

  6. Reliable Real-Time Communication in Cooperative Mobile Applications

    E-print Network

    independent communication part that constitutes the real-time and reliability hardcore of the system and timely to the group of cooperating systems. It is based on the communication hardcore, which provides, the development of the communication hardcore is the most challenging task. On the one hand, to be usable

  7. A shortest path algorithm for mobile satellite communication network

    Microsoft Academic Search

    Zhang Tao; Zhang Jun; Liu Zhong Kan

    2005-01-01

    Mobile satellite network is a special time-varying network. Some classical network theories used in the current terrestrial networks, such as the shortest path algorithm, cannot be applied to it availably. In this paper, based on the proposed model of mobile satellite network, the classical shortest path algorithm of fixed topological network, such as the Dijkstra algorithm, is proved to be

  8. Multimodal biometric authentication using quality signals in mobile communications

    Microsoft Academic Search

    Josef Bigün; Julian Fiérrez-aguilar; Javier Ortega-garcia; Joaquin Gonzalez-rodriguez

    2003-01-01

    The elements of multimodal authentication along with system models are presented. These include the machine experts as well as machine supervisors. In particular finger- print and speech based systems will serve as illustration of a mobile authentication application. A novel signal adap- tive supervisor, based on the input biometric signal quality is evaluated. Experimental results on data collected from mobile

  9. Alternative metrics for hard handoffs in mobile communication

    Microsoft Academic Search

    Raymond M. Bendett; Perambur S. Neelakanta

    2000-01-01

    Handoff (or handover) refers to a crucial effort by a particular mobile unit to change from its serving base station to another as warranted by dynamic variations in link quality caused by mobility and interference\\/fading considerations. Classically, the handover initiation is done by a decision algorithm based on received signal strengths (RSSs) from the serving and prospective base stations. That

  10. Secure Positioning of Mobile Terminals with Simplex Radio Communication

    Microsoft Academic Search

    Mikio Fujii

    2006-01-01

    With the rapid spread of various mobile terminals in our society, the importance of secure position- ing is growing for wireless networks in adversarial settings. Recently, several authors have proposed a secure positioning mechanism of mobile terminals which is based on the geometric property of wire- less node placement, and on the postulate of mod- ern physics that a propagation

  11. Laser Communication Demonstration System (LSCS) and Future Mobile Satellite Services

    NASA Technical Reports Server (NTRS)

    Chen, C. -C.; Lesh, J. R.

    1995-01-01

    The Laser Communications Demonstration System (LCDS) is a proposed in-orbit demonstration of high data rate laser communications technology conceived jointly by NASA and U.S. industry. The program objectives are to stimulate industry development and to demonstrate the readiness of high data rate optical communications in Earth Orbit. For future global satellite communication systems using intersatellite links (ISLs), laser communications technology can offer reduced mass , reduced power requirements, and increased channel bandwidths without regulatory restraint. This paper provides comparisons with radio systems and status of the program.

  12. Stochastic differential equations for modeling, estimation and identification of mobile-to-mobile communication channels

    Microsoft Academic Search

    Mohammed M. Olama; Seddik M. Djouadi; Charalambos D. Charalambous

    2009-01-01

    Mobile-to-mobile networks are characterized by node mobility that makes the propagation environment time varying and subject to fading. As a consequence, the statistical characteristics of the received signal vary continuously, giving rise to a Doppler power spectral density (DPSD) which varies from one observation instant to the next. The current models do not capture and track the time varying characteristics.

  13. Mobile teleoperator research at Savannah River Laboratory

    SciTech Connect

    Byrd, J S

    1985-01-01

    A Robotics Technology Group was organized at Savannah River Laboratory to employ modern automation and robotics for applications at the Savannah River site. Several industrial robots have been installed in plant processes. Other robotics systems are under development in the laboratories, including mobile teleoperators for general remote tasks and emergency response operations. This paper discusses present work on a low-cost wheeled mobile vehicle, a modular light duty manipulator arm, a large gantry telerobot system, and a high technology six-legged walking robot with a teleoperated arm.

  14. [Pilot plan for a mobile health communication and monitoring system for people with diabetes].

    PubMed

    Alcayaga, Claudia; Pérez, Janet Carola; Bustamante, Claudia; Campos, Solange; Lange, Ilta; Zuñiga, Francisca

    2014-01-01

    mHealth is a practical, useful, and available tool for one-way or two-way communication between health professionals and patients. It is especially promising in countries such as Chile, with widespread and growing mobile telephone coverage that is very well accepted by the public. Our objective is to demonstrate the process for designing a mobile communication and monitoring model, aimed at providing communication between professionals in primary healthcare centers and their patients, to facilitate timely diagnosis and initiation of treatment for type 2 diabetes. This model's characteristics include use of mobile telephones as a communication tool, a one-way method (from health centers to patients), integration into in-person care delivered at health centers, use of different communication strategies (voice and written), and integrated functioning using open-source software. The system includes personalized communication, automated voice communication, and automated written communication using short message service (SMS). We describe the strategies and components of the system. The lessons learned include the contribution from successful implementation of COSMOS (consolidated online modulated operating systems), a technological innovation, to support the health care of people with suspected type 2 diabetes in primary healthcare centers. Working together with teams in the field is essential to this achievement. PMID:25211577

  15. Mobile Networks and Applications 2 (1997) 285301 285 Communication protocol design to facilitate re-use based on the

    E-print Network

    Khan, Javed I.

    1997-01-01

    formal descriptions for communication protocols and the effective development methodologies usedMobile Networks and Applications 2 (1997) 285­301 285 Communication protocol design to facilitate varying error rates. Similarly, handoff procedures create situations where dynamically determined change

  16. Prospects for Technical Communication: Research for Futures Needs.

    ERIC Educational Resources Information Center

    Mathes, J. C.

    The need for technical communication to enable the transition from a "postindustrial" future to an alternative future is incalculable; however, research is required to improve current technical communication models and methods. The current rhetoric of technical communication derives from an inadequate command-generated technical communication

  17. The Mobile Agents Integrated Field Test: Mars Desert Research Station April 2003

    NASA Technical Reports Server (NTRS)

    Clancey, William J.; Sierhuis, Maarten; Alena, Rick; Crawford, Sekou; Dowding, John; Graham, Jeff; Kaskiris, Charis; Tyree, Kim S.; vanHoof, Ron

    2003-01-01

    The Mobile Agents model-based, distributed architecture, which integrates diverse components in a system for lunar and planetary surface operations, was extensively tested in a two-week field "technology retreat" at the Mars Society s Desert Research Station (MDRS) during April 2003. More than twenty scientists and engineers from three NASA centers and two universities refined and tested the system through a series of incremental scenarios. Agent software, implemented in runtime Brahms, processed GPS, health data, and voice commands-monitoring, controlling and logging science data throughout simulated EVAs with two geologists. Predefined EVA plans, modified on the fly by voice command, enabled the Mobile Agents system to provide navigation and timing advice. Communications were maintained over five wireless nodes distributed over hills and into canyons for 5 km; data, including photographs and status was transmitted automatically to the desktop at mission control in Houston. This paper describes the system configurations, communication protocols, scenarios, and test results.

  18. Battery consumption and handoff examination of a cellular ad-hoc united communication system for operational mobile robots

    Microsoft Academic Search

    Tomoko Adachi; Masao Nakagawa

    1998-01-01

    A hybrid system in which mobile terminals (MTs) themselves select whether to communicate directly or via base stations (BSs) from communication conditions, “cellular ad hoc united communication system”, has been proposed by Adachi and Nakagawa (1996). It has been confirmed to have effective channel usage, especially for MTs which tend to communicate with partners which are close together, such as

  19. Communication satellite studies applicable to mobile telephone services

    NASA Technical Reports Server (NTRS)

    Anderson, R. E.; Milton, R. T.; Brown, J. P.

    1979-01-01

    The potential use of satellites as extensions of existing terrestrial land mobile systems is discussed. Compatibility, particularly with cellular type systems, is considered. Sample technical and cost parameters and market assessments are also presented.

  20. Estimation of the demand for public services communications. [market research and economic analysis for a communications satellite system

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Market analyses and economic studies are presented to support NASA planning for a communications satellite system to provide public services in health, education, mobile communications, data transfer, and teleconferencing.

  1. Low cost Ku-band electronic steerable array antenna for mobile satellite communications

    Microsoft Academic Search

    Stefano Vaccaro; Daniel Llorens del Rio; Jose Padilla; Rens Baggen

    2011-01-01

    This paper presents the results of the development of an active phased array antenna for Ku-Band Receive-only mobile satellite communications realised within the ESA-project NATALIA. The phased array antenna is designed for mobile satellite services and dedicated for automotive applications. An overview of the complete build-up will be provided as well as the current status of the multilayer Printed Circuit

  2. Military communications satellite system multiplies UHF channel capacity for mobile users

    Microsoft Academic Search

    D. Wadsworth

    1999-01-01

    The mobile user objective system (MUOS) will be the successor to the Navy's UFO satellite communications system. One MUOS proposal relies on a constellation of GEO spacecraft that uses non-processing repeaters and multiple spotbeams for worldwide Earth-coverage. UHF frequency reuse greatly increases the number of narrowband voice\\/data channels available to mobile units. A key design element is the large antenna

  3. Smart low-power CMOS cameras for 3G mobile communicators

    Microsoft Academic Search

    M. Ansorge; S. Tanner; X. Shi; J. Bracamonte; J.-L. Nagel; P. Stadelmann; F. Pellandini; P. Seitz; N. Blanc

    2002-01-01

    The paper presents the concept of a smart multifunctional low-power camera for 3G mobile communicators and Personal Digital Assistants. The device is composed of an ultra low-power image sensor featuring a large intra-scene dynamic range and a high sensitivity, so as to ensure proper image acquisition under possibly severe illumination conditions, as encountered in mobile. Further embedded functionalities encompass low-power

  4. A model for local\\/mobile radio communications with correct packet capture

    Microsoft Academic Search

    R. Clark Robertson; Tri T. Ha

    1992-01-01

    The performance of a local\\/mobile radio communications system utilizing the slotted ALOHA multiple random access protocol is analyzed. The probability of correct packet capture is evaluated for a local\\/mobile packet radio system using ideal coherent binary phase-shift keying (BPSK) modulation. Both the near\\/far effect and the effect of Rayleigh fading on the probability of correct packet capture are taken into

  5. Cross layer design for mobile Ad-Hoc Unmanned Aerial Vehicle communication networks

    Microsoft Academic Search

    Abdel Ilah Alshbatat; Liang Dong

    2010-01-01

    A Mobile Ad-Hoc Network (MANET) is a popular type of wireless network that is formed by a collection of mobile nodes. Each node in such network has the capability to communicate with its neighbors and non-neighbors through a wireless medium without using any existing network infrastructure. Due to the lack of infrastructure, all nodes in Ad-Hoc network are designed to

  6. Recasting Communication Theory and Research: A Cybernetic Approach.

    ERIC Educational Resources Information Center

    Hill, Gary A.

    The author's main concern is to provide a research format which will supply a unitary conception of communication. The wide range of complex topics and variety of concepts embraced by communication theory and the rather disparate set of phenomena encompassed by communication research create this need for a unitary study approach capable of linking…

  7. Delay-tolerant communication using mobile robotic helper nodes

    Microsoft Academic Search

    Daniel Henkel; Timothy X Brown

    2008-01-01

    Delay tolerant networks can exhibit long phases of complete unconnectedness, where several nodes will not be able to communicate effectively. In those circumstances controlling the movement of helper nodes, that facilitate message exchanges instead of relying on direct communication, can improve network performance. We investigate when controlled movement is beneficial and how helper nodes need to move or position themselves

  8. Mobile Learning Application Research Based on iPhone

    Microsoft Academic Search

    Zong Hu; Dongming Huang

    \\u000a In recent years, as a new mode of learning, more and more domestic and foreign scholars pay attention to mobile learning.\\u000a This paper use iPhone act as mobile learning carrier, learners can get and interact information through iPhone. Application\\u000a research based on iPhone will maximize the potential advantages of iPhone, so that learners can participate in learning at\\u000a anytime, in

  9. Providing Undergraduate Research Opportunities for Communication Students: A Curricular Approach.

    ERIC Educational Resources Information Center

    Rodrick, Rick; Dickmeyer, Linda

    2002-01-01

    Notes that undergraduate research can provide transformative educational experiences and profoundly impact the teaching of communication. Discusses the benefits of undergraduate research experiences and the challenges of teaching research methods in communication. Presents a structure for incorporating a capstone undergraduate research experience…

  10. Intercultural Communication Research: Where Do We Go from Here?

    ERIC Educational Resources Information Center

    Porter, Richard E.

    This paper presents an outline of intercultural communication research needs and offers proposals for research direction for the next decade. The author suggests the following goals and criteria: (1) extend existing theory to encompass intercultural communication; (2) concentrate on intercultural research rather than cross-cultural research; (3)…

  11. [The role of mobile communication devices in the spread of infections].

    PubMed

    Morvai, Júlia; Szabó, Rita

    2015-05-17

    Mobile communication devices have an invaluable feature of communication within hospital, and they may support certain aspects of clinical diagnosis and education. However, there may be a risk for contamination of these devices with various pathogens. The aim of the authors was to perform a systematic review on the potential role of mobile communication devices in the dissemination of pathogens and to identify effective prevention measures. A detailed literature search was conducted using PubMed and ScienceDirect databases for papers published in English between January, 2004 and August, 2014. With the use of specific search term combinations 30 of the 216 articles met the inclusion criteria. It was found that only 8% of healthcare workers routinely cleaned their mobile communication devices resulting in a high rate of contamination (40-100%). Coagulase-negative Staphylococci and Staphylococcus aureus were the most commonly identified bacteria and most of them were methicillin resistant (10-95.3%). This systematic review identified effective interventions to reduce bacterial contamination risks including staff education, hand hygiene and regular decontamination of mobile communication devices. PMID:26038946

  12. Laser Communication Demonstration System (LCDS) and future mobile satellite services

    NASA Technical Reports Server (NTRS)

    Chen, Chien-Chung; Wilhelm, Michael D.; Lesh, James R.

    1995-01-01

    The Laser Communications Demonstration System (LCDS) is a proposed in-orbit demonstration of high data rate laser communications technology conceived jointly by NASA and U.S. industry. The program objectives are to stimulate industry development and to demonstrate the readiness of high data rate optical communications in Earth orbit. For future global satellite communication systems using intersatellite links, laser communications technology can offer reduced mass and power requirements and higher channel bandwidths without regulatory constraints. As currently envisioned, LCDS will consist of one or two orbiting laser communications terminals capable of demonstrating high data rate (greater than 750Mbps) transmission in a dynamic space environment. Two study teams led by Motorola and Ball Aerospace are currently in the process of conducting a Phase A/B mission definition study of LCDS under contracts with JPL/NASA. The studies consist of future application survey, concept and requirements definition, and a point design of the laser communications flight demonstration. It is planned that a single demonstration system will be developed based on the study results. The Phase A/B study is expected to be completed by the coming June, and the current results of the study are presented in this paper.

  13. Ad-Hoc Communication and Localization System for Mobile Robots

    NASA Astrophysics Data System (ADS)

    Neuwinger, Bernd; Witkowski, Ulf; Rückert, Ulrich

    Robots exploring unknown territory cannot rely on fixed infrastructure for communication and localization purposes. Therefore an ad-hoc communication and localization system is required to provide such facilities. In this paper a solution for a radio based localization system is presented using a 2.4 GHz wireless radio transceiver based on Chirp Spread Spectrum (CSS) modulation, which allows distance measurements by evaluating the signal propagation delay. Using odometry data as additional information source a communication and positioning system is developed fulfilling ad-hoc demands.

  14. Cross Platform Solution of Communication and Voice\\/Graphical User Interface for Mobile Devices in Vehicles

    Microsoft Academic Search

    Géza Németh; Géza Kiss; Bálint Tóth

    \\u000a Two long-term goals of our study has been to develop a standardized communication interface between the mobile device and\\u000a other onboard systems and to create a parametrical, scaleable user interface, both with voice and graphical user input\\/output.\\u000a This chapter describes the main requirements, principles, and aspects of a voice\\/graphical user interface and of a Bluetooth\\u000a based communication interface. Requirements and

  15. Mobile phones and elderly people: a noisy communication.

    PubMed

    Stamato, Cláudia; Moraes, Anamaria de

    2012-01-01

    Knowing the users is capital for building user-friendly digital interfaces. One way to think about the users is considering their familiarity with this technology. This article presents the results of twelve interviews with elderly people residing in the so-called South Zone of Rio de Janeiro (Brazil) who have used mobile phones over at least one year. It is part of the Doctor's Thesis "Mobile phones for elderly people - usability for social integration" ("Celulares para idosos - usabilidade a serviço da integração social"), which is targeted at ascertaining if the current mobile phones are user-friendly for elderly people. Through the technique of Guided Interviews, we found usage time, criteria for choice of phones, reasons for changes, preferences, and manners of use. Preliminarily, we have noticed differences in the behavior of the participating users and performed a qualitative analysis according to groups of age and gender. PMID:22316743

  16. Satellite-aided land mobile communications system implementation considerations

    NASA Technical Reports Server (NTRS)

    Leroy, B. E.

    1982-01-01

    It was proposed that a satellite-based land mobile radio system could effectively extend the terrestrial cellular mobile system into rural and remote areas. The market, technical and economic feasibility for such a system is studied. Some of the aspects of implementing an operational mobile-satellite system are discussed. In particular, two key factors in implementation are examined: (1) bandwidth requirements; and (2) frequency sharing. Bandwidth requirements are derived based on the satellite antenna requirements, modulation characteristics and numbers of subscribers. Design trade-offs for the satellite system and potential implementation scenarios are identified. Frequency sharing is examined from a power flux density and modulation viewpoint. Previously announced in STAR as N82-25290

  17. IEEE Communications Magazine July 2002108 Standardization of Mobile Phone

    E-print Network

    Han, Richard Y.

    answering point (PSAP) attendants of wireless communications networks must be able to know a 911 caller to an appropriate PSAP and related emergency assistance attendants. In 1999 the FCC decided to tighten the Phase II

  18. Autonomous interactive intermediaries : social intelligence for mobile communication agents

    E-print Network

    Marti, Stefan Johannes Walter, 1965-

    2005-01-01

    Today's cellphones are passive communication portals. They are neither aware of our conversational settings, nor of the relationship between caller and callee, and often interrupt us at inappropriate times. This thesis is ...

