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1

Secure End-to-End Communication over GSM and PSTN Networks  

Microsoft Academic Search

GSM (Global System for Mobiles) is the most widely spread mobile communication system in the world. An important objective in mobile communication systems is secure speech communication. GSM suffers from various security weaknesses. The GSM voice traffic is secure outside the core network but it has no security over the core network. This system can be made thoroughly secure by

Saad Islam; Fatima Ajmal; Salman Ali; Jawad Zahid; Adnan Rashdi

2009-01-01

2

Mobility Detection Using Everyday GSM Traces  

Microsoft Academic Search

Recognition of everyday physical activities is difficult due to the challenges of building informative, yet unobtrusive sensors. The most widely deployed and used mobile computing device today is the mobile phone, which presents an obvious candidate for recognizing activities. This paper explores how coarse-grained GSM data from mobile phones can be used to recognize high-level properties of user mobility, and

Timothy Sohn; Alex Varshavsky; Anthony Lamarca; Mike Y. Chen; Tanzeem Choudhury; Ian E. Smith; Sunny Consolvo; Jeffrey Hightower; William G. Griswold; Eyal De Lara

2006-01-01

3

GSM Mobile Phone Based Communication of Multimedia Information : A Case Study Through a practical application, this paper studies the capacity of the GSM network, a wireless mobile phone network  

E-print Network

of important and valuable goods such as transfer of cash between banks. One simple solution is to keep track such as radio. Although this is in fact a waste of resources, it seems to be the only way of doing so. The data captured is transmitted from the remote object to the central station through the GSM mobile phone

Wong, Kenneth K.Y.

4

Long-term exposure to mobile communication radiation: an analysis of time-variability of electric field level in GSM900 downlink channels.  

PubMed

Interest for knowing long-term human exposure levels due to mobile communications has increased in the last years. It has been shown that short-term exposure assessment made under standard procedural restrictions is not reliable when it comes to conclusions on long-term exposure levels. The present work is the result of a several week analysis of time variability of electric field level inside traffic and control channels of the GSM900 mobile communication downlink band and it indicates that a temporal model to allow future predictions of exposure on the long run is obtainable. Collecting, processing and statistically analysing the data provide expression of the maximum and weighted field strengths and their evolution in time. Specific electromagnetic footprints of the channels have been extracted, differentiations between their characteristics have been emphasised and practical advice is provided, with the scope of contributing to the development of reliable procedures for long-term exposure assessment. PMID:22908352

Miclaus, Simona; Bechet, Paul; Gheorghevici, Marius

2013-04-01

5

A communication architecture to access data services through GSM  

E-print Network

present a communication architecture for accessing TCP/IP networks (mainly Internet) through GSM. We exploit the existing and widely used TCP/IP communication architecture, but also consider the specific features of wireless links and GSM networks. Our proposal is based in the indirect model of client/server

Miguel-Alonso, José

6

Experimental and numerical assessment of low-frequency current distributions from UMTS and GSM mobile phones  

NASA Astrophysics Data System (ADS)

The evaluation of the exposure from mobile communication devices requires consideration of electromagnetic fields (EMFs) over a broad frequency range from dc to GHz. Mobile phones in operation have prominent spectral components in the low-frequency (LF) and radio-frequency (RF) ranges. While the exposure to RF fields from mobile phones has been comprehensively assessed in the past, the LF fields have received much less attention. In this study, LF fields from mobile phones are assessed experimentally and numerically for the global system for mobile (GSM) and universal mobile telecommunications system (UMTS) communication systems and conclusions about the global (LF and RF) EMF exposure from both systems are drawn. From the measurements of the time-domain magnetic fields, it was found that the contribution from the audio signal at a normal speech level, i.e., -16 dBm0, is the same order of magnitude as the fields induced by the current bursts generated from the implementation of the GSM communication system at maximum RF output level. The B-field induced by currents in phones using the UMTS is two orders of magnitude lower than that induced by GSM. Knowing that the RF exposure from the UMTS is also two orders of magnitude lower than from GSM, it is now possible to state that there is an overall reduction of the exposure from this communication system.

Gosselin, Marie-Christine; Kühn, Sven; Kuster, Niels

2013-12-01

7

GSM Technology as a Communication Media for an Autonomous Unmanned Aerial Vehicle GSM Technology as a Communication Media for an  

E-print Network

suites. Data links, such as wireless Ethernet or radio modems that use open frequency bands are often and buildings, etc. GSM and its related technologies GPRS, EDGE, 3GSM offer an interesting communications. A prototype network is presented, that was created between two UAVs and a ground operator using GPRS

Doherty, Patrick

8

Dual-band miniaturized microstrip fractal antenna for a small GSM 1800 + UMTS mobile handset  

Microsoft Academic Search

A novel microstrip GSM1800 + UMTS dual-band antenna based on a Koch fractal shaped patch element is presented. The antenna has been developed to be used in small handsets of future multi-standard mobile communication systems. The fractal miniaturization technique has been combined with a patch inverted F antenna (PIFA) structure. The effect of a small ground plane has been taken

J. Guterman; A. A. Moreira; C. Peixerio

2004-01-01

9

A communication architecture to access data services through GSM  

Microsoft Academic Search

In this paper we present a communication architecture for accessing TCP\\/IP networks (mainly Internet) through GSM. We e xploit t he e xisting and widely used TCP\\/IP communication architecture, but also consider the specific features of wireless links and GSM networks. Our proposal is based in the indirect model of client\\/server interaction, where a n intermediate e lement acts as

J. M. Rivadeneyra Sicilia; J. Miguel-Alonso

1998-01-01

10

An Electronic Voting System Using GSM Mobile Technology  

E-print Network

An Electronic Voting System Using GSM Mobile Technology Yang Feng, Siaw-Lynn Ng and Scarlet://www.rhul.ac.uk/mathematics/techreports #12;Abstract Electronic voting systems have the potential to improve traditional voting procedures by providing added convenience and flexibility to the voter. Nu- merous electronic voting schemes have been

Dent, Alexander W.

11

Analysis of the influence of the power control and discontinuous transmission on RF exposure with GSM mobile phones  

Microsoft Academic Search

Biological studies and, in particular, epidemiological ones require the estimation of the RF exposure induced by a mobile phone. Due to the different techniques used by global system mobile (GSM) and digital communication system (DCS) such as power control and discontinuous transmission, the power emitted by a handset is largely variable. As these parameters depend on the environment and the

Joe Wiart; Christian Dale; Ada Victoria Bosisio; Alain Le Cornec

2000-01-01

12

The use of SS7 and GSM to support high density personal communications  

Microsoft Academic Search

The authors present an organized method for quantifying the Signaling System 7 (SS7) traffic load associated with terminal mobility when the pan-European standard GSM is used for personal communication networks (PCNs). They use CCIR parameters for an extremely dense, outdoor center-city pedestrian environment to illustrate the possible heavy signaling load. Using the example parameters, the additional SS7 network burden is

KATHLEEN S. MEIER-HELLSTERN; EDUARDO ALONSO; DOUGLAS R. O'NEIL

1992-01-01

13

A Data Modem for GSM Voice Channel  

Microsoft Academic Search

This paper introduces a novel approach to data communication over the global system for mobile communications (GSM) voice channel. It is based on the concept of ldquosymbolsrdquo-a set of predefined signals with finite bandwidths. Data are encoded into the symbols, and the symbols are voice coded as they were speech, modulated into the GSM signal, sent over the air, GSM

Christoph K. LaDue; Vitaliy V. Sapozhnykov; Kurt S. Fienberg

2008-01-01

14

Short GSM mobile phone exposure does not alter human auditory brainstem response  

Microsoft Academic Search

BACKGROUND: There are about 1.6 billion GSM cellular phones in use throughout the world today. Numerous papers have reported various biological effects in humans exposed to electromagnetic fields emitted by mobile phones. The aim of the present study was to advance our understanding of potential adverse effects of the GSM mobile phones on the human hearing system. METHODS: Auditory Brainstem

Gábor Stefanics; Lóránd Kellényi; Ferenc Molnár; Györgyi Kubinyi; György Thuróczy; István Hernádi

2007-01-01

15

Electromagnetic interference of GSM mobile phones with the implantable deep brain stimulator, ITREL-III  

PubMed Central

Background The purpose was to investigate mobile phone interference with implantable deep brain stimulators by means of 10 different 900 Mega Hertz (MHz) and 10 different 1800 MHz GSM (Global System for Mobile Communications) mobile phones. Methods All tests were performed in vitro using a phantom especially developed for testing with deep brain stimulators. The phantom was filled with liquid phantom materials simulating brain and muscle tissue. All examinations were carried out inside an anechoic chamber on two implants of the same type of deep brain stimulator: ITREL-III from Medtronic Inc., USA. Results Despite a maximum transmitted peak power of mobile phones of 1 Watt (W) at 1800 MHz and 2 W at 900 MHz respectively, no influence on the ITREL-III was found. Neither the shape of the pulse form changed nor did single pulses fail. Tests with increased transmitted power using CW signals and broadband dipoles have shown that inhibition of the ITREL-III occurs at frequency dependent power levels which are below the emissions of GSM mobile phones. The ITREL-III is essentially more sensitive at 1800 MHz than at 900 MHz. Particularly the frequency range around 1500 MHz shows a very low interference threshold. Conclusion These investigations do not indicate a direct risk for ITREL-III patients using the tested GSM phones. Based on the interference levels found with CW signals, which are below the mobile phone emissions, we recommend similar precautions as for patients with cardiac pacemakers: 1. The phone should be used at the ear at the opposite side of the implant and 2. The patient should avoid carrying the phone close to the implant. PMID:12773204

Kainz, Wolfgang; Alesch, Francois; Chan, Dulciana Dias

2003-01-01

16

Nerve cell damage in mammalian brain after exposure to microwaves from GSM mobile phones.  

PubMed Central

The possible risks of radio-frequency electromagnetic fields for the human body is a growing concern for our society. We have previously shown that weak pulsed microwaves give rise to a significant leakage of albumin through the blood-brain barrier. In this study we investigated whether a pathologic leakage across the blood-brain barrier might be combined with damage to the neurons. Three groups each of eight rats were exposed for 2 hr to Global System for Mobile Communications (GSM) mobile phone electromagnetic fields of different strengths. We found highly significant (p< 0.002) evidence for neuronal damage in the cortex, hippocampus, and basal ganglia in the brains of exposed rats. PMID:12782486

Salford, Leif G; Brun, Arne E; Eberhardt, Jacob L; Malmgren, Lars; Persson, Bertil R R

2003-01-01

17

GSM mobile phone radiation suppresses brain glucose metabolism  

Microsoft Academic Search

We investigated the effects of mobile phone radiation on cerebral glucose metabolism using high-resolution positron emission tomography (PET) with the 18F-deoxyglucose (FDG) tracer. A long half-life (109 minutes) of the 18F isotope allowed a long, natural exposure condition outside the PET scanner. Thirteen young right-handed male subjects were exposed to a pulse-modulated 902.4 MHz Global System for Mobile Communications signal

Myoung Soo Kwon; Victor Vorobyev; Sami Kännälä; Matti Laine; Juha O Rinne; Tommi Toivonen; Jarkko Johansson; Mika Teräs; Harri Lindholm; Tommi Alanko; Heikki Hämäläinen

2011-01-01

18

Effects of electromagnetic fields emitted by mobile phones (GSM 900 and WCDMA/UMTS) on the macrostructure of sleep.  

PubMed

In the present double-blind, randomized, sham-controlled cross-over study, possible effects of electromagnetic fields emitted by Global System for Mobile Communications (GSM) 900 and Wideband Code-Division Multiple Access (WCDMA)/Universal Mobile Telecommunications System (UMTS) cell-phones on the macrostructure of sleep were investigated in a laboratory environment. An adaptation night, which served as screening night for sleep disorders and as an adjustment night to the laboratory environment, was followed by 9 study nights (separated by a 2-week interval) in which subjects were exposed to three exposure conditions (sham, GSM 900 and WCDMA/UMTS). The sample comprised 30 healthy male subjects within the age range 18-30 years (mean ± standard deviation: 25.3 ± 2.6 years). A cell-phone usage at maximum radio frequency (RF) output power was simulated and the transmitted power was adjusted in order to approach, but not to exceed, the specific absorption rate (SAR) limits of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines for general public exposure (SAR(10g) = 2.0 W kg(-1)). In this study, possible effects of long-term (8 h) continuous RF exposure on the central nervous system were analysed during sleep, because sleep is a state in which many confounding intrinsic and extrinsic factors (e.g. motivation, personality, attitude) are eliminated or controlled. Thirteen of 177 variables characterizing the initiation and maintenance of sleep in the GSM 900 and three in the WCDMA exposure condition differed from the sham condition. The few significant results are not indicative of a negative impact on sleep architecture. From the present results there is no evidence for a sleep-disturbing effect of GSM 900 and WCDMA exposure. PMID:20561179

Danker-Hopfe, Heidi; Dorn, Hans; Bahr, Achim; Anderer, Peter; Sauter, Cornelia

2011-03-01

19

GSM mobile phone radiation suppresses brain glucose metabolism  

PubMed Central

We investigated the effects of mobile phone radiation on cerebral glucose metabolism using high-resolution positron emission tomography (PET) with the 18F-deoxyglucose (FDG) tracer. A long half-life (109?minutes) of the 18F isotope allowed a long, natural exposure condition outside the PET scanner. Thirteen young right-handed male subjects were exposed to a pulse-modulated 902.4?MHz Global System for Mobile Communications signal for 33?minutes, while performing a simple visual vigilance task. Temperature was also measured in the head region (forehead, eyes, cheeks, ear canals) during exposure. 18F-deoxyglucose PET images acquired after the exposure showed that relative cerebral metabolic rate of glucose was significantly reduced in the temporoparietal junction and anterior temporal lobe of the right hemisphere ipsilateral to the exposure. Temperature rise was also observed on the exposed side of the head, but the magnitude was very small. The exposure did not affect task performance (reaction time, error rate). Our results show that short-term mobile phone exposure can locally suppress brain energy metabolism in humans. PMID:21915135

Kwon, Myoung Soo; Vorobyev, Victor; Kännälä, Sami; Laine, Matti; Rinne, Juha O; Toivonen, Tommi; Johansson, Jarkko; Teräs, Mika; Lindholm, Harri; Alanko, Tommi; Hämäläinen, Heikki

2011-01-01

20

Comparative analysis of distributed architecture with existing GSM mobile architecture  

Microsoft Academic Search

Abstrac:The present and next generation mobile network will support terminal mobility, personal mobility and service provider portability, making global roaming seamless. In future we need to balance heavy load. This necessitates research into the design and performance of high throughput database technologies used in mobile systems to ensure that future systems will be able to carry efficiently the anticipated loads.

G. K. Viju; Khalid Ahmed Ibrahim

2011-01-01

21

Data Transmission over GSM Adaptive Multi Rate Voice Channel Using Speech-Like Symbols  

Microsoft Academic Search

This paper introduces a new method to transmit digital data through Global System for Mobile communications (GSM) voice channel. A novel algorithm is proposed to design a set of Speech-Like (SL) symbols which leads to design a GSM voice channel data modem to modulate and demodulate data on GSM Adaptive Multi Rate (AMR) voice codec which consist of different bit-rates.

Ali Shahbazi; Amir Hossein Rezaei; Abolghasem Sayadiyan; Saeed Mosayyebpour

2010-01-01

22

Carcinogenicity study of GSM and DCS wireless communication signals in B6C3F1 mice.  

PubMed

The purpose of this study using a total of 1170 B6C3F1 mice was to detect and evaluate possible carcinogenic effects in mice exposed to radio-frequency-radiation (RFR) from Global System for Mobile Communication (GSM) and Digital Personal Communications System (DCS) handsets as emitted by handsets operating in the center of the communication band, that is, at 902 MHz (GSM) and 1747 MHz (DCS). Restrained mice were exposed for 2 h per day, 5 days per week over a period of 2 years to three different whole-body averaged specific absorption rate (SAR) levels of 0.4, 1.3, 4.0 mW/g bw (SAR), or were sham exposed. Regarding the organ-related tumor incidence, pairwise Fisher's test did not show any significant increase in the incidence of any particular tumor type in the RF exposed groups as compared to the sham exposed group. Interestingly, while the incidences of hepatocellular carcinomas were similar in EMF and sham exposed groups, in both studies the incidences of liver adenomas in males decreased with increasing dose levels; the incidences in the high dose groups were statistically significantly different from those in the sham exposed groups. Comparison to published tumor rates in untreated mice revealed that the observed tumor rates were within the range of historical control data. In conclusion, the present study produced no evidence that the exposure of male and female B6C3F1 mice to wireless GSM and DCS radio frequency signals at a whole body absorption rate of up to 4.0 W/kg resulted in any adverse health effect or had any cumulative influence on the incidence or severity of neoplastic and non-neoplastic background lesions, and thus the study did not provide any evidence of RF possessing a carcinogenic potential. PMID:17019729

Tillmann, Thomas; Ernst, Heinrich; Ebert, Sven; Kuster, Niels; Behnke, Wolfgang; Rittinghausen, Susanne; Dasenbrock, Clemens

2007-04-01

23

Assessment of RF radiation levels in the vicinity of 60 GSM mobile phone base stations in Iran.  

PubMed

Increasing development of mobile communication infrastructure while enhancing availability of the technology raises concerns among the public, who see more cell towers erected each day, about possible health effects of electromagnetic radiations. Thereon, a survey of radio-frequency radiation from 60 GSM base stations was carried out in Tehran, Iran at several places mostly located in major medical and educational centres. Measurements were performed at 15 locations near each base station site, i.e. 900 locations in total. Since there are other RF radiation sources such as broadcasting services whose carrier frequencies are <3 GHz, the whole band of 27 MHz to 3 GHz has been assessed for hazardous exposures as well. The results were compared with the relevant guideline of International Commission on Non-Ionising Radiation Protection and that of Iran, confirming radiation exposure levels being satisfactorily below defined limits and non-detrimental. PMID:23222504

Nayyeri, Vahid; Hashemi, Seyed Mohammad; Borna, Maryam; Jalilian, Hamid-Reza; Soleimani, Mohammad

2013-07-01

24

Intellectual property rights and standardization: the case of GSM  

Microsoft Academic Search

This paper investigates the role of intellectual property rights (IPRs) in the process of standardization in the telecommunications industry. We take the global system for mobile communications (GSM) case as a highly relevant example, being part of a high-tech industry in which standards play a large role. In the process of designing the GSM standard, a lot of attention has

Rudi Bekkers; Bart Verspagen; Jan Smits

2002-01-01

25

Effects of Mobile Communication  

Microsoft Academic Search

Before reviewing some of the key consequences of mobile communication technology, a brief discussion of how they fit within the media effects paradigm is in order. At the risk of oversimplification, we understand the media effects paradigm as a framework for understanding how mass media content influences attitudes and behavior of audience members. To be fair, it is important to

Scott W. Campbell

26

Land mobile communications satellite  

NASA Astrophysics Data System (ADS)

The economic value and salient technical and operational characteristics of a European Land Mobile Communication Satellite (LMCS) to complement and supplement the demand for mobile services of Western European countries in the 1995 to 2005 time frames were assessed. A significant future expansion of demand for LCMS services on the part of the public is anticipated. Important augmentations of current service capabilities could be achieved by a satellite service, improving the overall system performances and/or assisting the PTT's in containing their investments in the required infrastructure. The satellite service itself could represent a profitable revenue producer.

Carnebianca, C.; Pavesi, B.; Tuozzi, A.

1986-09-01

27

A novel speech-like symbol design for data transmission through GSM voice channel  

Microsoft Academic Search

This paper introduces a new approach to design speech-like (SL) symbols in order to transmit digital data through global system for mobile communications (GSM) voice channel. Using these symbols leads to design a GSM voice channel data modem to modulate and demodulate data on enhanced full rate voice codec. Designing a set of time-symbols is an offline procedure with the

Ali Shahbazi; Amir Hossein Rezaie; Abolghasem Sayadiyan; Saeed Mosayyebpour

2009-01-01

28

A large-scale measurement of electromagnetic fields near GSM base stations in Guangxi, China for risk communication.  

PubMed

Radiofrequency (RF) electromagnetic field (EMF) exposure from wireless telecommunication base station antennae can lead to debates, conflicts or litigations among the adjacent residents if inappropriately managed. This paper presents a measurement campaign for the GSM band EMF exposure in the vicinity of 827 base station sites (totally 6207 measurement points) in Guangxi, China. Measurement specifications are designed for risk communication with the residents who previously complained of over-exposure. The EMF power densities with the global positioning system coordinate at each measured point were recorded. Compliance with the International Commission on Non-Ionizing Radiation Protection guidelines and Chinese environmental EMF safety standards was studied. The results show that the GSM band EMF level near the base stations is very low. The measurement results and the EMF risk communication procedures positively influence public perception of the RF EMF exposure from the base stations and promote the exchange of EMF exposure-related knowledge. PMID:23179188

Wu, Tongning; Shao, Qing; Yang, Lei; Qi, Dianyuan; Lin, Jun; Lin, Xiaojun; Yu, Zongying

2013-06-01

29

A smart bushfire monitoring and detection system using GSM technology  

Microsoft Academic Search

This paper describes a smart bushfire monitoring system that can provide an early warning message in case of a bushfire. The system utilises short message service through global system for mobile (GSM) communication technology as a medium of communication. The device is composed of a temperature and humidity sensors that are connected to a microcontroller. The microcontroller also interfaces with

Liu Liu; Rong Sun; Ying Sun; Said Al-Sarawi

2010-01-01

30

A -Enabled Mobile-TV RF Front-End With TV-GSM Interoperability in 1-V 90-nm CMOS  

Microsoft Academic Search

A 2 × VDD-enabled mobile-TV RF front-end with TV-GSM interoperability is described. It is an on\\/off-chip codesign employing externally three customized UHF\\/VHF preselect filters, an RF switch, and a balun. The integrated part includes: 1) a cascode-cascade inverter-based low-noise amplifier that features a high gain-to-power efficiency; 2) a linearized C-2C attenuator using reliably-overdriven MOS switches; 3) an inductive-peaking feedforward path

Pui-In Mak; Rui P. Martins

2010-01-01

31

Preattentive auditory information processing under exposure to the 902 MHz GSM mobile phone electromagnetic field: a mismatch negativity (MMN) study.  

PubMed

Previous studies on the effects of the mobile phone electromagnetic field (EMF) on various event-related potential (ERP) components have yielded inconsistent and even contradictory results, and often failed in replication. The mismatch negativity (MMN) is an auditory ERP component elicited by infrequent (deviant) stimuli differing in some physical features from the repetitive frequent (standard) stimuli in a sound sequence. The MMN provides a sensitive measure for cortical auditory stimulus feature discrimination, regardless of attention and other contaminating factors. In this study, MMN responses to duration, intensity, frequency, and gap changes were recorded in healthy young adults (n = 17), using a multifeature paradigm including several types of auditory change in the same stimulus sequence, while a GSM mobile phone was placed on either ear with the EMF (902 MHz pulsed at 217 Hz; SAR(1g) = 1.14 W/kg, SAR(10g) = 0.82 W/kg, peak value = 1.21 W/kg, measured with an SAM phantom) on or off. An MMN was elicited by all deviant types, while its amplitude and latency showed no significant differences due to EMF exposure for any deviant types. In the present study, we found no conclusive evidence that acute exposure to GSM mobile phone EMF affects cortical auditory change detection processing reflected by the MMN. PMID:19140136

Kwon, Myoung Soo; Kujala, Teija; Huotilainen, Minna; Shestakova, Anna; Näätänen, Risto; Hämäläinen, Heikki

2009-04-01

32

Design of a mobile telecardiology system using GPRS\\/GSM technology  

Microsoft Academic Search

This paper presents the design and development of a portable electrocardiograph to allow the on-line remote monitoring and real-time cardiac diseases diagnostics of patients from the specialist. This prototype has been satisfactory implemented finding a good balance between optimal signal processing and power consumption using a GPRS\\/GSM modem and a SMT low voltage microprocessor board.

M. Elena; J. M. Quero; C. L. Tarrida; L. G. Franquelo

2002-01-01

33

Secure Mobile IP Communication  

E-print Network

of Mobile IP & IPSec - 2 - #12;Integration of Mobile IP & IPSec - 3 - Table of contents: 1 ABSTRACT 5 2 Threats 13 3.2.2 Security Issues In Mobile IP 14 3.3 Security models 14 4 IPSEC OVERVIEW 16 4.1 Where does IPSec fit in? 16 4.2 Securing the IP layer 16 4.3 Security services offered by IPSec 17 4.3.1 Spoofing

Braun, Torsten

34

Prospects of GSM technology for academic library services  

Microsoft Academic Search

Purpose – Poor telecommunication infrastructure has been generally identified as a hindrance to most library activities in Nigeria. However, with the emergence and spread of wireless technologies, especially the global system of mobile communications (GSM), this paper seeks to consider the implications of this event on library services, with suggestions on the possible applications to academic libraries. Design\\/methodology\\/approach – A

Olayinka Catherine Fatoki

2005-01-01

35

Trends in mobile satellite communication  

NASA Technical Reports Server (NTRS)

Ever since the U.S. Federal Communication Commission opened the discussion on spectrum usage for personal handheld communication, the community of satellite manufacturers has been searching for an economically viable and technically feasible satellite mobile communication system. Hughes Aircraft Company and others have joined in providing proposals for such systems, ranging from low to medium to geosynchronous orbits. These proposals make it clear that the trend in mobile satellite communication is toward more sophisticated satellites with a large number of spot beams and onboard processing, providing worldwide interconnectivity. Recent Hughes studies indicate that from a cost standpoint the geosynchronous satellite (GEOS) is most economical, followed by the medium earth orbit satellite (MEOS) and then by the low earth orbit satellite (LEOS). From a system performance standpoint, this evaluation may be in reverse order, depending on how the public will react to speech delay and collision. This paper discusses the trends and various mobile satellite constellations in satellite communication under investigation. It considers the effect of orbital altitude and modulation/multiple access on the link and spacecraft design.

Johannsen, Klaus G.; Bowles, Mike W.; Milliken, Samuel; Cherrette, Alan R.; Busche, Gregory C.

1993-01-01

36

Electromagnetic interference to infusion pumps. Update2008 from GSM mobile phones.  

PubMed

Electromagnetic interference (EMI) to critical care medical devices has been reported by various groups. Previuos study demonstrated that infusion pumps are susceptible of false alarm buzzing and block of infusion, when exposed to various EMI sources. Aim of this paper is to investigate the changes in the risk of EMI from the estimates of our previous 2005 survey and to extend the EMI risk assessment to newer telecommunication products: DECT phones and WiFi terminals. With regards to GSM phones, compare to the results obtained in 2005, we observed a decrease in the rate of failure (from 58% to 30%). From our findings, the use of WiFi and DECT does not pose a real risk to infusion systems. PMID:19163716

Calcagnini, G; Censi, F; Triventi, M; Mattei, E; Losterzo, R; Marchetta, E; Bartolini, P

2008-01-01

37

The effects of 884 MHz GSM wireless communication signals on headache and other symptoms: an experimental provocation study.  