  19. Rayleigh fading channels in mobile digital communication systems .I. Characterization

    Microsoft Academic Search

    Bernard Sklar

    1997-01-01

    When the mechanisms of fading channels were first modeled in the 1950s and 1960s, the ideas were primarily applied to over-the-horizon communications covering a wide range of frequency bands. The 3-30 MHz high-frequency (HF) band is used for ionospheric communications, and the 300 MHz-3 GHz ultra-high-frequency (UHF) and 3-30 GHz super-high-frequency (SHF) bands are used for tropospheric scatter. Although the

  20. A systems approach to the commercialization of space communications technology - The NASA\\/JPL Mobile Satellite Program

    Microsoft Academic Search

    William J. Weber III; Valerie W. Gray; Byron Jackson; Laura C. Steele

    1991-01-01

    This paper discusss the systems approach taken by NASA and the Jet Propulsion Laboratory in the commercialization of land-mobile satellite services (LMSS) in the United States. As the lead center for NASA's Mobile Satellite Program, JPL was involved in identifying and addressing many of the key barriers to commercialization of mobile satellite communications, including technical, economic, regulatory and institutional risks,

  1. Modeling, Performance Analysis and Comparison of Two Level Single Chain Pointer Forwarding Strategy For Location Management in Wireless Mobile Communication

    E-print Network

    Kant, C R; Prakash, N; Kant, Chhaya Ravi; Prakash, Nupur

    2006-01-01

    Global wireless networks enable mobile users to communicate regardless of their locations. Location management is an important part of the emerging wireless and mobile technology. A Personal Communication System (PCS) network must have an efficient way to keep track of the mobile users to deliver services effectively. Global System for Mobile Communication (GSM) is a commonly accepted standard for mobility management of mobile users. Location management involves location tracking, and location information storage. Location management requires mobile users to register at various registration areas whenever they are on the move. The registration process may cause excessive signaling traffic and long service delays. To improve the efficiency of location tracking and avoid call set up delays, several strategies such as local anchor scheme, per-user caching scheme and several pointer forwarding schemes have been proposed in the past. In this paper, we propose a new "Two Level Single Chain Pointer Forwarding (TLSCP...

  2. Energy locality: processing\\/communication\\/interface tradeoffs to optimize energy in mobile systems

    Microsoft Academic Search

    D. Siewiorek

    2001-01-01

    Summary form only given, as follows. As computers continue to shrink, research and commercial interest in mobile\\/wearable computing is rapidly growing. Unlike traditional desktop computing in which the user is required to come to the computer, mobile computing brings the computer to the user. Mobile\\/wearable computers represent the next evolutionary step in the trend toward more people-centric computing. One of

  3. Near-field communication-based secure mobile payment service

    Microsoft Academic Search

    Kiran S. Kadambi; Jun Li; Alan H. Karp

    2009-01-01

    The loss of customer account information makes headlines all too often. The Payment Card Industry (PCI) Data Security Standard (DSS) has generated resistance from merchants because of its cost and complexity. Unfortunately, innovating in the Point of Sale (PoS) space is hard because the protocols have been standardized, tightly constraining new ideas. Using mobile phones as payment devices opens up

  4. Acculturation and Communicative Mobility Among Former Soviet Nationalities.

    ERIC Educational Resources Information Center

    Haarmann, Harald; Holman, Eugene

    1997-01-01

    Discusses the strategies that the former Soviet states are evolving to balance the interests of dominant ethnic groups with those of linguistic minorities while constructing a national identity, highlighting language policy in action and focusing on acculturation processes and geographic mobility among groups. A case study of Estonia is also…

  5. Department of Mobile Communications 2229, route des Crtes

    E-print Network

    Gesbert, David

    . Named Media Independent Handover Services, this standard enables in addition the mobility to and from on the media dependent mapping of the IEEE 802.21 to LTE. Index Terms Heterogeneous networks, Handover, MIH, IEEE 802.21, LTE, EPS. #12;#12;Contents 1 Introduction

  6. Channel Modeling and Simulation in Satellite Mobile Communication Systems

    Microsoft Academic Search

    Branka Vucetic; Jun Du

    1992-01-01

    An analog model describing signal amplitude and phase variations on shadowed satellite mobile channels is proposed. A linear combination of log-normal, Rayleigh, and Rice models is used to describe signal variations over an area with constant environment attributes while an M-state Markov chain is applied to represent environment parameter variations. Channel parameters are evaluated from the experimental data and utilized

  7. Mobility-Tolerant Reliable Wireless LAN Multicast Communication

    Microsoft Academic Search

    V. Shankar; S. K. S. Gupta

    Reliable single-hop wireless multicast is needed for vario us applications such as multicast file transfer in a smart classroom. Mobility and wireless channel characteristics such as high bit error rate (BER) and the hidden terminal problem make providing reliability a challenging task. Further, due to the broadcast nature of the wireless medium, feedback packets such as acknowledgements and control packets

  8. Study on Wireless Behavior of Mobile Communications using

    E-print Network

    Yu, Chansu

    a higher loss of data rate due to numerous interferences and they have lower transmission rates. Background be simply described as the ability to use technology untethered. Two main aspects play a big role in mobile.11 protocol in the late 1990's played a big role in connecting these small handheld devices to the information

  9. Nomadic Pict: Correct Communication Infrastructure for Mobile Computation

    E-print Network

    Sewell, Peter

    flexibili* *ty, a wide-area programming language of the high level into the low level; we builtsNomadichPict,ould provide a low-* *level abstraction that makes distribu- a distributed programming language and verificationaoflin-gorithm. The languages c* *ited above have particular algo- frastructure for mobile computation

  10. Collaborating with Your Clients Using Social Media & Mobile Communications

    ERIC Educational Resources Information Center

    Typhina, Eli; Bardon, Robert E.; Gharis, Laurie W.

    2015-01-01

    Many Extension educators are still learning how to effectively integrate social media into their programs. By using the right social media platforms and mobile applications to create engaged, online communities, Extension educators can collaborate with clients to produce and to share information expanding and enhancing their social media and…

  11. Edgar Nett Mobile Computer Communication SS'14 1 General Overview

    E-print Network

    Access Control Telecommunication Systems Satellite Systems Broadcast Systems Wireless LAN Mobile Network.g. historic buildings, firewalls) q more robust against disasters like, e.g., earthquakes, fire - or users aspect) l difficult to predict (real-time aspect) q Transmission errors l tremendously higher loss rates

  12. Privacy and Security in Mobile Health (mHealth) Research

    PubMed Central

    Arora, Shifali; Yttri, Jennifer; Nilsen, Wendy

    2014-01-01

    Research on the use of mobile technologies for alcohol use problems is a developing field. Rapid technological advances in mobile health (or mHealth) research generate both opportunities and challenges, including how to create scalable systems capable of collecting unprecedented amounts of data and conducting interventions—some in real time—while at the same time protecting the privacy and safety of research participants. Although the research literature in this area is sparse, lessons can be borrowed from other communities, such as cybersecurity or Internet security, which offer many techniques to reduce the potential risk of data breaches or tampering in mHealth. More research into measures to minimize risk to privacy and security effectively in mHealth is needed. Even so, progress in mHealth research should not stop while the field waits for perfect solutions.

  13. Satellite Communications for Aeronautical Applications: Recent research and Development Results

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.

    2001-01-01

    Communications systems have always been a critical element in aviation. Until recently, nearly all communications between the ground and aircraft have been based on analog voice technology. But the future of global aviation requires a more sophisticated "information infrastructure" which not only provides more and better communications, but integrates the key information functions (communications, navigation, and surveillance) into a modern, network-based infrastructure. Satellite communications will play an increasing role in providing information infrastructure solutions for aviation. Developing and adapting satellite communications technologies for aviation use is now receiving increased attention as the urgency to develop information infrastructure solutions grows. The NASA Glenn Research Center is actively involved in research and development activities for aeronautical satellite communications, with a key emphasis on air traffic management communications needs. This paper describes the recent results and status of NASA Glenn's research program.

  14. 48 CFR 6.302-3 - Industrial mobilization; engineering, developmental, or research capability; or expert services.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... false Industrial mobilization; engineering, developmental, or research capability...302-3 Industrial mobilization; engineering, developmental, or research capability...To establish or maintain an essential engineering, research, or development...

  15. 48 CFR 6.302-3 - Industrial mobilization; engineering, developmental, or research capability; or expert services.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... false Industrial mobilization; engineering, developmental, or research capability...302-3 Industrial mobilization; engineering, developmental, or research capability...To establish or maintain an essential engineering, research, or development...

  16. 48 CFR 6.302-3 - Industrial mobilization; engineering, developmental, or research capability; or expert services.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... false Industrial mobilization; engineering, developmental, or research capability...302-3 Industrial mobilization; engineering, developmental, or research capability...To establish or maintain an essential engineering, research, or development...

  17. 48 CFR 6.302-3 - Industrial mobilization; engineering, developmental, or research capability; or expert services.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... false Industrial mobilization; engineering, developmental, or research capability...302-3 Industrial mobilization; engineering, developmental, or research capability...To establish or maintain an essential engineering, research, or development...

  18. Characteristics of large deployable mesh reflector antennas for future mobile communications satellites

    Microsoft Academic Search

    Takashi Ebisui; Akio Iso; Teruaki Orikasa; Toshio Sugimoto; Shin-Ichi Sato

    1992-01-01

    A large deployable antenna is essential for effective mobile communication satellites. This paper describes the key technologies needed for such an antenna, the development plan, and the characteristics of various scale models. The electrical scale models of the mesh reflector antenna and the mechanical models of the deployable reflector have been constructed to aid in antenna design. The ultimate goal

  19. How Can Mobile SMS Communication Support and Enhance a First Year Undergraduate Learning Environment?

    ERIC Educational Resources Information Center

    Jones, Geraldine; Edwards, Gabriele; Reid, Alan

    2009-01-01

    In this paper we discuss a case study investigating how the academic and personal development of first year students on an undergraduate sports education degree can be supported and enhanced with mobile SMS (Short Message Service) communication. SMS-based technologies were introduced in response to students' particular needs (in transition to…

  20. SHF Cassegrain antenna with electronic beam squint tracking for high data rate mobile satellite communication systems

    Microsoft Academic Search

    B. Rama Rao; L. P. Callahan; R. J. Davis

    1994-01-01

    The design of pointing and tracking systems for vehicular antennas required for a high data rate mobile military satellite communication system is a daunting task because of its demanding requirements. Not only does the antenna have to be satellite pointed accurately towards the satellite as the vehicle moves rapidly and changes orientation, but it must also do so under scintillations

  1. Transmission bandwidth improvement by directive antenna in urban mobile radio communication

    Microsoft Academic Search

    Tsutomu Takeuchi; Fumio Ikegami; Susumu Yoshida

    1986-01-01

    The transmission bandwidth in urban areas determines the maximum transmission rate of digital mobile communication. A directive antenna can have an effect of broadening the transmission bandwidth by itself. The transmission bandwidth improvement of proposed antenna pattern diversity reception (APDR) is estimated by computer simulation based on the measured fading data received by directive antennas in urban areas, with two

  2. Intercarrier interference self-cancellation scheme for OFDM mobile communication systems

    Microsoft Academic Search

    Yuping Zhao; Sven-Gustav Häggman

    2001-01-01

    For orthogonal frequency-division multiplexing (OFDM) communication systems, the frequency offsets in mobile radio channels distort the orthogonality between subcarriers resulting in intercarrier interference (ICI). This paper studies an efficient ICI cancellation method termed ICI self-cancellation scheme. The scheme works in two very simple steps. At the transmitter side, one data symbol is modulated onto a group of adjacent subcarriers with

  3. A DUAL-POLARIZED WIDE-BAND PATCH ANTENNA FOR INDOOR MOBILE COMMUNICATION APPLICA- TIONS

    Microsoft Academic Search

    M. Secmen; A. Hizal

    This paper proposes the conflguration of a dual- polarized wide-band patch antenna system suitable for indoor mobile communication applications. This conflguration consists of two patch antennas, which have difierent feed structures from classical patch antenna conflguration. These antennas, which are separated by a thin absorber to have a good isolation, are fed independently to obtain dual polarization. The antenna structure

  4. Edgar Nett Mobile Computer Communication SS'14 13 Access methods SDMA/FDMA/TDMA

    E-print Network

    Communication SS'14 16 Aloha (pure/slotted) - dynamic TDMA with (no/little) control sender A sender B sender C collision t Aloha sender A sender B sender C collision t Slotted Aloha #12;Edgar Nett Mobile Computer load) only 18% (Aloha), 36% (Slotted Aloha) (assuming Poisson distribution for packet arrival

  5. Development of superconductive microwave filters for mobile communications and filter banks

    Microsoft Academic Search

    B. Marcilhac; Y. Lemaitre; D. Mansart; J. C. Mage

    1999-01-01

    The development of superconductive microwave filters connected to the use of cooled electronics is now in the critical phase of system integration. All the different steps of filter development, design and fabrication must be controlled, reproducible and technically realisable by conventional microelectronics tools. We developed filters for mobile communications and filter banks with the goal of optimising these aspects. Lanthanum

  6. Dynamic 3G network selection for increasing the competition in the mobile communications market

    Microsoft Academic Search

    Gwenael Le Bodic; Demessie Girma; J. Irvine; J. Dunlop

    2000-01-01

    This paper proposes a market-based framework in which service providers, network operators and users are able to trade communications services. For this purpose, a middleware has been specified in which software agents can supply or purchase QoS contracts. Benefits from the proposal are increased competition in the provision of mobile services, an integrated framework for the management of services and

  7. WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2009; 9:705717

    E-print Network

    Jiang, Hai

    WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2009; 9:705­717 Published-tolerable localization in wireless sensor networks with inaccurately positioned anchor nodes Rongfei Fan1 , Hai Jiang1 Summary Localization is essential for wireless sensor networks (WSNs). It is to determine the positions

  8. Low-profile penta-band monopole antenna for mobile communication applications

    Microsoft Academic Search

    Yu Han; Junhong Wang; Meie Chen; Zhan Zhang

    2011-01-01

    An internal monopole antenna with compact size is proposed in this paper, which can be applied to mobile communications, and its frequency band covers GSM850, GSM900, DCS, PCS, UMTS bands simultaneously. It is comprised of a driven monopole and a coupled loop strip. By inserting a folded slit in the driven rectangular patch, two wide bands are achieved. The antenna

  9. Telephone traffic in mobile radio communication system using dynamic frequency assignments

    Microsoft Academic Search

    M. Sengoku

    1980-01-01

    Traffic characteristics of a mobile radio communication system using a dynamic channel assignment scheme which has all channels available at all base stations are derived. In the system with one channel, the traffic characteristics in each zone are exactly obtained. For a multichannel operation, some approximation methods are proposed and some simple examples are also presented.

  10. The land mobile satellite communication channel-recording, statistics, and channel model

    Microsoft Academic Search

    Erich Lutz; Daniel Cygan; Michael Dippold; Frank Dolainsky; Wolfgang Papke

    1991-01-01

    The communication channel between the MARECS satellite at 26°W and a cruising van was measured and recorded in European areas exhibiting satellite elevations from 13 to 43°. Different environments and mobile antennas were tested. The results of an extensive statistical evaluation include spectra of the fading amplitude; probability density, and distribution of the received signal power; and the percentage of

  11. Low cost electronically steered antenna and receiver system for mobile satellite communications

    Microsoft Academic Search

    J. I. Alonso; J. M. Blas; L. E. Garcia; J. Ramos; J. de Pablos; J. Grajal; G. G. Gentili; J. Gismero; F. Perez

    1996-01-01

    The design, construction, and basic characteristics of an electronically steered, adaptive phased array antenna for land mobile satellite communications are described here. The antenna system includes an array of six microstrip stacked patch antennas, each one connected to an RF channel, which include a monolithic microwave\\/millimeter wave integrated circuit (MMIC) low noise amplifier and a commercial silicon monolithic I-Q modulator.

  12. WILEY WIRELESS COMMUNICATIONS AND MOBILE COMPUTING 1 DSP Implementation of a Bit Loading

    E-print Network

    Kansas, University of

    WILEY WIRELESS COMMUNICATIONS AND MOBILE COMPUTING 1 DSP Implementation of a Bit Loading Algorithm Abstract In this paper, we present a proof-of-concept, fixed-point, DSP hardware implementation loading, DSP implementation. I. INTRODUCTION Deployed in a wide range of high data rate transmission

  13. Using proxy cache relocation to accelerate Web browsing in wireless\\/mobile communications

    Microsoft Academic Search

    Stathes Hadjiefthymiades; Lazaros F. Merakos

    2001-01-01

    Mobile computing is considered of major importance to the computing industry for the forthcoming years due to the progress in the wireless communications area. A proxy-based architecture for accelerating Web browsing in cellular customer premises networks (CPN) is presented. Proxy caches, maintained in base stations, are constantly relocated to accompany the roaming user. A cache management scheme is proposed, which

  14. Proxies + Path Prediction: Improving Web Service Provision in Wireless-Mobile Communications

    Microsoft Academic Search

    Stathes Hadjiefthymiades; Lazaros F. Merakos

    2003-01-01

    Mobile computing is considered of major importance to the computing industry for the forthcoming years due to the progress in the wireless communications area. A proxy-based architecture for accelerating Web browsing in wireless customer premises networks is presented. Proxy caches, maintained in base stations, are constantly relo- cated to accompany the roaming user. A cache management scheme is proposed, which

  15. A simple formation-tracking controller of mobile robots based on a "spanning-tree" communication

    E-print Network

    Boyer, Edmond

    show that a simple condition on the reference angular velocity (persistency of excitation) suffices robots. In [7], an adaptive leader-follower based formation control without the need of leaders' velocityA simple formation-tracking controller of mobile robots based on a "spanning-tree" communication

  16. IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 56, NO. 5, MAY 2008 743 Mobility Enhanced Smart Antenna Adaptive

    E-print Network

    Krishnamurthy, Vikram

    IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 56, NO. 5, MAY 2008 743 Mobility Enhanced Smart Antenna, and it is observed that load balancing between sectors is achieved and which greatly reduces the effect of hot spot voice/data services. Its RAKE receiver design and soft handoff greatly increase the robustness against

  17. Analysis of handoff initiation using different path loss models in mobile communication system

    Microsoft Academic Search

    Geetam S. Tomar; Shekhar Verma

    2006-01-01

    Handoff is the mechanism that transfers an ongoing call from one cell to another as a user moves through the coverage area of a cellular system. Handoff is the key operation in cellular mobile communication system, which is accomplished by the system and is unperceptible for the user. In this paper, the received signal strength from the two base stations

  18. Investigating the boundary effect of a multimedia TDMA personal mobile communication network simulation

    Microsoft Academic Search

    Aldo G. Orozco Lugo; F. A. Cruz Prez; G. Hernandez Valdez

    2001-01-01

    The boundary effect in multimedia TDMA personal mobile communication network simulation is investigated. We evaluate the performance of several channel assignment strategies (CASs) for multi-rate traffic calls in a Manhattan-like microcellular environment under two different simulation topologies. These are the wrapped around topology, which minimize the boundary effect, and the unwrapped topology, which ignore it. Both, uniform traffic and uneven

  19. MILCOM 2004-2004 IEEE MilitaryCommunications Conference ANONYMOUS HANDSHAKES IN MOBILE AD HOC NETWORKS

    E-print Network

    Latchman, Haniph A.

    MILCOM 2004- 2004 IEEE MilitaryCommunications Conference ANONYMOUS HANDSHAKES IN MOBILE AD HOC- vides the desirable sender and receiver anonymity, as well as the relationship anonymity of the sender the leakage of nodal identity informationl . This situation necessitates the development of anonymous com

  20. Securing against fraud in mobile communications : system design and development in 3G mobile networks

    E-print Network

    Mochizuki, Yujiro, 1973-

    2006-01-01

    Network security ensures the consistency, integrity, and reliability of telecommunications systems. Authorized network access prevents fraudulent communications and maintains the availability of the systems. However, limited ...

  1. R&D of a Next Generation LEO System for Global Multimedia Mobile Satellite Communications

    NASA Astrophysics Data System (ADS)

    Morikawa, E.; Motoyoshi, S.; Koyama, Y.; Suzuki, R.; Yasuda, Y.

    2002-01-01

    Next-generation LEO System Research Center (NeLS) was formed in the end of 1997 as a research group under the Telecommunications Advancement Organization of Japan, in cooperation with the telecommunications operators, manufacturers, universities and governmental research organization. The aim of this project is to develop new technology for global multimedia mobile satellite communications services with a user data rate around 2Mbps for handy terminals. component of the IMT-2000, and the second generation of the big-LEO systems. In prosecuting this project, two-phase approach, phase 1 and phase 2, is considered. Phase 1 is the system definition and development of key technologies. In Phase 2, we plan to verify the developed technology in Phase 1 on space. From this year we shifted the stage to Phase 2, and are now developing the prototype of on-board communication systems for flight tests, which will be planed at around 2006. The satellite altitude is assumed to be 1200 km in order to reduce the number of satellites, to avoid the Van Allen radiation belts and to increase the minimum elevation angle. Ten of the circular orbits with 55 degree of inclination are selected to cover the earth surface from -70 to 70 degree in latitude. 12 satellites are positioned at regular intervals in each orbit. In this case, the minimum elevation angle from the user terminal can be keep more than 20 degree for the visibility of the satellite, and 15 degree for simultaneous visibility of two satellites. Then, NeLS Research Center was focusing on the development of key technologies as the phase 1 project. Four kinds of key technologies; DBF satellite antenna, optical inter-satellite link system, satellite network technology with on-board ATM switch and variable rate modulation were selected. Satellite Antenna Technology: Development of on-board direct radiating active phased array antenna with digital beam forming technology would be one of the most important breakthroughs for the satellite communication systems. Therefore, the experimental DBF network with 16 radiating elements was developed for confirming a basic signal processing performance. A/D sampled data are processed by using FPGA circuit for beam forming by real-time basis. Optical Inter-Satellite Link Technology: The inter-satellite link (ISL) technology is also important, because the inter-satellite network is essential to realize the low delay network connection for multimedia services. The optical ISL simulator was developed for the study of optical modem and optical tracking mechanism. And the sensitivity of 56 photons/bit at 10-9 of error rate has been achieved by employing the Erbium doped fiber amplifier, polarizing filter and narrow band optical filter. Coude path type, the active universal joint (AUJ) type and two flat mirror type of optical antenna mechanism were developed. Satellite Network Technology: For constructing this optical ISL ring, the utilization of wavelength division multiplexing (WDM) technology is envisaged. By applying WDM technology to the optical intra-orbital ISL, logical mesh connections can be achieved by assigning the appropriate wavelength for the links among satellites. By using inclined orbit, inter-orbital ISL connection can be keep continuously. Therefore, WDM technology is also applicable to the inter-orbital ISL network. The satellite ATM network simulator was developed in order to investigate the effect of delay fluctuation caused by the satellite constellations. This simulator works as real-time basis by using commercial ATM switches and personal computers. This simulator was installed Dijkstra's algorithm to determine satellite routing path in order to minimize the end-to-end delay time from the source terminal to the destination terminal. The satellite IP network simulator has been developed in order to evaluate the congestion of the multimedia traffic. Variable Rate Modulation Technology: Considering the propagation impairments in the mobile conditions, we employ the variable rate transmission, which maintains the communication service

  2. Design of a Mobile Agent-Based Adaptive Communication Middleware for Federations of Critical Infrastructure Simulations

    NASA Astrophysics Data System (ADS)

    Görbil, Gökçe; Gelenbe, Erol

    The simulation of critical infrastructures (CI) can involve the use of diverse domain specific simulators that run on geographically distant sites. These diverse simulators must then be coordinated to run concurrently in order to evaluate the performance of critical infrastructures which influence each other, especially in emergency or resource-critical situations. We therefore describe the design of an adaptive communication middleware that provides reliable and real-time one-to-one and group communications for federations of CI simulators over a wide-area network (WAN). The proposed middleware is composed of mobile agent-based peer-to-peer (P2P) overlays, called virtual networks (VNets), to enable resilient, adaptive and real-time communications over unreliable and dynamic physical networks (PNets). The autonomous software agents comprising the communication middleware monitor their performance and the underlying PNet, and dynamically adapt the P2P overlay and migrate over the PNet in order to optimize communications according to the requirements of the federation and the current conditions of the PNet. Reliable communications is provided via redundancy within the communication middleware and intelligent migration of agents over the PNet. The proposed middleware integrates security methods in order to protect the communication infrastructure against attacks and provide privacy and anonymity to the participants of the federation. Experiments with an initial version of the communication middleware over a real-life networking testbed show that promising improvements can be obtained for unicast and group communications via the agent migration capability of our middleware.

  3. An Admission Control-based Benefit Optimization Model for Mobile Communications: the Effect of a Decision Time Budget

    Microsoft Academic Search

    Kuo-Chung Chu; Chun-sheng Wang; Frank Yeong-Sung Lin

    2010-01-01

    In mobile communication systems, a soft handoff (SHO) technique is used to optimize the quality and capacity of communications.\\u000a However, because the handoff process incurs a high overhead there must be a tradeoff between the system capacity and the handoff\\u000a overhead. In this paper, we propose a benefit optimization model for mobile communications. The model tries to maximize the\\u000a overall

  4. A study and experiment plan for digital mobile communication via satellite

    NASA Technical Reports Server (NTRS)

    Jones, J. J.; Craighill, E. J.; Evans, R. G.; Vincze, A. D.; Tom, N. N.

    1978-01-01

    The viability of mobile communications is examined within the context of a frequency division multiple access, single channel per carrier satellite system emphasizing digital techniques to serve a large population of users. The intent is to provide the mobile users with a grade of service consistant with the requirements for remote, rural (perhaps emergency) voice communications, but which approaches toll quality speech. A traffic model is derived on which to base the determination of the required maximum number of satellite channels to provide the anticipated level of service. Various voice digitalization and digital modulation schemes are reviewed along with a general link analysis of the mobile system. Demand assignment multiple access considerations and analysis tradeoffs are presented. Finally, a completed configuration is described.

  5. Design of an anti-Rician-fading modem for mobile satellite communication systems

    NASA Technical Reports Server (NTRS)

    Kojima, Toshiharu; Ishizu, Fumio; Miyake, Makoto; Murakami, Keishi; Fujino, Tadashi

    1995-01-01

    To design a demodulator applicable to mobile satellite communication systems using differential phase shift keying modulation, we have developed key technologies including an anti-Rician-fading demodulation scheme, an initial acquisition scheme, automatic gain control (AGC), automatic frequency control (AFC), and bit timing recovery (BTR). Using these technologies, we have developed one-chip digital signal processor (DSP) modem for mobile terminal, which is compact, of light weight, and of low power consumption. Results of performance test show that the developed DSP modem achieves good performance in terms of bit error ratio in mobile satellite communication environment, i.e., Rician fading channel. It is also shown that the initial acquisition scheme acquires received signal rapidly even if the carrier-to-noise power ratio (CNR) of the received signal is considerably low.

  6. Investigations of outdoor-to-indoor mobile-to-mobile radio communication channels

    Microsoft Academic Search

    Istvan Z. Kovacs; Patrick C. F. Eggers; Kim Olesen; Leif G. Petersen

    2002-01-01

    The mobile-to-mobile radio channel was investigated in different suburban outdoor-to-indoor environments. System performance parameters in terms of un-encoded BER and outage probability have been extracted from hardware and software TETRA simulations. In several scenarios, the measured signal envelope statistics were found to be a combination of single and double Rayleigh distributions. The system performances obtained in these scenarios were in

  7. Multipath link and modem design for satellite mobile communications

    NASA Astrophysics Data System (ADS)

    Gardner, F. M.

    1983-08-01

    Modems for digital L-band communication between satellites and aircraft, ships, and land vehicles are discussed. Low-rate, low-cost communications for small users is desired, so antennas are nonsteerable. Received signal-to-noise ratios are small so power conservation is critically important. Reflections from the Earth's surface have significant amplitude and cause multipath interference to the desired signal. Data rates of 100, 1200, and 4800 bps were considered. Modulation types examined include BPSK/DPSK, FSK, and GMSK. Digital implementation of the modems is proposed wherever feasible.

  8. Future directions in communication research: individual health behaviors and the influence of family communication.

    PubMed

    Baiocchi-Wagner, Elizabeth A

    2015-08-01

    Although numerous fields continue to advance research toward various areas of health prevention, communication researchers have yet to examine fully the link between communication and health improvement. This is particularly true of those studying the intersections of family and health communication-unfortunate, given that family members serve as primary socialization agents in health attitudes and behaviors. Using the example of obesity-related health behaviors, the following essay advances the argument that continued research aimed at understanding the intersection of health and families' communicative influence may help to illuminate the nature, causes, and redress to health issues that are correlated with individual health practices. This is accomplished by (a) reviewing contributions and limitations of pioneering studies in (family) health literature and (b) offering three key research areas for health communication exploration that will move scholars toward communication-based solutions (e.g., family-level communication health interventions). PMID:24837245

  9. ORIGINAL RESEARCH COMMUNICATION Differential Antibacterial Activity Against Pseudomonas

    E-print Network

    Paris-Sud XI, Université de

    ORIGINAL RESEARCH COMMUNICATION Differential Antibacterial Activity Against Pseudomonas aeruginosa spontaneously liberating CO. The nature of the metal in CO-RMs also modulates the anti-bacterial effect

  10. An Integrated Routing and Scheduling Approach for Persistent Vehicle Communication in Mobile WiMAX Mesh Networks

    Microsoft Academic Search

    Rahul Amin; Kuang-Ching Wang; Parmesh Ramanathan

    2007-01-01

    The U.S. military has recently announced plans to evaluate the IEEE 802.16e Mobile WiMAX technology's potentials as a fast deployable solution for building a broadband tactical communication network. Specifically, the technology's provisions of mesh mode operation and terminal mobility allow a tactical network to be quickly deployed among mobile base stations and mobile battle units. The technology provides essential support

  11. A Study of Key Communicators in Research and Development Laboratories

    ERIC Educational Resources Information Center

    Chakrabarti, Alok K.; O'Keefe, Robert D.

    1977-01-01

    The purposes of this study were to identify key communicators within a sample of Research and Development laboratories, to explore those factors which motivate individuals to assume and maintain the role of key communicators, and to derive implications for further study of the characteristics of key communicators in R & D laboratories. (Author)

  12. Student as Communication Skills Trainer: From Research to "Concept Keys"

    ERIC Educational Resources Information Center

    Bodie, Graham D.

    2008-01-01

    Although textbooks are filled with practical communication advice, many students overlook the importance of basing practical advice about communication on quality research. This oversight is important for two reasons. First, given the explosion of self-help remedies focused on communication, students should learn to distinguish between…

  13. A Bibliometric Evaluation of Core Journals in Communication Research.

    ERIC Educational Resources Information Center

    Reeves, Byron; Borgman, Christine

    The citation study technique, known as bibliometrics, was undertaken in this study to evaluate scholarly exchange among the core journals in the field of communication. The journals studied were "Central States Speech Journal,""Communication Research,""Journal of Broadcasting,""Journal of Communication,""Journalism Quarterly,""Public Opinion…

  14. Communication Research and Instruction for an Uncertain Tomorrow.

    ERIC Educational Resources Information Center

    Work, William

    This paper considers the future of communication research and instruction in an age when the communication environment is under stress from such factors as communication overload, language "pollution," and a widespread and growing disregard for truth. Items related to the general thesis are considered from three perspectives: the role of…

  15. Strategies and Techniques for Communicating Concrete Pavement Research

    Microsoft Academic Search

    Mark Anderson-Wilk

    Technology transfer is a set of activities intended to lead to the eventual implementation of new products and methods. The paper seeks to explain the importance of communications in technology transfer efforts and how specific communications approaches and techniques can be used to move research findings to interested audiences. Examples are provided from the communications program of the National Concrete

  16. EXPLORATORY RESEARCH ON COMMUNICATION ABILITIES AND CREATIVE ABILITIES.

    ERIC Educational Resources Information Center

    TAYLOR, CALVIN W.; AND OTHERS

    THIS STUDY SOUGHT TO IDENTIFY VARIABLES RELATED TO EFFECTIVENESS OF COMMUNICATION IN MILITARY OPERATIONS. THE GOAL WAS TO DEVELOP TESTS TO CLASSIFY OFFICERS AND AIRMEN, BASED UPON ALL OF THE BROAD COMMUNICATION ABILITIES NEEDED IN THE AIR FORCE. THE RESEARCH OUTLINE CONSISTED OF REVIEWING COMMUNICATION STUDIES AND OTHER TESTS, PREPARING A REDUCED…

  17. iPads, mobile technologies, and communication applications: a survey of family wants, needs, and preferences.

    PubMed

    Meder, Allison M; Wegner, Jane R

    2015-03-01

    Families of children with communication disabilities were surveyed to explore wants and preferences relative to mobile media technology, including iPads, as a form of augmentative and alternative communication (AAC). The families surveyed reported wanting information and support from professionals, including speech language pathologists (SLPs), who are knowledgeable about AAC. These families wanted devices to meet their children's individual needs and reported that ease of use and affordability were the most influential characteristics in the purchase of mobile media devices and communication applications. SLPs who understand family decision making can utilize collaborative clinical decision making that respects families' wants and needs, while also focusing on device feature matching and family education. PMID:25685882

  18. Distributed Extremum Seeking and Cooperative Control for Mobile Communication

    E-print Network

    Ingram, Mary Ann

    ) and searches autonomously for the optimal spacings based on typical communication models. Simulation results function or its variations to achieve desired formation as well as collision avoidance [9]. In addition Shannon capacity outage probability. Hence, connectivity is maintained if the outage probability is less

  19. Joint multipath-Doppler diversity in mobile wireless communications

    Microsoft Academic Search

    Akbar M. Sayeed; Behnaam Aazhang

    1999-01-01

    We introduce a new approach for achieving diversity in spread-spectrum communications over fast-fading multipath channels. The RAKE receiver used in existing systems suffers from significant performance degradation due to the rapid channel variations encountered under fast fading. We show that the Doppler spread induced by temporal channel variations in fact provides another means for diversity that can be further exploited

  20. Communication and Sensing Trade-Offs in Decentralized Mobile Sensor Networks: A Cross-Layer Design Approach

    E-print Network

    Murray, Richard M.

    Communication and Sensing Trade-Offs in Decentralized Mobile Sensor Networks: A Cross-Layer Design the trade-offs between communication and sensing objectives, by determining the optimal sensor configurations when introducing imperfect communication. We further illustrate the performance degradation caused

  1. WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2004; 4:318 (DOI: 10.1002/wcm.160)

    E-print Network

    Lim, Sunho

    reservation; handoff 1. Introduction As cellular networks are envisioned to be a ubiquitous communicationWIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2004; 4:3­18 (DOI: 10 to the movement of users during communication sessions, one of the most important QoS factors is related

  2. NFC on Mobile Phones: Issues, Lessons and Future Research

    Microsoft Academic Search

    Vassilis Kostakos; Eamonn O'neill

    2007-01-01

    In this paper we discuss some issues arising from our implementation and evaluation of two systems that enable mobile phone users to identify common address book contacts. These systems were implemented using Bluetooth and NFC. Here we discuss development and deployment issues, users' perceptions and preferences, and suggest promising future research directions.

  3. Research and Technology in Wave Energy for Electric Mobility

    E-print Network

    Frandsen, Jannette B.

    Research and Technology in Wave Energy for Electric Mobility Reza Ghorbani Assistant Professor marine energy resources that are available for our utilization. These include wave energy, energy generated by ocean current and energy extraction through ocean thermal conversion (OTEC). For wave energy

  4. MEASURE AND MOBILE-MEASURE MODELS - RESEARCH/OPERATION/SUPPORT

    EPA Science Inventory

    EPA's Office of Research and Development (ORD) has been working in cooperation with the Georgia Institute of Technology, EPA's Office of Transportation and Air Quality (OTAQ), and the Federal Highway Administration to develop a new concept in mobile source emissions modeling. Thi...

  5. VIRGINIA POLYTECHNIC INSTITUTE & STATE UNIVERSITY MOBILE & PORTABLE RADIO RESEARCH GROUP

    E-print Network

    Al-Ghadhban, Samir

    VIRGINIA POLYTECHNIC INSTITUTE & STATE UNIVERSITY MOBILE & PORTABLE RADIO RESEARCH GROUP MPRG VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY Tech Virginia 1 8 7 2 Performance Evaluation samir@kfupm.edu.sa http://faculty.kfupm.edu.sa/EE/samir/ 1 #12;VIRGINIA POLYTECHNIC INSTITUTE & STATE

  6. RESEARCH PAPER Responses of leaf nitrogen and mobile carbohydrates in

    E-print Network

    RESEARCH PAPER Responses of leaf nitrogen and mobile carbohydrates in different Quercus species; environmental changes; global warming; non-structural carbohydrates; oak; soluble sugars; starch. Correspondence. For example, drought was found to influence the rnetabolism of soluble carbohydrates (Hanson & Hitz 1982

  7. Stochastic Differential Equations for Modeling, Estimation and Identification of Mobile-to-Mobile Communication Channels

    SciTech Connect

    Olama, Mohammed M [ORNL; Djouadi, Seddik M [ORNL; Charalambous, Prof. Charalambos [University of Cyprus

    2009-01-01

    Mobile-to-mobile networks are characterized by node mobility that makes the propagation environment time varying and subject to fading. As a consequence, the statistical characteristics of the received signal vary continuously, giving rise to a Doppler power spectral density (DPSD) which varies from one observation instant to the next. The current models do not capture and track the time varying characteristics. This paper is concerned with dynamical modelling of mobile-to-mobile channels, parameter estimation and identification from received signal measurements. The evolution of the propagation environment is described by stochastic differential equations. In particular, it is shown that the parameters of the models can be determined by approximating the band-limited DPSD using the Gauss-Newton method. However, since the DPSD is not available online, we propose to use a filter-based expectation maximization algorithm and Kalman filter to estimate the channel parameters and states, respectively. The scheme results in a finite dimensional filter which only uses the first and second order statistics. The algorithm is recursive allowing the inphase and quadrature components and parameters to be estimated online from received signal measurements. The algorithms are tested using experimental data collected from moving sensor nodes in indoor and outdoor environments demonstrating the method s viability.