PubMed

Findings from prior studies of possible health and physiological effects from mobile phone use have been inconsistent. Exposure periods in provocation studies have been rather short and personal characteristics of the participants poorly defined. We studied the effect of radiofrequency field (RF) on self-reported symptoms and detection of fields after a prolonged exposure time and with a well defined study group including subjects reporting symptoms attributed to mobile phone use. The design was a double blind, cross-over provocation study testing a 3-h long GSM handset exposure versus sham. The study group was 71 subjects age 18-45, including 38 subjects reporting headache or vertigo in relation to mobile phone use (symptom group) and 33 non-symptomatic subjects. Symptoms were scored on a 7-point Likert scale before, after 1(1/2) and 2(3/4) h of exposure. Subjects reported their belief of actual exposure status. The results showed that headache was more commonly reported after RF exposure than sham, mainly due to an increase in the non-symptom group. Neither group could detect RF exposure better than by chance. A belief that the RF exposure had been active was associated with skin symptoms. The higher prevalence of headache in the non-symptom group towards the end of RF exposure justifies further investigation of possible physiological correlates. The current study indicates a need to better characterize study participants in mobile phone exposure studies and differences between symptom and non-symptom groups. PMID:18044740

Hillert, Lena; Akerstedt, Torbjörn; Lowden, Arne; Wiholm, Clairy; Kuster, Niels; Ebert, Sven; Boutry, Clementine; Moffat, Scott Douglas; Berg, Mats; Arnetz, Bengt Birger

2008-04-01

38

RFID and GSM Technology Building Intelligent Relief Supplies Distribution and Monitoring System  

Microsoft Academic Search

Taking advantage of the technology of wireless sensor networks (WSNs), the radio frequency identification (RFID) and global system for mobile communication(GSM), this paper constructs a wireless communication and intelligent application system. WSNs combines with RFID system collect basic materials property data, materials environmental data perceived by all kinds of sensors and materials coordinate information by satellite and global position system

Dongmei Huang; Cheng Su; Digou Fang; Peihong Kang

2010-01-01

39

Communications Systems for Mobile Robotics  

SciTech Connect

Performance Confirmation is the activity by which the Yucca Mountain Project confirms that the engineered and natural containment barriers of this national nuclear waste repository are performing as predicted, so that an eventual decision to close the repository can be made. This activity involves systems that must be inspected and, in some cases, serviced by mobile robots. This paper discusses systems for underground mobile robot communications, including requirements, environments, options, issues, and down-select criteria. We reviewed a variety of systems, including Slotted Waveguide, Powerline Carrier, Leaky Feeder, Photonic Bandgap Fiber, Free-Space Optics, Millimeter Waves, Terahertz Systems, and RF Systems (including IEEE 802.11 a,b, and g, and Ultra-Wideband radio).

Futterman, J A; Pao, H

2003-12-08

40

Application of Mobile Router to Military Communications.  

National Technical Information Service (NTIS)

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-r...

D. H. Stewart, W. D. Ivancic, T. L. Bell, B. A. Kachmar, D. Shell, K. Leung

2002-01-01

41

EFFECT OF GSM MOBILE PHONE RADIATION ON BLOOD-BRAIN BARRIER  

Microsoft Academic Search

Some animal studies have suggested that mobile phone radiation may cause increase in blood-brain barrier permeability. We have hypothesized (Leszczynski et al. Differentiation, 70, 2002, in press) that the mobile phone radiation-induced increased expression and phosphorylation (activity) of stress protein hsp27 might be the molecular mechanism regulating blood-brain barrier permeability and, possibly, cell apoptosis. Here we present evidence suggesting that

Dariusz Leszczynski

42

A review of mobile satellite communication systems  

NASA Astrophysics Data System (ADS)

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.

Kondo, Kimio

1990-03-01

43

Antennas for mobile satellite communications  

NASA Astrophysics Data System (ADS)

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.

Huang, John

1991-12-01

44

Antennas for mobile satellite communications  

NASA Technical Reports Server (NTRS)

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.

Huang, John

1991-01-01

45

Satellite communication and navigation for mobile users  

NASA Technical Reports Server (NTRS)

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.

Bernstein, S. L.

1972-01-01

46

GSM Cell Site Forensics  

Microsoft Academic Search

\\u000a Cell site forensics is a new and growing area of digital forensics, enabling investigators to verify a mobile phone subscriber’s\\u000a location at specific times. This paper focuses on cell site forensics in GSM networks. In particular, it discusses current\\u000a methods utilizing call detail records generated from telephone switches that provide information about cellular calls and\\u000a text messages, and the cellular

Christopher Swenson; Tyler Moore; Sujeet Shenoi

2006-01-01

47

Mobile Communications Device Allowances Frequently Asked Questions  

E-print Network

Mobile Communications Device Allowances Frequently Asked Questions Q: Why is NC State University-saving measure and to provide more flexibility for employees who must carry a mobile communications device education, state agencies, federal agencies, etc., as well as private corporations. Q: Why is my MCD

48

Experiment In Aeronautical-Mobile/Satellite Communication  

NASA Technical Reports Server (NTRS)

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).

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

1992-01-01

49

Reinventing Mobile Community Computing and Communication  

E-print Network

Networking Apps (SNAPPs) In our vision, mobile devices should become effective human assistants, reactingReinventing Mobile Community Computing and Communication (Position Paper) Yann Busnel, Nuno Cruz, smartphones and mobile applications spread like wildfire and dramatically improved aspects of our professional

Paris-Sud XI, Université de

50

Dosimetry in the human head for two types of mobile phone antennas at GSM frequencies  

NASA Astrophysics Data System (ADS)

In this paper, a comparative study of dipole and patch antennas commonly used in portable telephones is investigated. The two models antennas are considered working at 900, 1800 and 2450 MHz bands. Thus, we have included different distances between the mobile phone and the human head model. This study shows the effects of electromagnetic waves on the human head model. The objective is to evaluate the SAR in simulation anatomic based model of the human head for different antenna-head distances and in many frequencies. All numerical simulations results are performed using Ansoft HFSS software.

Karli, Radouane; Ammor, Hassan; Terhzaz, Jaouad

2014-03-01

51

Effective Protocols for Mobile Communications and Networking  

SciTech Connect

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.

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

1998-12-01

52

GSM SECURITY II Basar Kasim  

E-print Network

, transmission of signals through open-air, the requirement of low power consumption by mobile users and smaller areas and the requirement of low power consumption by the mobile users. This paper focuses on the GSM. This is mainly due to the fact that, the Elliptic Curve Cryptosystems provide the highest strength per-bit of any

Ertaull, Levent

53

Symmetrical analysis and evaluation of Differential Resistive Sensor output with GSM\\/GPRS network  

Microsoft Academic Search

Differential Resistive Sensor Interface is industrially significant for GSM\\/GPRS transmission to a mobile phone in order to enhance communication technique. The Sensor output needs to be made digital, hence the need for a microcontroller and the signal is displayed in a PC as output voltage, sensed parameter, x. A frequency and voltage output are obtained, showing how a small change

Deji Abdulwahab; Sheroz Khan; Jalel Chebil; A. H. M. Zahirul Alam

2011-01-01

54

Integrating GIS, GPS and GSM technologies for the effective management of ambulances  

Microsoft Academic Search

In this paper, we describe a system offering a solution to the problem of ambulance management and emergency incident handling in the prefecture of Attica in Greece. It is based on the integration of geographic information system (GIS), global positioning system (GPS) and global system for mobile communication (GSM) technologies. The design of the system was the result of a

G. Derekenaris; J. Garofalakis; C. Makris; J. Prentzas; S. Sioutas; A. Tsakalidis

2001-01-01

55

Subjective symptoms related to GSM radiation from mobile phone base stations: a cross-sectional study  

PubMed Central

Objectives We performed a re-analysis of the data from Navarro et al (2003) in which health symptoms related to microwave exposure from mobile phone base stations (BSs) were explored, including data obtained in a retrospective inquiry about fear of exposure from BSs. Design Cross-sectional study. Setting La Ńora (Murcia), Spain. Participants Participants with known illness in 2003 were subsequently disregarded: 88 participants instead of 101 (in 2003) were analysed. Since weather circumstances can influence exposure, we restricted data to measurements made under similar weather conditions. Outcomes and methods A statistical method indifferent to the assumption of normality was employed: namely, binary logistic regression for modelling a binary response (eg, suffering fatigue (1) or not (0)), and so exposure was introduced as a predictor variable. This analysis was carried out on a regular basis and bootstrapping (95% percentile method) was used to provide more accurate CIs. Results The symptoms most related to exposure were lack of appetite (OR=1.58, 95% CI 1.23 to 2.03); lack of concentration (OR=1.54, 95% CI 1.25 to 1.89); irritability (OR=1.51, 95% CI 1.23 to 1.85); and trouble sleeping (OR=1.49, 95% CI 1.20 to 1.84). Changes in –2 log likelihood showed similar results. Concerns about the BSs were strongly related with trouble sleeping (OR?=3.12, 95% CI 1.10 to 8.86). The exposure variable remained statistically significant in the multivariate analysis. The bootstrapped values were similar to asymptotic CIs. Conclusions This study confirms our preliminary results. We observed that the incidence of most of the symptoms was related to exposure levels—independently of the demographic variables and some possible risk factors. Concerns about adverse effects from exposure, despite being strongly related with sleep disturbances, do not influence the direct association between exposure and sleep. PMID:24381254

Gomez-Perretta, Claudio; Navarro, Enrique A; Segura, Jaume; Portoles, Manuel

2013-01-01

56

Mobile Perspectives: On Websites. Mobile Matters--Communication Trumps Technology  

ERIC Educational Resources Information Center

Mobile technology is a favorite discussion topic among senior IT leaders and higher education administrators. Mobile is the future for content delivery. Colleges and universities need to establish a strategy now and make the decisions necessary to take advantage of this communication opportunity. In this article, the author recommends making…

Evans, Susan T.

2011-01-01

57

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

Microsoft Academic Search

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

James E. Katz; Satomi Sugiyama

58

Mobile Communication Security Controllers An Evaluation Paper  

E-print Network

mobile handset is a ubiquitous part of modern life and as device technology and network performance investigates the suggestion. 1This has also extended into some regions using variants of CDMA standards where the RUIM is specified. V 1.01 1 #12;1 Introduction Mobile communication and computing technology have

Mayes, Keith

59

Presence and Embodiment in Mobile Phone Communication  

Microsoft Academic Search

This paper explores the temporal and spatial characteristics of mobile phone communication, comparing the experience of presence in phone calls and in virtual reality environments. It is argued that in phone communication interactional affordances create an experience of presence and a degree of embodiment. The theoretical framework adopted combines Goffman's frame analysis with Gibson's affordance theory and a situated cognition

Ruth M. Rettie

2005-01-01

60

USDA Forest Service mobile satellite communications applications  

NASA Technical Reports Server (NTRS)

The airborne IR signal processing system being developed will require the use of mobile satellite communications to achieve its full capability and improvement in delivery timeliness of processed IR data to the Fire Staff. There are numerous other beneficial uses, both during wildland fire management operations or in daily routine tasks, which will also benefit from the availability of reliable communications from remote areas.

Warren, John R.

1990-01-01

61

In vitro study of the stress response of human skin cells to GSM-1800 mobile phone signals compared to UVB radiation and heat shock.  

PubMed

The evolution of mobile phone technology is toward an increase of the carrier frequency up to 2.45 GHz. Absorption of radiofrequency (RF) radiation becomes more superficial as the frequency increases. This increasingly superficial absorption of RF radiation by the skin, which is the first organ exposed to RF radiation, may lead to stress responses in skin cells. We thus investigated the expression of three heat-shock proteins (HSP70, HSC70, HSP27) using immunohistochemistry and induction of apoptosis by flow cytometry on human primary keratinocytes and fibroblasts. A well-characterized exposure system, SXC 1800, built by the IT'IS foundation was used at 1800 MHz, with a 217 Hz modulation. We tested a 48-h exposure at an SAR of 2 W/kg (ICNIRP local exposure limit). Skin cells were also irradiated with a 600 mJ/cm2 single dose of UVB radiation and subjected to heat shock (45 degrees C, 20 min) as positive controls for apoptosis and HSP expression, respectively. The results showed no effect of a 48-h GSM-1800 exposure at 2 W/kg on either keratinocytes or fibroblasts, in contrast to UVB-radiation or heat-shock treatments, which injured cells. We thus conclude that the GSM-1800 signal does not act as a stress factor on human primary skin cells in vitro. PMID:17474794

Sanchez, S; Haro, E; Ruffié, G; Veyret, B; Lagroye, I

2007-05-01

62

Mobile satellite communications in the Forest Service  

NASA Technical Reports Server (NTRS)

There are usually some places within a forest that do not have adequate communication coverage due to line-of-sight or other reasons. These areas are generally known by the foresters and radio technicians and allowances are made for that when working or traveling in those areas. However, when wildfire or other emergencies occur, communications are vital because wildfires can require hundreds of firefighters and cover thousands of acres. During these emergency operations, the existing communications are not adequate and complete radio systems are moved into the area for the conduct of fire communications. Incident command posts (ICPs) and fire camps are set up in remote locations and there is constant need for communications in the fire area and to agency headquarters and dispatch offices. Mobile satellite communications would be an ideal supplement to the Forest Service's current communications system in aiding forest fire control activities.

Warren, John R.

1988-01-01

63

Mobile satellite communications in the Forest Service  

NASA Astrophysics Data System (ADS)

There are usually some places within a forest that do not have adequate communication coverage due to line-of-sight or other reasons. These areas are generally known by the foresters and radio technicians and allowances are made for that when working or traveling in those areas. However, when wildfire or other emergencies occur, communications are vital because wildfires can require hundreds of firefighters and cover thousands of acres. During these emergency operations, the existing communications are not adequate and complete radio systems are moved into the area for the conduct of fire communications. Incident command posts (ICPs) and fire camps are set up in remote locations and there is constant need for communications in the fire area and to agency headquarters and dispatch offices. Mobile satellite communications would be an ideal supplement to the Forest Service's current communications system in aiding forest fire control activities.

Warren, John R.

1988-05-01

64

A Mobile Multimedia Communication Framework for IP based Convergence Networks  

Microsoft Academic Search

We propose an efficient mobile multimedia communication protocol, mobile terminal software platform and mobile VoIP application for IP-based convergence networks. The proposed mobile multimedia communication protocol is called as ST-MRSVP (split tunnel based mobile resource reservation protocol) which integrates split tunnel based mobile IP and RSVP. Since mobile multimedia terminal platform should support seamless QoS level, mobile QoS modules for

Won-Tae Kim

2006-01-01

65

Implementation and analysis of integration GSM\\/GPRS modem in a TMS320VC6713 digital signal processor for vehicle location  

Microsoft Academic Search

The rapidly evolving wireless communications environment and 3G, where the standard are constantly created and modified, has given rise to the integration of GPS (Global Positioning System) and GSM (Global System for Mobile Communication). This integration has been widely applied in many disciplines including Intelligent Transportation System (ITS) and Logistic Management to aid the users to locate their vehicles remotely.

H. A. Rahim; R. B. Ahmad; A. S. M. Zain; U. U. Sheikh

2010-01-01

66

Pharos: coupling GSM and GPS-TALK technologies to provide orientation, navigation and location-based services for the blind  

Microsoft Academic Search

Millions of people are already experiencing with GSM the freedom of going mobile for voice and Internet access. This freedom is reshaping every aspect of our lives; the way we do business, the way we buy things and the way we communicate. For the blind, when combined with GPS, it could also add the freedom of movement. The paper considers

A. Marsh; M. May; M. Saarelainen

2000-01-01

67

Acute effects of electromagnetic fields emitted by GSM mobile phones on subjective well-being and physiological reactions: a meta-analysis.  

PubMed

The potential effects of radiofrequency electromagnetic fields (RF-EMF) emitted by GSM mobile phones on subjective symptoms, well-being and physiological parameters have been investigated in many studies. However, the results have been ambiguous. The current meta-analysis aims to clarify whether RF-EMF have an influence on well-being in self-reported sensitive persons, as well as in non-sensitive people. A literature search revealed 17 studies including 1174 participants. The single effects for various subjective and objective outcomes were meta-analytically combined to yield a single population parameter. Dependant variables were subjective (e.g. headaches) and objective parameters (e.g. heart rate variability) of well-being. The results show no significant impact of short-term RF-EMF exposure on any parameter. Future research should focus on the possible effects of long-term exposure. PMID:22421088

Augner, Christoph; Gnambs, Timo; Winker, Robert; Barth, Alfred

2012-05-01

68

Failure restoration of mobility databases for personal communication networks  

Microsoft Academic Search

This paper studies failure restoration of mobilitydatabases for personal communication networks(specifically, VLRs and HLRs). We model the VLRrestoration with and without checkpointing. The optimalVLR checkpointing interval is derived to balancethe checkpointing cost against the paging cost. Wealso model GSM periodic location updating (locationconfirmation) to quantify the relationship between thelocation confirmation frequency and the number oflost calls.The HLR failure restoration...

Yi-bing Lin

1995-01-01

69

Microstrip monopulse antenna for land mobile communications  

NASA Technical Reports Server (NTRS)

Low cost is one of the main requirements in a communication system suitable for mass production, as it is the case for satellite land mobile communications. Microstrip technology fulfills this requirement which must be supported by a low cost tracking system design. The tradeoff led us to a prototype antenna composed of microstrip patches based on electromechanical closed-loop principle; the design and the results obtained are described.

Garcia, Q.; Martin, C.; Delvalle, J. C.; Jongejans, A.; Rinous, P.; Travers, M. N.

1993-01-01

70

1. Final Title SECURITY of MOBILE COMMUNICATIONS  

E-print Network

limitations; c) the user requirements; d) the contents of provided services; and e) the evolution of hacking of security attacks and hacking techniques; 3) discussing security policies and security practices to help for hacking systems via mobile communications. Threats and risk analysis are discussed in this part, along

71

Multidimensional Human Dynamics in Mobile Phone Communications  

PubMed Central

In today's technology-assisted society, social interactions may be expressed through a variety of techno-communication channels, including online social networks, email and mobile phones (calls, text messages). Consequently, a clear grasp of human behavior through the diverse communication media is considered a key factor in understanding the formation of the today's information society. So far, all previous research on user communication behavior has focused on a sole communication activity. In this paper we move forward another step on this research path by performing a multidimensional study of human sociality as an expression of the use of mobile phones. The paper focuses on user temporal communication behavior in the interplay between the two complementary communication media, text messages and phone calls, that represent the bi-dimensional scenario of analysis. Our study provides a theoretical framework for analyzing multidimensional bursts as the most general burst category, that includes one-dimensional bursts as the simplest case, and offers empirical evidence of their nature by following the combined phone call/text message communication patterns of approximately one million people over three-month period. This quantitative approach enables the design of a generative model rooted in the three most significant features of the multidimensional burst - the number of dimensions, prevalence and interleaving degree - able to reproduce the main media usage attitude. The other findings of the paper include a novel multidimensional burst detection algorithm and an insight analysis of the human media selection process. PMID:25068479

Quadri, Christian; Zignani, Matteo; Capra, Lorenzo; Gaito, Sabrina; Rossi, Gian Paolo

2014-01-01

72

Multidimensional human dynamics in mobile phone communications.  

PubMed

In today's technology-assisted society, social interactions may be expressed through a variety of techno-communication channels, including online social networks, email and mobile phones (calls, text messages). Consequently, a clear grasp of human behavior through the diverse communication media is considered a key factor in understanding the formation of the today's information society. So far, all previous research on user communication behavior has focused on a sole communication activity. In this paper we move forward another step on this research path by performing a multidimensional study of human sociality as an expression of the use of mobile phones. The paper focuses on user temporal communication behavior in the interplay between the two complementary communication media, text messages and phone calls, that represent the bi-dimensional scenario of analysis. Our study provides a theoretical framework for analyzing multidimensional bursts as the most general burst category, that includes one-dimensional bursts as the simplest case, and offers empirical evidence of their nature by following the combined phone call/text message communication patterns of approximately one million people over three-month period. This quantitative approach enables the design of a generative model rooted in the three most significant features of the multidimensional burst - the number of dimensions, prevalence and interleaving degree - able to reproduce the main media usage attitude. The other findings of the paper include a novel multidimensional burst detection algorithm and an insight analysis of the human media selection process. PMID:25068479

Quadri, Christian; Zignani, Matteo; Capra, Lorenzo; Gaito, Sabrina; Rossi, Gian Paolo

2014-01-01

73

The evolution of global mobile communications  

NASA Astrophysics Data System (ADS)

A long term, global viewpoint is presented on the subject of communications access which may be the key to resolving many of the world's current requirements for developing a truly global, ubiquitous mobile/personal voice and data communications capability. The solutions are multi disciplinary, some using terrestrial techniques, some by satellite, but both using a variety of technologies and techniques. In the area of satellite communications, the focus is on inexpensive, efficient antennas, high gain spacecraft amplifiers and efficient power and bandwidth modulation techniques including high performance, low bit rate voice codecs. Terrestrially, many of the same technologies apply to cellular telephone systems. A key issue is the electromagnetic spectrum and its utilization efficiency, especially if the popularity of cellular telephones is repeated in the development of mobile satellite systems. Integration of diverse systems depends on formulating a framework that will allow systems to be interoperable by specifying logical interfaces among most or all evolving niche systems.

Spolsky, A. I.; Brasic, J. R.

74

Integration between terrestrial-based and satellite-based land mobile communications systems  

NASA Technical Reports Server (NTRS)

A survey is given of several approaches to improving the performance and marketability of mobile satellite systems (MSS). The provision of voice/data services in the future regional European Land Mobile Satellite System (LMSS), network integration between the Digital Cellular Mobile System (GSM) and LMSS, the identification of critical areas for the implementation of integrated GSM/LMSS areas, space segment scenarios, LMSS for digital trunked private mobile radio (PMR) services, and code division multiple access (CDMA) techniques for a terrestrial/satellite system are covered.

Arcidiancono, Antonio

1990-01-01

75

Radio Frequency Electromagnetic Radiation (RF-EMR) from GSM (0.9/1.8GHZ) Mobile Phones Induces Oxidative Stress and Reduces Sperm Motility in Rats  

PubMed Central

INTRODUCTION: Mobile phones have become indispensable in the daily lives of men and women around the globe. As cell phone use has become more widespread, concerns have mounted regarding the potentially harmful effects of RF-EMR from these devices. OBJECTIVE: The present study was designed to evaluate the effects of RF-EMR from mobile phones on free radical metabolism and sperm quality. MATERIALS AND METHODS: Male albino Wistar rats (10–12 weeks old) were exposed to RF-EMR from an active GSM (0.9/1.8 GHz) mobile phone for 1 hour continuously per day for 28 days. Controls were exposed to a mobile phone without a battery for the same period. The phone was kept in a cage with a wooden bottom in order to address concerns that the effects of exposure to the phone could be due to heat emitted by the phone rather than to RF-EMR alone. Animals were sacrificed 24 hours after the last exposure and tissues of interest were harvested. RESULTS: One hour of exposure to the phone did not significantly change facial temperature in either group of rats. No significant difference was observed in total sperm count between controls and RF-EMR exposed groups. However, rats exposed to RF-EMR exhibited a significantly reduced percentage of motile sperm. Moreover, RF-EMR exposure resulted in a significant increase in lipid peroxidation and low GSH content in the testis and epididymis. CONCLUSION: Given the results of the present study, we speculate that RF-EMR from mobile phones negatively affects semen quality and may impair male fertility. PMID:19578660

Mailankot, Maneesh; Kunnath, Anil P; Jayalekshmi, H; Koduru, Bhargav; Valsalan, Rohith

2009-01-01

76

Application of Mobile Router to Military Communications  

NASA Technical Reports Server (NTRS)

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 that resides in a network router. A Mobile-Router allows entire networks to roam while maintaining connectivity to the Internet. This router code is pertinent to a myriad of applications for both the government and commercial sectors. This technology will be applied to the wireless battlefield. NASA and the Department of Defense will utilize this technology for near-planetary observation and sensing spacecraft. It is the enabling technology for communication via the Internet or Intranets to aircraft. Information such as weather, air traffic control, voice and video can be easily and inexpensively transmitted to the aircraft using Internet protocols. The mobile router can be incorporated into emergency vehicles particularly ambulances and life-flight aircraft to provide real-time connectivity back to the hospital and healthcare experts. Commercial applications include entertainment services, IP telephone, and Internet connectivity for cruise ships, commercial shipping, tour busses, aircraft, and eventually cars. This paper will briefly describe the mobile router operation. An upcoming wide area network field test with application to US Coast Guard communications will be described. The paper will also highlight military and government networks that will benefit from the deployment of mobile router and the associated applications.

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

2002-01-01

77

Routing and Tracking System for Mobile Vehicles in Large Area  

Microsoft Academic Search

The paper describes a practical model for routing and tracking with mobile vehicle in a large area outdoor environment based on the Global Positioning System (GPS) and Global System for Mobile Communication (GSM). The supporting devices, GPS module-eMD3620 of AT&S company and GSM modem-GM862 of Telit company, are controlled by a 32bits microcontroller LM3S2965 implemented a new version ARM Cortex

Thuong Le-Tien; Vu Phung-The

2010-01-01

78

Connection Protocol For Mobile/Satellite Communications  

NASA Technical Reports Server (NTRS)

Throughput increased by better resolution of competing simultaneous requests for connections. Improved protocol sorts out simultaneous competing requests by message-originating stations for connection to satellite transmission link of land-mobile/satellite digital communication system. Applies to multiple-channel packet-message system with synchronous timeslots on all channels. Communication system has Q channels. Transmissions of packets allowed to begin only at beginnings of timeslots. Provides, to all users, binary feedback information on state of channel - namely, whether or not there is collision - during each timeslot.

Tan, Harry H.; Yan, Tsun-Yee

1990-01-01

79

Distributed Extremum Seeking and Cooperative Control for Mobile Communication  

E-print Network

Distributed Extremum Seeking and Cooperative Control for Mobile Communication Chaoyong Li, Zhihua of mobile cooperative communication clusters is considered. Each communication channel is modeled by its than a certain threshold. The objective of the communication network is to not only maintain

Ingram, Mary Ann

80

Acoustic energy conversion for mobile nanosensor network communication  

Microsoft Academic Search

Communication is fundamental capability of nanosesnor in medical and nanomedicine application. Communication by acoustic wave is most useful in nanosesnor mobile network. Acoustic communication between nanosensors in the mobile network has been favorable potential utilization in nanonmedicine, especially in health care, drug delivery and information processing. In this paper, we present the acoustic energy conversion between nanosensor communications that can

Mohammadjavad Abbasi Abandankeshi; Muhammad Shafie Abd Latiff

2011-01-01

81

A Secure Protocol for Traffic Police Mobile Communication System  

Microsoft Academic Search

The advance of wireless networking, communication, and mobile technology is making a big impact to daily life. Mobile devices, such as cell phones, and PDAs are becoming more popular each day. The large number of mobile users along with the ubiquitous nature of mobile devices has created a huge market for mobile applications and is caused a strong demand on

Habibollah Arasteh Rad; Khairulmizam Samsudin; A. R. B. Ramli; M. B. Tehrani; M. A. Tavalai

2009-01-01

82

A 2.7-4.5 V single chip GSM transceiver RF integrated circuit  

Microsoft Academic Search

This paper describes the design and implementation of a single-chip GSM (Global System for Mobile communications) transceiver RF integrated circuit. The chip includes the RF-to-baseband and baseband-to-RF (receive and transmit) functions, two fixed frequency PLL's, and a programmable frequency agile UHF synthesizer. It is implemented In a 1.5 ?m silicon bipolar process with 12 GHz NPN's and 110 MHz lateral

Trudy D. Stetzler; Irving G. Post; Joseph H. Havens; Mikio Koyama

1995-01-01

83

MOBILITY, MEDIA, AND EVERYDAY LIFE - AN INTERDISZIPLINARY FRAMEWORK FOR COMMUNICATIONS  

Microsoft Academic Search

Communication technologies have become a natural and important part of people's everyday life. Since mobile media have the potential to accompany its user everywhere, they can be part of almost every situation. For that reason communication research should focus on the impact mobile media usage has on existing (media) situations or formulated as a research question: How do mobile media

Christine Dietmar; Georg F. Kircher; Isabel Schlote

84

The Role of Innovation Regimes and Policy for Creating Radical Innovations: Comparing Some Aspects of Fuel Cells and Hydrogen Technology Development with the Development of Internet and GSM  

ERIC Educational Resources Information Center

Telegraphy, the distant ancestor of Internet and GSM (Global System for Mobile Communications), was invented by Samuel Morse in 1838. One year later, William Grove invented the fuel cell. Although numerous highly successful innovations stemming from telegraphy may be observed, the development of fuel cells has been insignificant, slow, and erratic…

Godoe, Helge

2006-01-01

85

Hybrid Mobile Communication Networks for Planetary Exploration  

NASA Technical Reports Server (NTRS)

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.

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

2007-01-01

86

A Pattern Language for Mobility Management  

Microsoft Academic Search

The different mobile wireless communication systems that are currently available adopt common solutions for dealing with recurring mobility management problems associated with similar architectural elements. This work extracts and documents patterns that identify such common problems and solutions among second generation systems, for example, GSM-900 and D-AMPS. These patterns are grouped into a pattern language that shows how they interact.