  8. Mobile Marketing in the Retailing Environment: Current Insights and Future Research Avenues

    Microsoft Academic Search

    Venkatesh Shankar; Alladi Venkatesh; Charles Hofacker; Prasad Naik

    2010-01-01

    Mobile marketing, which involves two- or multi-way communication and promotion of an offer between a firm and its customers using the mobile, a term that refers to the mobile medium, device, channel, or technology, is growing in importance in the retailing environment. It has the potential to change the paradigm of retailing from one based on consumers entering the retailing

  9. Research of the mobile-code-based file system for portable information device

    Microsoft Academic Search

    Yurong Xu; Shouqian Sun; Yunhe Pan

    2001-01-01

    While the mobile communication device is developing into the portable information device, it is necessary to design a distributed file-system in such a mobile environment. In order to do it, we must consider the relative shortage of the portable storage and low computation ability of a portable information device as well as unreliable and low-performance networks. By using mobile code

  10. Research and Realization of Mobile IPv6 Protocol Software Based on Vxworks

    Microsoft Academic Search

    Zhang Lin; Li Xiaoping; Zhao Chunxiao; Ji Liangliang

    2009-01-01

    This paper first introduces the principle of mobile IPv6 with the mobile node, communication node and home agent, illuminates the operating process when it moves from the home chain-circuit and designs the module structure that was disassembled into smaller ones for different function. Secondly, IP working process can be logically divided into three subsystem that are home agent subsystem, mobile

  11. Controlled mobility of unmanned aircraft chains to optimize network capacity in realistic communication environments

    NASA Astrophysics Data System (ADS)

    Dixon, Cory

    This dissertation presents a decentralized gradient-based mobility control algorithm for the formation and maintenance of an optimal end-to-end communication chain using a team of unmanned aircraft acting as communication relays. With the use of unmanned aircraft (UA) as communication relays, a common mode of operation is to form a communication relay chain between a lead exploring node (which may be ground based or another UA) and a control station. In this type of operation the lead node is typically deployed to explore (sense) a remote region of interest that is beyond direct radio frequency (RF) communication range, or out of line-of-sight, to the control station. To provide non-line-of-sight service, and extend the communication range of the lead node, unmanned aircraft acting as communication relays are deployed in a convoy fashion behind the lead vehicle to form a cascaded relay chain. The focus of this work is the use of the mobility of a fixed number of relay aircraft to maximize the capacity of a directed communication chain from a source node to a destination node. Local objective functions are presented that use the signal-to-noise-and-interference ratio (SNIR) of neighbor communication links as inputs to maximize the end-to-end capacity of packet-based and repeater-type network chains. An adaptive gradient-based SNIR controller using the local objective function can show significant improvement in the capacity of the communication chain that is not possible with range-based controllers, or static deployment strategies, in RF environments containing unknown localized noise sources and terrain effects. Since the SNIR field is unknown, an online estimate of the SNIR field gradient is formed using methods of Stochastic Approximation from the orbital motion of the aircraft tracking a control point. Flight demonstrations using the Networked Unmanned Aircraft System Command, Control and Communications testbed were conducted to validate the controller presented herein. Results from flight experiments show that mobility of unmanned aircraft, following locally estimated SNIR gradients, can be used to form a locally optimized communication chain by driving the aircraft to locations that improve the end-to-end capacity of the chain over that of a range-based controller or a static deployment algorithm.

  12. An adaptive array antenna for mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Milne, Robert

    1990-01-01

    The design of an adaptive array antenna for land vehicle operation and its performance in an operational satellite system is described. Linear and circularly polarized antenna designs are presented. The acquisition and tracking operation of a satellite is described and the effect on the communications signal is discussed. A number of system requirements are examined that have a major impact on the antenna design. The results of environmental, power handling, and RFI testing are presented and potential problems are identified.

  13. Mobile Telephony: Realising the Dream of Ideal Communication?

    Microsoft Academic Search

    Imar de Vries

    2005-01-01

    Every existing communication technology was once new and full of promise. Upon their\\u000aintroduction, numerous producers and consumers were euphoric about the potential for immediate\\u000aapplication and had fantastic visions of future use. Most of these expectations never really came to fruition, almost every medium has developed in a\\u000adifferent way from what was foreseen, and no medium so far

  14. Communication: Charge, diffusion, and mobility of proteins through nanopores

    PubMed Central

    Muthukumar, M.

    2014-01-01

    Implementation of Einstein's law connecting charge, diffusion coefficient, and mobility to interpret experimental data on proteins from single molecule electrophoresis through nanopores faces serious difficulties. The protein charge and diffusion coefficient, inferred with the Einstein law, can be orders of magnitude smaller than their bare values depending on the electrolyte concentration, pore diameter, chemical nature of the pore wall, and the externally applied voltage. The main contributors to the discrepancies are the coupled dynamics of the protein and its counterion cloud, confinement effects inside the pore, and the protein-pore-surface interaction. We have addressed these ingredients by harking on classical theories of electrophoresis of macroions and hydrodynamics inside pores, and deriving new results for pore-protein interactions. Putting together various components, we present approximate analytical formulas for the effective charge, diffusion coefficient, and mobility of a protein in the context of single molecule electrophoresis experiments. For the omnipresent pore-protein interactions, nonlinear dependence of the velocity of protein on voltage sets in readily and analytical formulas for this effect are presented. The derived formulas enable the determination of the bare charge and size of a protein from the experimentally measured apparent values. PMID:25172998

  15. 14.33 Economics Research and Communication, Spring 2002

    E-print Network

    Ellison, Sara Fisher

    Designed to expose students to the process of conducting independent research in empirical economics and effectively communicating the results of the research. Begins with an econometric analysis of an assigned economic ...

  16. Performance analysis of replication ALOHA for fading mobile communications channels

    NASA Technical Reports Server (NTRS)

    Yan, Tsun-Yee; Clare, Loren P.

    1986-01-01

    This paper describes an ALOHA random access protocol for fading communications channels. A two-state Markov model is used for the channel error process to account for the channel fading memory. The ALOHA protocol is modified to send multiple contiguous copies of a message at each transmission attempt. Both pure and slotted ALOHA channels are considered. The analysis is applicable to fading environments where the channel memory is short compared to the propagation delay. It is shown that smaller delay may be achieved using replications and, in noisy conditions, can also improve throughput.

  17. [Perspectives of mobile communication in the management of diabetics].

    PubMed

    Mlekusch, Wolfgang

    2011-07-01

    Sufficient control of blood glucose levels has been demonstrated to be associated with improved long-term outcome in patients with diabetes. Recent advances in interface technology allow transfer of measurement data to mobile devices, which enables control, multiple access, and storage of these data and virtually links patients and care-giving physicians. The possibility of alerting predefined addressee in case of measurements below or above certain limits offers some sort of security that cannot be obtained by simply penning a single value to a scratchpad. Therefore, treating physicians are able to follow the therapeutic course in an easy and finally time-independent manner. Furthermore, physical contact is not necessary, which may be favorable especially for elderly, sometimes immobile patients. PMID:21858635

  18. 48 CFR 206.302-3 - Industrial mobilization; or engineering, development, or research capability.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Industrial mobilization; or engineering, development, or research capability. 206.302-3...Competition 206.302-3 Industrial mobilization; or engineering, development, or research...

  19. 48 CFR 206.302-3 - Industrial mobilization, engineering, developmental, or research capability, or expert services.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Industrial mobilization, engineering, developmental, or research capability, or expert services...Open Competition 206.302-3 Industrial mobilization, engineering, developmental, or research capability, or expert...

  20. 48 CFR 206.302-3 - Industrial mobilization; or engineering, development, or research capability.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Industrial mobilization; or engineering, development, or research capability. 206.302-3...Competition 206.302-3 Industrial mobilization; or engineering, development, or research...

  1. 48 CFR 206.302-3 - Industrial mobilization, engineering, developmental, or research capability, or expert services.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Industrial mobilization, engineering, developmental, or research capability, or expert services...Open Competition 206.302-3 Industrial mobilization, engineering, developmental, or research capability, or expert...

  2. 48 CFR 206.302-3 - Industrial mobilization; or engineering, development, or research capability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Industrial mobilization; or engineering, development, or research capability. 206.302-3...Competition 206.302-3 Industrial mobilization; or engineering, development, or research...

  3. Mobile virtual communities research: a synthesis of current trends and a look at future perspectives

    Microsoft Academic Search

    Christo El-morr; Jalal Kawash

    2007-01-01

    This article is a synthesis of current research trends in mobile virtual communities. It classifies Mobile Virtual Communities (MVCs) research into appropriate domains, and categorises the different types of virtual communities with respect to three criteria: the degree of virtualisation, the degree of mobility and the degree of cooperation. It also draws some conclusions on future research directions.

  4. An advanced conceptual design study for a mobile satellite communications system

    NASA Astrophysics Data System (ADS)

    Salmasi, A. B.

    It is pointed out that a vast portion of the land mass, and a significant portion of the U.S. population in rural and remote areas, are deprived of most of the advanced telecommunication services offered in metropolitan areas. For the last decade, investigations have been conducted regarding the feasibility to provide telecommunication services throughtout the thinly populated areas with the aid of a geostationary satellite. The considered communication services are related to mobile and thin-route radiotelephony, wideband and narrowband data transmissions, and position location services. The mobile satellite (MSAT) communications system studied could provide a truly national and ubiquitous service. Attention is given to satellite antenna design, an MSAT link design analysis, and analysis results.

  5. Trellis coding with Continuous Phase Modulation (CPM) for satellite-based land-mobile communications

    NASA Technical Reports Server (NTRS)

    1989-01-01

    This volume of the final report summarizes the results of our studies on the satellite-based mobile communications project. It includes: a detailed analysis, design, and simulations of trellis coded, full/partial response CPM signals with/without interleaving over various Rician fading channels; analysis and simulation of computational cutoff rates for coherent, noncoherent, and differential detection of CPM signals; optimization of the complete transmission system; analysis and simulation of power spectrum of the CPM signals; design and development of a class of Doppler frequency shift estimators; design and development of a symbol timing recovery circuit; and breadboard implementation of the transmission system. Studies prove the suitability of the CPM system for mobile communications.

  6. Patient-Provider Communications in Outpatient Clinic Settings: A Clinic-Based Evaluation of Mobile Device and Multimedia Mediated Communications for Patient Education

    PubMed Central

    Schooley, Benjamin; San Nicolas-Rocca, Tonia

    2015-01-01

    Background Many studies have provided evidence of the importance of quality provider-patient communications and have suggested improvements to patient understanding by using video-based instruction. Objective The objective of this study was to understand how mobile information technology assisted video and three-dimensional (3D) image instruction, provided by a health care worker, influences two categories of outcome: (1) patient understanding of information about their condition and detailed medical discharge instructions; and (2) patient perceptions and attitudes toward their health care providers, which included physicians, nurses, and staff. We hypothesize that video and 3D image instruction, provided on a mobile, tablet hardware platform, will improve patient understanding about the diagnostic testing, diagnoses, procedures, medications, and health topics provided to them. We also propose that use of the tablet/video combination will result in improved attitudinal evaluation by patients of their providers and the treatment plan. Methods This study evaluated a hospital clinic-based trial (patient N=284) of video and 3D image instruction, provided on a mobile, tablet hardware platform, and its potential to improve patient understanding about the diagnostic testing, diagnoses, procedures, medications, and health topics provided to them. Results Results showed strong evidence that the system was perceived as helpful for improving patient understanding, and that it improved communication between physicians and patients (P<.001). The advanced age of some patients had no effect on their perceptions of the tablet-based mediation. Physician comments provided useful insights on effective use of such systems in the future. Implications for further development and future research are discussed. Conclusions This study added to the body of evidence that computer-assisted video instructional systems for patients can improve patient understanding of medical instructions from their health care providers and assist with patient compliance. In addition, such systems can be appealing to both patient and provider. PMID:25583145

  7. Performance of equalizers employing a re-training RLS algorithm for digital mobile radio communications

    Microsoft Academic Search

    Takashi Ueda; Hiroshi Suzuki

    1990-01-01

    To improve the transmission performance of high bit-rate digital mobile radio communications in frequency-selective fading environments, a retraining recursive least squares (RT-RLS) algorithm for a decision feedback equalizer (DFE) is proposed. Performance evaluation experiments were carried out with a real-time experimental system that includes a DFE implemented by a single-chip digital signal processor (DSP). Experiments were performed by transmitting 250

  8. Mobile communications experiments on dual-band triangular-patch array antenna using a pseudo satellite

    Microsoft Academic Search

    Toshimitsu TANAKA; J. T. S. Sumantyo; K. Kaneko; D. Ishide; M. Takahashi; K. Ito; S. Yamamoto; A. Miura

    2005-01-01

    A simple satellite-tracking array antenna for mobile satellite communications aimed at ETS-VIII applications has been discussed. The proposed antenna is constituted of triangular patches sequentially rotated by 120°. By successively turning off any one of the patches, it is shown that three beams are created in the conical-cut plane for transmission and reception. Furthermore, the gain can reach more than

  9. New space-time channel models for 2 GHz mobile communications systems with an antenna array

    Microsoft Academic Search

    Ma Ning; Li Ping'an

    2005-01-01

    Two new space-time channel models are introduced for simulating 2 GHz wireless mobile communication systems in outdoor environments. The models combine in reason the power and delay parameters in different environments provided by ITU or 3GPP and the angle parameters generated according to 3GPP\\/3GPP2 joint spatial channel modeling adhoc. The new models can be directly used in the simulations of

  10. DFT Spread Generalized Multi-Carrier Scheme for Broadband Mobile Communications

    Microsoft Academic Search

    Xiaodong Zhang; Mingqi Li; Honglin Hu; Haifeng Wang; Bin Zhou; Xiaohu You

    2006-01-01

    A DFT spread generalized multi-carrier (GMC) based frequency division multiple access (FDMA) scheme, i.e. DFT-S-GMC, is proposed for uplink transmission of wideband mobile communication systems. The scheme achieves spreading gains in the frequency-domain by discrete Fourier transform (DFT), and the frequency division multiplexing (FDM) and FDMA by inverse filter-bank transform (IFBT). By theoretical analysis and simulation results, it is shown

  11. A wide-band propagation model based on UTD for cellular mobile radio communications

    Microsoft Academic Search

    Wei Zhang

    1997-01-01

    The present wide-band propagation model based on uniform geometrical theory of diffraction (UTD) for cellular mobile radio communications includes two major contributions. First, a UTD-based narrow-band channel transfer function containing both the diffracted electric field and the reflection of diffracted electric fields is derived. Not only is it an important element of the wide-band modeling method, but it also leads

  12. Convolutionally interleaved PSK and DPSK trellis codes for shadowed, fast fading mobile satellite communication channels

    Microsoft Academic Search

    A. C. M. Lee; PETER J. McLANE

    1990-01-01

    Using a model from the literature, the performance of convolutionally interleaved phase-shift-keying (PSK) and differential phase-shift-keying (DPSK) trellis codes for digital speech transmission over shadowed mobile satellite communication channels is determined by computer simulation. First the characteristics of fading channels are examined and analyzed in terms of the probability distributions of amplitude, phase, and burst errors. A statistical method, using

  13. Dual-band circularly polarized equilateral triangular-patch array antenna for mobile satellite communications

    Microsoft Academic Search

    J. T. S. Sumantyo; K. Ito; M. Takahashi

    2005-01-01

    The Japan Aerospace Exploration Agency will launch the Engineering Test Satellite VIII (ETS-VIII) in 2006 to support the next generation of mobile satellite communications covering the area of Japan (beam coverage El=38° to 58°). In this paper, a satellite-tracking left-handed circularly polarized triangular-patch array antenna is developed for ground applications. The targeted minimum gain of the antenna is set to

  14. PSK and DPSK trellis codes for fast fading, shadowed mobile satellite communication channels

    Microsoft Academic Search

    P. J. McLane; P. H. Wittke; P. K.-M. Ho; C. Loo

    1988-01-01

    The performance of 8-PSK and 8-DPSK trellis codes is presented for a class of fast fading, land mobile satellite communication channels. The fading model is Rician but, in addition, the line-of-sight path is subjected to a fast lognormal attenuation that represents tree shadowing. The fading parameters used in this study represent the degree of shadowing and are based on measured

  15. Wideband DS-CDMA for next-generation mobile communications systems

    Microsoft Academic Search

    Fumiyuki Adachi; Mamoru Sawahashi; Hirohito Suda

    1998-01-01

    Wideband wireless access based on direct sequence code division multiple access aimed at third-generation mobile communications systems is reviewed. W-CDMA is designed to flexibly offer wideband services which cannot be provided by present cellular systems, with various data rates as high as 2 Mb\\/s. The important concept of W-CDMA is the introduction of intercell asynchronous operation and the pilot channel

  16. Effect of Mobility on Communication Performance in Overloaded One-Dimensional Cellular Networks

    Microsoft Academic Search

    Michihiro Inoue; Noriaki Yoshiura; Yoshikuni Onozato

    2005-01-01

    \\u000a In this paper, we investigate the communication performance of one-dimensional cellular networks from the viewpoint of the\\u000a mobile node’s speed with the simulation method assuming various types of speed distributions. Simulation results are measured\\u000a as blocking probabilities of both new and handoff calls and call completion probability. We can observe the phenomenon that\\u000a blocking probabilities of both new and handoff

  17. UMTS-a path to 3rd generation mobile communications of the 21st century

    Microsoft Academic Search

    Juha Rapeli

    1996-01-01

    UMTS aims at advanced global mobile communication services within the WARC-92 identified frequency bands of 1885-2025 and 2110-2200 MHz. The European Telecommunications Standards Institute (ETSI) is defining UMTS as the European 3rd generation system within the global FPLMTS framework. UMTS standards and ITU recommendations for FPLMTS will be available for the introduction of systems around the year 2000. The GSM

  18. The global footprint of mobile communications: The ecological and economic perspective

    Microsoft Academic Search

    Albrecht Fehske; Gerhard Fettweis; Jens Malmodin; Gergely Biczok

    2011-01-01

    This article quantifies the global carbon footprint of mobile communication systems, and discusses its ecological and economic implications. Using up-to-date data and life cycle assessment models, we predict an increase of CO2 equivalent emissions by a factor of three until 2020 compared to 2007, rising from about 86 to 235 Mto CO2e, suggesting a steeper increase than predicted in the

  19. A description of QUALCOMM Automatic Satellite Position Reporting (QASPR(R)) for mobile communications

    NASA Technical Reports Server (NTRS)

    Ames, William G.

    1990-01-01

    Two satellite position reporting has been introduced into the OmniTRACS mobile satellite communication system. This system significantly improves position reporting reliability and accuracy while simplifying the terminal's hardware. The positioning technique uses the original OmniTRACS TDMA timing signal formats in the forward and return link directions plus an auxiliary, low power forward link signal through a second satellite to derive distance values. The distances are then converted into the mobile terminal's latitude and longitude in real time. A minor augmentation of the spread spectrum profile of the return link allowed the resolution of periodic ambiguities. The system also locates the two satellites in real time with fixed platforms in known locations using identical mobile terminal hardware. Initial accuracies of 1/4 mile have been realized uniformly throughout the USA using a satellite separation of 22 degrees and there are no dead zones, skywaves, or cycle slips as found in terrestrial systems like LORAN-C.

  20. A Survey of Context-Aware Mobile Computing Research

    Microsoft Academic Search

    Guanling Chen; David Kotz

    2000-01-01

    Context-aware computing is a mobile computing paradigm in which applications can discover and take advantage of contextual information (such as user location, time of day, nearby people and devices, and user activity). Since it was proposed about a decade ago, many researchers have studied this topic and built several context-aware applications to demonstrate the usefulness of this new technology. Context-aware

  1. Ku-Band Low-Profile Rx-only and Tx-Rx antennas for Mobile Satellite Communications

    Microsoft Academic Search

    Stefano Vaccaro; F. Tiezzi; M. F. Ru?a; C. D. G. De Oro

    2010-01-01

    This paper presents two different Ku-Band Low-Profile antenna concepts for Mobile Satellite Communications. The antennas are based on low-cost hybrid mechanical-electronic steerable solutions but, while the first one allows a broadband reception of a satellite signal (Receive-only antenna concept), the second one provides transmit and receive functions for a bi-directional communication link between the satellite and the mobile user terminal

  2. Communicating the Importance of Undergraduate Research to Legislators

    ERIC Educational Resources Information Center

    Karukstis, Kerry

    2005-01-01

    The Council on Undergraduate Research (CUR) hosts an annual undergraduate research poster session on Capitol Hill to communicate to the US Congress the importance of undergraduate research and to express thanks for the federal funding of undergraduate research programs. At the "Posters on the Hill" event held on 19 April 2005 in the Rayburn House…

  3. Department of Mobile Communications 2229, route des Cr^etes

    E-print Network

    Gesbert, David

    January 5th , 2012 Prof. Konstantin AVRACHENKOV Prof. Laura COTTATELLUCCI Lorenzo MAGGI Tel : (+33) 4 93.cottatellucci, lorenzo.maggi}@eurecom.fr, 1 EURECOM's research is partially supported by its industrial members: BMW, Lorenzo Maggi Abstract We consider a dynamic multiagent system in which several states succeed each other

  4. Department of Mobile Communications 2229, route des Cr^etes

    E-print Network

    Gesbert, David

    COTTATELLUCCI Lorenzo MAGGI Tel : (+33) 4 93 00 81 00 Fax : (+33) 4 93 00 82 00 Email : k.avrachenkov@sophia.inria.fr, {laura.cottatellucci, lorenzo.maggi}@eurecom.fr, 1 EURECOM's research is partially supported by its, and Cooperation Maintenance Konstantin Avrachenkov, Laura Cottatellucci, Lorenzo Maggi Abstract We deal with multi

  5. Department of Mobile Communications Campus SophiaTech,

    E-print Network

    Gesbert, David

    Access Channels January 17th , 2013 Prof. Konstantin AVRACHENKOV Prof. Laura COTTATELLUCCI Lorenzo MAGGI.cottatellucci, lorenzo.maggi}@eurecom.fr, 1 EURECOM's research is partially supported by its industrial members: BMW, Lorenzo Maggi Abstract We deal with multiple access channels in which the channel coefficients fol- low

  6. Communication and Political Mobilization: Digital Media and the Organization of Anti-Iraq War Demonstrations in the U.S

    Microsoft Academic Search

    W. Lance Bennett; Christian Breunig; Terri Givens

    2008-01-01

    The speed and scale of mobilization in many contemporary protest events may reflect a transformation of movement organizations toward looser ties with members, enabling broader mobilization through the mechanism of dense individual-level political networks. This analysis explores the dynamics of this communication process in the case of U.S. protests against the Iraq war in 2003. We hypothesize that individual activists

  7. Error rate performance of noncoherent detection of duobinary coded MSK and TFM in mobile radio communication systems

    Microsoft Academic Search

    S. Elnoubi; S. C. Gupta

    1981-01-01

    Two continuous phase constant envelope modulation schemes are considered for use in digital mobile radio communication systems. These two schemes, duobinary coded minimum shift keying (MSK) and tamed frequency modulation (TFM), use partial response signaling to achieve efficient power spectrum. Therefore, they are suitable candidates for the application of digital data transmission via mobile radio where spectrum efficiency is an

  8. AN ANALYSIS OF MOBILITY MODEL IN CELLULAR COMMUNICATION SYSTEM USING GAUSSIAN PROBABILITY DENSITY FUNCTION FOR HANDOVER DIRECTION

    Microsoft Academic Search

    S. Phokeewanichkul; B. Homnan

    In this paper, the handover direction based on Gaussian probability density function (Gaussian pdf) is applied for analyzing the mathematical mobility model in cellular communication systems. Since an updated handover direction is related to the speed's range of a mobile station (MS); therefore, the Gaussian pdf should be more suitable for using as the direction pdf at cell boundary than

  9. Handoff with DSP Support: Enabling Seamless Voice Communications across Heterogeneous Telephony Systems on Dual-Mode Mobile Devices

    Microsoft Academic Search

    Hung-yun Hsieh; Chung-wei Li; Hsiao-pu Lin

    2009-01-01

    Many mobile handsets manufactured today are equipped with wireless data modules that can provide users with the alternative to access Internet telephony service for voice communications. Due to the limited coverage area of wireless data service, however, a call established through VoIP service may need to be transferred transparently to mobile telephony service, and vice versa, for maintaining voice call

  10. Edinburgh Research Explorer Static Approximation of MPI Communication Graphs for

    E-print Network

    Millar, Andrew J.

    Edinburgh Research Explorer Static Approximation of MPI Communication Graphs for Optimized Process Approximation of MPI Communication Graphs for Optimized Process Placement'. in LCPC 2014: The 27th International immediately and investigate your claim. Download date: 11. Dec. 2014 #12;Static Approximation of MPI

  11. Aerospace Communications at the NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Miranda, Felix A.

    2006-01-01

    The Communications Division at the NASA Glenn Research Center in Cleveland Ohio has as its charter to provide NASA and the Nation with our expertise and services in innovative communications technologies that address future missions in Aerospace Technology, Spaceflight, Space Science, Earth Science, Life Science and Exploration.

  12. Research and development for international satellite communications in Japan

    Microsoft Academic Search

    A. Ogawa

    1984-01-01

    Major research and development activities for international satellite communications in Japan are introduced. Countermeasures against heavy rainfall-induced deterioration of communications signals, particularly for satellites above the Indian ocean, are addressed. These include results of studies on depolarization compensation for dual-polarized waves, and of a series of propagation experiments for determining the rain attenuation characteristics at 11 GHz for propagation paths

  13. Street Crossing: Observational Research and Developing Health Communication Strategies

    ERIC Educational Resources Information Center

    Mackert, Michael; Lazard, Allison; Wyeth, Ben

    2015-01-01

    Students in communication, and particularly in advertising, are encouraged to value creativity. However, even in programs that value creativity, it can be difficult to encourage creativity in the process of research that guides communication efforts. The project described in this paper--"Street Crossing"--is used in upper-division and…

  14. A View of Oral Communication Activities in Food Science from the Perspective of a Communication Researcher

    ERIC Educational Resources Information Center

    Vrchota, Denise Ann

    2015-01-01

    Food science researchers have pronounced the Institute of Food Technologists Success Skills to be the most important competency mastered by graduates entering the work force. Much of the content and outcomes of the Success Skills pertains to oral communication skills of public speaking and interpersonal and group communication. This qualitative…

  15. Near Field Communication - Research, Teachings and Training

    Microsoft Academic Search

    Juergen Sieck; Volodymyr Brovkov

    2012-01-01

    The development of wireless networks, mobile devices and sensor technology during the past 20 years has continually affected the creation of new applications based on emergent technologies. By combining the advantages of established technologies with these new approaches and furthermore adapting those criteria to different user needs and application scenarios, including the location of users, we are able to extend

  16. Modifying Adoption Research for Mobile Internet Service Adoption: Cross-Disciplinary Interactions

    Microsoft Academic Search

    Per E. Pedersen; Rich Ling

    2003-01-01

    One often meets the argument that the adoption of mobile Internet services is difficult to understand due to a lack of relevant research. However, much research has already been conducted on the adoption of basic mobile and traditional Internet services that are likely to converge into the services provided by the mobile Internet. In this article, we try to categorize

  17. Combining EU Terminology with Communication and Ontology Research Rodolfo Maslias

    E-print Network

    Boyer, Edmond

    Combining EU Terminology with Communication and Ontology Research Rodolfo Maslias Terminology Coordination Unit, European Parliament, Luxembourg Abstract The Terminology Coordination Unit of the European up EU terminology to the science and industry aspects of the field. This presentation will focus

  18. Toward Theory-Based Research in Political Communication.

    ERIC Educational Resources Information Center

    Simon, Adam F.; Iyengar, Shanto

    1996-01-01

    Praises the theoretical and methodological potential of the field of political communication. Calls for greater interaction and cross fertilization among the fields of political science, sociology, economics, and psychology. Briefly discusses relevant research methodologies. (MJP)

  19. All-digital multicarrier demodulators for on-board processing satellites in mobile communication systems

    NASA Astrophysics Data System (ADS)

    Yim, Wan Hung

    Economical operation of future satellite systems for mobile communications can only be fulfilled by using dedicated on-board processing satellites, which would allow both cheap earth terminals and lower space segment costs. With on-board modems and codecs, the up-link and down-link can be optimized separately. An attractive scheme is to use frequency-division multiple access/single chanel per carrier (FDMA/SCPC) on the up-link and time division multiplexing (TDM) on the down-link. This scheme allows mobile terminals to transmit a narrow band, low power signal, resulting in smaller dishes and high power amplifiers (HPA's) with lower output power. On the up-link, there are hundreds to thousands of FDM channels to be demodulated on-board. The most promising approach is the use of all-digital multicarrier demodulators (MCD's), where analog and digital hardware are efficiently shared among channels, and digital signal processing (DSP) is used at an early stage to take advantage of very large scale integration (VLSI) implementation. A MCD consists of a channellizer for separation of frequency division multiplexing (FDM) channels, followed by individual modulators for each channel. Major research areas in MCD's are in multirate DSP, and the optimal estimation for synchronization, which form the basis of the thesis. Complex signal theories are central to the development of structured approaches for the sampling and processing of bandpass signals, which are the foundations in both channellizer and demodulator design. In multirate DSP, polyphase theories replace many ad-hoc, tedious and error-prone design procedures. For example, a polyphase-matrix deep space network frequency and timing system (DFT) channellizer includes all efficient filter bank techniques as special cases. Also, a polyphase-lattice filter is derived, not only for sampling rate conversion, but also capable of sampling phase variation, which is required for symbol timing adjustment in all-digital demodulators. In modulation schemes, a systematic survey is reported, based on two expressions that includes all formats in linear and constant envelope modulation. In synchronization techniques, classifications according to the criterion of statistical optimization, the data dependecy, and the method of parameter extraction, reflect the inherent complexity and performance of numerous existing algorithms. The designs of two new algorithms are presented: a differential decision frequency error detector that is simple and fast; a dual-comb-filter frequency/timing error detector that is targeted at VLSI implementation. The real-time implementation of a complete 4 x 16 kb/s MCD for the T-SAT project is described in detail, which proved many of the structured design concepts developed in this thesis. The requirements of software tools for various levels of simulation in multirate DSP and communications are analyzed. This led to the implementation of a data-flow oriented simulation system, which was used in all research work in the thesis.

  20. The Effects of International Mobility on European Researchers: Comparing Intra-EU and U.S. Mobility

    ERIC Educational Resources Information Center

    Veugelers, Reinhilde; Van Bouwel, Linda

    2015-01-01

    Using econometric analysis on survey data from European-born and European-educated researchers who are internationally mobile after their PhD within Europe or to the United States, we find significant positive effects from international mobility on scientific productivity, as well as several other positive career development effects. European…

  1. Review of Computer Mediated Communication Research for Education

    ERIC Educational Resources Information Center

    Luppicini, Rocci

    2007-01-01

    This research review examines recent developments in computer-mediated communication (CMC) research for educational applications. The review draws on 170 recent research articles selected from 78 journals representing a wide range of disciplines. The review focuses on peer-reviewed empirical studies, but is open to a variety of methodologies. The…

  2. The Emerging Information and Communications Technology Educational Research Forum.

    ERIC Educational Resources Information Center

    Davis, Niki

    1999-01-01

    Describes the development of the ICT (Information and Communications Technology) Educational Research Forum (ERF), which aims to fulfill some of the needs of the education profession to engage with research in the field of ICT, focusing on the ERF design principles; ERF web site content and structure; evaluation and research of the ERF; and future…

  3. Starting them Early: Incorporating Communication Training into Undergraduate Research Internships

    NASA Astrophysics Data System (ADS)

    Bartel, B. A.; Morris, A. R.; Charlevoix, D.

    2014-12-01

    In order to truly broaden the impact of our scientific community, effective communication should be taught alongside research skills to developing scientists. In the summer of 2014, we incorporated an informal communications course into the 10th year of UNAVCO's Research Experiences in Solid Earth Science for Students (RESESS), a year-long internship program centered around an 11-week intensive summer research experience. The goals of the newly designed course included giving students the tools they need to make a broader impact with their science, starting now; improving the students' confidence in public speaking and using social media for outreach; and giving students the tools they need to apply for jobs or graduate school. Specifically, the course included teaching of professional communication skills, such as e-mail and phone etiquette, resume and CV tailoring, and interview techniques, and public communications skills, such as crafting and simplifying messages, visual communication for the public, and public speaking. Student interns were encouraged to step back from the details of their research projects to put their work into a big-picture context relevant to the public and to policy makers. The course benefited from input and/or participation from UNAVCO Education and Community Engagement staff, engineering and managerial staff, and graduate student interns outside the RESESS program, and University of Colorado research and communications mentors already involved in RESESS. As the summer program is already packed with research and skill development, one major challenge was fitting in teaching these communications skills amongst many other obligations: a GRE course, a peer-focused scientific communications course, a computing course, and, of course, research. Can we do it all? This presentation will provide an overview of the course planning, articulation of course goals, and execution challenges and successes. We will present our lessons learned from summer 2014 as well as feedback from both student interns and UNAVCO staff who helped support the course.

  4. Research Directions in Family Communication: Proceedings of the Family Communication Research Conference (Evanston, Illinois, September 6-8, 1984).

    ERIC Educational Resources Information Center

    Yerby, Janet, Ed.

    In a conference focusing on issues in research methods, family theory, and family therapy as they relate to family communication and on future research needs, this document consists of papers presented by the 12 participants. Specific titles and speakers were as follows: "Kinship Relationships," by Mary Anne Fitzpatrick; "Research Potentials in…

  5. Session Management in Mobile Data Communications KTH/UPM Manuel Sanchez Cabas

    E-print Network

    Maguire Jr., Gerald Q.

    Sanchez Cabas Preface This Master Thesis work was done at Ericsson Radio Systems, Core Unit of Tech is an applied research organization within Ericsson working with mobile networks and systems technology in order terminals and they want to be provided with access to network resources in any place at any given point

  6. Mobile Phone Technology: A New Paradigm for the Prevention, Treatment, and Research of the Non-sheltered “Street” Homeless?

    PubMed Central

    2010-01-01

    Individuals experiencing homelessness have disproportionately high rates of health problems. Those who perceive themselves as having greater access to their social support networks have better physical and mental health outcomes as well as lower rates of victimization. Mobile phones offer a connection to others without the physical constraints of landlines and, therefore, may make communication (e.g., access to one’s social support networks) more feasible for homeless individuals. This, in turn, could lead toward better health outcomes. This exploratory study examined mobile phone possession and use among a sample of 100 homeless men and women who do not use the shelter system in Philadelphia, PA. Interviews were comprised of the Homeless Supplement to the Diagnostic Interview Schedule, a technology module created for this investigation, and the substance use and psychiatric sections of the Addiction Severity Index. Almost half (44%) of the sample had a mobile phone. In the past 30 days, 100% of those with mobile phones placed or received a call, over half (61%) sent or received a text message, and one fifth (20%) accessed the Internet via their mobile phone. Participants possessed and used mobile phones to increase their sense of safety, responsibility (employment, stable housing, personal business, and sobriety or “clean time”), and social connectedness. Mobile phones could potentially be used by public health/health care providers to disseminate information to the street homeless, to enhance communication between the street homeless and providers, and to increase access for the street homeless to prevention, intervention, and aftercare services. Finally, this technology could also be used by researchers to collect data with this transient population. PMID:20397058

  7. Scientific Mobility and International Research Networks: Trends and Policy Tools for Promoting Research Excellence and Capacity Building

    ERIC Educational Resources Information Center

    Jacob, Merle; Meek, V. Lynn

    2013-01-01

    One of the ways in which globalization is manifesting itself in higher education and research is through the increasing importance and emphasis on scientific mobility. This article seeks to provide an overview and analysis of current trends and policy tools for promoting mobility. The article argues that the mobility of scientific labour is an…

  8. A study of land mobile satellite communication systems in the geostationary platform area

    NASA Astrophysics Data System (ADS)

    Kohmura, M.; Otsu, Y.; Miyasaka, K.; Uda, H.

    The design concept of a land mobile communication (LMC) network for Japan, based on a multiple-beam GEO platform to be launched early in the 21st century, is discussed. The market for LMC services is assessed; the LMC frequency-reuse requirements for the major Japanese metropolitan areas are estimated; and particular attention is given to recent advances in multibeam antennas and transponders, LMC network configurations, LMC terminals, propagation and modulation coding, and the possible inclusion of hardware for mm-wave communication and direct broadcasting on the platform. The payload weight and power requirements for a dedicated LMC platform are estimated as 1100 kg and 2.5 kW; the values for the multiple-use platform are 2000 kg and 10-13 kW, respectively.

  9. Using a Communication Model to Collect Measurement Data through Mobile Devices

    PubMed Central

    Bravo, José; Villarreal, Vladimir; Hervás, Ramón; Urzaiz, Gabriel

    2012-01-01

    Wireless systems and services have undergone remarkable development since the first mobile phone system was introduced in the early 1980s. The use of sensors in an Ambient Intelligence approach is a great solution in a medical environment. We define a communication architecture to facilitate the information transfer between all connected devices. This model is based in layers to allow the collection of measurement data to be used in our framework monitoring architecture. An overlay-based solution is built between network elements in order to provide an efficient and highly functional communication platform that allows the connection of a wide variety of devices and technologies, and serves also to perform additional functions such as the possibility to perform some processing in the network that may help to improve overall performance. PMID:23012542

  10. A spread-spectrum modem using constant envelope BPSK for a mobile satellite communications terminal

    NASA Technical Reports Server (NTRS)

    Iizuka, N.; Yamashita, A.; Takenaka, S.; Morikawa, E.; Ikegami, T.

    1990-01-01

    This paper describes a 5-kilobit/s spread spectrum modem with a 1.275 mega-Hz chip rate for mobile satellite communications. We used a Viterbi decoder with a coding gain of 7.8 dB at a BER of 10(exp -5) to decrease the required receiver power. This reduces the cost of communication services. The spread spectrum technique makes the modem immune to terrestrial radio signals and keeps it from causing interference in terrestrial radio systems. A class C power amplifier reduces the modem's power consumption. To avoid nonlinear distortion caused by the amplifier, the envelope of the input signal is kept constant by adding quadrature channel signal to the BPSK signal. To simulate the worst case, we measured the modem's output spectrum using a limiting amplifier instead of the class C amplifier, and found that 99 percent of the spectral power was confined to the specified 2.55 mega-Hz bandwidth.