Rossana Andrade; Luigi Logrippo; Mark Bottomley; Todd Coram

2000-01-01

87

A mobility-aware dynamic database caching scheme for wireless mobile computing and communications  

Microsoft Academic Search

This paper describes a mobility-aware dynamic database caching scheme for wireless mobile computing and communications. A mobile-floating agent scheme is proposed, in which:caching techniques are cognizant of the mobile nature of mobile users and the location-sensitive nature of mobile systems. The mobile-floating agent maintains a second class cache in the fixed network and employs Barbara's ''invalidation reports broadcasting'' cache consistency

George Y. Liu

1996-01-01

88

Personal Mobility in the ICEBERG Integrated Communication Network  

E-print Network

Personal Mobility in the ICEBERG Integrated Communication Network Bhaskaran Raman bhaskar communication services in a personalized, unified, and clean fashion across these devices. The Iceberg Project as defined by Iceberg are much richer than the corresponding concepts in traditional telephony

Raman, Bhaskaran

89

Increased blood–brain barrier permeability in mammalian brain 7 days after exposure to the radiation from a GSM900 mobile phone  

Microsoft Academic Search

Microwaves were for the first time produced by humans in 1886 when radio waves were broadcasted and received. Until then microwaves had only existed as a part of the cosmic background radiation since the birth of universe. By the following utilization of microwaves in telegraph communication, radars, television and above all, in the modern mobile phone technology, mankind is today

Henrietta Nittby; Arne Brun; Jacob Eberhardt; Lars Malmgren; Bertil R. R. Persson; Leif G. Salford

2009-01-01

90

MobileMiner: A Real World Case Study of Data Mining in Mobile Communication  

E-print Network

MobileMiner: A Real World Case Study of Data Mining in Mobile Communication Tengjiao Wang , Bishan Confidence Software Technologies (Peking University), Ministry of Education, China School of Electronics@cs.sfu.ca ABSTRACT Mobile communication data analysis has been often used as a background application to motivate

Pei, Jian

91

The Impact of Avatar Mobility on Distributed Server Assignment for Delivering Mobile Immersive Communication Environment  

Microsoft Academic Search

In our previous work, we proposed a distributed server architecture to deliver multi-party immersive voice communication service to mobile clients (e.g. Sony PSP) accessing a distributed virtual environment (DVE). We refer to such immersive voice communication service as mobile immersive communication environment (MICE). We also proposed solutions to assign server to create the auditory scene for each avatar. In this

Ying Peng Que; Farzad Safaei; Paul Boustead

2007-01-01

92

Does exposure to GSM 900 MHz mobile phone radiation affect short-term memory of elementary school students?  

PubMed Central

Background: Now-a-days, children are exposed to mobile phone radiation at a very early age. We have previously shown that a large proportion of children in the city of Shiraz, Iran use mobile phones. Furthermore, we have indicated that the visual reaction time (VRT) of university students was significantly affected by a 10 min real/sham exposure to electromagnetic fields emitted by mobile phone. We found that these exposures decreased the reaction time which might lead to a better response to different hazards. We have also revealed that occupational exposures to radar radiations decreased the reaction time in radar workers. The purpose of this study was to investigate whether short-term exposure of elementary school students to radiofrequency (RF) radiation leads to changes in their reaction time and short-term memory. Materials and Methods: A total of 60 elementary school children ages ranging from 8 to 10 years studying at a public elementary school in Shiraz, Iran were enrolled in this study. Standardized computer-based tests of VRT and short-term memory (modified for children) were administered. The students were asked to perform some preliminary tests for orientation with the VRT test. After orientation, to reduce the random variation of measurements, each test was repeated ten times in both real and sham exposure phases. The time interval between the two subsequent sham and real exposure phases was 30 min. Results: The mean ± standard deviation reaction times after a 10 min talk period and after a 10 min sham exposure (switched off mobile) period were 249.0 ± 82.3 ms and 252.9 ± 68.2 ms (P = 0.629), respectively. On the other hand, the mean short-term memory scores after the talk and sham exposure periods were 1062.60 ± 305.39, and 1003.84 ± 339.68 (P = 0.030), respectively. Conclusion: To the best of our knowledge, this is the first study to show that short-term exposure of elementary school students to RF radiation leads to the better performance of their short-term memory. PMID:25250064

Movvahedi, M. M.; Tavakkoli-Golpayegani, A.; Mortazavi, S. A. R.; Haghani, M.; Razi, Z.; Shojaie-fard, M. B.; Zare, M.; Mina, E.; Mansourabadi, L.; Nazari-Jahromi; Safari, A.; Shokrpour, N.; Mortazavi, S. M. J.

2014-01-01

93

Measurement and analysis of electromagnetic pollution generated by GSM-900 mobile phone networks in Erciyes University, Turkey.  

PubMed

Mobile phones are becoming increasingly important in our everyday lives. The rising number of mobile phones reflects a similar increase in the number of base stations. Because of this rapid evolution, the establishment and planning of new base stations has become mandatory. However, the rise in the number of base stations, in terms of human health, is potentially very harmful. It is important to analyze the radiation levels of base stations until we can confirm that they are definitely not harmful in the long term. Mapping of electromagnetic field (EMF) is also important from a medical point of view because it provides useful information, for example, on the detection of diseases caused by EMF. With the help of this information the distribution of diseases over different regions can be obtained. In this article, the electromagnetic radiation levels of base stations were measured at 80 different points in Erciyes University (ERU), Turkey and detailed information about the measurement tools and measurement method were given. It was observed that no area in ERU exceeded the national and international limits. It is also observed that the effects of base stations vary according to duration and degree of exposure. Therefore, if people are exposed to a very low-intensity electromagnetic field for a very long time, serious health problems can occur. PMID:22676177

Sorgucu, Ugur; Develi, Ibrahim

2012-12-01

94

Land vehicle antennas for satellite mobile communications  

NASA Technical Reports Server (NTRS)

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.

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

1985-01-01

95

Learning significant user locations with GPS and GSM  

E-print Network

This thesis addresses the tasks of place discovery and place recognition - learning and recognizing places significant to a user - by analyzing GPS location and GSM cell tower data collected from the user's mobile phone. ...

Yu, Xiao, M. Eng. Massachusetts Institute of Technology

2006-01-01

96

Lightweight Client-Pull Protocol for Mobile Communication  

Microsoft Academic Search

Consumer mobile devices, such as cellular phones and PDAs, rely on TCP\\/IP as main communication pro- tocol. However, cellular networks are not reliable as wired and wireless LAN, due to both users mobility and geographical obstacles. Moreover, limited bandwidth outside urban areas requires an application level data priority management, in order to improve user experience and avoid communication stack deadlocks.

Stefano Sanna; Emanuela De Vita; Andrea Piras; Christian Melchiorre

2005-01-01

97

Key Technologies for IMT-Advanced Mobile Communication Systems  

E-print Network

Key Technologies for IMT-Advanced Mobile Communication Systems Carl WIJTING1 , Klaus DOPPLER1 and assessment of key technologies for IMT-Advanced mobile communication systems. WINNER has devised an OFDMA- Advanced technology proposals has been issued by the International Telecommunication Union (ITU) [2

98

SIMKEYS: an efficient approach in text entry for mobile communications  

Microsoft Academic Search

As text messaging services are becoming increasingly popular in today's global wireless market, fundamental design issues still linger with respect to text entry methods on mobile devices. Current schemes are often plagued with problems, such as poor typing efficiency, stringent physical size limitations, and unwarranted cognitive processing burden, on mobile users. The proposed text entry scheme for mobile communications, called

Rick W. K. Ha; Pin-Han Ho; X. Sherman Shen

2004-01-01

99

Protocol Design for Mobile Radio Group Communications Over Satellite  

Microsoft Academic Search

A protocol design for a mobile radio service supporting half-duplex push-to-talk voice communications over mobile satellite systems is presented. The service enables a closed group of mobile radio users to communicate among themselves, so that a transmission from any user is received by all. A key issue is the efficient utilization of satellite channels. Demand-assignment multiple access (DAMA) is employed

Victor C. M. Leung

1992-01-01

100

Precise design technique for a SAW-resonator-coupled filter on 36° YX-LiTaO3 for use in a GSM SAW duplexer module for satisfying all GSM system specifications  

Microsoft Academic Search

A miniature low-loss high-performance surface acoustic wave (SAW) duplexer module consisting of a receiver top filter (R1), transmitter final stage filter (T1), lumped matching-circuit elements and lumped phase-shift circuits has been developed, and its use in the Global System for Mobile Communication (GSM) is described as a design example. The complete duplexer module has an insertion loss of less than

N. Shibagaki; K. Sakiyama; M. Hikita

1996-01-01

101

Mocotos: Mobile Communications Tools for Children with Special Needs  

E-print Network

in communication and social interaction. Children with autism typically do not acquire verbal and social skillsMocotos: Mobile Communications Tools for Children with Special Needs Abstract Children with special needs often struggle to communicate about even the most basic of concepts. For children who cannot

Hayes, Gillian R.

102

Personal Mobility in the ICEBERG Integrated Communication Network  

E-print Network

Personal Mobility in the ICEBERG Integrated Communication Network Bhaskaran Raman Randy H. Katz in the ICEBERG Integrated Communication Network Bhaskaran Raman Randy H. Katz Anthony D. Joseph fbhaskar communication services in a personalized, unified, and clean fashion across these devices. The Iceberg Project

Joseph, Anthony D.

103

Mobile Computing and Communications: An Introduction  

Microsoft Academic Search

This paper gives an overview of mobile computing and issues related to the field. The discussion starts with definitions of various terms associated with mobile computing. The diversity of mobile applications is explored to give readers an idea of what mobile computing has to offer, followed by a discussion on the limitations of wireless networks and the issues which have

Mazliza Othman; Fakulti Sains Komputer; Teknologi Maklumat

1999-01-01

104

Mobile communications satellite antenna flight experiment definition  

NASA Astrophysics Data System (ADS)

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.

Freeland, Robert E.

105

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

Julien INC2004INC2004 Seamless Communications for Mobile Emergency ServicesSeamless Communications for Mobile Emergency Services Seamless Communications for MobileSeamless Communications for Mobile Emergency ServicesEmergency2004 Seamless Communications for Mobile Emergency ServicesSeamless Communications for Mobile Emergency

Abu-Rgheff, Mosa Ali

106

Inferring human mobility using communication patterns  

E-print Network

Understanding the patterns of mobility of individuals is crucial for a number of reasons, from city planning to disaster management. There are two common ways of quantifying the amount of travel between locations: by direct observations that often involve privacy issues, e.g., tracking mobile phone locations, or by estimations from models. Typically, such models build on accurate knowledge of the population size at each location. However, when this information is not readily available, their applicability is rather limited. As mobile phones are ubiquitous, our aim is to investigate if mobility patterns can be inferred from aggregated mobile phone call data. Using data released by Orange for Ivory Coast, we show that human mobility is well predicted by a simple model based on the frequency of mobile phone calls between two locations and their geographical distance. We argue that the strength of the model comes from directly incorporating the social dimension of mobility. Furthermore, as only aggregated call da...

Palchykov, Vasyl; Jo, Hang-Hyun; Saramäki, Jari; Pan, Raj Kumar

2014-01-01

107

Podscanning : audio microcontent and synchronous communication for mobile devices  

E-print Network

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 ...

Wheeler, Patrick Sean

2010-01-01

108

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

E-print Network

of wireless communications Cellular wireless networks 2G, 2.5G, 3G and 4G, ... cellular networks Mobility. Glisic, Advanced Wireless Networks: 4G Technologies, 2 ed. Wiley, 2009. #12;Outline-10 Course Materials

Pulfrey, David L.

109

Evaluation of Mobile Communications: From Voice Calls to Ubiquitous Multimedia Group Communications  

E-print Network

systems, namely the coexistence of heterogeneous mobile networks, and the migration to B3G systems. #12;IVIV1/1 Evaluation of Mobile Communications: From Voice Calls to Ubiquitous Multimedia Group in terms of network heterogeneity, migration to B3G, mobility over heterogeneous networks, and real

Monteiro, Edmundo

110

IEEE Communications Magazine July 2002108 Standardization of Mobile Phone  

E-print Network

-based services. For instance, the telematics system [1] currently offered by automotive manufacturers, such as GM Systems 0163-6804/02/$17.00 © 2002 IEEE ABSTRACT Finding the location of the mobile phone is one of the important features of the 3G mobile communication system. Many valuable location- based services can

Han, Richard Y.

111

Cooperation without (reliable) communication: Interfaces for mobile applications  

Microsoft Academic Search

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

Alan J. Dix

1995-01-01

112

Mobile Router Testing with Diverse RF Communications Links  

NASA Technical Reports Server (NTRS)

This is a short report on demonstrations using Mobile IP and several diverse physical communications links to connect a mobile network to a fixed IPv4 internet. The first section is a description of the equipment used, followed by descriptions of the tests, the theoretical results, and finally conclusions and the actual data.

Brooks, David; Hoder, Doug; Wilkins, Ryan

2004-01-01

113

The History of LandMobile Radio Communications  

Microsoft Academic Search

This paper on land-mobile radio communications was prepared for the noncommunications and nonmobile radio specialist. The early pioneering work of the police is covered, and after a brief statement about the early use of mobile transmitters, the Connecticut State Police two-way FM system is described. From the introduction of FM into the Connecticut system to the present, engineering efforts have

Daniel Noble

1962-01-01

114

New inclined synchronous satellite system for mobile communications and radiodetermination  

Microsoft Academic Search

A new satellite system using inclined synchronous satellites is proposed. This system can provide radiodetermination services as well as communication services for mobile earth stations in the common satellite system. In this system, two or more satellites can be always observed at the same time from any mobile terminal on the earth (including the polar regions) with an elevation angle

Fumiaki Sugaya; Yutaka Yasuda; Yasuo Hirata

1988-01-01

115

RadioActive: Enabling Persistent Mobile Communications for Groups  

E-print Network

effective than text in group collaboration because of its ability to promote higher level and more social1 RadioActive: Enabling Persistent Mobile Communications for Groups Abstract Current mobile technology works well to connect individuals together at any time or place. However, general focus on one

116

Usability of a mobile, group communication prototype while rendezvousing  

Microsoft Academic Search

Mobile phones are increasingly being used collaboratively by social networks of users in spite of the fact that they are primarily designed to support single users and one-to-one communication. It is not well understood how services such as group SMS, SMS-based discussion lists and mobile instant messaging (IM) will be used by mobile groups in natural settings. Studying specific instances

Jeff Axup; Stephen Viller; Nicola J Bidwell

2005-01-01

117

Influence of new mobile tools on communication  

Microsoft Academic Search

With the advent of such new communication tools as cellular phones and the Internet, communication styles have diversified. This diversity has brought changes in community formation as well as such serious problems as network addiction and mutual distrust among users. The purpose of this study is to find clues to these problems produced by those new communication tools. Thus, we

Saori Murata; Fujio Toriumi; Kenichiro Ishii

118

Effect of MobileASL on Communication Among Deaf Users  

E-print Network

using the encoding software library x264 [7]. Our goal is to make ASL cell phone communication possible and the slow processor speeds on cell phones. A new real-time compression scheme is needed to transmit video to mobile use. Video cell phones would allow Deaf people to communicate in real-time using sign language

Wobbrock, Jacob O.

119

Intercepting Mobile Communications: The Insecurity of 802.11  

E-print Network

Intercepting Mobile Communications: The Insecurity of 802.11 Nikita Borisov UC Berkeley nikitab be derived from the WEP insecurities. Finally, Section 7 offers some conclusions. 2. THE WEP PROTOCOL the communicating parties to protect the body of a transmitted frame of data. Encryp­ tion of a frame proceeds

Wagner, David

120

Intercepting Mobile Communications: The Insecurity of 802.11  

E-print Network

Intercepting Mobile Communications: The Insecurity of 802.11 Nikita Borisov UC Berkeley nikitab 6 suggest some general lessons that can be derived from the WEP insecurities. Finally, Section 7 relies on a secret key ÂŁ shared between the communicating parties to protect the body of a transmitted

Sirer, Emin Gun

121

Intercepting Mobile Communications: The Insecurity of 802.11  

E-print Network

Intercepting Mobile Communications: The Insecurity of 802.11 Nikita Borisov UC Berkeley nikitab be derived from the WEP insecurities. Finally, Section 7 offers some conclusions. 2. THE WEP PROTOCOL the communicating parties to protect the body of a transmitted frame of data. Encryp- tion of a frame proceeds

Han, Richard Y.

122

Accountable Anonymous Service Usage in Mobile Communication Systems \\Lambda  

E-print Network

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 communication systems. This model is based on the introduction of a new business role, called the customer care

Bencsáth, Boldizsár

123

Optimization of Wireless Resources for Personal Communications Mobility Tracking  

Microsoft Academic Search

In personal communications applications, users communicate via wireless with a wireline net- work. The wireline network tracks the current location of the user, and can therefore route mes- sages to a user regardless of the user's location. In addition to its impact on signaling within the wireline network, mobility tracking requires the expenditure of wireless resources as well, includ- ing

Upamanyu Madhow; Michael L. Honig; Kenneth Steiglitz

1994-01-01

124

Multifunction personal and mobile SMM antenna for satellite communications systems  

Microsoft Academic Search

There are a number of personal and mobile communications systems based on the use of microwave links relayed by Earth-orbiting satellites between small, low-cost Earth terminals using antennas of low directivity and broad beam aiming at the appropriate satellites. These satellite communications systems are now either deployed or in various stages of development and planning. For example, there are the

J. J. H. Wang; J. K. Tillery

1997-01-01

125

Coded Modulations for Mobile Satellite Communication Channels  

NASA Astrophysics Data System (ADS)

The mobile satellite (MSAT) channel is subject to multipath fading, shadowing, Doppler frequency shift, and adjacent channel interference (ACI). Therefore, transmitted signals face severe amplitude and phase distortions. This dissertation investigates various high performance and low decoding complexity coded modulation schemes for reliable voice and data transmissions over the shadowed mobile satellite channel and the Rayleigh fading channel. The dissertation consists of four parts. The first part presents a systematic technique for constructing MPSK trellis coded modulation (TCM) codes for voice transmission over the MSAT channel. The multilevel coding method is used for constructing TCM codes using convolutional codes with good free branch distances as the component codes or using both convolutional and block codes as the component codes. Simulation results show that these codes achieve good coding gains over the uncoded reference system and outperform existing TCM codes with the same decoding complexity. In the second part, using the multilevel coding method, multilevel block coded modulation (BCM) codes are constructed for voice transmission over the MSAT channel. Even though BCM is generally less power efficient than TCM for AWGN channels, BCM has a great potential to compete with TCM in the MSAT channel because of its shorter decoding depth and hence more effective interleaving. Binary Reed -Muller (RM) codes of length up to 32 are used as component codes. Simulation results show that these codes achieve good coding gains over the uncoded reference system and outperform TCM codes with the same decoding complexity. In the third part, a simple and systematic technique for constructing multilevel concatenated BCM schemes for data transmission over the shadowed MSAT channel and the Rayleigh fading channel is presented. These schemes are designed to achieve high-performance or large coding gain with reduced decoding complexity. Construction is based on a multilevel concatenation approach in which long powerful (binary or non-binary) codes are used as the outer codes and coset codes constructed from a linear BCM code and its subcodes are used as the inner codes. Simulation results show that these codes achieve large coding gains over the uncoded reference system and outperform single-level concatenated BCM codes with the same inner codes. Especially, some multilevel concatenated BCM codes achieve an error-floor free communication at BER of 10^{-5 }. In the final part of the dissertation, product coded modulation schemes are constructed by using multilevel concatenating approach. In product coded modulation, the product coding technique and coded modulation are combined to achieve high performance with reduced decoding complexity. Good product 8-PSK modulation codes are constructed for various shadowed MSAT channels. Simulation results show that these codes achieve large coding gains over the uncoded reference system and outperform single-level concatenated BCM codes with the same inner codes.

Rhee, Dojun

1995-01-01

126

77 FR 35336 - Privacy and Security of Information Stored on Mobile Communications Devices  

Federal Register 2010, 2011, 2012, 2013

...of Information Stored on Mobile Communications Devices...data security practices of mobile wireless services providers...stored on their users' mobile communications devices...FCC504@fcc.gov or phone: 202-418- 0530 or...

2012-06-13

127

Inferring human mobility using communication patterns  

NASA Astrophysics Data System (ADS)

Understanding the patterns of mobility of individuals is crucial for a number of reasons, from city planning to disaster management. There are two common ways of quantifying the amount of travel between locations: by direct observations that often involve privacy issues, e.g., tracking mobile phone locations, or by estimations from models. Typically, such models build on accurate knowledge of the population size at each location. However, when this information is not readily available, their applicability is rather limited. As mobile phones are ubiquitous, our aim is to investigate if mobility patterns can be inferred from aggregated mobile phone call data alone. Using data released by Orange for Ivory Coast, we show that human mobility is well predicted by a simple model based on the frequency of mobile phone calls between two locations and their geographical distance. We argue that the strength of the model comes from directly incorporating the social dimension of mobility. Furthermore, as only aggregated call data is required, the model helps to avoid potential privacy problems.

Palchykov, Vasyl; Mitrovi?, Marija; Jo, Hang-Hyun; Saramäki, Jari; Pan, Raj Kumar

2014-08-01

128

Frontiers of Wireless and Mobile Communications  

E-print Network

because of the popularity of Internet applications on mass-market mobile platforms including smart phones Internet based. By Dipankar Raychaudhuri, Fellow IEEE, and Narayan B. Mandayam, Fellow IEEE ABSTRACT applications as they migrate to mobile Internet platforms. KEYWORDS | Ad hoc and mesh networks; audiovisual

Mandayam, Narayan

129

Presence Aware Location-Based Service For Managing Mobile Communications  

Microsoft Academic Search

Presence technology based on Session Initiation Protocol can be used as an enabling platform for delivering communication and providing event-based services. We present a mobile workforce management solution which integrates fleet management with presence-based communication to show how presence technology can be used to realize location-based communication services. In particular, our solution integrates a user's presence information with their vehicle's

Vishal Kumar Singh; Henning Schulzrinne; Piotr Boni; Boris Elman; David Kenneson

2007-01-01

130

Design of Hybrid Mobile Communication Networks for Planetary Exploration  

NASA Technical Reports Server (NTRS)

The Mobile Exploration System Project (MEX) at NASA Ames Research Center has been conducting studies into hybrid communication networks for future planetary missions. These networks consist of space-based communication assets connected to ground-based Internets and planetary surface-based mobile wireless networks. These hybrid mobile networks have been deployed in rugged field locations in the American desert and the Canadian arctic for support of science and simulation activities on at least six occasions. This work has been conducted over the past five years resulting in evolving architectural complexity, improved component characteristics and better analysis and test methods. A rich set of data and techniques have resulted from the development and field testing of the communication network during field expeditions such as the Haughton Mars Project and NASA Mobile Agents Project.

Alena, Richard L.; Ossenfort, John; Lee, Charles; Walker, Edward; Stone, Thom

2004-01-01

131

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

NASA Astrophysics Data System (ADS)

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.

1985-12-01

132

FOREST OPERATIONS MANAGEMENT: TOWARDS MOBILE COMMUNICATION  

Microsoft Academic Search

Large worldwide operating forest industry companies use modern information and communication technology (ICT) in forest operations management nowadays. Many of the smaller companies are introducing these systems as well. The necessary condition for the use of these systems is a well developed communication infrastructure of the country. Similar systems are applied elsewhere, too, but they may not be as sophisticated

Esko Mikkonen

133

Increasing clinical presence of mobile communication technology: avoiding the pitfalls.  

PubMed

Mobile communication technologies are employed in many diverse areas of healthcare delivery to provide improved quality and efficiency of communication and facilitate increased rapidity of data or information transfer. Mobile phones enable healthcare professionals to possess a portable platform from which to provide many healthcare-related applications and are a popular means to directly communicate with colleagues and patients. As involvement of mobile communication technology in healthcare delivery continues to rapidly expand, there are also important considerations of relevance to patient safety and security as a result. Here, we review the previous evidence of reported clinical risks associated with mobile communication technology, such as electromagnetic interference, confidentiality and data security, distraction/noise, infection control, and cross contamination. In conclusion, although mobile phones provide much putative potential improvement to healthcare delivery, further evaluation and research are required to both inform and protect health professionals and users of such technology in the healthcare environment and provide the evidence base to support the provision of clear and comprehensive guidelines. PMID:21780941

Visvanathan, Akila; Gibb, Alan P; Brady, Richard R W

2011-10-01

134

A Silicon Germanium, High Efficiency Power Amplifier Chipset for GSM\\/DCS-PCS\\/WCDMA Handset Applications  

Microsoft Academic Search

A power amplifier chipset for GSM and WCDMA mobile handset PAs has been designed and fabricated in the IBM Silicon Germanium BiCMOS 5AM process. This 3-chip set offers competitive performance and reliability for integrated GSM\\/DCS-PCS\\/WCDMA applications. The constant envelope (GSM and DCS-PCS) power amplifier designs are optimized for efficiency under pulsed GMSK conditions, achieving 55% and 45% PAE at 900

Joe Pusl; Srikanth Sridharan; David Helms; Philip Antognetti; Mark Doherty

2001-01-01

135

An improved procedure to accurately assess the variability of the exposure to electromagnetic radiation emitted by GSM base station antennas  

NASA Astrophysics Data System (ADS)

Long-term human exposure around Global System for Mobile Communications (GSM) base station antennas has not yet been precisely established; this is of interest from human health and epidemiological perspectives. Actual exposure is difficult to assess accurately, mainly because there is a lack of technical information directly from the GSM operators. The in situ measurement standards available at present provide only a worst-case prediction method; the present work goes beyond this and proposes a methodology that, without the need for data from operators, allows a reliable way to express real exposure with a greater accuracy than all other methods proposed to date. The method is based on dual measurements of the signal strengths in the frequency domain and the time domain and takes into consideration the instantaneous traffic in GSM channels. In addition, it allows a channel-individualized exposure assessement, by making possible the separate analysis of the electric field level in the two types of channel of the GSM standard—the traffic channels and the control channels.

Bechet, Paul; Miclaus, Simona

2013-01-01

136

Looking at the other side of the coin: the search for possible biopositive cognitive effects of the exposure to 900 MHz GSM mobile phone radiofrequency radiation  

PubMed Central

Although exposure to electromagnetic radiation in radiofrequency range has caused a great deal of concern globally, radiofrequency radiation has many critical applications in both telecommunication and non-communication fields. The induction of adaptive response phenomena by exposure to radiofrequency radiation as either increased resistance to a subsequent dose of ionizing radiation or resistance to a bacterial infection has been reported recently. Interestingly, the potential beneficial effects of mobile phone radiofrequency radiation are not only limited to the induction of adaptive phenomena. It has previously been indicated that the visual reaction time of university students significantly decreased after a 10 min exposure to radiofrequency radiation emitted by a mobile phone. Furthermore, it has been revealed that occupational exposures to radar radiations decreased the reaction time in radar workers. Based on these findings, it can be hypothesized that in special circumstances, these exposures might lead to a better response of humans to different hazards. Other investigators have also provided evidence that confirms the induction of RF-induced cognitive benefits. Furthermore, some recent reports have indicated that RF radiation may play a role in protecting against cognitive impairment in Alzheimer’s disease. In this light, a challenging issue will arise if there are other RF-induced stimulating effects. It is also challenging to explore the potential applications of these effects. Further research may shed light on dark areas of the health effects of short and long-term human exposure to radiofrequency radiation. PMID:24843789

2014-01-01

137

Looking at the other side of the coin: the search for possible biopositive cognitive effects of the exposure to 900 MHz GSM mobile phone radiofrequency radiation.  

PubMed

Although exposure to electromagnetic radiation in radiofrequency range has caused a great deal of concern globally, radiofrequency radiation has many critical applications in both telecommunication and non-communication fields. The induction of adaptive response phenomena by exposure to radiofrequency radiation as either increased resistance to a subsequent dose of ionizing radiation or resistance to a bacterial infection has been reported recently. Interestingly, the potential beneficial effects of mobile phone radiofrequency radiation are not only limited to the induction of adaptive phenomena. It has previously been indicated that the visual reaction time of university students significantly decreased after a 10 min exposure to radiofrequency radiation emitted by a mobile phone. Furthermore, it has been revealed that occupational exposures to radar radiations decreased the reaction time in radar workers. Based on these findings, it can be hypothesized that in special circumstances, these exposures might lead to a better response of humans to different hazards. Other investigators have also provided evidence that confirms the induction of RF-induced cognitive benefits. Furthermore, some recent reports have indicated that RF radiation may play a role in protecting against cognitive impairment in Alzheimer's disease. In this light, a challenging issue will arise if there are other RF-induced stimulating effects. It is also challenging to explore the potential applications of these effects. Further research may shed light on dark areas of the health effects of short and long-term human exposure to radiofrequency radiation. PMID:24843789

Mortazavi, Seyed Ali Reza; Tavakkoli-Golpayegani, Ali; Haghani, Masoud; Mortazavi, Seyed Mohammad Javad

2014-01-01

138

Mobile satellite communications in the 1990's  

NASA Astrophysics Data System (ADS)

The evolution of Inmarsat global services from a single market and single service of the 1980's to all of the key mobile markets and a wide range of new terminals and services in the 1990's is described. An overview of existing mobile satellite services, as well as new services under implementation for introduction in the near and longer term, including a handheld satellite phone (Inmarsat-P), is provided. The initiative taken by Inmarsat in the integration of its global mobile satellite services with global navigation capability derived from GPS (Global Positioning System) and the GLONASS (Russian GPS) navigation satellite systems and the provision of an international civil overlay for GPS/GLONASS integrity and augmentation is highlighted. To complete the overview of the development of mobile satellite services in the 1990's, the known national and regional mobile satellite system plans and the various recent proposals for both orbiting and geostationary satellite systems for proving handheld satellite phone and/or data messaging services are described.

Singh, Jai

1992-07-01

139

Siting of GSM Base Station Antenna and Its Health Consequences  

Microsoft Academic Search

In Nigeria 98% of Global System for Mobile (GSM) base stations (cell sites) are sited within 20 meters from residential, offices, schools, business buildings, petrol stations and public arenas. 97.1% of these mobile base station antennas have their far field zone, which ranges between 110 m to 270 m, and are centred on densely populated areas. Cell phone antennas emit

R. E. Okonigene

2010-01-01

140

Design of a mobile coastal communications buoy  

E-print Network

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 ...

Hendry-Brogan, Meghan

2004-01-01

141

'Travelling while sitting down': Mobile phones, mobility and the communication landscape in Inhambane, Mozambique  

Microsoft Academic Search

This article examines the ways in which young men in the city of Inhambane, southern Mozambique, harness communication to express and address experiences of constrained physical and social mobility. It starts with an analysis of a highly valued form of oral communication – bater papo – that youth, especially young men, engage in on a daily basis before turning to

Julie Soleil Archambault

2012-01-01

142

Potential markets for a satellite-based mobile communications system  

NASA Technical Reports Server (NTRS)

The objective of the study was to define the market needs for improved land mobile communications systems. Within the context of this objective, the following goals were set: (1) characterize the present mobile communications industry; (2) determine the market for an improved system for mobile communications; and (3) define the system requirements as seen from the potential customer's viewpoint. The scope of the study was defined by the following parameters: (1) markets were confined to U.S. and Canada; (2) range of operation generally exceeded 20 miles, but this was not restrictive; (3) the classes of potential users considered included all private sector users, and non-military public sector users; (4) the time span examined was 1975 to 1985; and (5) highly localized users were generally excluded - e.g., taxicabs, and local paging.

Jamieson, W. M.; Peet, C. S.; Bengston, R. J.

1976-01-01

143

Protocol design for mobile radio group communications over satellite  

Microsoft Academic Search

The protocol design for a mobile radio service supporting half-duplex push-to-talk voice communications over mobile satellite systems is presented. Two types of protocols are considered, namely, a demand assignment multiple access protocol to assign channels only to those user groups in active sessions of conversations and a signaling protocol to arbitrate contentions among members of the same user group within

Victor C. M. Leung

1992-01-01

144

Providing Seamless Communication in Mobile Wireless Networks  

E-print Network

-mail: fbbakshi,pkrishna,pradhan,vaidyag@cs.tamu.edu Phone: (409) 862-3411 Technical Report TR-96-015y May 1, 1996 degradation. The motivation be- hind this study is to nd a cost e ective solution for minimizing impact's cell. Each BS is responsible for forwarding data between the mobile user in it's cell, and the wired

Vaidya, Nitin

145

Control Freaks How Online and Mobile Communication  

E-print Network

Steam engines: pumping water out of mines (Thomas Newcomen and John Calley, 1712) Mainframe computers Manufacture of computers: toxic waste Manufacture of mobile phones: depletion of rare metals 4 #12 was awkward The university-based tech community engaged in much online joking and sarcasm Written language

Lansky, Joshua

146

The use of mobile satellite communication terminals  

NASA Astrophysics Data System (ADS)

The role of small portable terminals in military satellite systems is examined; the discussion embraces terminals with an antenna reflector diameter of seven meters or less. Emphasis is placed on the specification of MARMOSET (Marconi Mobile Satellite Earth Terminal). Also considered are ship-borne satellite terminals, the improved SCOT terminal, interoperability, reduced downlink power, and reliability and availability.

Law, P. A.

147

Land-mobile satellite communication system  

NASA Technical Reports Server (NTRS)

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.

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

1993-01-01

148

Study on potential effects of "902-MHz GSM-type Wireless Communication Signals" on DMBA-induced mammary tumours in Sprague-Dawley rats.  

PubMed

The aim of the study was to detect whether long-term exposure to "902-MHz GSM-type Wireless Communication Signals" ("radio-frequency (RF)-exposure") would affect 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumours in female Sprague-Dawley rats. Five hundred female rats were each given a single oral dose of 17 mg DMBA per kg body weight (bw) at an age of 46-48 days. Three groups of 100 animals each were RF-exposed (902 MHz; crest factor 8; pulse width=0.57 ms) from the next day onwards to normal whole-body averaged doses (expressed as specific absorption rate, SAR) of 0.4, 1.3 or 4.0 W/kg bw (low/mid/high-dose group) for 4h/d, 5d/week, during 6 months. A sham-exposed and a cage-control group remained without RF-exposure (<0.01 mW/kg). Animals were weekly weighed and palpated for mammary tumours; all mammary glands were examined histopathologically. There were several statistically significant differences between RF-exposed groups and the sham-exposed group, as follows: All RF-exposed groups had, at different times, significantly more palpable tissue masses. There were fewer animals with benign neoplasms, but more with malignant tumours in the high-dose group. In addition, there were more adenocarcinomas in the low-dose group, more malignant neoplasms in the low- and high-dose groups, more animals with adenocarcinomas in the high-dose group, and fewer animals with fibroadenomas in the low- and mid-dose groups. The cage-control group had, when compared with the sham-exposed group, statistically significantly more palpable tissue masses, more benign and also more malignant neoplasms. The cage-control group had in most aspects the highest incidence and malignancy of neoplasms among all groups. None of the above findings in RF-exposed animals produced a clear dose-response relation and the responses of the cage-control group were either similar to or stronger than those of any of the RF-exposed group. The significant differences between the sham-exposed animals and one or more RF-exposed groups may be interpreted as evidence of an effect of RF-exposure. In the context of the results of the cage-control group, in the light of controversial results reported in the literature, and given the fact that the DMBA-mammary tumour model is known to be prone to high variations in the results, it is the authors' opinion that the differences between the groups are rather incidental ones. PMID:17981079

Hruby, Robert; Neubauer, Georg; Kuster, Niels; Frauscher, Michael

2008-01-01

149

Mobile satellite service communications tests using a NASA satellite  

NASA Technical Reports Server (NTRS)

Emerging applications of commercial mobile satellite communications include satellite delivery of compact disc (CD) quality radio to car drivers who can select their favorite programming as they drive any distance; transmission of current air traffic data to aircraft; and handheld communication of data and images from any remote corner of the world. Experiments with the enabling technologies and tests and demonstrations of these concepts are being conducted before the first satellite is launched by utilizing an existing NASA spacecraft.

Chambers, Katherine H.; Koschmeder, Louis A.; Hollansworth, James E.; ONeill, Jack; Jones, Robert E.; Gibbons, Richard C.

1995-01-01

150

Mobility of a Disaster Recover Communication System  

Microsoft Academic Search

What is the best platform to build a Disaster Management Communication System (DMCS)? There is a need to investigate how to best use a DMCS. The two most important uses of a DMCS for any size disaster, is the need for information and getting relief to those that need it. The DMCS needs to collect information from the people affected

Edward Sobanski; Barbara Nicolai

2011-01-01

151

Integrating Communication, Computer Access, Environmental Control & Mobility.  

ERIC Educational Resources Information Center

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…

Romich, Barry A.; Vagnini, Carol B.

152

NEW INFORMATION COMMUNICATION TECHNOLOGIES AND GRASSROOTS MOBILIZATION  

Microsoft Academic Search

In much of the recent literature on contemporary social movements there is call for a re-conceptualization of the definition and understanding of political struggle given the impact of new emerging information communication technologies (ICTs), and the Internet in particular, on social movement organizing, contentious politics, and the electoral political process. This paper undertakes an analysis of MoveOn within a critical

Victoria Carty

2010-01-01

153

Communication protocol for monitoring a large number of remotely distributed hazardous material detection devices  

Microsoft Academic Search

Modern wireless communication technologies opened up new avenues of data collection from remotely distributed environmental sensors. Global Mobile Communications (GSM) and satellite telephone services currently cover almost all parts of the world. With this development, it became feasible to place and collect data from remote sensors at locations which were previously inaccessible due to distance or extremely restrictive conditions. Although

T. Ozkul; A. Al Homoud

2003-01-01

154

MOBILE MAPPING APPLICATIONS BASED ON THE CYPRUS PERMANENT GPS NETWORK  

Microsoft Academic Search

This study describes the design and the installation of a pilot permanent GPS network in Cyprus, and evaluates its operation in order to produce the substructure for mobile mapping applications and any other type of relevant applications. The Continuously Reference Stations transmit their data via radio modems or GSM network and also have the capability to communicate with the users

E. Stylianidis; S. Spatalas; C. Pikridas; P. Patias

155

An aggressive approach to failure restoration of PCS mobility databases  

Microsoft Academic Search

In Personal Communications Services (PCS) networks, subscribers' current locations are usually maintained using a two-level hierarchical strategy with two types of databases, specifically, VLRs and HLRs. Location records might be lost due to the malfunction of mobility databases. GSM uses aggressive restoration to restore the HLR data from the VLRs. However, previous work on aggressive restoration is based on periodic

Tsan-Pin Wang; Chien-Chao Tseng; Wen-Kuang Chou

1997-01-01

156

Satellite-aided mobile communications, experiments, applications and prospects  

NASA Technical Reports Server (NTRS)

NASA's ATS-series of satellites were used in a series of communications and position fixing experiments with automotive vehicles, ships and aircraft. Applications of the communications were demonstrated and evaluated for public services including law enforcement, search and rescue, and medical emergency, and for commercial uses in the land and maritime transportation industries. The technical success of the experiments and the demonstrated potential value of the communications prompted a study that concluded an operational satellite-aided system would be a valuable augmentation of planned trunking or cellular type terrestrial mobile radio telephone systems.

Anderson, R. E.; Frey, R. L.; Lewis, J. R.; Milton, R. T.

1980-01-01

157

Payload system tradeoffs for mobile communications satellites  

NASA Technical Reports Server (NTRS)

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.

Moody, H. J.

1990-01-01

158

MSAT aeronautical mobile satellite communications terminal development  

NASA Technical Reports Server (NTRS)

CAL has undertaken the development of a new aeronautical mobile terminal for the North American MSAT market. The terminal is to meet the MSAT standard and is aimed in particular at the 300,000 general aviation and business aircraft in North America. The terminals are therefore relatively low cost and small in size when compared to those currently being produced for larger airline aircraft. The terminal incorporates a top mounted mechanical steered antenna and a unique antenna steering subsystem. An overview of the terminal design is presented.

Sutherland, C. A.; Sydor, J. T.

1995-01-01

159

Mobiware: QoS-aware middleware for mobile multimedia communications  

Microsoft Academic Search

Next generation wireless communications system will be required to support the seamless delivery of voice, video and data with hig h quality. Delivering hard Quality of Service (QOS) guarantees in the wireless domain is complex due t o large-scale mobility requirements, limited radio resources and fluctuati ng network conditions. To address this challenge we are developing a QOS-aware middleware platform

Andrew T. Campbell

1997-01-01

160

A Model and Measure of Mobile Communication Competence  

ERIC Educational Resources Information Center

This article deals with two studies that develop a measure and model of mobile communication competence (MCC). The first study examines the dimensionality of the measure by conducting an exploratory factor analysis on 350 students at a large university in the midwestern United States. Results identified six constructs across 24 items: willingness…

Bakke, Emil

2010-01-01

161

Secure Mobile and Wireless Communication Services for Collaborative Virtual Gaming  

Microsoft Academic Search

The paper reports on the current research activities and innovations provisioning secure ICT services. The identified research challenges and roadmap represent a significant step towards the development of global federated security services for the Web, Grid and particularly for future Mobile and Wireless communication (ICT platforms). The overall aim of the research is to provide seamless traversal to access distributed

Babak Akhgar; W. Orth; N. Meyer; M. Tuisku; G. Pipan; M. L. Gallego; J. A. Garcia; M. Cecchi; J.-N. Colin

2006-01-01

162

Scheduling and Control of Mobile Communications Networks with Randomly Time  

E-print Network

02912 USA hjk@dam.brown.edu Abstract-- Consider a communications network consisting of mobiles, some are weakened, and the distributions of the in- put file lengths can be heavy tailed. The resulting controls with randomly varying links, routing in ad-hoc networks, perturbed stochastic Liapunov functions, heavy tailed

163

Spread spectrum mobile communication experiment using ETS-V satellite  

NASA Technical Reports Server (NTRS)

The spread spectrum technique is attractive for application to mobile satellite communications, because of its random access capability, immunity to inter-system interference, and robustness to overloading. A novel direct sequence spread spectrum communication equipment is developed for land mobile satellite applications. The equipment is developed based on a matched filter technique to improve the initial acquisition performance. The data rate is 2.4 kilobits per sec. and the PN clock rate is 2.4552 mega-Hz. This equipment also has a function of measuring the multipath delay profile of land mobile satellite channel, making use of a correlation property of a PN code. This paper gives an outline of the equipment and the field test results with ETS-V satellite.

Ikegami, Tetsushi; Suzuki, Ryutaro; Kadowaki, Naoto; Taira, Shinichi; Sato, Nobuyasu

1990-01-01

164

Coherent versus noncoherent signaling for satellite-aided mobile communications  

NASA Technical Reports Server (NTRS)

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.

Davarian, F.; Sumida, J.

1986-01-01

165

Communication Systems Chair of Communication Systems  

E-print Network

1 | 36 Communication Systems 24th lecture Chair of Communication Systems Department of Applied Sciences University of Freiburg 2009 #12;2 | 36 Communication Systems last to final lecture Extension;3 | 36 Communication Systems GSM interfaces and components #12;4 | 36 Communication Systems GSM

Schindelhauer, Christian

166

Circadian pattern and burstiness in mobile phone communication  

NASA Astrophysics Data System (ADS)

The temporal communication patterns of human individuals are known to be inhomogeneous or bursty, which is reflected as heavy tail behavior in the inter-event time distribution. As the cause of such a bursty behavior two main mechanisms have been suggested: (i) inhomogeneities due to the circadian and weekly activity patterns and (ii) inhomogeneities rooted in human task execution behavior. In this paper, we investigate the role of these mechanisms by developing and then applying systematic de-seasoning methods to remove the circadian and weekly patterns from the time series of mobile phone communication events of individuals. We find that the heavy tails in the inter-event time distributions remain robust with respect to this procedure, which clearly indicates that the human task execution-based mechanism is a possible cause of the remaining burstiness in temporal mobile phone communication patterns.

Jo, Hang-Hyun; Karsai, Márton; Kertész, János; Kaski, Kimmo

2012-01-01

167

77 FR 40083 - Certain Personal Data and Mobile Communications Devices and Related Software; Institution of a...  

Federal Register 2010, 2011, 2012, 2013

...Mobile Communications Devices and Related Software; Institution of a Formal Enforcement...Apple Inc., and its subsidiary NeXT Software, Inc., both of Cupertino, California...mobile communications devices and related software. 75 FR 17434 (Apr. 6, 2010)....

2012-07-06

168

78 FR 34132 - Certain Portable Electronic Communications Devices, Including Mobile Phones and Components...  

Federal Register 2010, 2011, 2012, 2013

...Portable Electronic Communications Devices, Including Mobile Phones and Components Thereof; Correction to Notice of Receipt...Portable Electronic Communications Devices, Including Mobile Phones and Components Thereof, DN 2958; the Commission...

2013-06-06

169

Channel simulation to facilitate mobile-satellite communications research  

NASA Technical Reports Server (NTRS)

The mobile-satellite-service channel simulator, which is a facility for an end-to-end hardware simulation of mobile satellite communications links is discussed. Propagation effects, Doppler, interference, band limiting, satellite nonlinearity, and thermal noise have been incorporated into the simulator. The propagation environment in which the simulator needs to operate and the architecture of the simulator are described. The simulator is composed of: a mobile/fixed transmitter, interference transmitters, a propagation path simulator, a spacecraft, and a fixed/mobile receiver. Data from application experiments conducted with the channel simulator are presented; the noise converison technique to evaluate interference effects, the error floor phenomenon of digital multipath fading links, and the fade margin associated with a noncoherent receiver are examined. Diagrams of the simulator are provided.

Davarian, Faramaz

1987-01-01

170

The Globalstar mobile satellite system for worldwide personal communications  

NASA Technical Reports Server (NTRS)

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.

Wiedeman, Robert A.; Viterbi, Andrew J.

1993-01-01

171

Cockpit weather graphics using mobile satellite communications  

NASA Astrophysics Data System (ADS)

Many new companies are pushing state-of-the-art technology to bring a revolution in the cockpits of General Aviation (GA) aircraft. The vision, according to Dr. Bruce Holmes - the Assistant Director for Aeronautics at National Aeronautics and Space Administration's (NASA) Langley Research Center, is to provide such an advanced flight control system that the motor and cognitive skills you use to drive a car would be very similar to the ones you would use to fly an airplane. We at ViGYAN, Inc., are currently developing a system called the Pilot Weather Advisor (PWxA), which would be a part of such an advanced technology flight management system. The PWxA provides graphical depictions of weather information in the cockpit of aircraft in near real-time, through the use of broadcast satellite communications. The purpose of this system is to improve the safety and utility of GA aircraft operations. Considerable effort is being extended for research in the design of graphical weather systems, notably the works of Scanlon and Dash. The concept of providing pilots with graphical depictions of weather conditions, overlaid on geographical and navigational maps, is extremely powerful.

Seth, Shashi

172

Why is CDMA the solution for mobile satellite communication  

NASA Technical Reports Server (NTRS)

It is demonstrated that spread spectrum Code Division Multiple Access (CDMA) systems provide an economically superior solution to satellite mobile communications by increasing the system maximum capacity with respect to single channel per carrier Frequency Division Multiple Access (FDMA) systems. Following the comparative analysis of CDMA and FDMA systems, the design of a model that was developed to test the feasibility of the approach and the performance of a spread spectrum system in a mobile environment. Results of extensive computer simulations as well as laboratory and field tests results are presented.

Gilhousen, Klein S.; Jacobs, Irwin M.; Padovani, Roberto; Weaver, Lindsay A.

1989-01-01

173

Monitoring Heart Disease and Diabetes with Mobile Internet Communications  

PubMed Central

A telemedicine system is described for monitoring vital signs and general health indicators of patients with cardiac and diabetic conditions. Telemetry from wireless sensors and readings from other instruments are combined into a comprehensive set of measured patient parameters. Using a combination of mobile device applications and web browser, the data can be stored, accessed, and displayed using mobile internet communications to the central server. As an extra layer of security in the data transmission, information embedded in the data is used in its verification. The paper highlights features that could be enhanced from previous systems by using alternative components or methods. PMID:23213330

Mulvaney, David; Woodward, Bryan; Datta, Sekharjit; Harvey, Paul; Vyas, Anoop; Thakker, Bhaskar; Farooq, Omar; Istepanian, Robert

2012-01-01

174

Close relationships: A study of mobile communication records  

E-print Network

Mobile phone communication as a digital service generates ever-increasing datasets of human communication actions, which in turn allow us to investigate the structure and evolution of social interactions and their networks. These datasets can be used to study the structuring of such ego-centric networks with respect to the strength of the relationships by assuming monotonic dependence of the communication intensity on the strength of the social tie. Recently we have discovered that there are significant differences between the first and further 'best friends" from the point of view of age and gender preferences. Here we introduce a control parameter, namely the minimum ratio $r_{min}$ between the intensities of communication of the first and second "best friend" and use it to filter the data. We find that when $r_{min}$ is increased the identification of the "best friend" becomes less ambiguous and the earlier observed effects get stronger, thus corroborating them.

Palchykov, Vasyl; Dunbar, Robin I M; Kaski, Kimmo

2012-01-01

175

Close Relationships: A Study of Mobile Communication Records  

NASA Astrophysics Data System (ADS)

Mobile phone communication as digital service generates ever-increasing datasets of human communication actions, which in turn allow us to investigate the structure and evolution of social interactions and their networks. These datasets can be used to study the structuring of such egocentric networks with respect to the strength of the relationships by assuming direct dependence of the communication intensity on the strength of the social tie. Recently we have discovered that there are significant differences between the first and further "best friends" from the point of view of age and gender preferences. Here we introduce a control parameter p max based on the statistics of communication with the first and second "best friend" and use it to filter the data. We find that when p max is decreased the identification of the "best friend" becomes less ambiguous and the earlier observed effects get stronger, thus corroborating them.

Palchykov, Vasyl; Kertész, János; Dunbar, Robin; Kaski, Kimmo

2013-05-01

176

FEC decoder design optimization for mobile satellite communications  

NASA Technical Reports Server (NTRS)

A new telecommunications service for location determination via satellite is being proposed for the continental USA and Europe, which provides users with the capability to find the location of, and communicate from, a moving vehicle to a central hub and vice versa. This communications system is expected to operate in an extremely noisy channel in the presence of fading. In order to achieve high levels of data integrity, it is essential to employ forward error correcting (FEC) encoding and decoding techniques in such mobile satellite systems. A constraint length k = 7 FEC decoder has been implemented in a single chip for such systems. The single chip implementation of the maximum likelihood decoder helps to minimize the cost, size, and power consumption, and improves the bit error rate (BER) performance of the mobile earth terminal (MET).

Roy, Ashim; Lewi, Leng

1990-01-01

177

Adaptive channel estimation and equalization for rapidly mobile communication channels  

Microsoft Academic Search

This paper presents a reduced-complexity maximum-likelihood sequence estimation receiver, based on the Viterbi algorithm (VA), suitable for rapidly fading mobile communication channels. The channel impulse response is expanded onto a set of basis sequences and time-invariant (TI) expansion parameters. The proposed receiver continuously estimates the TI expansion parameters directly within the metric calculation of the VA. At every time instant

Ahmed El-sayed El-mahdy

2004-01-01

178

History of Antenna Technology for Mobile Communications in Korea  

NASA Astrophysics Data System (ADS)

In this paper, we discuss the development of wireless and mobile communications in Korea, current technological trends, and the future outlook on technological developments. Since the introduction of the telegraph and the telephone in September 1885, Korea's wired and wireless communications industry has consistently developed for over 100 years. Since 1984, upon the provision of the mobile telecommunications service, the industry has seen drastic qualitative and quantitative growth in terms of both technical and economic aspects, which played a crucial role in the rapid growth of the digital industry in Korea. After the era of the analog cellular service based on the Advanced Mobile Phone System (AMPS), a precursor to the modern mobile service, Korea became the world's first country to commercialize Code Division Multiple Access (CDMA) in 1996 and succeeded in commercializing CDMA 2000 lx (IMT 2000) in 2001. With further developments in the mobile communication technology, the technology for antennas also saw drastic advancements. As the mobile antennas moved from the second to the third generation, they grew from external models to very small internal models. At the same time, they evolved into highly functional and high performance multiple band and wide band antennas. Furthermore, Korea was the first country to commercialize and offer the Wireless Broadband Internet (WiBro) service in 2006. By leading the wireless communications standardization and exerting remarkable efforts in research and development, Korea is consolidating its status as an Information Technology (IT) leader in the global market. The antenna's inherent importance will be further emphasized in the near future as it satisfies the performance and structural needs of portable terminals necessary for realizing the projected establishment of the ubiquitous world. It is thought that antenna technologies will not be limited to simple concepts as previously experienced but will utilize various kinds of materials that build the terminals' structure and framework. Moreover, studies will be performed with an emphasis on multiple band, multiple directivity, and ultra-wide band. Accordingly, antenna technologies to which new concepts are applied, such as SMART antenna and MIMO antenna technologies and meta-materials, will surely be effective alternatives.

Min, Kyeong-Sik; Park, Chul-Keun; Kang, Suk-Youb

179

Aeronautical Mobile Airport Communications System (AeroMACS)  

NASA Technical Reports Server (NTRS)

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.

Budinger, James M.; Hall, Edward

2011-01-01

180

Influence of Mobile Phones on the Quality of ECG Signal Acquired by Medical Devices  

NASA Astrophysics Data System (ADS)

Health aspects of the use of radiating devices, like mobile phones, are still a public concern. Stand-alone electrocardiographic systems and those built-in, more sophisticated, medical devices have become a standard tool used in everyday medical practice. GSM mobile phones might be a potential source of electromagnetic interference (EMI) which may affect reliability of medical appliances. Risk of such event is particularly high in places remote from GSM base stations in which the signal received by GSM mobile phone is weak. In such locations an increase in power of transmitted radio signal is necessary to enhance quality of the communication. In consequence, the risk of interference of electronic devices increases because of the high level of EMI. In the present paper the spatial, temporal, and spectral characteristics of the interference have been examined. The influence of GSM mobile phone on multilead ECG recordings was studied. It was observed that the electrocardiographic system was vulnerable to the interference generated by the GSM mobile phone working with maximum transmit power and in DTX mode when the device was placed in a distance shorter than 7.5 cm from the ECG electrode located on the surface of the chest. Negligible EMI was encountered at any longer distance.

Buczkowski, T.; Janusek, D.; Zavala-Fernandez, H.; Skrok, M.; Kania, M.; Liebert, A.

2013-10-01

181

Land mobile communications satellite missions (LAMOCOSAMIS) task 2: Functional requirements  

NASA Astrophysics Data System (ADS)

Existing, planned, and foreseeable land mobile communication services in Europe were reviewed. Functional characteristics of available and new services were studied. Assumptions on global architecture were made. Regulatory aspects were investigated. The system should offer two-way telephony with the same quality as for the wire network; continous coverage, except in the low population density area, and including coverage of the coastal area; at least 10 Erlangs/sq km, allowing for a 25 mE per subscriber to serve 400 subscribers/sq km; possibility to call a mobile subscriber without knowing its geographical position, switched-on mobile terminal being permanently located by the system (roaming); automatic switchover of calls without break when a mobile moves from one cell to another (handover); service to users of public transport; possibility to use portable or pocket mobile terminal; and data transmission either by using a modem on the actual analog systems, or directly on the future digital systems, allowing message transmission or facsimile, connection of computer or terminals, with the possibility of integration in the future Integrated Service Digital Network.

1985-12-01

182

Breaking GSM with rainbow Tables  

E-print Network

Since 1998 the GSM security has been academically broken but no real attack has ever been done until in 2008 when two engineers of Pico Computing (FPGA manufacture) revealed that they could break the GSM encryption in 30 seconds with 200'000$ hardware and precomputed rainbow tables. Since then the hardware was either available for rich people only or was confiscated by government agencies. So Chris Paget and Karsten Nohl decided to react and do the same thing but in a distributed open source form (on torrent). This way everybody could "enjoy" breaking GSM security and operators will be forced to upgrade the GSM protocol that is being used by more than 4 billion users and that is more than 20 years old.