  11. From Research to Practice: Communications for Social Change

    ERIC Educational Resources Information Center

    Davey, Lynn

    2009-01-01

    What happens when the research inquiry is complete and has determined which reframes will be most successful in improving public understanding of an issue and advancing policy goals? Simple dissemination of research findings is not sufficient to improve the communications capacity of the field. The author explains how cognitive science and social…

  12. A Graduate School and a Research Center in Communications

    E-print Network

    Cengarle, María Victoria

    A Graduate School and a Research Center in Communications Systems Jan REMBOWSKI International And System Analysis · OpenAirInterface Radio Platforms #12;11/07/2012 p 18 THE TELECOM PARIS RESEARCH DEPARTMENTS · SYSTEMS ON CHIP SystemonaChip Design, Design space exploration, Support for refinement towards

  13. PROCEEDINGS OF THE ROTTERDAM MOBILITY RESEARCH CONFERENCE (ROTTERDAM, THE NETHERLANDS, AUGUST 3-7, 1964).

    ERIC Educational Resources Information Center

    CLARK, LESLIE L.; AND OTHERS

    THESE PROCEEDINGS WERE PREPARED FROM THE MOBILITY RESEARCH CONFERENCE HELD IN ROTTERDAM, THE NETHERLANDS, AUGUST 3-7, 1964. PROGRESS REPORTS ARE GIVEN ON THE FOLLOWING--(1) ULTRASONIC MOBILITY AID, (2) ULTRASONIC GUIDANCE SYSTEM, (3) ELEKTROFTALM MOBILITY AID, (4) PASSIVE ENVIRONMENT SENSORS, (5) AMBIENT-LIGHT OBJECT DETECTOR, (6) TRAVEL PATH…

  14. Computer Science and Communications Research Unit

    E-print Network

    van der Torre, Leon

    . . . . . . . . . . . . . . . . . . . . . . . . . 22 4.1.1 European funding projects . . . . . . . . . . . . . . . 22 4.1.2 FNR Projects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4 Projects and Grants in 2010 13 4.1 Research projects

  15. The ELLIPSO (tm) system: Elliptical low orbits for mobile communications and other optimum system elements

    NASA Astrophysics Data System (ADS)

    Castiel, David

    1991-09-01

    On 5 Nov. 1990, Ellipsat filed with the FCC the first application to provide voice communication services via low earth orbiting (LEO) satellites. The proposed system, ELLIPSO, aims at achieving end-user costs comparable to those in the cellular industry. On 3 Jun. 1991 Ellipsat filed for the second complement of its system. Ellipsat was also the first company to propose combined position determination and mobile voice services via low-earth orbiting satellites. Ellipsat is still the only proponent of elliptical orbits for any commercial system in the United States. ELLIPSO uses a spectrum efficient combination of FDMA and CDMA techniques. Ellipsat's strategy is to tailor required capacity to user demand, reduce initial system costs and investment risks, and allow the provision of services at affordable end-user prices. ELLIPSO offers optimum features in all the components of its system, elliptical orbits, small satellites, integrated protocol and signalling system, integrated end-user electronics, novel marketing approach based on the cooperation with the tenets of mobile communications, end-user costs that are affordable, and a low risk approach as deployment is tailored to the growth of its customer base. The efficient design of the ELLIPSO constellation and system allows estimated end-user costs in the $.50 per minute range, five to six times less than any other system of comparable capability.

  16. Mobile Applications for Participation at the Shopping Mall: Content Analysis and Usability for Persons with Physical Disabilities and Communication or Cognitive Limitations

    PubMed Central

    Auger, Claudine; Leduc, Emilie; Labbé, Delphine; Guay, Cassioppée; Fillion, Brigitte; Bottari, Carolina; Swaine, Bonnie

    2014-01-01

    The aim of this exploratory study was to determine the important features in content and usability of existing mobile applications evaluating environmental barriers and facilitators (EBF) to participation for persons with physical disabilities presenting mild communication or cognitive limitations. A rigorous process based on a user-centered design approach led to the identification of two relevant mobile applications to evaluate the EBF. An accessibility expert, the research team as well as five users then tested the mobile applications in a shopping mall. A thematic content analysis of the research team’s and users’ comments established 10 categories of key features that adequately respond to the needs of the clientele targeted in this study. In terms of content, granularity and contextualization of the information provided were considered important. With respect to usability, relevant features were place finding, rating system, presentation of results, compatibility, user-friendliness, aesthetics, credibility of the information as well as connectivity/interactiveness. The research team and the users agreed on some aspects such as aesthetics, but had different perspectives on features such as the rating system or the connectivity/interactiveness of the application. The users proposed new features suggesting that the existing mobile applications did not correspond to all their needs. PMID:25513999

  17. Content Analysis as a Foundation for Programmatic Research in Communication

    PubMed Central

    Slater, Michael D.

    2013-01-01

    Previous arguments that content analyses provide the descriptive foundation for media effects research (McLeod & Reeves, 1980) are extended to include that content analyses can provide a sound and useful foundation for programmatic research by individual communication scientists. I discuss examples from my own work and from that of colleagues in communication and related disciplines. Use of messages sampled and coded in a content analysis in combination with survey data sets or as stimuli in experiments are highlighted. The particular potential for employing larger numbers of randomly sampled messages in experimental designs, and, with use of appropriate statistical methods, being able to generalize to populations of messages, is described. PMID:23914276

  18. Small-Scale Design Experiments as Working Space for Larger Mobile Communication Challenges

    ERIC Educational Resources Information Center

    Lowe, Sarah; Stuedahl, Dagny

    2014-01-01

    In this paper, a design experiment using Instagram as a cultural probe is submitted as a method for analyzing the challenges that arise when considering the implementation of social media within a distributed communication space. It outlines how small, iterative investigations can reveal deeper research questions relevant to the education of…

  19. Recent research and development on laser communication in Israel

    NASA Astrophysics Data System (ADS)

    Arnon, Shlomi

    2004-10-01

    Research and development of laser communication in Israel encompasses many different areas including inter-satellite communication, terrestrial communication and indoor communication. The R&D activity is mainly being carried out in two sectors: academia and industry. Additionally there is some activity in start-up companies. In this paper, I survey several areas of R&D activity to which Israel has contributed. 1) Broadband Laser Inter-satellite Link (BLISL). This is a joint Israeli-German five-year applied research project supported by the DIP foundation. Its objective is to develop technologies and know-how for broadband optical inter-satellite communication terminals for applications on small satellites in LEO/MEO constellations. 2) Urban optical wireless systems. This area has received much attention in academia. The main task is to quantify atmospheric effects on system performance and to apply this information in industry. 3) Short range communication for indoor applications. The main aim here is to develop adaptive techniques 4) Agile laser scanning/steering. This technology is essential for the next generation of optical wireless systems. 5) Atmospheric probing. We discuss a new concept for atmospheric probing known as firefly clustering.

  20. AMALi - the Airborne Mobile Aerosol Lidar for Arctic research

    NASA Astrophysics Data System (ADS)

    Stachlewska, I. S.; Neuber, R.; Lampert, A.; Ritter, C.; Wehrle, G.

    2009-09-01

    The Airborne Mobile Aerosol Lidar (AMALi) is an instrument developed at the Alfred Wegener Institute for Polar and Marine Research for a trouble-free operation under the challenging weather conditions at the Earth's polar regions. Since 2003 the AMALi has been successfully deployed for measurements in the ground-based installation and the zenith- or nadir-aiming airborne configurations during several scientific campaigns in the Arctic. The lidar provides profiles of the total backscatter at two wavelengths, from which aerosol and cloud properties are derived. It measures also the linear depolarization of the backscattered return, allowing for the discrimination of thermodynamic cloud phase and the identification of the presence of non-spherical aerosol particles. This paper presents the capability characteristics and performance of the past and present state of the AMALi system, as well as discusses the ground-based and airborne evaluation schemes applied to invert the data.

  1. MoLeNET Mobile Learning Conference 2009: Research Papers

    ERIC Educational Resources Information Center

    Guy Parker, Ed.

    2010-01-01

    The Mobile Learning Network (MoLeNET) is a unique collaborative approach to encouraging, supporting, expanding and promoting mobile learning, primarily in English post-14 education and training, via supported shared cost mobile learning projects. Collaboration at national level involves participating institutions and the Learning and Skills…

  2. Mobile Payment Market and Research - Past, Present and Future

    Microsoft Academic Search

    Tomi Dahlberg; Niina Mallat

    2006-01-01

    The mobile payment market is currently under transition with a history of numerous tried and failed solutions and a future of promising but yet uncertain possibilities with contactless RFID and other new potential technologies. At this point of the development we take a look at the current state of the mobile payment market, review prior literature on mobile payment services,

  3. Research of Improved GA in WSN Mobile Agent Routing Algorithm

    Microsoft Academic Search

    Wang Jinghua; Guan Tingting; He Huan; Chen Yuanyuan

    2009-01-01

    Mobile agent which has the features of migration and autonomy can be used in Wireless Sensor Network (WSN). An improved Genetic Algorithm (GA) is proposed to use in mobile agent-based routing algorithm to calculate the best routing for mobile agent's migration in WSN. By improving the arithmetic operators, the improved GA can find the best routing, and optimize the performance

  4. A survey of mobility models for ad hoc network research

    Microsoft Academic Search

    Tracy Camp; Jeff Boleng; Vanessa Davies

    2002-01-01

    In the performance evaluation of a protocol for an ad hoc network, the protocol should be tested under realistic conditions including, but not limited to, a sensible transmission range, limited buffer space for the storage of messages, representative data traffic models, and realistic movements of the mobile users (i.e., a mobility model). This paper is a survey of mobility models

  5. Understanding the behavior of mobile data services consumers

    Microsoft Academic Search

    Se-joon Hong; James Y. L. Thong; Jae-Yun Moon; Kar Yan Tam

    2008-01-01

    Due to rapid advances in the Internet and wireless technologies, a ubiquitous computing world is becoming a reality in the form of mobile computing. At the center of this phenomenon is mobile data services which arise from the convergence of advanced mobile communication technologies with data services. Despite the rapid growth in mobile data services, research into consumers’ usage behavior

  6. Modeling the Interaction of Users and Mobile Payment System: Conceptual Framework

    Microsoft Academic Search

    Dong-Hee Shin

    2010-01-01

    The growing interest in mobile commerce and the high penetration rate of mobile communication service are expected to provide mobile operators with a new and great business opportunity, the mobile payment. This study proposes a research model that examines the factors that determine consumer acceptance of mobile payment system. To achieve this goal, it employed the technology acceptance model (TAM),

  7. IEEE Wireless Communications October 20022 1070-9916/02/$17.00 2002 IEEE Wireless Internet

    E-print Network

    Kwon, Taekyoung

    network CN Wireless Internet access has gained significant attention as wireless/mobile communications in the convergence of the IP-based Internet and mobile cellular networks. INTRODUCTION Recently, mobility support for Internet access has created significant interest among researchers as wireless/mobile communications

  8. Mobility management in mobile IP

    Microsoft Academic Search

    Sirisha Medidi; Forouzan Golshani

    2002-01-01

    There is an emerging interest in integrating mobile wireless communication with the Internet based on the Ipv6 technology. Many issues introduced by the mobility of users arise when such an integration is attempted. This paper addresses the problem of mobility management, i.e., that of tracking the current IP addresses of mobile terminals and sustaining active IP connections as mobiles move.

  9. Communication, Sensing, and Resource Allocation Research at Ohio State

    E-print Network

    Schniter, Philip

    Communication, Sensing, and Resource Allocation Research at Ohio State Prof. Phil Schniter OHIO. Labs) March 23, 2010 Phil Schniter (Ohio State) Comm, Sensing, and Resource Allocation March 23, 2010 1 2005 (MIT Lincoln Labs) and many M.S. students! Phil Schniter (Ohio State) Comm, Sensing, and Resource

  10. One-Tailed F-Tests in Communication Research.

    ERIC Educational Resources Information Center

    Levine, Timothy R.; Banas, John

    2002-01-01

    Documents the recent use of one-tailed F-tests in communication journals, and examines the arguments both for and against their use. Examines the use of these tests within the broader unresolved controversy surrounding the use of one-tailed tests. Recommends that future researchers should most often avoid one-tailed Fs, and generally exercise…

  11. The "New" Rhetoric of Mass Communication Research: A Longer View.

    ERIC Educational Resources Information Center

    Lang, Kurt; Lang, Gladys Engel

    1983-01-01

    Concludes that although the new rhetoric may serve as a reminder that communication studies are more than simple effects research, the ferment produced by a highly politicized debate--if it successfully masquerades as scholarly controversy--can become intellectually self-limiting and sterile. (PD)

  12. Critical Communicative Methodology: Including Vulnerable Voices in Research through Dialogue

    ERIC Educational Resources Information Center

    Puigvert, Lidia; Christou, Miranda; Holford, John

    2012-01-01

    This article describes how Critical Communicative Methodology (CCM) has been used successfully to analyse educational inequalities in ways that generate real transformation towards social justice. We begin by arguing that educational research today should employ new methodological approaches that can ensure the inclusion of different voices in…

  13. A Rules Approach as a Supplement to Organizational Communication Research.

    ERIC Educational Resources Information Center

    Laird, Angela

    This paper argues that communication researchers could benefit from incorporating a rules approach as a supplement to more traditional methods of organizational analysis. Two major flaws in the methodology of traditional organizational analysis are noted: failing to account for actor or participant meanings--how the actor interprets relationships,…

  14. Making Numbers Matter: Present and Future Research in Risk Communication

    ERIC Educational Resources Information Center

    Fagerlin, Angela; Ubel, Peter A.; Smith, Dylan M.; Zikmund-Fisher, Brian J.

    2007-01-01

    Objective: To summarize existing research on individual numeracy and methods for presenting risk information to patients. Methods: We selectively retrieved articles from MEDLINE and the "Social Sciences Citation Index". Results: Many Americans have low numeracy skills, a deficit that impedes effective health care. Approaches to risk communication

  15. Transforming Violent Selves through Reflection in Critical Communicative Research

    ERIC Educational Resources Information Center

    Flecha, Ainhoa; Pulido, Cristina; Christou, Miranda

    2011-01-01

    Currently, teenagers are being socialized into a world of violent realities, not only through social interaction but also through interaction via the media, especially via the Internet. Research conducted using the critical communicative methodology has shown that this methodology helps young people to reflect critically about their violent…

  16. Communicative Language Testing: Current Issues and Future Research

    ERIC Educational Resources Information Center

    Harding, Luke

    2014-01-01

    This article discusses a range of current issues and future research possibilities in Communicative Language Testing (CLT) using, as its departure point, the key questions which emerged during the CLT symposium at the 2010 Language Testing Forum. The article begins with a summary of the 2010 symposium discussion in which three main issues related…

  17. Original Research Communication Prion Protein Expression and Functional Importance in

    E-print Network

    Paris-Sud XI, Université de

    1 1 Original Research Communication Prion Protein Expression and Functional Importance illustrations: 7 Color illustrations: 2 (online 2) Page 1 of 48 Antioxidants&RedoxSignaling PrionProtein prion protein (PrPC ), a GPI-anchored glycoprotein, which we reported to be highly expressed in human

  18. RESEARCH COMMUNICATION Evidence that Swi/Snf directly

    E-print Network

    Winston, Fred

    RESEARCH COMMUNICATION Evidence that Swi/Snf directly represses transcription in S. cerevisiae 02115, USA Many studies have established that the Swi/Snf family of chromatin-remodeling complexes transcription. We now pre- sent chromatin immunoprecipitation evidence that the Swi/Snf complex of Saccharomyces

  19. Z .Developmental Brain Research 111 1998 143146 Short communication

    E-print Network

    Fernald, Russell

    similarities exist between am- phibian and teleost retinal development, specific studies of the role of cell age for analysis. Embryos were collected and incubated at 308C. At this temperature, retinal cellZ .Developmental Brain Research 111 1998 143­146 Short communication Cell death precedes rod

  20. RESEARCH COMMUNICATION pha-4, an HNF-3 homolog,

    E-print Network

    Mango, Susan

    RESEARCH COMMUNICATION pha-4, an HNF-3 homolog, specifies pharyngeal organ identity the development of cells unrelated to one another by cell type or ancestry. Here we show that the pha-4 locus establishes organ identity for the Caenorhabditis elegans pharynx. In pha-4 mutants, pharyngeal cells

  1. An Infrared Network for Mobile Computers

    Microsoft Academic Search

    Norman Adams; Bill N. Schilit; Michael M. Tso; Roy Want

    1993-01-01

    The PARCTAB infrared network provides a flexible infrastructure for research into wireless mobile computing. The network consists of a collection of room-sized cells each wired with a base station transceiver. Mobile computers communicate with transceivers through a carrier sense multiple access (CSMA) protocol and act as terminals for applications executing on remote hosts. Each mobile computer is represented by a

  2. Research of STBC in free space optical communications system

    NASA Astrophysics Data System (ADS)

    Deng, Tianping; Peng, Kai; Lu, Yimin

    2009-12-01

    Free Space Optical (FSO) communication is a communication pattern in which laser is used as the information carrier in atmosphere environment. FSO system has been widely applied in the fields of satellite communication and ground sight distance communication, with a promising application prospect and tremendous market potential. And space-time processing (using multiple antennas) is now recognized as a key to achieving reliable high data rate wireless communications and is being incorporated into the physical layer of many wireless standards. In this letter, error rate performance for space-time block coding (STBC) in FSO communication systems with direct detection operating over strong atmospheric turbulence channels is analyzed. The purpose of the paper is: (i) to determine the channel capacity of FSO system in the presence of atmospheric turbulence, (ii) to see how much this limit can be approached using the best known STBC techniques. In this paper, we use mathematics tool to establish the channel model of FSO system, and then apply the STBC to the FSO system, research the decoding method and simulate the performance using MATLAB tools. The mathematics analysis and simulation results show the great application expectation of STBC in the OOK channel of the FSO system.

  3. Measured path loss and multipath propagation characteristics in UHF and microwave frequency bands for urban mobile communications

    Microsoft Academic Search

    Yasuhiro Oda; Reiko Tsuchihashi; Kouichi Tsunekawa; Masaharu Hata

    2001-01-01

    This paper presents the frequency dependence of propagation loss and multipath propagation characteristics for urban mobile communications based on measurement results in Japanese urban areas. Path loss in reference frequencies from 457.2 MHz to 15.45 GHz increases according to the free space propagation power law in terms of frequency dependence for both macrocell and microcell environments. The standard deviation of

  4. 21st Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications A QoS Tracking Algorithm for

    E-print Network

    Valaee, Shahrokh

    21st Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications A QoS each node in order to provide QoS differ entiation gaps among AC queues. It has been shown nodes. Briefly, for QoS differentiation, many schemes such as [5, 10, 1 1] were proposed to use

  5. Edgar Nett Mobile Computer Communication SS'14 22 Using Spreading for all signals of a frequency band

    E-print Network

    Mobile Computer Communication SS'14 23 DSSS (Direct Sequence Spread Spectrum) I Product of stream'14 24 DSSS (Direct Sequence Spread Spectrum) II X user data chipping sequence modulator radio carrier to using FDM 2 2 2 2 2 frequency channel quality 1 spread spectrum spread spectrum channels #12;Edgar Nett

  6. Competition between regional standards and the success and failure of firms in the world-wide mobile communication market

    Microsoft Academic Search

    Jefrey L Funk

    1998-01-01

    This paper describes the evolution of competition in the world-wide mobile communication market. Most firms have succeeded with products (infrastructure and phones) and phone services that are based on domestic standards, while relatively few firms (Ericsson, Motorola, and Nokia) have succeeded in the development of infrastructure and phones that are based on non-domestic standards. The lack of firms which have

  7. Near-toll-quality real-time speech coding at 4.8 kbit/s for mobile satellite communications

    NASA Astrophysics Data System (ADS)

    Tzeng, F. F.

    This paper addresses the design issues of a near-toll-quality 4.8-kbit/s speech coder for real-time mobile satellite communications applications. Specifically, methods for coder performance improvement, computational complexity reduction, and memory complexity reduction are presented. Considerations for coder operation under noisy, fading channels are also discussed.

  8. The Complexity of Social Mobilization in Health Communication: Top-Down and Bottom-Up Experiences in Polio Eradication

    Microsoft Academic Search

    Rafael Obregón; Silvio Waisbord

    2010-01-01

    The Polio Eradication Initiative (PEI) has been one of the most ambitious global health efforts in recent times. Social mobilization (SM) has been a strategic component of the PEI. Yet, a close-up analysis of SM dynamics seems to be lacking in the health communication literature. We examine critical aspects of the PEI experience in an attempt to move from dominant

  9. Proc. of IEEE Wireless Communications and Networking Conference (WCNC), March 2003 Mobility Patterns in Microcellular Wireless Networks

    E-print Network

    Peha, Jon M.

    Proc. of IEEE Wireless Communications and Networking Conference (WCNC), March 2003 Mobility Patterns in Microcellular Wireless Networks Suttipong Thajchayapong and Jon M. Peha Department- cellular wireless networks, based on measurements from the 802.11-based system that blankets the Carnegie

  10. Performance Analysis of Maximal Ratio Combining and Comparison with Optimum Combining for Mobile Radio Communications with Cochannel Interference

    Microsoft Academic Search

    A. Shah; A. M. Haimovich

    2000-01-01

    The performance of maximal ratio combining for space diversity reception in digital cellular mobile radio systems is studied for communications in the presence of multiple cochannel interference (CCI) sources and is compared to optimum com- bining. The main contribution of the paper is that the analysis accounts for fading of the signal of interest (SOI) as well as the cochannel

  11. Performance of multi-level QAM with maximal ratio combining space diversity for land mobile radio communications

    Microsoft Academic Search

    S. Sampei; T. Sunaga

    1990-01-01

    A novel type of space diversity with maximal ratio combining for multilevel quadrature amplitude modulation (QAM) in land mobile communications to improve transmission performance is proposed. In order to realize maximal ratio combining space diversity for QAM, a novel type of diversity combining method using a pilot symbol insertion type fading estimator is applied. The proposed diversity combining is carried

  12. JOURNAL OF COMMUNICATIONS AND NETWORKS, ? 1 Application of Network Coding to IEEE 802.16j Mobile

    E-print Network

    Jang, Ju-Wook

    IEEE 802.16j draft standard does not allow broadcast needed for network coding. We devise a new frameJOURNAL OF COMMUNICATIONS AND NETWORKS, ? 1 Application of Network Coding to IEEE 802.16j Mobile Multi-hop Relay (MMR) Network for Throughput Enhancement Kyungjun Lee, Wonjin Sung, Ju Wook Jang

  13. 2172 IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 49, NO. 12, DECEMBER 2001 Estimation of Mobile Speed and Average Received

    E-print Network

    Cox, Donald C.

    2172 IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 49, NO. 12, DECEMBER 2001 Estimation of Mobile Speed and average power estimates are also used to detect the corner effect in urban cellular systems to improve handoff performance and reduce the call dropping rate. Index Terms--Speed estimation, wavelets, wireless

  14. SUBMITTED TO IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 1 Stochastic Geometric Analysis of User Mobility in

    E-print Network

    Liang, Ben

    SUBMITTED TO IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 1 Stochastic Geometric Analysis Member, IEEE Abstract--Horizontal and vertical handoffs are important ramifications of user mobility in different tiers. We derive theoretical expressions for the rates of all handoff types experienced

  15. Informing the public about information and participation strategies in the siting of mobile communication base stations: an experimental study

    Microsoft Academic Search

    Peter M. Wiedemann; Holger Schütz

    2008-01-01

    Informing the public and ensuring their participation are considered important characteristics for a successful siting of mobile communication base stations. However, there is only sparse empirical evidence for this presumption. In particular, nothing is known about whether informing people that a siting decision is based on public information and participation activities has any positive effects. The experimental study presented here

  16. Glacier Research Digital Science Communication Evolution 1996-2014

    NASA Astrophysics Data System (ADS)

    Pelto, M. S.

    2014-12-01

    This talk will focus on the changes in communicating science in the last 20 years from the perspective of the same research project. Essentially the rapid innovation in online communication requires the scientist learning and utilizing a new platform of communication each year. To maintain relevant visibility and ongoing research activities requires finding synergy between the two. I will discuss how digital communication has inspired my research efforts. This talk will also examine overall visitation and media impact metrics over this period. From developing a highly visible glacier research web page in 1996, to writing more than 400 blog posts since 2008, and in 2014 utilizing a videographer and illustration artist in the field, this is the story of one scientist's digital communication-media evolution. The three main observations are that: 1) Overall visitation has not expanded as rapidly in the last decade. 2) Contact and cooperation with colleagues has expanded quite rapidly since 2008. 3) Media impact peaked in 2005, but is nearing that peak again. The key factors in visibility and media impact for a "small market" research institution/project has been providing timely and detailed content to collaborative sites, such as RealClimate, BAMS State of the Climate, Climate Denial Crock of the Week, and Skeptical Science that can then be repurposed by the media. A review of the visitor metrics to the digital glacier sites I have maintained from 1996-2014 indicate visibility of each platform has a similar growth curve, transitioning to a plateau, but overall visitation does not increase in kind with the increase in number of platforms. Media metrics is more event driven and does not follow the visitor metric pattern.

  17. Concepts and cost trade-offs for land vehicle antennas in satellite mobile communications

    NASA Technical Reports Server (NTRS)

    Haddad, H. A.

    1948-01-01

    Several antenna design concepts, operating at UHF (821 to 825 MHz transmit and 866 to 870 MHz receive bands), with gain ranging between 6 and 12 dBic, that are suitable for land mobile vehicles are presented. The antennas may be used within CONUS and ALASKA to communicate to and from a geosynchronous satellite. Depending on the type of steering mechanism, the antennas are broken down into three categories; (1) electronically scanned arrays with phase shifters, (2) electronically switched arrays with switchable power dividers/combiners, and (3) mechanically steered arrays. The operating characteristics of two of these design concepts, one a conformal antenna with electronic beam steering and the other a nonconformal design with mechanical steering, were evaluated with regard to two and three satellite system. Cost estimates of various antenna concepts were made and plotted against their overall gain performance.

  18. Enhanced spectral efficiency using bandwidth switchable SAW filtering for mobile satellite communications systems

    NASA Technical Reports Server (NTRS)

    Peach, Robert; Malarky, Alastair

    1990-01-01

    Currently proposed mobile satellite communications systems require a high degree of flexibility in assignment of spectral capacity to different geographic locations. Conventionally this results in poor spectral efficiency which may be overcome by the use of bandwidth switchable filtering. Surface acoustic wave (SAW) technology makes it possible to provide banks of filters whose responses may be contiguously combined to form variable bandwidth filters with constant amplitude and phase responses across the entire band. The high selectivity possible with SAW filters, combined with the variable bandwidth capability, makes it possible to achieve spectral efficiencies over the allocated bandwidths of greater than 90 percent, while retaining full system flexibility. Bandwidth switchable SAW filtering (BSSF) achieves these gains with a negligible increase in hardware complexity.

  19. The design and networking of dynamic satellite constellations for global mobile communication systems

    NASA Technical Reports Server (NTRS)

    Cullen, Cionaith J.; Benedicto, Xavier; Tafazolli, Rahim; Evans, Barry

    1993-01-01

    Various design factors for mobile satellite systems, whose aim is to provide worldwide voice and data communications to users with hand-held terminals, are examined. Two network segments are identified - the ground segment (GS) and the space segment (SS) - and are seen to be highly dependent on each other. The overall architecture must therefore be adapted to both of these segments, rather than each being optimized according to its own criteria. Terrestrial networks are grouped and called the terrestrial segment (TS). In the SS, of fundamental importance is the constellation altitude. The effect of the altitude on decisions such as constellation design choice and on network aspects like call handover statistics are fundamental. Orbit resonance is introduced and referred to throughout. It is specifically examined for its useful properties relating to GS/SS connectivities.

  20. Consensus vs Broadcast in Communication Networks with Arbitrary Mobile Omission Faults

    E-print Network

    Godard, Emmanuel

    2011-01-01

    We compare the solvability of the Consensus and Broadcast problems in synchronous communication networks in which the delivery of messages is not reliable. The failure model is the mobile omission faults model. During each round, some messages can be lost and the set of possible simultaneous losses is the same for each round. We investigate these problems for the first time for arbitrary sets of possible failures. Previously, these sets were defined by bounding the numbers of failures. In this setting, we present a new necessary condition for the solvability of Consensus that unifies previous impossibility results in this area. This condition is expressed using Broadcastability properties. As a very important application, we show that when the sets of omissions that can occur are defined by bounding the numbers of failures, counted in any way (locally, globally, etc.), then the Consensus problem is actually equivalent to the Broadcast problem.

  1. Communication: Slow relaxation, spatial mobility gradients, and vitrification in confined films

    SciTech Connect

    Mirigian, Stephen [Department of Materials Science, University of Illinois, Urbana, Illinois 61801 (United States); Frederick Seitz Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States); Schweizer, Kenneth S., E-mail: kschweiz@illinois.edu [Department of Materials Science, University of Illinois, Urbana, Illinois 61801 (United States); Frederick Seitz Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States); Department of Chemistry, University of Illinois, Urbana, Illinois 61801 (United States); Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801 (United States)

    2014-10-28

    Two decades of experimental research indicate that spatial confinement of glass-forming molecular and polymeric liquids results in major changes of their slow dynamics beginning at large confinement distances. A fundamental understanding remains elusive given the generic complexity of activated relaxation in supercooled liquids and the major complications of geometric confinement, interfacial effects, and spatial inhomogeneity. We construct a predictive, quantitative, force-level theory of relaxation in free-standing films for the central question of the nature of the spatial mobility gradient. The key new idea is that vapor interfaces speed up barrier hopping in two distinct, but coupled, ways by reducing near surface local caging constraints and spatially long range collective elastic distortion. Effective vitrification temperatures, dynamic length scales, and mobile layer thicknesses naturally follow. Our results provide a unified basis for central observations of dynamic and pseudo-thermodynamic measurements.

  2. Research activity lllEURECOM -2229 route des Crtes, BP 193 -F-06904 SOPHIA ANTIPOLIS cedex

    E-print Network

    Gesbert, David

    its research activities on three main areas: networking and security, multimedia content and mobile communications. Ulrich Finger, Director Networking and Security Multimedia Communications Mobile Communications and intelligent applications that better serve the needs of single users and communities. MObILE COMMUNICATIONS

  3. Security, Privacy, Trust, and Resource Management in Mobile and Wireless Communications

    Microsoft Academic Search

    Hassan Takabi; James B. D. Joshi

    2013-01-01

    Mobile cloud computing has grown out of two hot technology trends, mobility and cloud. The emergence of cloud computing and its extension into the mobile domain creates the potential for a global, interconnected mobile cloud computing environment that will allow the entire mobile ecosystem to enrich their services across multiple networks. We can utilize significant optimization and increased operating power

  4. Research on the key technologies of mobile digital maps

    NASA Astrophysics Data System (ADS)

    Ji, Cuiling; Xiao, Yongkang; Chi, Tianhe

    2006-10-01

    Mobile and wireless technologies have evolved rapidly in recent years, especially the development of hardware devices, such as PDA and Smart phone. Different kinds of services and applications in these mobile devices, especially Mobile Geographic Information System and Location Based Service have been launched in recent years to help people to establish spatial relationship with the surroundings. Digital Map, which is a useful tool to assist a person for positioning and navigation, is usually included in these services. However, mobility of wireless devices, limited bandwidth of wireless networks, and limited storage capacity of mobile terminals seriously affect the performance of mobile digital maps and its application. In order to boom its application in mobile devices, this paper focuses on four important problems, i.e., data model optimization of mobile digital map, data organization and management at server side and client side respectively, data compression method, representation approaches on mobile terminals. In this paper, we adopt and modify the Europe transportation network standard GDF, accomplish effectively data compression with SVG, and present a new two-layer database structure to organize data. The digital maps can be expressed by multi-approaches, namely layers, districts and scales.

  5. Satellite applications to electric-utility communications needs. [land mobile satellite service

    NASA Technical Reports Server (NTRS)

    Horstein, M.; Barnett, R.

    1981-01-01

    Significant changes in the Nation's electric power systems are expected to result from the integration of new technology, possible during the next decade. Digital communications for monitor and control, exclusive of protective relaying, are expected to double or triple current traffic. A nationwide estimate of 13 Mb/s traffic is projected. Of this total, 8 Mb/s is attributed to the bulk-power system as it is now being operated (4 Mb/s). This traffic could be accommodated by current communications satellites using 3- to 4.5-m-diameter ground terminals costing $35,000 to $70,000 each. The remaining 5-Mb/s traffic is attributed to new technology concepts integrated into the distribution system. Such traffic is not compatible with current satellite technology because it requires small, low-cost ground terminals. Therefore, a high effective isotropic radiated power satellite, such as the one being planned by NASA for the Land Mobile Satellite Service, is required.

  6. Adaptive data rate SSMA system for personal and mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Ikegami, Tetsushi; Takahashi, Takashi; Arakaki, Yoshiya; Wakana, Hiromitsu

    1995-01-01

    An adaptive data rate SSMA (spread spectrum multiple access) system is proposed for mobile and personal multimedia satellite communications without the aid of system control earth stations. This system has a constant occupied bandwidth and has variable data rates and processing gains to mitigate communication link impairments such as fading, rain attenuation and interference as well as to handle variable data rate on demand. Proof of concept hardware for 6MHz bandwidth transponder is developed, that uses offset-QPSK (quadrature phase shift keying) and MSK (minimum shift keying) for direct sequence spread spectrum modulation and handle data rates of 4k to 64kbps. The RS422 data interface, low rate voice and H.261 video codecs are installed. The receiver is designed with coherent matched filter technique to achieve fast code acquisition, AFC (automatic frequency control) and coherent detection with minimum hardware losses in a single matched filter circuit. This receiver structure facilitates variable data rate on demand during a call. This paper shows the outline of the proposed system and the performance of the prototype equipment.

  7. 77 FR 28797 - Redundancy of Communications Systems: Backup Power Private Land Mobile Radio Services: Selection...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-16

    ...FEDERAL COMMUNICATIONS COMMISSION 47 CFR Parts 12 and 90 [DA 11-1838] Redundancy of Communications Systems: Backup Power Private...EA Licensing AGENCY: Federal Communications Commission. ACTION:...

  8. Research in space commercialization, technology transfer, and communications

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Research and internship programs in technology transfer, space commercialization, and information and communications policy are described. The intern's activities are reviewed. On-campus research involved work on the costs of conventional telephone technology in rural areas, an investigation of the lag between the start of a research and development project and the development of new technology, using NASA patent and patent waiver data, studies of the financial impact and economic prospects of a space operation center, a study of the accuracy of expert forecasts of uncertain quantities and a report on frequency coordination in the fixed and fixed satellite services at 4 and 6 GHz.

  9. PANGAEA® - Research Data enters Scholarly Communication

    NASA Astrophysics Data System (ADS)

    Schindler, U.; Diepenbroek, M.; Grobe, H.

    2012-04-01

    PANGAEA® (Data Publisher for Earth & Environmental Science) is an information system which represents the ideal functioning of the ICSU World Data System. Storing about half a million data sets from all fields of geosciences it belongs to the largest archives for observational data. Standard conform interfaces (ISO, OGC, W3C, OAI) enable access from a variety of data and information portals, among them the search engine of PANGAEA® itself (www.pangaea.de) and e.g. large portals like Thomson Reuter's Web of Knowledge and Google. All data sets in PANGAEA® are citable, fully documented, and can be referenced via persistent identifier (Digital Object Identifier - DOI) - a premise for data publication. Together with other ICSU World Data Centers and the Technical Information Library in Germany(TIB) PANGAEA® had a share in the implementation of a DOI based registry for scientific data, which by now is supported by a worldwide consortium of libraries (www.datacite.org). The long term goal is a "crossref for scientific data". Seeing the overall positive impact on the quality and availability of scientific data the PANGAEA® group is offering publication services since several years. They were the main initiators of the "Earth System Science Journal" at Copernicus (http://earth-system-science-data.net/), which is used for standalone peer reviewed data publications. A further milestone was building up strong co-operations with commercial publishers as Elsevier, Nature, Springer, Wiley, AGU, and others. A common web service allows to reference related data in PANGAEA® directly from an articles' abstract page (e.g. ScienceDirect). The next step with commercial publishers is to further integrate the editorial process for the publication of related data with the publication procedures on the journal side, which practically means an extension of the peer review and a synchronization of editorial processes. In this presentation we will introduce the auditorium with the data publication workflow used by PANGAEA®, the technical background of the dynamic linking approach done between conventional publishers and the data repository, and the further steps for integrating editorial processes on both sides. PANGAEA® is operated as a joint long term facility by MARUM at the University Bremen and the Alfred Wegener Institute for Polar and Marine Research (AWI). More than 80% of the funding results from project data management and the implementation of spatial data infrastructures (47 International, 46 European and 37 national projects since the last 12 years - www.pangaea.de/projects).

  10. The 18th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'07) 1-4244-1144-0/07/$25.00 2007 IEEE.

    E-print Network

    Vouyioukas, Demosthenes

    or simply SITs. The DVB-RCS Hub is vital for the operation of the DVB-RCS satellite communications network the new developments in satellite networks such as DVB-RCS. In fact, satellite communication systemsThe 18th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications

  11. The 17th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'06) 1-4244-0330-8/06/$20.00 c2006 IEEE

    E-print Network

    Boyer, Edmond

    The 17th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, coding, etc. for these communication systems is based on a reliable model of the radio propagation the performance of various radio communication systems in a time-variant propagation channel in the same test

  12. Proceedings of 5th Intl. Workshop on Mobile Multimedia Communications MoMuc'98 October 1214, 1998, Berlin Enhancing Wireless Internet Links

    E-print Network

    Polyzos, George C.

    Proceedings of 5th Intl. Workshop on Mobile Multimedia Communications MoMuc'98 October 12­14, 1998­style communications as an overlay, or IP ser­ vice directly. On the other hand, Wireless Local Area Net­ works (WLANs­ The authors are with the Center for Wireless Communications and the Computer Systems Laboratory, Department

  13. Throughput Optimization in Mobile Backbone Networks

    E-print Network

    Craparo, Emily M.

    This paper describes new algorithms for throughput optimization in a mobile backbone network. This hierarchical communication framework combines mobile backbone nodes, which have superior mobility and communication capability, ...

  14. A comparison of metropolitan and non-metropolitan employment characteristics: Indications of the size of non-metropolitan mobile communication services user classes

    NASA Technical Reports Server (NTRS)

    Wilcox, R. E.

    1985-01-01

    The similarities and differences between areas inside and outside U.S. metropolitan areas were evaluated in terms of their commercial/industrial and government employment characteristics. The comparison focuses on the levels, shares, and composition of employment in the commercial/industrial and government sectors that represent potential classes of land mobile communications users. The major findings of the analysis are as follows: (1) non-metropolitan commercial/industrial user classes of land mobile communication services exist in significant numbers; (2) the compositions of non-metropolitan and metropolitan commercial/industrial user classes of land mobile communication services closely resemble each other; (3) non-metropolitan areas have significant levels of the government user classes that represent potential markets for land mobile communication services; and (4) non-metropolitan local governments have a significantly larger proportion of their employment in the primary user classes of private land mobile radio service than do metropolitan local governments.

  15. AMALi - the Airborne Mobile Aerosol Lidar for Arctic research

    NASA Astrophysics Data System (ADS)

    Stachlewska, I. S.; Neuber, R.; Lampert, A.; Ritter, C.; Wehrle, G.