Meyer, Steven

2011-01-01

183

Challenges in the migration to 4G mobile systems  

Microsoft Academic Search

With the rapid development of wireless communication networks, it is expected that fourth-generation mobile systems will be launched within decades. 4G mobile systems focus on seamlessly integrating the existing wireless technologies including GSM, wireless LAN, and Bluetooth. This contrasts with 3G, which merely focuses on developing new standards and hardware. 4G systems supports comprehensive and personalized services, providing stable system

Suk Yu Hui; Kai Hau Yeung

2003-01-01

184

Interference Analysis for an Aeronautical Mobile Airport Communications System  

NASA Technical Reports Server (NTRS)

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

Wilson, Jeffrey D.; Kercewski, Robert J.

2010-01-01

185

Interference Analysis for an Aeronautical Mobile Airport Communications System  

NASA Technical Reports Server (NTRS)

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.

Wilson, Jeffrey D.; Kerczewski, Robert J.

2011-01-01

186

PERCEPTIONS OF SECURITY AND PRIVACY WHEN USING MOBILE COMMUNICATION SYSTEMS An Analysis of Administrative and Line Staff Congruence  

Microsoft Academic Search

Mobile communication systems have revolutionized business communication and become common communication tools within business organizations. The dramatic increase in the use of mobile communication systems would not have been possible without the assumption of information security and privacy. However, in many workplaces, this assumption is wrong, and, in fact, mobile communications are vulnerable in many ways. The purpose of this

Cheon-Pyo Lee; Xin Luo; Merrill Warkentin

187

Energy and environmental aspects of mobile communication systems  

E-print Network

The reduction of the energy consumptions of a Telecommunication Power System represents one of the critical factors of the telecommunication technologies, both to allow a sizeable saving of economic resources and to realize "sustainable" development actions. The consumption of about one hundred base stations for mobile phones were monitored for a total of over one thousand days, in order to study the energy consumption in relation to the environmental, electric and logistics parameters of the stations themselves. It was possible to survey, then, the role of the mobile communication systems in the general national energy framework and to plot the best areas of intervention for saving energy and improving the environmental impact, showing the role played by air conditioning and transmission equipments. Finally, new transmission algorithms and the use of renewable energy based techniques have been tested.

Lubritto, C; Vetromile, C; Curcuruto, S; Logorelli, M; Marsico, G; D'Onofrio, A; 10.1016/j.energy.2010.11.039

2011-01-01

188

More About Lens Antenna For Mobile/Satellite Communication  

NASA Technical Reports Server (NTRS)

Report presents additional details of design of proposed phased-array antenna described in "Lens Antenna for Mobile/Satellite Communication" (NPO-16948). Intended to be compact and to lie flat on top of vehicle on ground. Transmits and receives circularly polarized radiation in frequency ranges of 821 to 825 MHz and 860 to 870 MHz. Transmitting and receiving beams electronically steerable to any of 48 evenly spaced directions to provide complete azimuth coverage, and would be fixed, but wide, in elevation, to provide coverage at elevation angles from 20 degrees to 60 degrees.

Rahmat-Samii, Y.; Bodnar, D. G.; Rainer, B. K.

1990-01-01

189

Koubachi: A Mobile Phone Widget to Enable Affective Communication with Indoor Plants  

E-print Network

Koubachi: A Mobile Phone Widget to Enable Affective Communication with Indoor Plants Philipp of the plant. The user can access this data at all times through a small mobile phone application, a so called mobile widget. In case the node detects a change in the health status, the mobile widget is brought

190

Design for Social Presence and Exploring Its Mediating Effect in Mobile Data Communication Services  

ERIC Educational Resources Information Center

The mobility, flexibility, convenience, and ubiquity of mobile data services (MDS) have contributed to their enormous growth and popularity with users. MDS allow users to communicate through mobile texting (mTexting), mobile Instant Messaging (mIM), multimedia messaging services (MMS), and email. A unique feature of MDS that enhances its…

Ogara, Solomon Omondi

2011-01-01

191

A Novel "Green" Inkjet-Printed Monopole Antenna Topology for Concurrent RFID and Cellular Communications  

E-print Network

of RFID and cell phones is inevitability and future developments following this trend are expected Communications (GSM) adopted primary in Europe and Asia. The cell phones within a few years are expected phones will have a tremendous impact on the business proposition of mobile telephony enabling the users

Tentzeris, Manos

192

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

Microsoft Academic Search

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

Mikko V. J. Heikkinen; Sakari Luukkainen

2010-01-01

193

Robust Timing Synchronization in Aeronautical Mobile Communication Systems  

NASA Technical Reports Server (NTRS)

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.

Xiong, Fu-Qin; Pinchak, Stanley

2004-01-01

194

Multi-purpose HealthCare Telemedicine Systems with mobile communication link support  

PubMed Central

The provision of effective emergency telemedicine and home monitoring solutions are the major fields of interest discussed in this study. Ambulances, Rural Health Centers (RHC) or other remote health location such as Ships navigating in wide seas are common examples of possible emergency sites, while critical care telemetry and telemedicine home follow-ups are important issues of telemonitoring. In order to support the above different growing application fields we created a combined real-time and store and forward facility that consists of a base unit and a telemedicine (mobile) unit. This integrated system: can be used when handling emergency cases in ambulances, RHC or ships by using a mobile telemedicine unit at the emergency site and a base unit at the hospital-expert's site, enhances intensive health care provision by giving a mobile base unit to the ICU doctor while the telemedicine unit remains at the ICU patient site and enables home telemonitoring, by installing the telemedicine unit at the patient's home while the base unit remains at the physician's office or hospital. The system allows the transmission of vital biosignals (3–12 lead ECG, SPO2, NIBP, IBP, Temp) and still images of the patient. The transmission is performed through GSM mobile telecommunication network, through satellite links (where GSM is not available) or through Plain Old Telephony Systems (POTS) where available. Using this device a specialist doctor can telematically "move" to the patient's site and instruct unspecialized personnel when handling an emergency or telemonitoring case. Due to the need of storing and archiving of all data interchanged during the telemedicine sessions, we have equipped the consultation site with a multimedia database able to store and manage the data collected by the system. The performance of the system has been technically tested over several telecommunication means; in addition the system has been clinically validated in three different countries using a standardized medical protocol. PMID:12694629

Kyriacou, E; Pavlopoulos, S; Berler, A; Neophytou, M; Bourka, A; Georgoulas, A; Anagnostaki, A; Karayiannis, D; Schizas, C; Pattichis, C; Andreou, A; Koutsouris, D

2003-01-01

195

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

NASA Technical Reports Server (NTRS)

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.

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

1993-01-01

196

Considerations of digital phase modulation for narrowband satellite mobile communication  

NASA Technical Reports Server (NTRS)

The Inmarsat-M system for mobile satellite communication is specified as a frequency division multiple access (FDMA) system, applying Offset Quadrature Phase Shift Keying (QPSK) for transmitting 8 kbit/sec in 10 kHz user channel bandwidth. We consider Digital Phase Modulation (DPM) as an alternative modulation format for INMARSAT-M. DPM is similar to Continuous Phase Modulation (CPM) except that DPM has a finite memory in the premodular filter with a continuous varying modulation index. It is shown that DPM with 64 states in the VA obtains a lower bit error rate (BER). Results for a 5 kHz system, with the same 8 kbit/sec transmitted bitstream, is also presented.

Grythe, Knut

1990-01-01

197

Speech coding at 4800 bps for mobile satellite communications  

NASA Technical Reports Server (NTRS)

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.

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

1988-01-01

198

Isolated and coupled superquadric loop antennas for mobile communications applications  

NASA Technical Reports Server (NTRS)

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.

Jensen, Michael A.; Rahmat-Samii, Yahya

1993-01-01

199

Speech coding at 4800 bps for mobile satellite communications  

NASA Astrophysics Data System (ADS)

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.

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

1988-05-01

200

A study and experiment plan for digital mobile communication via satellite  

Microsoft Academic Search

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

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

1978-01-01

201

Assessing mobile phone communication utility preferences in a social support network  

Microsoft Academic Search

While it is generally accepted that the mobile cell phone has become ubiquitous within society for communicating, the actual use of the utilities on a phone have not been reported. Understanding how communication patterns are changing in society as a result of the mobile cell phone will enable the development and\\/or modification of existing cell phone utilities, the concept of

Elizabeth M. LaRue; Ann M. Mitchell; Lauren Terhorst; Hassan A. Karimi

2010-01-01

202

Satellite constellations summary, analysis and design for China mobile satellite communication  

Microsoft Academic Search

We proposed and studied a number of methods of satellite constellation design for regional mobile satellite communication (MSC), and obtained some useful results for China's regional MSC. These methods of constellation design can also be applied for other regional mobile satellite communication systems

Duan Shaohua; Zhang Zhongzhao; Zhang Naitong

1998-01-01

203

Hybrid beam steering system for laser communication between mobile platforms  

NASA Astrophysics Data System (ADS)

For many practical needs, laser communication systems must support operation between mobile platforms. Engineering robust links; however, will depend on several innovations. In particular, successful pointing, acquisition, and tracking (PAT) require the use of a beacon signal and the capability of accurate and agile alignment of the line-of-sight (LOS) between the communicating terminals performed over a large field of regard. While mechanical devices, such as gimbals, offer relatively slow tracking over a very wide range, they lack in pointing bandwidth necessary for rejecting high frequency vibrations and beam deflection caused by the optical turbulence. In contrast, fast steering and especially non-mechanical devices, such as Bragg cells, enjoy very high bandwidth (on the order of several kHz), but their effective range is very small. Inherent limitations of both gimbals and fast steerers result in shortcomings of the entire PAT system when either of these devices is used as a sole beam steerer. Therefore, focus needs to be shifted to hybrid architectures, exploiting the advantages of the constituting elements. This paper demonstrates a system combining a robotic manipulator with two acousto-optic cells and presents the algorithm development and the simulation results.

Nikulin, Vladimir V.; Nicholson, Donald J.

2007-02-01

204

Mobile Phones as Tool to Increase Communication and Location Awareness of Users  

E-print Network

Mobile Phones as Tool to Increase Communication and Location Awareness of Users Albrecht Schmidt.Atterer}@ifi.lmu.de ABSTRACT Mobile phones have become a ubiquitous technology and for many people a daily companion. The prime capabilities of mobile phones that can support the creation of persuasive technologies. The focus of the work

205

EMERGING PATTERNS OF AMERICAN MOBILE PHONE USE: Electronically-mediated communication in transition  

E-print Network

EMERGING PATTERNS OF AMERICAN MOBILE PHONE USE: Electronically-mediated communication in transition campuses regarding their use of mobile phones for both talking and texting. The results suggest that the mobile phone platform is still a medium in transition but that some usage patterns may be gender

Carlini, David

206

Low and Medium-Gain antennas for Mobile Satellite Communications (MSC) and Navigation  

Microsoft Academic Search

In this paper are introduced Low-Gain Omnidirectional Antennas for Mobile Satellite Communications (MSC) and Navigation. In many respects the Mobile Satellite Antenna (MSA) infrastructures currently available for MSC and Navigation. Medium and high gain MSA need to track the satellite, following both movements of mobiles and satellite orbital motions. Sometimes this is difficult and expensive to synchronize and have to

Stojce Dimov Ilcev

2011-01-01

207

How can we use mobile apps for disaster communications in Taiwan: Problems and possible practice  

Microsoft Academic Search

The growth rate of global smart phone in 2010 is as high as 78.1%, showing that smart phone gradually becomes the mainstream in the mobile phone market. Smart phone has the function of installing applications, provides users with more diversified mobile value-added services and will change users' communication habits in the future. Mobile communication follows the development trend of 3G

Sz Jie Sung

2011-01-01

208

An overview of the OmniTRACS: The first operational mobile Ku-band satellite communications  

NASA Technical Reports Server (NTRS)

The service features of the OmniTRACS system developed by Omninet Communications Services of Los Angeles, California are described. This system is the first operational mobile Ku-band satellite communications system that provides two-way messaging and position determination and reporting services to mobile users on a nationwide basis. The system uses existing Ku-band satellites under a secondary international allocation for mobile satellite services.

Salmasi, Allen

1988-01-01

209

Investigation of the performance of EOTD for GSM users in telematics applications  

NASA Astrophysics Data System (ADS)

Location-based services have been standardized for incorporation into 3rd generation wireless communications as a result of the Federal Communications Commission"s (FCC) mandate on wireless carriers to provide automatic location information (ALI) during emergency911 calls. This mandate has driven the wireless carriers to explore terrestrial, satellite, and hybrid based location technology solutions. This paper presents a communications model that investigates the position accuracyof a Global Standard Mobile (GSM) phone employing the enhanced observed time difference (EOTD) location technology. The EOTD positioning technique requires the mobile station (MS) to detect signals from at least three base stations (BS). This studyassumes the three BSs are synchronized in time. For a given BS geometry with respect to the MS, a Monte Carlo simulation was performed to assess the two-dimensional position accuracyof the MS in Rayleigh and Ricean fading channels. In each channel, a Monte Carlo simulation was performed for a good and a bad BS-to-MS geometry. The paper concludes with a list of pros/cons of implementing EOTD as a location technologyenabler in telematics applications.

Sharawi, Mohammad S.; Aloi, Daniel N.

2003-08-01

210

A self-verification authentication mechanism for mobile satellite communication systems  

Microsoft Academic Search

In order to provide an opportunity to make personal communication as broad as possible, mobile satellite communication systems have recently drawn much attention. However, any communication system raises two major challenging issues: (1) how to determine whether actors are whom they claim to be; and (2) how to protect data against unauthorized disclosure. Although the secret-key cryptosystem (SKC) and the

Tzung-Her Chen; Wei-Bin Lee; Hsing-Bai Chen

2009-01-01

211

Study on Communication between Home and School System Based on Mobile Education Platform  

Microsoft Academic Search

As the two significant sides of the education, it is all-important to communicate and intercourse between the home and school. With the development of the information and the internet, Notebook computers, mobile phones and other modern communications equipments continues to increase, they are constructing the timely exchange of information and the emotion platform. So this article firstly introduces the communication

Weifeng Jiao; Jialing Zhao

2007-01-01

212

A Robust and Affordable Mobile Communications System for Emergency Management and Crisis Response  

E-print Network

A Robust and Affordable Mobile Communications System for Emergency Management and Crisis Response Vegas, Nevada, USA. The Need for "First Responder" Integrated Emergency Communications In today's hyper, emergency managers, and relief workers may struggle to communicate during a crisis. Further, we do not all

Bowman, Michael

213

Int. J. Emergency Management, Vol. 4, No. 4, 2007 649 Robust and affordable mobile communications for  

E-print Network

Int. J. Emergency Management, Vol. 4, No. 4, 2007 649 Robust and affordable mobile communications.gantt@murraystate.edu Abstract: During any emergency reliable communications can be a matter of life-and-death. First-responder communications are widely seen as a critical emergency management issue identified by Hurricane Katrina

Bowman, Michael

214

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

E-print Network

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

Mostofi, Yasamin

215

Using satellite communications for a mobile computer network  

NASA Technical Reports Server (NTRS)

The topics discussed include the following: patrol car automation, mobile computer network, network requirements, network design overview, MCN mobile network software, MCN hub operation, mobile satellite software, hub satellite software, the benefits of patrol car automation, the benefits of satellite mobile computing, and national law enforcement satellite.

Wyman, Douglas J.

1993-01-01

216

David Florida Laboratory: Support for mobile satellite communications  

NASA Technical Reports Server (NTRS)

The comprehensive integration and environmental (including RF) test facilities of the Canadian Space Agency's David Florida Laboratory (CSA)(DFL) were used extensively for the MSAT Program. Following a description of the facilities, the paper outlines their application to the qualification of the two MSAT satellites following an overview of the test plan. Particular emphasis is given to passive intermodulation measurement (PIM) demands, which for the MSAT satellites, contributed to the need to extend the anechoic chamber. The extended chamber was also used for an EMC test and SAR signature test of the RADARSAT satellite. The DFL's facilities are being used for additional aspects of mobile satellite communications. One shielded anechoic Extra High Frequency (EHF) chamber and associated test equipment are employed predominantly for measuring the performance of the IRIDIUM satellites' Engineering Model Gateway Moveable Antennas (EM)(GMA). Other chambers are used for testing aeronautical antennas on behalf of Inmarsat. Still others combine thermal and PIM testing. The paper concludes with a review of the test requirements of evolving satcom missions such as Inmarsat Aero-1.

Dumoulin, Jean-Guy; Mamen, Rolf

1995-01-01

217

No mutagenic or recombinogenic effects of mobile phone fields at 900 MHz detected in the yeastSaccharomyces cerevisiae  

Microsoft Academic Search

Both actively growing and resting cells of the yeast Saccharomyces cerevisiae were exposed to 900-MHz fields that closely matched the Global System for Mobile Communication (GSM) pulsed modulation format signals for mobile phones at specific absorption rates (SAR) of 0.13 and 1.3 W\\/kg. Two identical anechoic test chambers were constructed to perform concurrent control and test experiments under well-controlled exposure

Pascal Gos; Bernhard Eicher; Wolf-Dietrich Heyer

2000-01-01

218

Communications and entertainment onboard a high-speed public transport system  

Microsoft Academic Search

This article discusses architectural design at the conceptual\\/functional level of communication and entertainment services onboard a high-speed public transport system, such as a high-speed train, a transoceanic cruise ship, or even a mid- to long-range airplane. Existing commercial mobile communication services, such as AMPS and GSM, are inaccessible to passengers onboard these public transport systems. A hierarchical architecture is laid

Kun-De Lin; Jin-Fu Chang

2002-01-01

219

GNSS data dissemination over mobile devices  

NASA Astrophysics Data System (ADS)

High-rate data availability is being considered the most limiting factor for real-time and near-real-time differential GNSS positioning applications where high-accruracy is principal. Combination of expanding Internet and GSM communications brings an innovative, lightweight and cost-effective technique comparing to radio transmissions and gives an alternative way for data streaming. Experiences with development of platform independent tools for mobile information devices (such as cellular phones and wireless-enabled PDAs) based on client-server architecture are presented. For design testing, utilization of Mobile Information Profile 2.0 (MIDP) operating over Connected, Limited Device Configuration 1.0 (CLDC ) is suggested.

Landspersky, D.; Hill, C.; Moore, T.

2003-04-01

220

Mobile ad hoc networks for oceanic aircraft communications  

E-print Network

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 ...

Kingsbury, Ryan W

2009-01-01

221

A Study on the Role of Mobile Phone Communication in Tuberculosis DOTS Treatment  

PubMed Central

Background: Every year, a lot of Tuberculosis (TB) patients undergo Directly Observed Treatment Short-course (DOTS) in Salem city, one of the high TB districts in South India. Mobile phone usage among these patients and health workers is common. Mobile phone communication has a great potential in TB treatment. Objectives: To analyze the mobile phone usage and its effectiveness in TB DOTS treatment. Materials and Methods: A cross-sectional survey with 150 TB patients was followed by a focus group discussion with treatment supervisors, DOTS providers, and health workers. Results: Majority of patients use mobile phones to make calls to health workers to clarify their doubts on side effects, food, and symptoms of the disease. TB treatment supervisors effectively use mobile phones to counsel patients to adhere to the treatment regimen. Patients see mobile phones as a useful communication tool in TB treatment though they prefer direct interpersonal communication with health workers. Though the mobile ownership is 68% among the TB patients, many of them are not able to send text messages or read messages in English. Conclusion: Mobile phone possession and usage is high among the patients. Patients need to be trained to use mobile phone features such as alarm, voice mail, and interactive voice response. Incentives like free talk time and short message service (SMS) will encourage patients to communicate frequently with health workers, thereby, increasing the chances of better adherence to DOTS. SMS could be made available in the regional languages. PMID:24302824

Elangovan, R; Arulchelvan, S

2013-01-01

222

Developing a Conceptual Unmanned Aerial Vehicle Communications Mobile AD Hoc Network Simulation Model.  

National Technical Information Service (NTIS)

A growing demand for increased networking interoperability has spawned a requirement for ad hoc networking. One proposal to satisfy the need is development of Unmanned Aerial Vehicle (UAV) communications Mobile Ad Hoc Networks (NANET) . In order to establ...

H. L. Blackshear

2002-01-01

223

Activity Analysis Enabling Real-Time Video Communication on Mobile Phones for Deaf Users  

E-print Network

breakdowns, but does not affect the users' perception of adopting the technol- ogy. These results show language video communication on off-the-shelf mobile phones between users that wear no special clothing

Anderson, Richard

224

76 FR 30154 - Maritime Communications/Land Mobile, LLC, Licensee of Various Authorizations in the Wireless...  

Federal Register 2010, 2011, 2012, 2013

...officer and a director of the company. See Maritime Communications/Land Mobile...having an interest in the company. Maritime did not disclose any involvement...characterized as his wife's company than Maritime led the Commission to...

2011-05-24

225

A unified approach tothe performance analysis of speed estimation techniques in mobile communication  

Microsoft Academic Search

Estimation of the mobile speed, or equivalently, the maximum Doppler frequency, is of importance in a variety of applications in wireless mobile communications. In this paper, a unified framework for the performance analysis of several major speed estimation techniques is presented, which allows a fair comparison between all the methods, analytically. Interestingly, it is proved that all these methods are

Ali Abdi; Hong Zhang; Cihan Tepedelenlioglu

2008-01-01

226

A Reliable Connection Migration Mechanism for Synchronous Transient Communication in Mobile Codes  

E-print Network

. A special form of migration is mobile agent that has as its defining trait the ability to travelA Reliable Connection Migration Mechanism for Synchronous Transient Communication in Mobile Codes during their migration. This mechanism supports concurrent migration of both endpoints of a connection

Xu, Cheng-Zhong

227

Research on Mobile English Assistant Learning System based on Wireless Communication  

Microsoft Academic Search

In order to improve learning flexibility and efficiency, and break the constraints of time and space, an English mobile learning system based on Bluetooth as proposed and realized in the paper. English mobile learning system used Bluetooth technology as the wireless communication media. To accommodate with the characteristic of portable devices, the system is designed for low power consumption and

Guoliang Zhang; Feng Xiong; Qi Luo

2007-01-01

228

WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2005; 5:825845  

E-print Network

National University of Education, San 7-1, Darakri, Chongwon- Gun, Chungbuk, 363-791, Korea Summary MobileWIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2005; 5:825­845 Published Science, University of Oklahoma, Norman, OK 73019-6151, U.S.A. 2 Department of Technology Education, Korea

Atiquzzaman, Mohammed

229

The design of a linear L-band high power amplifier for mobile communication satellites  

NASA Technical Reports Server (NTRS)

A linear L-band solid state high power amplifier designed for the space segment of the Mobile Satellite (MSAT) mobile communication system is described. The amplifier is capable of producing 35 watts of RF power with multitone signal at an efficiency of 25 percent and with intermodulation products better than 16 dB below carrier.

Whittaker, N.; Brassard, G.; Li, E.; Goux, P.

1990-01-01

230

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

ERIC Educational Resources Information Center

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…

Norris, Daniel T.

2007-01-01

231

Guidelines for the Use of Mobile Computing and Communications Devices in Classes at McGill  

E-print Network

as not disruptive1 3. Not allowed at all. , and; 1. Allowed under specified conditions Mobile computing and contribute to ensuring individual and collective good classroom experiences.); b. When "No technology time.g., guest speaker. 2. Allowed as long as not disruptive Mobile computing and communications devices

Barthelat, Francois

232

Improving the Communication of Spatial Information in Crisis Response by Combining Paper Maps and Mobile Devices  

Microsoft Academic Search

Ecient and eective communication between mobile units and the central emergency operation center is a key factor to respond successfully to the challenges of emergency management. Nowadays, the only ubiquitously available modality is a voice channel through mobile phones or radio transceivers. This makes it often very dicult to convey exact geographic locations and can lead to misconceptions with severe

Johannes Schoning; Michael Rohs; Antonio Kruger; Christoph Stasch

233

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

E-print Network

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

California at San Diego, University of

234

Phased Arrays of Ground and Airborne Mobile Terminals for Satellite Communications  

NASA Technical Reports Server (NTRS)

Phased array antenna is beginning to play an important in the arena of mobile/satellite communications. Two examples of mobile terminal phased arrays will be shown. Their technical background, challenges, and cost drivers will be discussed. A possible solution to combat some of the deficiencies of the conventional phased array by exploiting the phased reflectarray technology will be briefly presented.

Huang, John

1996-01-01

235

LOOPUS Mob-D: System concept for a public mobile satellite system providing integrated digital services for the Northern Hemisphere from an elliptical orbit  

NASA Technical Reports Server (NTRS)

A new concept for a satellite based public mobile communications system, LOOPUS Mob-D, is introduced, whereby most of the classical problems in mobile satellite systems are approached in a different way. The LOOPUS system will offer a total capacity of 6000 high rate channels in three service areas (Europe, Asia, and North America), covering the entire Northern Hemisphere with a set of group special mobile (GSM) compatible mobile services, eventually providing the 'office in the car'. Special characteristics of the LOOPUS orbit and the communications network architecture are highlighted.

Kuhlen, H.; Horn, P.

1990-01-01

236

From Windscreen to Widescreen: Screening Technologies and Mobile Communication  

Microsoft Academic Search

This article suggests that studies of mobile media need to be more attentive to the history of screening technologies. The development of screening technologies is examined by identifying six characteristics—storage and access, interactivity, mobility, control, informationalization, and convergence\\/translation—through the context of automobility. A brief history of the informationalization of driving, mobile entertainment in the car, and networked automobiles is used

Jeremy Packer; Kathleen F. Oswald

2010-01-01

237

Split-proxy concept for application layer handover in mobile communication systems  

Microsoft Academic Search

This paper presents an HTTP based approach for handover within and between heterogeneous communication systems. Therefore a Split-Proxy-Concept has been developed, consisting of client- and server side proxies. Communication between proxies takes place using TCP connections, thus benefiting from existing IP mobility approaches and virtual serial connections as provided by Bluetooth or circuit switched access. The latter allows to forgo

Jens Kammann; Tim Blachnitzky

2002-01-01

238

Link search algorithms for a spread-spectrum mobile communication network with directive\\/adaptive antennas  

Microsoft Academic Search

A non-centralized fully distributed mobile communication network with directive or adaptive antennas is proposed. Every node uses directive or adaptive antennas for transmitting and receiving communication signals. The spatial and temporal synchronization of the transmitting and receiving antenna beams is accomplished by employing the Global Positioning System (GPS) information and a double-ended spatial search algorithm. This research focuses on the

Tien-Yow Liu; Robert A. Scholtz

1998-01-01

239

Using mobile communication technology in high school education: Motivation, pressure, and learning performance  

Microsoft Academic Search

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 inter- action between the student and the instructor and improving learning efficiency. Social presence and information richness theory was applied to analyze the media and their impacts on the instruction process firstly.

Pei-luen Patrick Rau; Qin Gao; Li-mei Wu

2008-01-01

240

Proposition of a communication system used in mobility by users with physical disabilities, focus on  

E-print Network

on cerebral palsy with athetoid problems Yohan Guerrier, Christophe Kolski Univ Lille Nord de France, F-59000 system of communication for people with cerebral palsy (CP) with athetoid problems. These people have; mobility; Disabled user; Cerebral palsy (CP); Slurred speech; Communication support I. INTRODUCTION

Paris-Sud XI, Université de

241

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

Microsoft Academic Search

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

Takeo Ohgane; Takanori Shimura; Naoto Matsuzawa; Hideichi Sasaoka

1993-01-01

242

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

ERIC Educational Resources Information Center

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…

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

2008-01-01

243

Using mobile devices to support communication between emergency medical responders and deaf people  

Microsoft Academic Search

Fast and effective communication is crucial during medical emergencies, but patients' disabilities can make it a challenging task for emergency medical responders. This paper proposes a mobile system to deal with the communication barrier between medical responders and deaf patients. The system allows medical responders to quickly browse a collection of emergency-related sentences, and show videos of the corresponding translations

Fabio Buttussi; Luca Chittaro; Elio Carchietti; Marco Coppo

2010-01-01

244

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

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

245

Mobile Communications for Medical Care a study of current and future healthcare and health promotion applications, and  

E-print Network

Mobile Communications for Medical Care a study of current and future healthcare and health examines the use of mobile networks to enhance healthcare (so-called "mHealth"), as an example of how mobile communications can contribute to sustainable development. We define mHealth as "a service

Talbot, James P.