    2010-03-01

    The Airborne Mobile Aerosol Lidar (AMALi) is an instrument developed at the Alfred Wegener Institute for Polar and Marine Research for reliable operation under the challenging weather conditions at the Earth's polar regions. Since 2003 the AMALi has been successfully deployed for measurements in ground-based installation and zenith- or nadir-pointing airborne configurations during several scientific campaigns in the Arctic. The lidar provides backscatter profiles at two wavelengths (355/532 nm or 1064/532 nm) together with the linear depolarization at 532 nm, from which aerosol and cloud properties can be derived. This paper presents the characteristics and capabilities of the AMALi system and gives examples of its usage for airborne and ground-based operations in the Arctic. As this backscatter lidar normally does not operate in aerosol-free layers special evaluation schemes are discussed, the nadir-pointing iterative inversion for the case of an unknown boundary condition and the two-stream approach for the extinction profile calculation if a second lidar system probes the same air mass. Also an intercomparison of the AMALi system with an established ground-based Koldewey Aerosol Raman Lidar (KARL) is given.

  16. Indiana Center for Intercultural Communication: Translating Health Discourse Research into Action

    E-print Network

    Zhou, Yaoqi

    Indiana Center for Intercultural Communication: Translating Health Discourse Research into Action Ulla Connor, PhD, Director School of Liberal Arts Indiana University ­ Purdue University Indianapolis Abstract The Indiana Center for Intercultural Communication (ICIC) is a university-based research

  17. Application of WSN in Mine Emergency Communication System

    Microsoft Academic Search

    Junxuan Wang; Yanyan Zhang; Guangyue Lu

    2008-01-01

    A scheme based on wireless sensor networks (WSN) which combined with mobile communications technology using in mines emergence communications was researched. Any safety parameters of coal mines - such as gas concentration and co concentration - were obtained by WSN systems in emergency or coal disaster, and then data were collected and transmitted to data processing center with mobile communication

  18. EmotionSense: a mobile phones based adaptive platform for experimental social psychology research

    Microsoft Academic Search

    Kiran K. Rachuri; Mirco Musolesi; Cecilia Mascolo; Peter J. Rentfrow; Chris Longworth; Andrius Aucinas

    2010-01-01

    Today's mobile phones represent a rich and powerful computing platform, given their sensing, processing and communication capabilities. Phones are also part of the everyday life of billions of people, and therefore represent an exceptionally suitable tool for conducting social and psychological experiments in an unobtrusive way. de the ability of sensing individual emotions as well as activities, verbal and proximity

  19. Optimizing Communications Between Arctic Residents and IPY Scientific Researchers

    NASA Astrophysics Data System (ADS)

    Stapleton, M.; Carpenter, L.

    2007-12-01

    BACKGROUND International Polar Year, which was launched in March 2007, is an international program of coordinated, interdisciplinary scientific research on Earth's polar regions. The northern regions of the eight Arctic States (Canada, Alaska (USA), Russia, Sweden, Norway, Finland. Iceland and Greenland (Denmark) have significant indigenous populations. The circumpolar Arctic is one of the least technologically connected regions in the world, although Canada and others have been pioneers in developing and suing Information and Communication Technology (ICT) in remote areas. The people living in this vast geographic area have been moving toward taking their rightful place in the global information society, but are dependent on the outreach and cooperation of larger mainstream societies. The dominant medium of communication is radio, which is flexible in accommodating multiple cultures, languages, and factors of time and distance. The addition of newer technologies such as streaming on the Internet can increase access and content for all communities of interest, north and south. The Arctic Circle of Indigenous Communicators (ACIC) is an independent association of professional Northern indigenous media workers in the print, radio, television, film and Internet industries. ACIC advocates the development of all forms of communication in circumpolar North areas. It is international in scope. Members are literate in English, French, Russian and many indigenous languages. ACIC has proposed the establishment of a headquarters for monitoring IPY projects are in each area, and the use of community radio broadcasters to collect and disseminate information about IPY. The cooperation of Team IPY at the University of Colorado, Arctic Net at Laval University, and others, is being developed. ACIC is committed to making scientific knowledge gained in IPY accessible to those most affected - residents of the Arctic. ABSTRACT The meeting of the American Geophysical Union will be held in San Francisco on December 10 to 14, 2007. One component of this conference is entitled « Education, Outreach and Communications During IPY and Beyond ». ACIC proposes to present a discussion paper, « Optimizing Communications Between Arctic Residents and IPY Scientific Researchers », describing the status of IPY outreach and communications in the Arctic at this time. The paper will be complemented by photographs which illustrate the context of communication activity in these regions. ACIC has an existing international network of indigenous northern communicators. The IPY Northern Coordination Offices in Canada, and key informants in Alaska, RAIPON in the Russian Federation, and the Association of Sami Journalists, will be interviewed to determine involvement in IPY activities planned and/or undertaken. The level of community and professional awareness will be surveyed through interviews with community radio personnel. Aspirations and expectations for further cooperation with IPY reseearchers will be determined. Barriers and shortfalls will be identified. The usability and potential of current communications will be assessed. Endorsed IPY projects will be contacted to determine their Arctic communication plans and activities, barriers and opportunities. Information gained from the Joint Committee Assessment in October will be considered in the context of northern informant input. Conclusions and recommendations will reported, with the goal of optimizing opportunities to connect indigenous Arctic residents and IPY scientific research centres.

  20. Fabric antennas for mobile telephony integrated within clothing Philips Research Laboratories, Redhill, UK

    E-print Network

    Haddadi, Hamed

    Fabric antennas for mobile telephony integrated within clothing P.J.Massey Philips Research Laboratories, Redhill, UK Abstract: All sorts of consumer electronics are being integrated into clothing. This paper describes work integrating mobile phone antennas. Conducting fabrics offer antenna performance

  1. Orientation and Mobility for Blind Infants. Abstract XIII: Research & Resources on Special Education.

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Handicapped and Gifted Children, Reston, VA.

    A federally funded research report, titled "The Development of a Program in Orientation and Mobility for Multi-Handicapped Blind Infants" by Randall Harley et al., is briefly summarized in this one-page abstract. The report discusses the development of the "Peabody Mobility Kit for Infants," a package of assessment and training materials for use…

  2. Perception and mobility research at Defence R&D Canada for UGVs in complex terrain

    NASA Astrophysics Data System (ADS)

    Trentini, Michael; Collier, Jack; Beckman, Blake; Digney, Bruce; Vincent, Isabelle

    2007-04-01

    The Autonomous Intelligent Systems Section at Defence R&D Canada - Suffield envisions autonomous systems contributing to decisive operations in the urban battle space. In this vision, teams of unmanned ground, air, and marine vehicles, and unattended ground sensors will gather and coordinate information, formulate plans, and complete tasks. The mobility requirement for ground-based mobile systems operating in urban settings must increase significantly if robotic technology is to augment human efforts in military relevant roles and environments. In order to achieve its objective, the Autonomous Intelligent Systems Section is pursuing research that explores the use of intelligent mobility algorithms designed to improve robot mobility. Intelligent mobility uses sensing and perception, control, and learning algorithms to extract measured variables from the world, control vehicle dynamics, and learn by experience. These algorithms seek to exploit available world representations of the environment and the inherent dexterity of the robot to allow the vehicle to interact with its surroundings and produce locomotion in complex terrain. However, a disconnect exists between the current state-of-the-art in perception systems and the information required for novel platforms to interact with their environment to improve mobility in complex terrain. The primary focus of the paper is to present the research tools, topics, and plans to address this gap in perception and control research. This research will create effective intelligence to improve the mobility of ground-based mobile systems operating in urban settings to assist the Canadian Forces in their future urban operations.

  3. Teacher Effectiveness, Mobility, and Attrition in Florida: A Descriptive Analysis. Research Brief

    ERIC Educational Resources Information Center

    National Center on Performance Incentives, 2008

    2008-01-01

    While there has been substantial research studying the factors that influence teachers' career decisions, there is far less literature on the relationship between teacher effectiveness, mobility, and attrition. In the paper "Teacher Effectiveness, Mobility, and Attrition in Florida: A Descriptive Analysis," Martin West and Matthew Chingos address…

  4. Research paper Behavior of fluid-mobile elements in serpentines from abyssal to subduction

    E-print Network

    Research paper Behavior of fluid-mobile elements in serpentines from abyssal to subduction. In order to constrain geochemical behavior of fluid-mobile elements hosted by serpentine phases during indicating extensive fluid­rock interaction. In situ analyses allow distinction of three types of serpentines

  5. Differential signaling spread-spectrum modulation of the LED visible light wireless communications using a mobile-phone camera

    NASA Astrophysics Data System (ADS)

    Chen, Shih-Hao; Chow, Chi-Wai

    2015-02-01

    Visible light communication (VLC) using spread spectrum modulation (SSM) and differential signaling (DS), detected by a mobile-phone camera is proposed and demonstrated for the first time to provide high immunity to background ambient light interference. The SSM signal provides the coding gain while the DS scheme enhances the clock recovery particular under high background ambient light. Experiment results confirm the feasibility of the proposed scheme, showing that the proposed system has 6-dB gain comparing with the traditional on-off keying (OOK) modulation under background ambient light of 3000 lux. The direct incident ambient light to the mobile-phone camera is 520 lux.

  6. How the mobile communication markets differ in China, the U.S., and Europe

    Microsoft Academic Search

    Xiaoni Zhang; Victor R. Prybutok

    2005-01-01

    Despite the 2001 downturn in the global telecommunications market, the mobile penetration rate in China is increasing due to the elimination or reduction of mobile connection fees. The mobile market worldwide is dynamic in terms of technology development, and competition is aggressive. The potential size and growth rate of the Chinese, U.S., and European mobile markets warrant examination of the

  7. OSI-compatible protocols for mobile-satellite communications: The AMSS experience

    NASA Technical Reports Server (NTRS)

    Moher, Michael

    1990-01-01

    The protocol structure of the international aeronautical mobile satellite service (AMSS) is reviewed with emphasis on those aspects of protocol performance, validation, and conformance which are peculiar to mobile services. This is in part an analysis of what can be learned from the AMSS experience with protocols which is relevant to the design of other mobile satellite data networks, e.g., land mobile.

  8. Low-mobility channel tracking for MIMO-OFDM communication systems

    NASA Astrophysics Data System (ADS)

    Pagadarai, Srikanth; Wyglinski, Alexander M.; Anderson, Christopher R.

    2013-12-01

    It is now well understood that by exploiting the available additional spatial dimensions, multiple-input multiple-output (MIMO) communication systems provide capacity gains, compared to a single-input single-output systems without increasing the overall transmit power or requiring additional bandwidth. However, these large capacity gains are feasible only when the perfect knowledge of the channel is available to the receiver. Consequently, when the channel knowledge is imperfect, as is common in practical settings, the impact of the achievable capacity needs to be evaluated. In this study, we begin with a general MIMO framework at the outset and specialize it to the case of orthogonal frequency division multiplexing (OFDM) systems by decoupling channel estimation from data detection. Cyclic-prefixed OFDM systems have attracted widespread interest due to several appealing characteristics not least of which is the fact that a single-tap frequency-domain equalizer per subcarrier is sufficient due to the circulant structure of the resulting channel matrix. We consider a low-mobility wireless channel which exhibits inter-block channel variations and apply Kalman tracking when MIMO-OFDM communication is performed. Furthermore, we consider the signal transmission to contain a stream of training and information symbols followed by information symbols alone. By relying on predicted channel states when training symbols are absent, we aim to understand how the improvements in channel capacity are affected by imperfect channel knowledge. We show that the Kalman recursion procedure can be simplified by the optimal minimum mean square error training design. Using the simplified recursion, we derive capacity upper and lower bounds to evaluate the performance of the system.

  9. Design and Implementation of Mobile English Learning

    Microsoft Academic Search

    Shuyun Han; Weiliang Kong; Qingtang Liu; Lian Zhou

    2010-01-01

    With the rapid development of computer and the mobile communication technology, mobile learning arises at the historic moment, which makes people gain learning environment and resources anytime and anywhere. As English has the characters of weak systematic and trivial knowledge, we make a research of the development of resources to provide learners Flake Learning. Firstly, we make a research of

  10. Manned earth orbital laboratories to perform communications/navigation research.

    NASA Technical Reports Server (NTRS)

    Waltz, D. M.; Quantock, C. W.

    1972-01-01

    Review of the feasibility of manned earth orbiting laboratories in the 1980s for solving problems identified with operational communication and navigation systems. A program of experiments recommended for implementation in the 1980 to 1990 period is presented. Equipment for conducting experiments is listed. Conceptual designs of laboratories which could be carried to orbit by the forthcoming NASA Space Shuttle Orbiter and then operated on orbit by an experimenter crew are discussed. Studies of the expected benefits, together with investigations of the configurations, mission considerations, and equipment selection result in the conclusion that manned communication/navigation research laboratories in earth orbit would be practical and effective, and that the experiments performed could derive meaningful information having application to future unmanned operational systems.

  11. The 18th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'07) SUPPORTING FIRST PERSON SHOOTER GAMES IN WIRELESS LOCAL AREA

    E-print Network

    The 18th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications an affect on WLANs. As with most Internet application traffic, FPS games exhibit uplink/downlink asymmetry

  12. A comparison study of the uplink performance of W-CDMA and OFDM for mobile multimedia communications via LEO satellites

    Microsoft Academic Search

    A. Papathanassiou; A. K. Salkintzis; P. T. Mathiopoulos

    2001-01-01

    This article presents a comparison study of the uplink performance of two well-known transmission schemes, W-CDMA and OFDM, for mobile multimedia communications via LEO satellite. In order to provide a framework for a fair comparison we have considered for both schemes common parameters, including identical channel bandwidth, coding\\/decoding algorithms and similar net data rate. The values of these parameters have

  13. Cryptanalysis of the end-to-end security protocol for mobile communications with end-user identification\\/authentication

    Microsoft Academic Search

    YongBin Zhou; ZhenFeng Zhang; DengGuo Feng

    2005-01-01

    This letter shows that the end-to-end security protocol for mobile communications with end-user identification\\/authentication due to Chang et al., (2004) has a serious security flaw. We demonstrate this by presenting a simple but powerful impersonation attack against the protocol so that the protocol is insecure against impersonation attack. Hence, the protocol cannot achieve the claimed security. To overcome such a

  14. The application of a novel two-way mobile satellite communications and vehicle tracking system to the transportation industry

    Microsoft Academic Search

    I. M. Jacobs; A. Salmasi; T. J. Bernard

    1991-01-01

    A two-way mobile satellite communications and vehicle position reporting system currently operational in the US and Europe is described. The system characteristics and service operations are described in detail, and technical descriptions of the equipment and signal processing techniques are provided. The application of this technology to the land transportation industry, specifically the over-the-road truckload motor carrier segment, and the

  15. 7 CFR 3022.8 - Communication of research misconduct policies and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 false Communication of research misconduct policies and procedures...FINANCIAL OFFICER, DEPARTMENT OF AGRICULTURE RESEARCH INSTITUTIONS CONDUCTING USDA-FUNDED EXTRAMURAL RESEARCH; RESEARCH MISCONDUCT § 3022.8...

  16. Performance of the unique-word-reverse-modulation type demodulator for mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Dohi, Tomohiro; Nitta, Kazumasa; Ueda, Takashi

    1993-01-01

    This paper proposes a new type of coherent demodulator, the unique-word (UW)-reverse-modulation type demodulator, for burst signal controlled by voice operated transmitter (VOX) in mobile satellite communication channels. The demodulator has three individual circuits: a pre-detection signal combiner, a pre-detection UW detector, and a UW-reverse-modulation type demodulator. The pre-detection signal combiner combines signal sequences received by two antennas and improves bit energy-to-noise power density ratio (E(sub b)/N(sub 0)) 2.5 dB to yield 10(exp -3) average bit error rate (BER) when carrier power-to-multipath power ratio (CMR) is 15 dB. The pre-detection UW detector improves UW detection probability when the frequency offset is large. The UW-reverse-modulation type demodulator realizes a maximum pull-in frequency of 3.9 kHz, the pull-in time is 2.4 seconds and frequency error is less than 20 Hz. The performances of this demodulator are confirmed through computer simulations and its effect is clarified in real-time experiments at a bit rate of 16.8 kbps using a digital signal processor (DSP).

  17. 75 FR 8112 - In the Matter of Certain Mobile Telephones and Wireless Communication Devices Featuring Digital...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-23

    ...Communication Devices Featuring Digital Cameras, and Components Thereof...International Trade Commission. ACTION: Institution of investigation...communication devices featuring digital cameras, and components thereof by...communication devices featuring digital cameras, or [[Page 8113

  18. One exhibition, many goals. Combining scientific research and risk communication

    NASA Astrophysics Data System (ADS)

    Charrière, Marie; Bogaard, Thom; Junier, Sandra; Malet, Jean-Philippe; Mostert, Erik

    2015-04-01

    How effective is visual communication to increase awareness of natural hazards and risks? To answer this research question, we developed a research design that was at the same time an experimental setting and an actual communication effort. Throughout the full length of the 2-years project held in the Ubaye valley (southeastern France), we collaborated with local and regional stakeholders (politicians and technicians). During a consultation phase, the communication context was determined, the audience of the project was defined and finally the testing activity-communication effort was determined. We were offered the opportunity to design an exhibition for the local public library. In a consultation phase that corresponded to the design of the exhibition, the stakeholders contributed to its content as well as helping with the funding of the exhibition. Finally, during the experimentation phase, the stakeholders participated in advertising the activity, gathering of participants and designing the scientific survey. In order to assess the effects of the exhibition on risk awareness, several groups of children, teenagers and adults were submitted to a research design, consisting of 1) a pre-test, 2) the visit of the exhibition and 3) a post-test similar to the pre-test. In addition, the children answered a second post-test 3 months after the visit. Close ended questions addressed the awareness indicators mentioned in the literature, i.e. worry level, previous experiences with natural hazards events, exposure to awareness raising, ability to mitigate/respond/prepare, attitude to risk, and demographics. In addition, the post-test included several satisfaction questions concerning the visual tools displayed in the exhibition. A statistical analysis of the changes between the pre- and post- tests (paired t-test, Wilcoxon signed-rank test and bootstrapping) allowed to verify whether the exhibition had an impact on risk awareness or not. In order to deduce which variable influenced the observed changes, an ordinal regression was performed. In addition, to deduce the attractiveness of each visual tool independently, the visitors' paths were tracked using RFID (Radio Frequency Identification) technique, from which their time spent around certain visuals could be assessed. While the process of creating an exhibition as a real communication effort and a testing activity will be discussed, the results of the experiment will be presented. In particular, we will show for which natural hazard the most awareness changes were measured and with which factors they are assessed. Moreover, the attractiveness of each visual tools will be presented.

  19. Mobile Informal Learning

    Microsoft Academic Search

    Christian Glahn; Dirk Börner

    2010-01-01

    Mobile technologies play an important role in contemporary communication. Starting from mobile telephony, mobile devices are increasingly becoming ubiquitous devices for personal information management and communication through different channels. These new devices shape our perception of information, communication, participation, and learning. Moreover, new and smart mobile technology challenges the current views on education and learning more radically then the worldwide

  20. The new frontier of communications research: smart grid and smart metering

    Microsoft Academic Search

    Zhong Fan; Georgios Kalogridis; Costas Efthymiou; Mahesh Sooriyabandara; Mutsumu Serizawa; Joe McGeehan

    2010-01-01

    This paper discusses some of the challenges and opportunities of communications research in the area of smart grids and smart metering. It is clear that the communications research community has been actively seeking the 'next big thing' after interests in recent hot topics such as cognitive radio, cooperative communications, and MIMO have more or less peaked. We argue that the