246

Communication protocols and on-board processor for a new national scale private mobile radio service [medical information environment  

Microsoft Academic Search

A satellite-aided mobile radio communication service opens a new horizon of the integrated medical information environment. Doctors of medicine working on fixed or mobile stations, located in remote geographical areas, are able to communicate\\/cooperate each other by exchanging, handling and processing medical data simultaneously. The authors present a new national scale private mobile radio service using satellite facilities. This new

S. Kotsopoulos; D. Lymberopoulos

1992-01-01

247

Effects of GSM-modulated 900?MHz radiofrequency electromagnetic fields on the hematopoietic potential of mouse bone marrow cells.  

PubMed

Studies describing the influence of radiofrequency electromagnetic fields on bone marrow cells (BMC) often lack functional data. We examined the effects of in vivo exposure to a Global System for Mobile Communications (GSM) modulated 900?MHz RF fields on BMC using two transplantation models. X-irradiated syngeneic mice were injected with BMC from either RF-field-exposed, sham-exposed or cage control mice. Twelve weeks after transplantation, no differences in thymocyte number, frequency of subpopulations and cell proliferation were found in mice receiving BMC from either group. Also, in the spleen cell number, percentages of B/T cells, B/T-cell proliferation, and interferon ? (IFN-?) production were similar in all groups. In parallel, a mixture of BMC from congenic sham- and RF-exposed mice were co-transplanted into lymphopenic Rag2 deficient mice. BMC from RF-exposed and sham-exposed mice displayed no advantage or disadvantage when competing for the replenishment of lymphatic organs with mature lymphocytes in Rag2 deficient mice. This model revealed that BMC from sham-exposed and RF-exposed mice were less efficient than BMC from cage control mice in repopulating the thymus, an effect likely due to restraint stress. In conclusion, our results showed no effects of in vivo exposure to GSM-modulated RF-fields on the ability of bone marrow (BM) precursors to long-term reconstitute peripheral T and B cell compartments. Bioelectromagnetics 35:559-567, 2014. © 2014 Wiley Periodicals, Inc. PMID:25256206

Rosado, Maria Manuela; Nasta, Francesca; Prisco, Maria Grazia; Lovisolo, Giorgio Alfonso; Marino, Carmela; Pioli, Claudio

2014-12-01

248

Preprocessing communication unit (PCU) with short message service (SMS) communication channels for AVL tracking  

NASA Astrophysics Data System (ADS)

The Preprocessing GPS - SMS Communication Unit (PCU) is a mobile tracking device used within AVL tracking systems for determining the location of vehicles. It was designed primarily to utilize the SMS service of the GSM network for communicating. The use of SMS messages is part of an effort aimed at providing a cost effective alternative for tracking the location of vehicles. Its primary function is to send information about user location across a GSM network to a Central Base Station (CBS) from which assets are being tracked. Though SMS is the main bearer, the unit is also capable of using Circuit Switch Data Service (CSD) to send and receive data from the Base Station (BS). The PCU was developed as a small hardware unit based on the Microchip microcontroller, with a multiplexer switching two RS 232 serial inputs. One input is dedicated to the GPS receiver and the second one to the wireless modem.

Young, Andrew S.; Skobla, Joseph

2003-08-01

249

Discovery and Integration of Mobile Communications in Everyday Life  

Microsoft Academic Search

We report on the results of a study in which 19 new mobile telephone users were closely tracked for the first six weeks after service acquisition. Results show that novices tend to rapidly modify their perceptions of social appropriateness around mobile phone use, that actual nature of use frequently differs from initial predictions, and that comprehension of service-based technologies can

Leysia Palen; Marilyn C. Salzman; Ed Youngs

2001-01-01

250

Secure Positioning of Mobile Terminals with Simplex Radio Communication  

E-print Network

trusted stations. Our proposal has a major advantage in protecting the location privacy of mobile terminal mobile­phones, PDAs, handheld gaming devices, non­contact IC cards, RFID tags, and GPS receivers, the most popular wireless positioning sys­ tem is perhaps the civilian GPS service, which is orig­ inally

251

Secure Positioning of Mobile Terminals with Simplex Radio Communication  

E-print Network

trusted stations. Our proposal has a major advantage in protecting the location privacy of mobile terminal mobile-phones, PDAs, handheld gaming devices, non-contact IC cards, RFID tags, and GPS receivers, the most popular wireless positioning sys- tem is perhaps the civilian GPS service, which is orig- inally

252

Secure Mobile IP Communication Torsten Braun and Marc Danzeisen  

E-print Network

the paper. 5HODWHG :RUN Zao and Condell discuss the use of IPSec over Mobile IP for HA-MN, HA-FA, CN-HA, CN]. IPSec is used to replace IP-IP-tunneling. Adaptations to Mobile IP messages are proposed for coping with IPSec tunnel establishment. Special IPSec tunnel extensions are added to advertisements and registration

Braun, Torsten

253

Quality of experience of voice communication in large-scale mobile ad hoc networks  

Microsoft Academic Search

Real-time voice communication is an essential requirement in first responder scenarios. While mobile ad hoc networks (MANET) already prove to be an appropriate communication substrate in small-scale real-world operations, questions regarding scalability limitations remain. In this paper, we identify major factors that affect the quality of experience of voice communication in MANETs. In a series of simulation studies, we show

Christian Gottron; A. Konig; M. Hollick; S. Bergstrasser; T. Hildebrandt; R. Steinmetz

2009-01-01

254

[Mobile communication and health of population: estimation of danger, social and ethical problems].  

PubMed

Population lives under new electromagnetic conditions: constant round-the-clock compulsory chronic exposure of all groups of population to modulated wide spectrum of EMF RF during the work of base stations of mobile communication; daily and lifelong (from childhood) exposure of the brain to EMF RF of the mobile phone. Effects of exposure to EMF RF of low levels are presented. Results of research into chronic EMF RF exposure are absent. International recommendations and domestic guidelines do not take into account the changing conditions of EMF RF influence on the population: the brain has become a critical body, and children have been included in the risk group. Population actively continues to use mobile communication. In this situation estimation of the risks from mobile communication has become a social and ethical problem. PMID:21866836

Grigor'ev, Iu G; Grigor'ev, O A

2011-01-01

255

A Mobile Robots Experimental Environment with Event-Based Wireless Communication  

PubMed Central

An experimental platform to communicate between a set of mobile robots through a wireless network has been developed. The mobile robots get their position through a camera which performs as sensor. The video images are processed in a PC and a Waspmote card sends the corresponding position to each robot using the ZigBee standard. A distributed control algorithm based on event-triggered communications has been designed and implemented to bring the robots into the desired formation. Each robot communicates to its neighbors only at event times. Furthermore, a simulation tool has been developed to design and perform experiments with the system. An example of usage is presented. PMID:23881139

Guinaldo, Maria; Fabregas, Ernesto; Farias, Gonzalo; Dormido-Canto, Sebastian; Chaos, Dictino; Sanchez, Jose; Dormido, Sebastian

2013-01-01

256

A mobile robots experimental environment with event-based wireless communication.  

PubMed

An experimental platform to communicate between a set of mobile robots through a wireless network has been developed. The mobile robots get their position through a camera which performs as sensor. The video images are processed in a PC and a Waspmote card sends the corresponding position to each robot using the ZigBee standard. A distributed control algorithm based on event-triggered communications has been designed and implemented to bring the robots into the desired formation. Each robot communicates to its neighbors only at event times. Furthermore, a simulation tool has been developed to design and perform experiments with the system. An example of usage is presented. PMID:23881139

Guinaldo, María; Fábregas, Ernesto; Farias, Gonzalo; Dormido-Canto, Sebastián; Chaos, Dictino; Sánchez, José; Dormido, Sebastián

2013-01-01

257

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

PubMed Central

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

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

2012-01-01

258

Need for, and financial feasibility of, satellite-aided land mobile communications  

NASA Technical Reports Server (NTRS)

Questions regarding the role of a mobile-satellite system in augmenting the terrestrial communications system are considered, and a market assessment study is discussed. Aspects of an investment analysis are examined, taking into account a three phase financial study of four postulated land Mobile Satellite Service (LMSS) systems, project profitability evaluation methods, risk analysis methods, financial projections, potential investor acceptance standards, and a risk analysis. It is concluded that a satellite augmented terrestrial mobile service appears to be economically and technically superior to a service depending exclusively on terrestrial systems. The interest in the Mobile Satellite Service is found to be worldwide, and the ground equipment market is potentially large.

Castruccio, P. A.; Marantz, C. S.; Freibaum, J.

1982-01-01

259

Multimodal ubiquitous localization: a GPS\\/WiFi\\/GSM-based lightweight solution  

Microsoft Academic Search

Localization is a key support service for all users of mobile devices. We envision a lightweight localization service for Smartphones that overcomes the limitations of existing GPS-based approaches, namely their high energy cost and their issues with coverage. Our localization service uses GPS only if available and necessary, and employs other methods, such as WiFi and GSM, to achieve its

Michela Papandrea

2009-01-01

260

The application of surface plethysmography for heart rate variability analysis after GSM radiofrequency exposure  

Microsoft Academic Search

The aim of the present study was to test whether the electromagnetic field emitted by standard GSM mobile phones results in changes in heart rate (HR) and heart rate variability (HRV) of 35 healthy young male and female subjects. Two parallel signals, electrocardiogram and infrared surface plethysmogram were recorded and compared to test their validity for the analysis. Plethysmographic recording

Tamás Atlasz; Lóránd Kellényi; Péter Kovács; Norbert Babai; György Thuróczy; László Hejjel; István Hernádi

2006-01-01

261

Stratus: energy-efficient mobile communication using cloud support  

Microsoft Academic Search

Cellular radio communication is a significant contributor to battery energy drain on smartphones, in some cases inflating the energy cost by a factor of 5 or more compared to the energy cost of the base device. Stratus is a system to reduce this energy consumption by leveraging cloud resources to make data communication on smartphones more efficient. Using a cloud-based

Bhavish Aggarwal; Pushkar Chitnis; Amit Dey; Kamal Jain; Vishnu Navda; Venkata N. Padmanabhan; Ramachandran Ramjee; Aaron Schulman; Neil Spring

2011-01-01

262

Stratus: energy-efficient mobile communication using cloud support  

Microsoft Academic Search

Cellular radio communication is a significant contributor to battery energy drain on smartphones, in some cases inflating the energy cost by a factor of 5 or more compared to the energy cost of the base device. Stratus is a system to reduce this energy consumption by leveraging cloud resources to make data communication on smartphones more efficient. Using a cloud-based

Bhavish Aggarwal; Pushkar Chitnis; Amit Dey; Kamal Jain; Vishnu Navda; Venkata N. Padmanabhan; Ramachandran Ramjee; Aaron Schulman; Neil Spring

2010-01-01

263

Wireless Communications  

NSDL National Science Digital Library

Wireless communications is an industry that is growing at an incredible rate. Cellular phones are the most obvious example of this trend; it is hard to go anywhere without seeing someone using one. Rapidly advancing technologies and lower prices are making this all possible. At the current pace, there seems to be no limit to what is possible in the wireless industry.To learn about the events that led up to present day wireless communications, this site offers a very informative history of telecommunications (1) that goes all the way back to the time of carrier pigeons. A good introduction to wireless networking can be found in this mini-tutorial (2). The best parts of this tutorial are the discussions of many recent wireless developments and technologies. There are a few interactive games and activities that are supposed to be instructive and entertaining, but some of them can be annoying. For the more technically savvy user, the third site (3) starts by describing many of the principles that drive current wireless systems. The second part examines the technologies that will be used in future generations of services. To build on this material, the third generation mobile communications systems (3G) is the central topic at 3G Newsroom (4), providing breaking news about the development of 3G technology. Additionally, the site has an excellent introduction to 3G, including its applications and specifications. One of the advancements that is paving the way toward 3G is Bluetooth, which is explained in great detail here (5). This technology is capable of very high data transfer rates, but there are some limitations, which are all discussed in the articles on the site. Although Bluetooth is raising plenty of interest, this recent news story (6) is creating more than its share of debate. It outlines a very controversial move by the FCC to allow the use of ultrawideband technology in commercial wireless applications. The author explains in simple terms why there are so many concerns about something that could revolutionize wireless systems. The evolution of the global system for mobile communications (GSM) is traced at GSM World (7). Here users can learn about the roots of the wireless industry as well as what is in store for the future. A special section addresses health concerns associated with mobile phone use. Radio was one of the earliest form of wireless communication, and the Invention of Radio (8) documents the people and events that made it what it is today. The stories of such famous scientists and inventors as Marconi, DeForest, and Armstrong are told in brief accounts, and there is even a link to the well known War of the Worlds radio broadcast.

Leske, Cavin.

2002-01-01

264

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

PubMed

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

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

2014-01-01

265

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

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

266

Utilizing Mobility to Minimize the Total Communication and Motion Energy  

E-print Network

the motion decision of the robot. Our simulation results show that, by using our strategy, the robot can in the communications/networking and robotics literature Goldsmith and Chua (1997); Mei et al. (2004), co

Mostofi, Yasamin

267

Autonomous interactive intermediaries : social intelligence for mobile communication agents  

E-print Network

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 ...

Marti, Stefan Johannes Walter, 1965-

2005-01-01

268

Adaptive Transceivers for Mobile Free-Space Optical Communications  

Microsoft Academic Search

Free-space optical (FSO) communication links are susceptible to a tremendous amount of variability and offer a real challenge for efficient, robust system design. Whether changes in link margin are predictable (i.e. weather conditions or mission profiles) or truly random (i.e. atmospheric turbulence induced scintillation or boundary layer induced tracking errors), FSO communication systems will experience a large dynamic range of

Jeffrey R. Minch; David R. Gervais; Daniel J. Townsend

2006-01-01

269

Overview of NASA Glenn Aero/Mobile Communication Demonstrations  

NASA Technical Reports Server (NTRS)

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.

Brooks, David; Hoder, Doug; Wilkins, Ryan

2004-01-01

270

Overview of NASA Glenn Aero/Mobile Communications Demonstrations  

NASA Technical Reports Server (NTRS)

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.

Brooks, David; Hoder, Doug; Wilkins, Ryan

2004-01-01

271

An operational open-end file transfer protocol for mobile satellite communications  

NASA Technical Reports Server (NTRS)

This paper describes an operational open-end file transfer protocol which includes the connecting procedure, data transfer, and relinquishment procedure for mobile satellite communications. The protocol makes use of the frame level and packet level formats of the X.25 standard for the data link layer and network layer, respectively. The structure of a testbed for experimental simulation of this protocol over a mobile fading channel is also introduced.

Wang, Charles; Cheng, Unjeng; Yan, Tsun-Yee

1988-01-01

272

Elevation Dependent Shadowing Model for Mobile Communications via High Altitude Platforms in Built-Up Areas  

Microsoft Academic Search

An empirical propagation prediction model is described for mobile communications from high altitude platforms (HAPs) in different types of built-up areas. The model introduced here is defined as a function of the angle of elevation. The target frequencies are selected from the 2 to 6 GHz frequency band prospective for 3G and 4G mobile systems, namely at 2.0,3.5, and 5.5

Jaroslav Holis; Pavel Pechac

2008-01-01

273

Improving the Communication of Spatial Information in Crisis Response by Combining Paper Maps and Mobile Devices  

Microsoft Academic Search

Efficient and effective communication between mobile units and the central emergency operation center is a key factor to respond\\u000a successfully to the challenges of emergency management. Nowadays, the only ubiquitously available modality is a voice channel\\u000a through mobile phones or radio transceivers. This makes it often very difficult to convey exact geographic locations and can\\u000a lead to misconceptions with severe

Johannes Schöning; Michael Rohs; Antonio Krüger; Christoph Stasch

2008-01-01

274

Mobility-Tolerant Reliable Wireless LAN Multicast Communication  

Microsoft Academic Search

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

V. Shankar; S. K. S. Gupta

275

Diversity techniques for blind channel equalization in mobile communications  

Microsoft Academic Search

A blind algorithm for channel distortion compensation is presented which can be employed in spatial or temporal diversity receivers. The proposed technique can be used in frequency selective and frequency flat fading mobile channels, using burst transmission schemes in the first case and OFDM modulation in the second one. The algorithm is base on a deterministic criteria and is suited

Meritxell Lamarca; G. Vazquez

1997-01-01

276

Improving TCP performance in mobile satellite IP communications  

E-print Network

station or mobile entities to another earth station via artificial satellites Seamless, ubiquitous system: hypertext transfer protocol FTP: file transfer protocol BER: bit error rate #12;June 26, 2006 TMP 2006 issues of wasted bandwidth due to excessive spam (Nigeria, Nepal) #12;June 26, 2006 TMP 2006: Improving

Trajkovic, Ljiljana

277

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

E-print Network

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 ...

Mochizuki, Yujiro, 1973-

2006-01-01

278

An experimental OFDM system for broadband mobile communications  

Microsoft Academic Search

We present an overview of an experimental 20 MHz 2×2 MIMO-OFDM system for operation at 3.65 GHz. The transmitted signal characteristics, data collection setup, measurement analysis, and timing acquisition algorithms are described. Field trials from a base station with two transmit antennas to a two-antenna mobile receiver are planned in a coverage area having a two mile radius. The first

Mickael D. Batariere; James F. Kepler; Thomas P. Krauss; Sandeep Mukthavaram; Jeffrey W. Porter; Frederick W. Vook

2001-01-01

279

Mobile communication higher-order-mode microstrip antennas for VICS  

Microsoft Academic Search

The Vehicle Information and Communication System (VICS) is one of the intelligent transport systems (ITS) in Japan. The system commenced in the Tokyo area and Tohmei and Meishin highways in 1996. VICS consists of a radio beacon system, a light beacon system and an FM broadcasting system. The radio beacon system antennas installed on cars are desired to have the

Y. Kazama; N. Morita; S. Tokumaru

1998-01-01

280

Ultra high frequency (UHF) phononic crystal devices operating in mobile communication bands  

Microsoft Academic Search

Recently phononic crystal slabs operating in the very high frequency (VHF) range have been reported and have gained interest for RF signal processing. This paper reports phononic crystal slabs and devices operating in the commonly used GSM-850 and GSM-900 cellular phone bands, representing nearly an order of magnitude increase in operating frequency compared to the state-of-the-art. Phononic crystals centered at

Roy H. Olsson; Simon X. Griego; I. El-Kady; Mehmet Su; Yasser Soliman; Drew Goettler; Zayd Leseman

2009-01-01

281

Study of LEO-SAT microwave link for broad-band mobile satellite communication system  

NASA Technical Reports Server (NTRS)

In the field of mobile satellite communications, a system based on low-earth-orbit satellites (LEO-SAT's) such as the Iridium system has been proposed. The LEO-SAT system is able to offer mobile telecommunication services in high-latitude areas. Rain degradation, fading and shadowing are also expected to be decreased when the system is operated at a high elevation angle. Furthermore, the propagation delay generated in the LEO-SAT system is less pronounced than that in the geostationary orbit satellite (GEO-SAT) system and, in voice services, the effect of the delay is almost negligible. We proposed a concept of a broad-band mobile satellite communication system with LEO-SAT's and Optical ISL. In that system, a fixed L-band (1.6/1.5 GHz) multibeam is used to offer narrow band service to the mobile terminals in the entire area covered by a LEO-SAT and steerable Ka-band (30/20 GHz) spot beams are used for the wide band service. In this paper, we present results of a study of LEO-SAT microwave link between a satellite and a mobile terminal for a broad-band mobile satellite communication system. First, the results of link budget calculations are presented and the antennas mounted on satellites are shown. For a future mobile antenna technology, we also show digital beamforming (DBF) techniques. DBF, together with modulation and/or demodulation, is becoming a key technique for mobile antennas with advanced functions such as antenna pattern calibration, correction, and radio interference suppression. In this paper, efficient DBF techniques for transmitting and receiving are presented. Furthermore, an adaptive array antenna system suitable for this LEO-SAT is presented.

Fujise, Masayuki; Chujo, Wataru; Chiba, Isamu; Furuhama, Yoji; Kawabata, Kazuaki; Konishi, Yoshihiko

1993-01-01

282

GSM-Railway as part of the European Rail Traffic Management System  

NASA Astrophysics Data System (ADS)

GSM-R is a vital component inside the ERTMS which is also an essential element of European Community rail projects; investment in equipping and the rolling stock with ERTMS could reach 5 billion eurodollars in the period 2007-2016. GSM-R is the result of over ten years of collaboration between the various European railway companies, the railway communication industry and the different standardization bodies. GSM-R provides a secure platform for voice and data communication between the operational staff of the railway companies including drivers, dispatchers, shunting team members, train engineers, and station controllers. It delivers advanced features such as group calls, voice broadcast, location based connections, and call pre-emption in case of an emergency, which significantly improves communication, collaboration, and security management across operational staff members. Taking into account the above mentioned, the paper will permit to audience to discover the GSM-R network architecture, services and applications proposed by this technology together with the future development and market situation due to the market liberalization.

Bibac, Ionut

2007-05-01

283

RESOLUTION: Reconfigurable Systems for Mobile Local Communication and Positioning  

Microsoft Academic Search

RESOLUTION aims at developing a wireless three-dimensional (3-D) local positioning system with measurement accuracy in the centimetre regime and real-time ability. A novel frequency modulated continuous wave (FMCW) radar principle with pulsed active reflector is employed. This High-Precision-Localisation-System (HPLS) will be implemented together with common WLAN systems that are used for data communication purposes. Due to its high data rate

Philippos Tragas; Antonis Kalis; Constantinos Papadias; Frank Ellinger; Ralf Eickhoff; Thomas Ussmuller; Ralf Mosshammer; Mario Huemer; Alexander Dabek; Dimosthenes Doumenis; Anastassios Kounoudes

2007-01-01

284

An adaptive array antenna for mobile satellite communications  

NASA Technical Reports Server (NTRS)

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.

Milne, Robert

1990-01-01

285

The Future Generations of Mobile Communications Based on Broadband Access Methods  

Microsoft Academic Search

The forthcoming mobile communication systems are expected to provide much variety of services from high quality voice to high definition videos through high data rate wireless channels at anywhere in the world. High data rate requires broad frequency bands, and sufficient broadband can be achieved in higher frequency bands such as microwave, Ka-band and millimeter-wave. Broadband wireless channels have to

Shingo Ohmori; Yasushi Yamao; Nobuo Nakajima

2001-01-01

286

Modeling of terrains for simulation of integrated mobile terrestrial and satellite communications systems  

Microsoft Academic Search

In this paper we present methods to generate models of mountainous regions. For these regions statistical methods are unsuitable to predict the service coverage, blocking and termination probabilities for systems involving fast moving satellites. We present methods using modeled terrains to analyze the service coverage in satellite integrated mobile communications systems. Results of service coverage analyses based on these methods

Gunar Schorcht; Ulrich Freund; Horst Salzwedel; Harald Keller

1996-01-01

287

An efficient communication strategy for mobile agent based distributed spatial data mining application  

NASA Astrophysics Data System (ADS)

An efficient communication strategy is proposed in this paper, which aims to improve the response time and availability of mobile agent based distributed spatial data mining applications. When dealing with decomposed complex data mining tasks or On-Line Analytical Processing (OLAP), mobile agents authorized by the specified user need to coordinate and cooperate with each other by employing given communication method to fulfill the subtasks delegated to them. Agent interactive behavior, e.g. messages passing, intermediate results exchanging and final results merging, must happen after the specified path is determined by executing given routing selection algorithm. Most of algorithms exploited currently run in time that grows approximately quadratic with the size of the input nodes where mobile agents migrate between. In order to gain enhanced communication performance by reducing the execution time of the decision algorithm, we propose an approach to reduce the number of nodes involved in the computation. In practice, hosts in the system are reorganized into groups in terms of the bandwidth between adjacent nodes. Then, we find an optimal node for each group with high bandwidth and powerful computing resources, which is managed by an agent dispatched by agent home node. With that, the communication pattern can be implemented at a higher level of abstraction and contribute to improving the overall performance of mobile agent based distributed spatial data mining applications.

Han, Guodong; Wang, Jiazhen

2005-11-01

288

WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2011; 11:16281645  

E-print Network

WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2011; 11 Kumar and Ahmed Kamal Department of Electrical and Computer Engineering, Iowa State University, Ames, IA. Fertilizer uptake and irrigation needs within a field depend on factors that vary in space and time

Kumar, Ratnesh

289

Eye Contact Communication System between Mobile Robots Using Invisible Code Display  

E-print Network

Eye Contact Communication System between Mobile Robots Using Invisible Code Display Takeru Furukawa on displays which show an expression of robot's eyes. Keywords: 2D code, polarized invisible code, polarized light control, LCD display 1 Introduction "The eyes are eloquent as the tongue." This proverb means

Paris-Sud XI, Université de

290

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

ERIC Educational Resources Information Center

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…

Jones, Geraldine; Edwards, Gabriele; Reid, Alan

2009-01-01

291

Cross Layer Design for Mobile Ad-Hoc Unmanned Aerial Vehicle Communication Networks  

E-print Network

Cross Layer Design for Mobile Ad-Hoc Unmanned Aerial Vehicle Communication Networks Abdel Ilah of the Unmanned Aerial Vehicle (UAV) Ad-Hoc net- work, the layered architecture is not flexible enough to achieve for Unmanned Aerial Vehicle (IMAC UAV). As for the routing protocol, We developed the Optimized Link State

Dong, Liang

292

Power Saving with p-Persistent Sleep Decision for Ubiquitous Mobile Communications  

Microsoft Academic Search

Battery power is an important and limited resource in ubiquitous mobile communications. Energy consumption can be reduced by turning off the radio during idle times. In most power saving schemes, a node decides whether to put its wireless interfaces in the sleep state or in an awake state, based only on the presence of packets destined for the node. However,

Ji Wun Lee; Wha Sook Jeon; Dong Geun Jeong

2006-01-01

293

Development and performance of an L-band phased array antenna for mobile satellite communications  

Microsoft Academic Search

The previous years have witnessed an introduction of a large number of mobile satellite (MSS) communications systems. These include a global GEO MSS system, Inmarsat, and domestic GEO MSS systems such as North-American AMSC, Japan's N-Star and the Australian Mobilesat. At present, two types of antennas can be used to access GEO MSS services. They include (1) fixed position antennas,

N. C. Karmakar; M. E. Bialkowskilr

1999-01-01

294

WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2009; 9:110  

E-print Network

Media and Communications, Seoul National University, Seoul, Republic of Korea Summary Inwirelessnetworks consumption should be minimized in order to prolong the battery lifetime of the mobile station (MS consumption. Copyright © 2009 John Wiley & Sons, Ltd. KEY WORDS: elastic traffic; throughput; energy saving

Bahk, Saewoong

295

New adaptive beamforming algorithms for smart antennas in DS-CDMA mobile communication systems  

Microsoft Academic Search

The increasing capacity and quality demands for mobile communication services, without a corresponding increase in RF spectrum allocation, motivate the need for new techniques to improve spectrum utilization. The CDMA and SDMA (spatial division multiple access) technologies are two solutions that show real promise for increasing spectrum efficiency. This work investigated smart antenna adaptive beamforming algorithms to implement and combine

Vu Dinh Thanh; Nguyen Le Hung

2004-01-01

296

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

E-print Network

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

Latchman, Haniph A.

297

A digital platform for marketing communications in the mobile and social media space  

E-print Network

A digital platform for marketing communications in the mobile and social media space Otto PetrovicPhone and Android, iPad apps, e-mail, RSS feeds and social media. All that channels are used and controlled from of all internet users already use social media regularly and time that is spent increases three times

Boyer, Edmond

298

Enhancing Motivation in Online Courses with Mobile Communication Tool Support: A Comparative Study  

ERIC Educational Resources Information Center

Mobile technologies have helped establish new channels of communication among learners and instructors, potentially providing greater access to course information, and promoting easier access to course activities and learner motivation in online learning environments. The paper compares motivation between groups of learners being taught through an…

Chaiprasurt, Chantorn; Esichaikul, Vatcharaporn

2013-01-01

299

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

NASA Technical Reports Server (NTRS)

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.

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

1991-01-01

300

IEEE COMMUNICATIONS SURVEYS & TUTORIALS, VOL. 12, NO. 1, FIRST QUARTER 2010 1 Route Optimization in Network Mobility: Solutions,  

E-print Network

Engineering Manuscript received ; revised . The research reported in this article was funded by NASA Grant NNX) handles mobility of a set of mobile nodes in an aggregate way using one or more mobile routers. NEMO needs to obtain a new IP address, and therefore, communication may become inefficient while maintaining

Atiquzzaman, Mohammed

301

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

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

302

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

PubMed

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

Muthukumar, M

2014-08-28

303

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

NASA Astrophysics Data System (ADS)

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.

Muthukumar, M.

2014-08-01

304

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

PubMed Central

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

Muthukumar, M.

2014-01-01

305

Performance analysis of replication ALOHA for fading mobile communications channels  

NASA Technical Reports Server (NTRS)

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.

Yan, Tsun-Yee; Clare, Loren P.

1986-01-01

306

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

E-print Network

-layer communication among multiple protocol entities (PEs), assuming the standard ISO/OSI Reference ModelMobile Networks and Applications 2 (1997) 285­301 285 Communication protocol design to facilitate formal descriptions for communication protocols and the effective development methodologies used

Khan, Javed I.

307

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

E-print Network

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

Murray, Richard M.

308

An improved water-filling algorithm for mobile MIMO communication systems over time-varying fading channels  

Microsoft Academic Search

Multiple input multiple output (MIMO) systems that use antenna arrays at both the transmitter and receiver are gaining much more attention and efforts in wireless communication research due to their potential to increase considerably capacity in mobile cellular communications. However, in the real propagation environment of cellular communications, it is difficult to gain the ideal ergodic capacity for time-varying fading

Ligang Ren; Zhijie Yan; Mei Song; Junde Song

2004-01-01

309

Effects of GSM 900 MHz on middle cerebral artery blood flow assessed by transcranial Doppler sonography.  

PubMed

Mobile phone use has increased worldwide but its possible effects on the brain remain unclear. The aim of the present study was to investigate the effect of acute exposure to a radio frequency electromagnetic field (RF EMF) generated by a mobile phone operating in the Global System for Mobile Communication (GSM) 900 MHz on cerebral blood flow. Twenty-nine volunteers attended two experimental sessions: a sham exposure session and a real exposure session in a cross-over double-blind study in which a mobile phone was positioned on the left side of the head. In one session, the mobile phone was operated without RF radiation (sham phone) and in the other study it was operated with RF radiation (real phone) for 20 min. Thus, each subject served as its own control. Middle cerebral artery blood flow was monitored noninvasively by transcranial Doppler sonography to measure middle cerebral artery blood flow velocity. Pulsatility index and resistance index were also evaluated. A voluntary breath holding physiological test was carried out as a positive control for testing cerebral vasoreactivity. Hemodynamic variables were recorded and analyzed before, during and after mobile phone exposure. No significant changes were detected in studied variables in middle cerebral arteries during sham or real exposure. In the exposed side the cerebral blood flow velocity, the pulsatility index and the resistance index during sham and real exposure were respectively: [61.9 ± 1.3, 61.7 ± 1.3 cm/s (P = 0.89)]; [0.93 ± 0.03, 0.90 ± 0.02 (P = 0.84)] and [0.58 ± 0.01, 0.58 ± 0.01 (P = 0.96)] at baseline; and [60.6 ± 1.3, 62 ± 1.6 cm/s (P = 0.40)]; [0.91 ± 0.03, 0.87 ± 0.03 (P = 0.97)]; [0.57 ± 0.01, 0.56 ± 0.01 (P = 0.82)] after 20 min of exposure. Twenty minutes of RF exposure to a mobile phone does not seem to affect the cerebral circulation. PMID:23106209

Ghosn, Rania; Thuróczy, György; Loos, Nathalie; Brenet-Dufour, Valérie; Liabeuf, Sophie; de Seze, René; Selmaoui, Brahim

2012-12-01

310

Modems for emerging digital cellular-mobile radio system  

NASA Technical Reports Server (NTRS)

Digital modem techniques for emerging digital cellular telecommunications-mobile radio system applications are described and analyzed. In particular, theoretical performance, experimental results, principles of operation, and various architectures of pi/4-QPSK (pi/4-shifted coherent or differential QPSK) modems for second-generation US digital cellular radio system applications are presented. The spectral/power efficiency and performance of the pi/4-QPSK modems (American and Japanese digital cellular emerging standards) are studied and briefly compared to GMSK (Gaussian minimum-shift keying) modems (proposed for European DECT and GSM cellular standards). Improved filtering strategies and digital pilot-aided (digital channel sounding) techniques are also considered for pi/4-QPSK and other digital modems. These techniques could significantly improve the performance of digital cellular and other digital land mobile and satellite mobile radio systems. More spectrally efficient modem trends for future cellular/mobile (land mobile) and satellite communication systems applications are also highlighted.

Feher, Kamilo

1991-01-01

311

Proactive TCP mechanism to improve Handover performance in Mobile Satellite and Terrestrial Networks  

E-print Network

Emerging standardization of Geo Mobile Radio (GMR-1) for satellite system is having strong resemblance to terrestrial GSM (Global System for Mobile communications) at the upper protocol layers and TCP (Transmission Control Protocol) is one of them. This space segment technology as well as terrestrial technology, is characterized by periodic variations in communication properties and coverage causing the termination of ongoing call as connections of Mobile Nodes (MN) alter stochastically. Although provisions are made to provide efficient communication infrastructure this hybrid space and terrestrial networks must ensure the end-to-end network performance so that MN can move seamlessly among these networks. However from connectivity point of view current TCP performance has not been engineered for mobility events in multi-radio MN. Traditionally, TCP has applied a set of congestion control algorithms (slow-start, congestion avoidance, fast retransmit, fast recovery) to probe the currently available bandwidth on...

Vinayakray-Jani, Preetida

2012-01-01

312

Mobile Media Devices and Communication Applications as a Form of Augmentative and Alternative Communication: An Assessment of Family Wants, Needs, and Preferences  

E-print Network

This study assessed the wants, needs, and preferences of families at various stages of the decision-making process relative to mobile media technology as a form of augmentative and alternative communication (AAC). A survey entitled "iDevices, AAC...

Meder, Allison

2012-05-31

313

Towards Efficient Mobile M2M Communications: Survey and Open Challenges  

PubMed Central

Machine-to-Machine (M2M) communications enable networked devices and services to exchange information and perform actions seamlessly without the need for human intervention. They are viewed as a key enabler of the Internet of Things (IoT) and ubiquitous applications, like mobile healthcare, telemetry, or intelligent transport systems. We survey existing work on mobile M2M communications, we identify open challenges that have a direct impact on performance and resource usage efficiency, especially the impact on energy efficiency, and we review techniques to improve communications. We review the ETSI standard and application protocols, and draw considerations on the impact of their use in constrained mobile devices. Nowadays, smartphones are equipped with a wide range of embedded sensors, with varied local and wide area connectivity capabilities, and thus they offer a unique opportunity to serve as mobile gateways for other more constrained devices with local connectivity. At the same time, they can gather context data about users and environment from the embedded sensors. These capabilities may be crucial for mobile M2M applications. Finally, in this paper, we consider a scenario where smartphones are used as gateways that collect and aggregate data from sensors in a cellular network. We conclude that, in order for their use to the feasible in terms of a normal depletion time of a smartphone's battery, it is a good advice to maximize the collection of data necessary to be transmitted from nearby sensors, and maximize the intervals between transmissions. More research is required to devise energy efficient transmission methods that enable the use of smartphones as mobile gateways. PMID:25333291

Pereira, Carlos; Aguiar, Ana

2014-01-01

314

Mobile Learning: The Significance of New Mobile and Wireless Communications Technologies for Education  

Microsoft Academic Search

\\u000a At present, the popular perception of mobile telephones in the UK, including the education sector, is generally negative:\\u000a they are perceived as a nuisance and distraction (Stone, 2002, p. 262).\\u000a \\u000a \\u000a The image of schoolchildren staring out of the classroom window, minds preoccupied with daydreams, could be supplanted by\\u000a one of students staring forward — not daydreaming but interacting with vibrating

Gerard Goggin

315

GSM Network Based Z-axis Position Control System  

Microsoft Academic Search

This paper presents the design of a GSM network based z-axis position controlling system for remote monitoring and control. Using this positioning system the height of an object can be controlled and monitored through SMS from any location where GSM network is available. The desired position of an object is sent to the GSM modem by the user through SMS.

S. Hemnath; V. Sridevi

2009-01-01

316

Land mobile communications satellite missions (LAMOCOSAMIS) task 4: Hybrid system concept  

NASA Astrophysics Data System (ADS)

The possibility of a hybrid satellite/terrestrial network for land mobile communication in Europe was assessed. The interdependency of the system parameters makes the problem of satellite mission difficult to approach, and the regulatory context (no frequency allocation for land mobile satellite service in Europe) offers more fields of investigation, as UHF and L-Band have to be considered as candidate frequency bands. It is shown that in L-Band, a capacity of 100 telephone channels is possible with spacecraft of the EUROSTAR class, indicating that a hybrid concept is attractive.

1985-12-01

317

Land mobile satellite communication system. Volume 3: Annexes to volume 2: Particular aspects of market analyses  

NASA Astrophysics Data System (ADS)

The socioeconomic desirability in terms of market demand, technical economic feasibility, and price-performance for a Land Mobile Communication system ground based and/or satellite aided, able to satisfy the request of the traffic demand, foreseeable in the 1995 to 2005 time frame, for the Western European countries was assessed. The criterion of economic value of the mobile system is considered as the driving element. Data on traffic; socioeconomic factors; economic factors; and radiotelephony, paging, and dispatch subscription and value for money trends are presented.

Carnebianca, C.; Pavesi, B.; Tuozzi, A.; Capone, R.

1986-06-01

318

Communication Systems last lecture  

E-print Network

1 | 70 Communication Systems last lecture Chair of Communication Systems Department of Applied Sciences University of Freiburg 2009 #12;2 | 70 Communication Systems final lecture Start with last part, power control and hand-over ­ Authentication and security #12;3 | 70 Communication Systems GSM

Schindelhauer, Christian

319

Maintaining communication link based on AODV routing protocol in mobile robot networks  

NASA Astrophysics Data System (ADS)

Wired computer networks are vital in modern life. However, these networks are extremely vulnerable to disaster or attack in emergency situations. Therefore, how to maintain communication link under emergency situations is very important. In this paper, we utilize a series of autonomous mobile slave robots which follow behind the lead robot and automatically stop where needed to maintain an ad hoc network for guaranteeing a link between the lead robot and its remote monitor/control station. To accomplish this target, an efficient communication protocol limitation mobile robots broadcast based on AODV (LMRB-AODV) is proposed for deployment in multi-robot system. After then the lead robot could carry service traffics to the monitor station under emergency situations through the communication link. At any instance, the lead robot has the ability to reclaim the relay robot(s) which are unneeded in the network to rejoin the convoy behind the lead robot and use it to extend the range of wireless communication when the radio frequency (RF) shortcuts are detected by the lead robot. All relay deployment and reclaiming strategy functions occur without the operator's involvement. Finally, we provide a comparative study of their performance in a number of different simulation environments. The results show that the proposed scheme is very efficient in maintaining communication link in wireless network.

Hu, Hui; Jiang, Hong

2007-12-01

320

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

NASA Technical Reports Server (NTRS)

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.

1989-01-01

321

Issues for the integration of satellite and terrestrial cellular networks for mobile communications  

NASA Technical Reports Server (NTRS)

Satellite and terrestrial cellular systems naturally complement each other for land mobile communications, even though present systems have been developed independently. The main advantages of the integrated system are a faster wide area coverage, a better management of overloading traffic conditions, an extension to geographical areas not covered by the terrestrial network and, in perspective, the provision of only one integrated system for all mobile communications (land, aeronautical, and maritime). To achieve these goals, as far as possible the same protocols of the terrestrial network should be used also for the satellite network. Discussed here are the main issues arising from the requirements of the main integrated system. Some results are illustrated, and possible future improvements due to technical solutions are presented.

Delre, Enrico; Mistretta, Ignazio; Dellipriscoli, Francesco; Settimo, Franco

1991-01-01

322

Performance of the unique-word-reverse-modulation type demodulator for mobile satellite communications  

Microsoft Academic Search

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

Tomohiro Dohi; Kazumasa Nitta; Takashi Ueda

1993-01-01

323

The future generations of mobile communications based on broadband access technologies  

Microsoft Academic Search

The forthcoming mobile communication systems are expected to provide a wide variety of services, from high-quality voice to high-definition videos, through high data rate wireless channels anywhere in the world. The high data rate requires broad frequency bands, and sufficient broadband can be achieved in higher frequency bands such as microwave, Ka-band, and millimeter-wave. Broadband wireless channels have to be

Shingo Ohmori; Yasushi Yamao; Nobuo Nakajima

2000-01-01

324

Cooperative signal reception and down-link beam forming in cellular mobile communications  

Microsoft Academic Search

A cooperative signal reception and down-link beam-forming algorithm is proposed for mobile communication systems employing phase-shift-keying (PSK) modulation. Down-link beam optimality is defined as maximizing the desired reference user's average received power while keeping the noise power plus total amount of average powers received by other users less than or equal to a certain constant level. The proposed algorithm requires

Hiromitsu Asakura; Tadashi Matsumoto

1999-01-01

325

Signal recognition and signature code acquisition in CDMA mobile packet communications  

Microsoft Academic Search

Fast and reliable signal sense and signature code synchronization for direct-sequence spread-spectrum (DS-SS) signals are key issues in the design of the receiver for modern packet code-division multiple-access (CDMA) radio networks for mobile communications; this motivates the study of the signal recognition and code-acquisition (SR\\/CA) scheme we describe in this paper. Specifically, starting from elementary estimation and detection theory criteria,

Riccardo De Gaudenzi; Filippo Giannetti; Marco Luise

1998-01-01

326

Tantalisingly Close: An Archaeology of Communication Desires in Discourses of Mobile Wireless Media  

Microsoft Academic Search

While many studies on mobile wireless communication devices predominantly take a micro-scale approach and concentrate their often ethnographically informed focus on use values, social implications, conversation strategies, changing norms and ethics, culture-dependent domestication, and so forth, with this Ph.D. dissertation I propose to venture into a more historical and comparative direction, mainly in order to shed light on and engage

I. O. de Vries

2008-01-01

327

A linear array antenna using bifilar helical elements for mobile satellite communications  

Microsoft Academic Search

In mobile satellite communication systems such as the AMSC\\/TMI system [Lunsford et al., 1992], circularly polarized omni-directional antennas are attractive for vehicle antennas because any satellite tracking mechanism in the azimuth direction is not necessary for these antennas [Ohmori, 1991]. As one type of omni-directional antenna, a bifilar helical antenna has been proposed [Nakano et al., 1991]. This antenna is

Yoshihiko KONISHI; Masataka OHTSUKA; Makoto MATSUNAGA; Takashi KATAGI

1994-01-01

328

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

NASA Technical Reports Server (NTRS)

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.

Ames, William G.

1990-01-01

329

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

NASA Astrophysics Data System (ADS)

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.

Ames, William G.

330

Effect of a chronic GSM 900 MHz exposure on glia in the rat brain.  

PubMed

Extension of the mobile phone technology raises concern about the health effects of 900 MHz microwaves on the central nervous system (CNS). In this study we measured GFAP expression using immunocytochemistry method, to evaluate glial evolution 10 days after a chronic exposure (5 days a week for 24 weeks) to GSM signal for 45 min/day at a brain-averaged specific absorption rate (SAR)=1.5 W/kg and for 15 min/day at a SAR=6 W/kg in the following rat brain areas: prefrontal cortex (PfCx), caudate putamen (Cpu), lateral globus pallidus of striatum (LGP), dentate gyrus of hippocampus (DG) and cerebellum cortex (CCx). In comparison to sham or cage control animals, rats exposed to chronic GSM signal at 6 W/kg have increased GFAP stained surface areas in the brain (p<0.05). But the chronic exposure to GSM at 1.5 W/kg did not increase GFAP expression. Our results indicated that chronic exposure to GSM 900 MHz microwaves (SAR=6 W/kg) may induce persistent astroglia activation in the rat brain (sign of a potential gliosis). PMID:18424058

Ammari, Mohamed; Brillaud, Elsa; Gamez, Christelle; Lecomte, Anthony; Sakly, Mohsen; Abdelmelek, Hafedh; de Seze, René

2008-01-01

331

Managing Communication Availability and Interruptions: A Study of Mobile Communication in an Oncology Department  

Microsoft Academic Search

Wireless phones and text messaging are tremendously popular in many areas of society. However, they are still relatively unused in hospitals where pagers are a pervasive communication device that is notoriously difficult to replace. This paper studies pager and wireless phone use at the oncology de- partment at University Hospital of North Norway. Participatory observation and interviews with physicians are

Jeremiah Scholl; Per Hasvold; Eva Henriksen; Gunnar Ellingsen

2007-01-01

332

Satellite-aided mobile communications limited operational test in the trucking industry  

NASA Technical Reports Server (NTRS)

An experiment with NASA's ATS-6 satellite, that demonstrates the practicality of satellite-aided land mobile communications is described. Satellite communications equipment for the experiment was designed so that it would be no more expensive, when mass produced, than conventional two-way mobile radio equipment. It embodied the operational features and convenience of present day mobile radios. Vehicle antennas 75 cm tall and 2 cm in diameter provided good commercial quality signals to and from trucks and jeeps. Operational applicability and usage data were gathered by installing the radio equipment in five long-haul tractor-trailer trucks and two Air Force search and rescue jeeps. Channel occupancy rates are reported. Air Force personnel found the satellite radio system extremely valuable in their search and rescue mission during maneuvers and actual rescue operations. Propagation data is subjectively analyzed and over 4 hours of random data is categorized and graded as to signal quality on a second by second basis. Trends in different topographic regions are reported. An overall communications reliability of 93% was observed despite low satellite elevation angles ranging from 9 to 24 degrees.

Anderson, R. E.; Frey, R. L.; Lewis, J. R.

1980-01-01

333

Broadband and scalable mobile satellite communication system for future access networks  

NASA Astrophysics Data System (ADS)

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.

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

2005-07-01

334

Studies on tumor incidence in mice exposed to GSM cell-phone radiation [Health Effects  

Microsoft Academic Search

This paper studies on tumor incidence in mice exposed to GSM cell-phone radiation. The first study of lymphomas in female Emu_Pim1 transgenic mice using frequencies and modulations specific to cellular mobile phones was conducted in Australia in which the incidence was shown to be significantly higher (odds ratio, OR = 2.4) in the exposed mice (43%) than in the sham

James C. Lin

2008-01-01

335

Practical Context Awareness for GSM Cell Phones  

Microsoft Academic Search

The ability to provide context aware behaviour on a cell phone such as whether a user is walking or driving has previously only been possible via the use of additional hardware sensors such as an accelerometer. In this paper we show that by using GSM data such as signal strength fluctuation and changes to the monitored neighbouring cells it is

Ian Anderson; Henk L. Muller

2006-01-01

336

Experiment Plan of ETS-8 in Orbit : Mobile Communications and Navigation  

NASA Astrophysics Data System (ADS)

The experiment of S-Band Mobile Communications/Broadcasting and L/S-Band Satellite Navigation is the main objectives of Engineering Test Satellite - 8 (ETS-8), which will be launched in 2004 into geostationary orbit at 146 degree East. In this paper, the basic experiment plan is described. After the function tests of satellite in orbit, participation of those who have interest in this experiment are welcome. For the mobile communications/broadcasting, two deployable reflectors (17 meter x 19 meter, each) and 400 W class active phased array feeder with 31 SSPAs are installed in ETS-8. Three beams are used simultaneously to cover Japan and neighbor region. Two kinds of onboard processors are also installed, that are for voice and high-speed packet communication, respectively. The ground terminal for voice communications is as small as conventional cellar phone, and that for packet is similar size of notebook type PC. For satellite navigation, two Cesium clocks are installed. The coverage area is Asia -Pacific hemisphere. The experiment will be conducted by use of ground stations and signals from GPS.The positioning accuracy is evaluated by changing RF frequency, code pattern and chip rate. To determine the precise orbital parameters of satellite, laser ranging of satellite is planned in cooperation with foreign institutes.

Homma, M.; Hama, S.; Kohata, H.

2002-01-01

337

An overview of the technical design of MSAT mobile satellite communications services  

NASA Astrophysics Data System (ADS)

The Canadian MSAT mobile satellite communications system is being implemented in cooperation with the American Mobile Satellite Consortium (AMSC). Two satellites are to be jointly acquired and each satellite is expected to backup the other. This paper describes the technical concepts of the services to be offered and the baseline planning of the infrastructure for the ground segment. MSAT service requirements are analyzed for mobile radio, telephone, data, and aeronautical services. The MSAT system will use nine beams in a narrow range of L-band frequencies with frequency reuse. Beams may be added to cover flight information areas in the Atlantic and Pacific oceans. The elements of the network architecture are: a network control centre, data hub stations, gateway stations, base stations, mobile terminals, and a signalling system to interconnect the elements of the system. The network control center will manage the network and allocate space segment capacity; data hub stations will support a switched packet mobile data service; the gateway stations will provide interconnection to the public telephone system and data networks; and the base stations will support private circuit switched voice and data services. Several alternative designs for the signalling system are described.

Davies, N. George

338

Mobile Communication and Civil Society: Linking Patterns and Places of Use to Engagement with Others in Public  

ERIC Educational Resources Information Center

This study examined whether and how mobile communication influences the extent to which one engages with new people in public settings. Contrary to our expectation, general use of the technology in public did not detract from conversing with strangers. Shifting focus from "where" one uses the mobile phone to "how" it is used, we found that uses…

Campbell, Scott W.; Kwak, Nojin

2011-01-01

339

202 IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 49, NO. 1, JANUARY 2000 Effect of Mobile Velocity on Communications in  

E-print Network

on the performance of a communication system operating in a multi- path fading channel. To incorporate the effect202 IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 49, NO. 1, JANUARY 2000 Effect of Mobile Velocity on Communications in Fading Channels Michael J. Chu, Student Member, IEEE, and Wayne E. Stark

340

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

NASA Technical Reports Server (NTRS)

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.

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

1990-01-01

341

Statistically validated mobile communication networks: Evolution of motifs in European and Chinese data  

E-print Network

Big data open up unprecedented opportunities to investigate complex systems including the society. In particular, communication data serve as major sources for computational social sciences but they have to be cleaned and filtered as they may contain spurious information due to recording errors as well as interactions, like commercial and marketing activities, not directly related to the social network. The network constructed from communication data can only be considered as a proxy for the network of social relationships. Here we apply a systematic method, based on multiple hypothesis testing, to statistically validate the links and then construct the corresponding Bonferroni network, generalized to the directed case. We study two large datasets of mobile phone records, one from Europe and the other from China. For both datasets we compare the raw data networks with the corresponding Bonferroni networks and point out significant differences in the structures and in the basic network measures. We show eviden...

Li, Ming-Xia; Jiang, Zhi-Qiang; Kaski, Kimmo; Kertész, Janos; Miccichč, Salvatore; Tumminello, Michele; Zhou, Wei-Xing; Mantegna, Rosario N

2014-01-01

342

Experiment Plan of ETS-8 in orbit: Mobile communications and navigation  

NASA Astrophysics Data System (ADS)

The experiment of mobile communications and broadcasting by S-band and the satellite navigation by L/S-band are the main objectives of Engineering Test Satellite - 8 (ETS-8), which will be launced in 2004 into geostationary orbit at 146 degree East. In this paper, the current status of ETS-8 is introduced at first and the basic experiment plan is described. For the mobile communications/broadcasting, two deployable reflectors (17 meters × 19 meters, each) and a 400 W class active phased array feeder with 31 SSPAs are installed in ETS-8. Three beams are used simultaneously to cover Japan and neighbor region. Two kinds of onboard processors are also installed, which are dedicated to voice and high-speed packet communication, respectively. The ground terminal for voice communications is as small as conventional cellular phone, and that for packet is similar size of notebook type PC. For satellite navigation, two Cesium clocks are installed. The coverage area is Asia-Pacific hemisphere. The experiment will be conducted by use of ground stations and signals from GPS. The positioning accuracy is evaluated by changing RF frequency, code pattern and chip rate. To determine the precise orbital parameters of satellite, the laser ranging method is adopted. This satellite navigation experiment will be conducted in cooperation with foreign and domestic institutes. After the funtion tests of satellite in orbit, it will be from 2005 year, the opportunity to conduct some experiment used of ETS-8 will provide. The participation of those who have interest in these experiments is welcome.

Homma, M.; Hama, S.; Kohata, H.; Hamamoto, N.; Tanaka, M.

2003-08-01

343

7 CFR 1493.6 - Additional required determinations for GSM-103.  

Code of Federal Regulations, 2010 CFR

... Additional required determinations for GSM-103. 1493.6 Section 1493.6 ...Additional required determinations for GSM-103. Notwithstanding any other provision...part, CCC shall not guarantee under the GSM-103 program the repayment of...

2010-01-01

344

7 CFR 1493.6 - Additional required determinations for GSM-103.  

Code of Federal Regulations, 2011 CFR

... Additional required determinations for GSM-103. 1493.6 Section 1493.6 ...Additional required determinations for GSM-103. Notwithstanding any other provision...part, CCC shall not guarantee under the GSM-103 program the repayment of...

2011-01-01

345

Statistically validated mobile communication networks: the evolution of motifs in European and Chinese data  

NASA Astrophysics Data System (ADS)

Big data open up unprecedented opportunities for investigating complex systems, including society. In particular, communication data serve as major sources for computational social sciences, but they have to be cleaned and filtered as they may contain spurious information due to recording errors as well as interactions, like commercial and marketing activities, not directly related to the social network. The network constructed from communication data can only be considered as a proxy for the network of social relationships. Here we apply a systematic method, based on multiple-hypothesis testing, to statistically validate the links and then construct the corresponding Bonferroni network, generalized to the directed case. We study two large datasets of mobile phone records, one from Europe and the other from China. For both datasets we compare the raw data networks with the corresponding Bonferroni networks and point out significant differences in the structures and in the basic network measures. We show evidence that the Bonferroni network provides a better proxy for the network of social interactions than the original one. Using the filtered networks, we investigated the statistics and temporal evolution of small directed 3-motifs and concluded that closed communication triads have a formation time scale, which is quite fast and typically intraday. We also find that open communication triads preferentially evolve into other open triads with a higher fraction of reciprocated calls. These stylized facts were observed for both datasets.

Li, Ming-Xia; Palchykov, Vasyl; Jiang, Zhi-Qiang; Kaski, Kimmo; Kertész, János; Miccichč, Salvatore; Tumminello, Michele; Zhou, Wei-Xing; Mantegna, Rosario N.

2014-08-01

346

Images of Men and Women in Mobile Phone Advertisements: A Content Analysis of Advertisements for Mobile Communication Systems in Selected Popular Magazines  

Microsoft Academic Search

The present study was designed to analyze gender stereotypes in print advertisements for mobile communication systems in German popular magazines intended for men, women, and general readership. Depictions of both women and men are addressed. A total of 288 depictions were examined using Goffman’s (Gender advertisements, Harvard University Press, Cambridge, Massachusetts, 1979) framework for content analysis. Other variables studied were

Nicola Döring; Sandra Pöschl

2006-01-01

347

A narrowband tactical communication system for the VHF and UHF mobile radio bands  

NASA Astrophysics Data System (ADS)

A description of the research effort, performed in accordance with a National Defense (DND) sponsored Research Program, is presented. Goals fixed for the program aim at achieving good quality, encryptable voice communications in the VHF and UHF mobile bands within a channel spacing of about 3 kHz. A review of the desirable performance objectives of a land-mobile tactical voice communications system is presented, and the design strategy suggested to achieve this performance is described. Implementation includes the use of techniques such as frequency domain digital signal processing of single sideband speech, speech bandwidth reduction, and linear modulation. A study, and in some cases experimental evaluation, on promising bandwidth reduction techniques was done, and a method, called the dynamic frequency band extraction technique, was developed for this application. With this technique, a good voice quality is obtained by dynamically saving only about 1200 Hz of the original 3000 Hz voice spectrum. Taking into account the extra bandwidth required by the data, the frequency domain filtering, and the pulse shaping of the discrete-time samples, and using a highly linear power amplifier, the RF channel spacing of the modulated signal is expected to be approx. of 2.5 kHz.

Boucher, L.; Jolly, Y.; Lodge, J. H.

1989-12-01

348

Radio resource and mobility management in GPRS network  

Microsoft Academic Search

The General Packet Radio Service (GPRS) is a complex data network which upgrades current second generation GSM networks, offering true high-speed Internet (IP) and X.25 network connectivity over existing GSM cellular networks. The key benefits of GPRS are better use of radio and network resources and completely transparent IP support. The increasing population of mobile users leads to congestion problems

Murugan Krishnan; Mahamod Ismail; Khairil Annuar

2002-01-01

349

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

PubMed

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

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

2014-01-01

350

Place-Based Attributes Predict Community Membership in a Mobile Phone Communication Network  

PubMed Central

Social networks can be organized into communities of closely connected nodes, a property known as modularity. Because diseases, information, and behaviors spread faster within communities than between communities, understanding modularity has broad implications for public policy, epidemiology and the social sciences. Explanations for community formation in social networks often incorporate the attributes of individual people, such as gender, ethnicity or shared activities. High modularity is also a property of large-scale social networks, where each node represents a population of individuals at a location, such as call flow between mobile phone towers. However, whether or not place-based attributes, including land cover and economic activity, can predict community membership for network nodes in large-scale networks remains unknown. We describe the pattern of modularity in a mobile phone communication network in the Dominican Republic, and use a linear discriminant analysis (LDA) to determine whether geographic context can explain community membership. Our results demonstrate that place-based attributes, including sugar cane production, urbanization, distance to the nearest airport, and wealth, correctly predicted community membership for over 70% of mobile phone towers. We observed a strongly positive correlation (r?=?0.97) between the modularity score and the predictive ability of the LDA, suggesting that place-based attributes can accurately represent the processes driving modularity. In the absence of social network data, the methods we present can be used to predict community membership over large scales using solely place-based attributes. PMID:23451034

Caughlin, T. Trevor; Ruktanonchai, Nick; Acevedo, Miguel A.; Lopiano, Kenneth K.; Prosper, Olivia; Eagle, Nathan; Tatem, Andrew J.

2013-01-01

351

Requirements for a mobile communications satellite system. Volume 1: Executive summary  

NASA Technical Reports Server (NTRS)

Three types of satellite-aided mobile communications are considered for users in areas not served by (terrestrial) cellular radio systems. In System 1, mobile units are provided a direct satellite link to a gateway station, which serves as the interface to the terrestrial toll network. In System 2, a terrestrial radio link similar to those in cellular systems connects the mobile unit to a translator station; each translator relays the traffic from mobile units in its vicinity, via satellite, to the regional gateway. It is not feasible for System 2 to provide ubiquitous coverage. Therefore, System 3 is introduced, in which the small percentage of users not within range of a translator are provided a direct satellite link as in System 1. While System 2 can operate with leased satellite capacity, Systems 1 and 3 require a dedicated satellite. A major portion of this study is concerned with the design of a satellite for System 1. A weight limit of 10,000 lbs, corresponding to the projected 1990 STS capability, is imposed on the design. Frequency re-use of the allocated spectrum, through multiple satellite beams, is employed to generate the specified system capacity. Both offset-fed and center-fed reflectors are considered. For an assumed 10-MHz allocation and a population of 350,000 subscribers, a two-satellite system is required. The reflector diameters corresponding to offset-fed and center-fed geometries are 46 m and 62 m, respectively. Thus, large-space-structure technology is inherent to the implementation of System 1. In addition to establishing the technical requirements for the three types of satellite systems, the monthly service charge needed to provide a specified return on invested capital is computed. A net present value analysis is used for this purpose.

1983-01-01

352

Technical characteristics of the OmniTRACS: The first operation mobile Ku-band satellite communications system  

NASA Technical Reports Server (NTRS)

The techinical characteristics of the OmniTRACS system are described. The system is the first operational mobile Ku-band satellite communications system and provides two-way message and position determination service to mobile terminals using existing Ku-band satellites. Interference to and from the system is minimized by the use of special spread-spectrum techniques, together with low power and low data rate transmissions.

Antonio, Franklin P.; Gilhousen, Klein S.; Jacobs, Irwin M.; Weaver, Linday A., Jr.

1988-01-01

353

Are some people sensitive to mobile phone signals? Within participants double blind randomised provocation study  

PubMed Central

Objective To test whether people who report being sensitive to mobile phone signals have more symptoms when exposed to a pulsing mobile signal than when exposed to a sham signal or a non-pulsing signal. Design Double blind, randomised, within participants provocation study. Setting Dedicated suite of offices at King's College London, between September 2003 and June 2005. Participants 60 “sensitive” people who reported often getting headache-like symptoms within 20 minutes of using a global system for mobile communication (GSM) mobile phone and 60 “control” participants who did not report any such symptoms. Intervention Participants were exposed to three conditions: a 900 MHz GSM mobile phone signal, a non-pulsing carrier wave signal, and a sham condition with no signal present. Each exposure lasted for 50 minutes. Main outcome measures The principal outcome measure was headache severity assessed with a 0-100 visual analogue scale. Other outcomes included six other subjective symptoms and participants' ability to judge whether a signal was present. Results Headache severity increased during exposure and decreased immediately afterwards. However, no strong evidence was found of any difference between the conditions in terms of symptom severity. Nor did evidence of any differential effect of condition between the two groups exist. The proportion of sensitive participants who believed a signal was present during GSM exposure (60%) was similar to the proportion who believed one was present during sham exposure (63%). Conclusions No evidence was found to indicate that people with self reported sensitivity to mobile phone signals are able to detect such signals or that they react to them with increased symptom severity. As sham exposure was sufficient to trigger severe symptoms in some participants, psychological factors may have an important role in causing this condition. Trial registration ISRCTN81432775. PMID:16520326

Rubin, G James; Hahn, Gareth; Everitt, Brian S; Cleare, Anthony J; Wessely, Simon

2006-01-01

354

A Secure System for Data Collection in GSM Networks  

Microsoft Academic Search

Summary This article is focused on the design and realization of secure long-line data connection in GSM network. The developing module Motorola MPC860 was used in this solution. This module is based on the operating system Linux. This operating system became the basis for the script development in the realization of automated long- line measuring system in GSM networks. The

Martin Koutny; Jiri Misurec; Petr Mlynek

355

Is communication competence still good for interpersonal media?: Mobile phone and instant messenger  

Microsoft Academic Search

The concept of communication competence has developed in the area of nonmediated interpersonal communication. With the advent of digital media, interpersonal communication has been heavily dependent on interpersonal media. The sharp distinction between theories for nonmediated communication and mediated communication is disappearing. The interconnectedness of face-to-face communication and mediated interpersonal communication is a salient current phenomenon. To explore the relation

Yoosun Hwang

2011-01-01

356

A Provably-Correct Protocol for Seamless Communication with Mobile, Multi-Homed Hosts  

E-print Network

Modern consumer devices, like smartphones and tablets, have multiple interfaces (e.g., WiFi and 3G) that attach to new access points as users move. These mobile, multi-homed computers are a poor match with an Internet architecture that binds connections to fixed end-points with topology- dependent addresses. As a result, hosts typically cannot spread a connection over multiple interfaces or paths, or change locations without breaking existing connections. In this paper, we introduce ECCP, an end-host connection control protocol that allows hosts to communicate over mul- tiple interfaces with dynamically-changing IP addresses. Each ECCP connection consists of one or more flows, each associated with an interface or path. A host can move an existing flow from one interface to another or change the IP address using in-band signaling, without any support from the underlying network. We use formal models to verify that ECCP works correctly in the presence of packet loss, out-of-order delivery, and frequent mobility...

Arye, Matvey; Kiefer, Robert; Rexford, Jennifer; Freedman, Michael J

2012-01-01

357

Topics in circuits for communications - Integrated circuits for channel coding in 3g cellular mobile wireless systems  

Microsoft Academic Search

Error control coding is a key element of any digital wireless communication system, minimizing the effects of noise and interference on the transmitted signal at the physical layer. In 3G mobile cellular wireless systems, error control coding must accommodate both voice and data users, whose requirements vary considerably in terms of latency, throughput, and the impact of errors on the

Charles Thomas; Mark A. Bickerstaff; Linda M. Davis; Thomas Prokop; Ben Widdup; Gongyu Zhou; D. Garrett; C. Nicol

2003-01-01

358

Abstract--Securing multicast communications in Mobile Ad Hoc Networks (MANET) is considered among the most challenging  

E-print Network

Abstract--Securing multicast communications in Mobile Ad Hoc Networks (MANET) is considered among the most challenging research directions in the areas of wireless networking and security. MANET for these applications. However, the limitations of the dynamic, infrastructure-less nature of MANET impose major

Baras, John S.

359

The Complexity of Social Mobilization in Health Communication: Top-Down and Bottom-Up Experiences in Polio Eradication  

Microsoft Academic Search

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

Rafael Obregón; Silvio Waisbord

2010-01-01

360

Measured path loss and multipath propagation characteristics in UHF and microwave frequency bands for urban mobile communications  

Microsoft Academic Search

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

Yasuhiro Oda; Reiko Tsuchihashi; Kouichi Tsunekawa; Masaharu Hata

2001-01-01

361

Satellite applications to electric-utility communications needs. [land mobile satellite service  

NASA Technical Reports Server (NTRS)

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.

Horstein, M.; Barnett, R.

1981-01-01

362

7 CFR 1488.22 - Communications.  

Code of Federal Regulations, 2011 CFR

...COMMODITIES Financing of Export Sales of Agricultural Commodities From Private Stocks Under CCC Export Credit Sales Program (GSM-5) Miscellaneous Provisions § 1488.22 Communications. (a) Unless otherwise provided, written...

2011-01-01

363

7 CFR 1488.22 - Communications.  

Code of Federal Regulations, 2010 CFR

...COMMODITIES Financing of Export Sales of Agricultural Commodities From Private Stocks Under CCC Export Credit Sales Program (GSM-5) Miscellaneous Provisions § 1488.22 Communications. (a) Unless otherwise provided, written...

2010-01-01

364

The role of interpersonal communication in the process of knowledge mobilization within a community-based organization: a network analysis  

PubMed Central

Background Diffusion of innovations theory has been widely used to explain knowledge mobilization of research findings. This theory posits that individuals who are more interpersonally connected within an organization may be more likely to adopt an innovation (e.g., research evidence) than individuals who are less interconnected. Research examining this tenet of diffusion of innovations theory in the knowledge mobilization literature is limited. The purpose of the present study was to use network analysis to examine the role of interpersonal communication in the adoption and mobilization of the physical activity guidelines for people with spinal cord injury (SCI) among staff in a community-based organization (CBO). Methods The study used a cross-sectional, whole-network design. In total, 56 staff completed the network survey. Adoption of the guidelines was assessed using Rogers’ innovation-decision process and interpersonal communication was assessed using an online network instrument. Results The patterns of densities observed within the network were indicative of a core-periphery structure revealing that interpersonal communication was greater within the core than between the core and periphery and within the periphery. Membership in the core, as opposed to membership in the periphery, was associated with greater knowledge of the evidence-based physical activity resources available and engagement in physical activity promotion behaviours (ps?communication is associated with knowledge mobilization and highlight how the network structure could be improved for further dissemination efforts. Keywords: diffusion of innovations; network analysis; community-based organization; knowledge mobilization; knowledge translation, interpersonal communication. PMID:24886429

2014-01-01

365

Printed Monopole Slot Antenna for Internal Multiband Mobile Phone Antenna  

Microsoft Academic Search

A new internal multiband mobile phone antenna formed by two printed monopole slots of different lengths cut at the edge of the system ground plane of the mobile phone is presented. The antenna can generate two wide bands centered at about 900 and 2100 MHz to cover the GSM850\\/GSM900\\/DCS\\/PCS\\/UMTS bands and the 2.4-GHz WLAN band. Further, the antenna has a

Chun-I. Lin; Kin-Lu Wong

2007-01-01

366

An internal dual-band mobile phone antenna  

Microsoft Academic Search

An internal dual-band mobile phone antenna designed to operate at GSM900 and GSM1800 bands is presented. The antenna is derived from a quarter-wave planar inverted F-type antenna, which has at this state proved to be the most promising candidate for mobile applications due to its compact size and good performance. The FDTD method is used in the study and an

S. Tarvas; A. Isohatala

2000-01-01

367

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)

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.

Wilcox, R. E.

1985-01-01

368

Single antenna interference cancellation in asynchronous GSM/GPRS networks  

E-print Network

In this project, we have proposed a decorrelator-based single antenna interference cancellation algorithm for the asynchronous GSM/GPRS network. The algorithm is tested according to the current SAIC/DARP performance ...

Chan, Chung, Ph. D. Massachusetts Institute of Technology

2005-01-01

369

Low-mobility channel tracking for MIMO-OFDM communication systems  

NASA Astrophysics Data System (ADS)

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.

Pagadarai, Srikanth; Wyglinski, Alexander M.; Anderson, Christopher R.

2013-12-01

370

Analysis and design of a multi-transceiver optical cylinder antenna for mobile free space optical communication  

NASA Astrophysics Data System (ADS)

Due to the notable influence of atmospheric effects and the objects relative motion, acquisition, pointing and tracking (APT) are the key technologies to establish the communication link in free space optical communication (FSO). In this paper, an all-direction, cylinder-shaped optical antenna is proposed, and the theory and method of beam control are mainly studied. On condition that the communication terminals move randomly and the antenna self-rotates in constant or variable velocity, numerical simulations are carried out. In detail, some significant parameters in practice are analyzed, like the communication time, actual bandwidth and interrupted time, and compared with theoretical results. The consequence shows that the beam control method is feasible, and this optical antenna can meet the demands of fast mobile FSO in a certain range of height.

Shang, Tao; Jia, Jijun; Wang, Xin

2012-11-01

371

Requirements for a mobile communications satellite system. Volume 3: Large space structures measurements study  

NASA Technical Reports Server (NTRS)

This study report defines a set of tests and measurements required to characterize the performance of a Large Space System (LSS), and to scale this data to other LSS satellites. Requirements from the Mobile Communication Satellite (MSAT) configurations derived in the parent study were used. MSAT utilizes a large, mesh deployable antenna, and encompasses a significant range of LSS technology issues in the areas of structural/dynamics, control, and performance predictability. In this study, performance requirements were developed for the antenna. Special emphasis was placed on antenna surface accuracy, and pointing stability. Instrumentation and measurement systems, applicable to LSS, were selected from existing or on-going technology developments. Laser ranging and angulation systems, presently in breadboard status, form the backbone of the measurements. Following this, a set of ground, STS, and GEO-operational were investigated. A third scale (15 meter) antenna system as selected for ground characterization followed by STS flight technology development. This selection ensures analytical scaling from ground-to-orbit, and size scaling. Other benefits are cost and ability to perform reasonable ground tests. Detail costing of the various tests and measurement systems were derived and are included in the report.

Akle, W.

1983-01-01

372

Adaptive MIMO-MLSE Blind Detection in Heterogeneous Stream Transmission for Mobile Radio Communications  

NASA Astrophysics Data System (ADS)

This paper proposes a novel MIMO system that introduces a heterogeneous stream (HTS) scheme and a blind signal detection method for mobile radio communications. The HTS scheme utilizes different modulation or coding methods for different MIMO streams, and the blind detection method requires no training sequences for signal separation, detection, and channel estimation. The HTS scheme can remove the ambiguity in identifying separated streams without unique words that are necessary in conventional MIMO blind detection. More specifically, two examples of HTS are considered: modulation type HTS (MHTS) and timing-offset type HTS (THTS). MHTS, which utilizes different modulation constellations with the same bandwidth for different streams, has been previously investigated. This paper proposes THTS which utilizes different transmission timing with the same modulation. THTS can make the blind detection more robust and effective with fractional sampling. The blind joint processing of detection and channel estimation performs adaptive blind MIMO-MLSE and is derived from an adaptive blind MLSE equalizer that employs the recursive channel estimation with the Moore-Penrose generalized inverse. Computer simulations show that the proposed system can achieve superior BER performance with Eb/N0 degradation of 1dB in THTS and 2.5dB in MHTS compared with the ideal maximum likelihood detection.

Kanno, Issei; Suzuki, Hiroshi; Fukawa, Kazuhiko

373

A new coherent demodulation technique for land-mobile satellite communications  

NASA Technical Reports Server (NTRS)

An advanced coherent demodulation technique is described for land mobile satellite (LMS) communications. The proposed technique features a combined narrow/wind band dual open loop carrier phase estimator, which is effectively able to compensate the fast carrier phase fluctuation by fading with sacrificing a phase slip rate. Also included is the realization of quick carrier and clock reacquisition after shadowing by taking open loop structure. Its bit error rate (BER) performance is superior to that of existing detection schemes, showing a BER of 1 x 10(exp -2) at 6.3 dB E sub b/N sub o over the Rician channel with 10 dB C/M and 200 Hz (1/16 modulation rate) fading pitch f sub d for QPSK. The proposed scheme consists of a fast response carrier recovery and a quick bit timing recovery with an interpolation. An experimental terminal model was developed to evaluate its performance at fading conditions. The results are quite satisfactory, giving prospects for future LMS applications.

Yoshida, Shousei; Tomita, Hideho

1990-01-01

374

Energy consumption in mobile phones: a measurement study and implications for network applications  

Microsoft Academic Search

In this paper, we present a measurement study of the energy con- sumption characteristics of three widespread mobile networking technologies: 3G, GSM, and WiFi. We find that 3G and GSM in- cur a high tail energy overhead because of lingering in high power states after completing a transfer. Based on these measurements, we develop a model for the energy consumed

Niranjan Balasubramanian; Aruna Balasubramanian; Arun Venkataramani

2009-01-01

375

Compact, low profile antennas for MSAT and mini-M and Std-M land mobile satellite communications  

NASA Technical Reports Server (NTRS)

CAL Corporation has developed a new class of low profile radiating elements for use in planar phased array antennas. These new elements have been used in the design of a low cost, compact, low profile antenna unit for MSAT and INMARSAT Mini-M land mobile satellite communications. The antenna unit which measures roughly 32 cm in diameter by 5 cm deep incorporates a compact LNA and diplexer unit as well as a complete, low cost, beam steering system. CAL has also developed a low profile antenna unit for INMARSAT-M land mobile satellite communications. A number of these units, which utilize a microstrip patch array design, were put into service in 1994.

Strickland, P. C.

1995-01-01

376

Communication.  

ERIC Educational Resources Information Center

The following essays on communication are presented: communication as a condition of survival, communication for special purposes, the means of transmission of communication, communication within social and economic structures, the teaching of communication through the press, the teaching of modern languages, communication as a point of departure,…

Strauss, Andre

377

A comparison study of the uplink performance of W-CDMA and OFDM for mobile multimedia communications via LEO satellites  

Microsoft Academic Search

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

A. Papathanassiou; A. K. Salkintzis; P. T. Mathiopoulos

2001-01-01

378

Abstract In this position paper, we present our research work focused on the design of a communication architecture  

E-print Network

of a communication architecture to access TCP/IP networks (mainly Internet) through GSM. We exploit the existing and widely used TCP/IP communication architecture, but also take into account the specific features of wireless links and GSM networks. Our proposal is based in the indirect model of client/server interaction

Miguel-Alonso, José

379

GSM 900 MHz radiation inhibits ants' association between food sites and encountered cues.  

PubMed

The kinetics of the acquisition and loss of the use of olfactory and visual cues were previously obtained in six experimental colonies of the ant Myrmica sabuleti meinert 1861, under normal conditions. In the present work, the same experiments were conducted on six other naive identical colonies of M. sabuleti, under electromagnetic radiation similar to those surrounding GSM and communication masts. In this situation, no association between food and either olfactory or visual cues occurred. After a recovery period, the ants were able to make such an association but never reached the expected score. Such ants having acquired a weaker olfactory or visual score and still undergoing olfactory or visual training were again submitted to electromagnetic waves. Not only did they lose all that they had memorized, but also they lost it in a few hours instead of in a few days (as under normal conditions when no longer trained). They kept no visual memory at all (instead of keeping 10% of it as they normally do). The impact of GSM 900 MHz radiation was greater on the visual memory than on the olfactory one. These communication waves may have such a disastrous impact on a wide range of insects using olfactory and/or visual memory, i.e., on bees. PMID:22268919

Cammaerts, Marie-Claire; De Doncker, Philippe; Patris, Xavier; Bellens, François; Rachidi, Zoheir; Cammaerts, David

2012-06-01

380

Satellite-aided mobile radio concepts study: Concept definition of a satellite-aided mobile and personal radio communication system  

Microsoft Academic Search

The satellite system requires the use of a large satellite antenna and spacecraft array power of about 12 kW or more depending on the operating frequency. Technology developments needed include large offset reflector multibeam antennas, satellite electrical power sybsystems providing greater than 12 kW of power, signal switching hardware, and linearized efficient solid state amplifiers for the satellite-aided mobile band.

R. E. Anderson

1979-01-01

381

Adaptive combination of cancelling co-channel interference and decoding of error-correcting codes for DS-SS CDMA mobile communication system  

Microsoft Academic Search

This paper introduces an adaptive cascaded combination of cancelling co-channel interference (CCI) and decoding of error-correcting codes for a DS-SS CDMA mobile communication system. The analysis of a previous study by Shaheen and Gupta (see IEEE IPCCC Proceedings, Phoenix, Arizona, March 1995) indicated that conventional CCI cancellation techniques might not be as effective, especially for heavily loaded mobile communication systems.

K. M. Shaheen; Someshwar C. Gupta

1995-01-01

382

1800 MHz in vitro exposure device for experimental studies on the effects of mobile communication systems.  

PubMed

A wire patch cell (WPC) operating at the uplink frequency band of GSM 1800 MHz has been designed for in vitro experiments with the aim of investigating the possible biological effects of electromagnetic radiation associated with cellular phones. The 1800 MHz WPC design is a direct descendant of the original 900 MHz WPC introduced by Laval et al. This system provides a homogeneous specific absorption rate distribution, using four 3.5 cm petri dishes simultaneously. Numerical dosimetry has been performed using a commercial code (CST Microwave Studio), in order to evaluate accurately the efficiency of the structure (in terms of W kg(-1) per 1 W input power) and the distribution in the chosen biological target. The numerical results have been confirmed by experimental measurements performed by measuring thermal increase due to a high power impulse. The efficiency of the structure is 1.25 +/- 25% W kg(-1) per 1 W input power higher than the efficiency of the 900 MHz WPC. A few adjustments have been made in order to use the WPC in a standard incubator and to avoid thermal increases related to the radio frequency exposure. This exposure system has been adopted for the experiments scheduled in the RAMP and GUARD projects (VFPE). PMID:15494360

Ardoino, L; Lopresto, V; Mancini, S; Pinto, R; Lovisolo, G A

2004-01-01

383

Secure Group Communication for Mobile P2P Groups: A Survey  

Microsoft Academic Search

Abstract This report presents an overview over secure group communication paradigms in ad hoc networks, with especial attention to join and leave algorithms. Although classical group communication, after more than 25 years of development, is by now well understood and formalized, group communication for ad hoc networks is still under development. Firstly, the paradigm of groups in distributed computing is

Zinaida Benenson

384

A Mobile Ad-Hoc Network Data Communication Benchmark Leslie D. Fife  

E-print Network

protocols proposed is the lack of a standard test environment or benchmark. A MANET data communication and demonstrates the benchmark through analysis and simulation of the TriM MANET data communication protocol. While conducting research in MANET data communication, it became apparent that a standard benchmark

Gruenwald, Le

385

A One-Pass Heuristic for Cooperative Communication in Mobile Ad Hoc Networks  

Microsoft Academic Search

Ad hoc networks have been used in the last few years to provide communications means among agents that need to accomplish common goals. Due to the importance of communication for the success of such missions, we study the problem of maximizing communication among a set of agents. As a practical tool to solve such problems, we introduce a one-pass randomized

CLAYTON W. COMMANDER; CARLOS A. S. OLIVEIRA; Panos Pardalos; Mauricio Resende

386

A proposed architecture for a satellite-based mobile communications network - The lowest three layers  

NASA Technical Reports Server (NTRS)

Architecture for a commercial mobile satellite network is proposed. The mobile satellite system (MSS) is composed of a network management center, mobile terminals, base stations, and gateways; the functions of each component are described. The satellite is a 'bent pipe' that performs frequency translations, and it has multiple UHF beams. The development of the MSS design based on the seven-layer open system interconnection model is examined. Consideration is given to the functions of the physical, data link, and network layers and the integrated adaptive mobile access protocol.

Yan, T. Y.; Naderi, F. M.

1986-01-01

387

A Survey of Automated GSM Based Irrigation Systems  

E-print Network

Abstract — Irrigation is the process of artificially supplying water to land where crops are cultivated. Traditionally hand pumps, canal water and rainfall were a major source of water supply for irrigation. This method has led to severe drawbacks like under irrigation, over-irrigation which in turn causes leaching and loss of nutrient content of soil. Changing environmental conditions and shortage of water have led to the need for a system which efficiently manages irrigation of fields. Automated irrigation system is a machine based system, which automates the irrigation of land by combining various software and hardware approaches together for field irrigation. This paper deals with a detailed survey of various GSM based automated farm irrigation systems. GSM serves as an important part since it is responsible for controlling the irrigation facility and sends them to receiver through coded signal. Our study is concentrated on comparison of various GSM approaches.

Rika Ch; Surbhi Agarwal; Er. B. Persis; Urbana Ivy

388

Initial experience with a handheld device digital imaging and communications in medicine viewer: OsiriX mobile on the iPhone.  

PubMed

Medical imaging is commonly used to diagnose many emergent conditions, as well as plan treatment. Digital images can be reviewed on almost any computing platform. Modern mobile phones and handheld devices are portable computing platforms with robust software programming interfaces, powerful processors, and high-resolution displays. OsiriX mobile, a new Digital Imaging and Communications in Medicine viewing program, is available for the iPhone/iPod touch platform. This raises the possibility of mobile review of diagnostic medical images to expedite diagnosis and treatment planning using a commercial off the shelf solution, facilitating communication among radiologists and referring clinicians. PMID:20567992

Choudhri, Asim F; Radvany, Martin G

2011-04-01

389

Manufacturing consent?: Media messages in the mobilization against HIV/AIDS in India and lessons for health communication.  

PubMed

Despite repeated calls for a more critical and "culture-centered" approach to health communication, textual analysis of televised public service advertising (PSA) campaigns has been largely neglected, even by critical communication scholars. In the case of "developing" countries in particular, there is an acute shortage of such literature. On the other hand, following the outbreak of major public health diseases such as AIDS, most countries have adopted PSA campaigns as the most preferred means of communicating messages. Drawing on insights from cultural studies (especially Antonio Gramsci and Stuart Hall), this article engages in textual analysis of the televised PSA campaigns launched by the Indian state to prevent HIV/AIDS between 2002 and 2005. Through such analysis, it argues that although few diseases in Indian history have spurred such massive and creative efforts for mass mobilization as AIDS, these efforts, in terms of their ethical implications, have been far from emancipatory. In fact, they have constructed and perpetuated the logic of domination and control along class, gender, sexuality, and knowledge systems, often contradicting and potentially harming the very goal of HIV prevention and of health promotion and empowerment. This article also holds that assessing public health campaigns through textual analysis, a highly neglected tool in health communication, can shed important light on a far more complex and changing nature of the state and public policy, especially in the developing world, thereby opening up space for alternative theorizing for health communication and social change. PMID:23631645

Khan, Shamshad

2014-01-01

390

DISTORTION-CLASS WEIGHTED ACOUSTIC MODELING FOR ROBUST SPEECH RECOGNITION UNDER GSM RPE-LTP CODING  

E-print Network

DISTORTION-CLASS WEIGHTED ACOUSTIC MODELING FOR ROBUST SPEECH RECOGNITION UNDER GSM RPE-LTP CODING-rate GSM RPE-LTP coding by combining two sets of acoustic models during recognition, one set trained on GSM distortion to the quantized long-term residual introduced by the RPE-LTP codec and discuss how

Stern, Richard

391

Hybrid GPS-GSM Localization of Automobile Tracking System  

E-print Network

An integrated GPS-GSM system is proposed to track vehicles using Google Earth application. The remote module has a GPS mounted on the moving vehicle to identify its current position, and to be transferred by GSM with other parameters acquired by the automobile's data port as an SMS to a recipient station. The received GPS coordinates are filtered using a Kalman filter to enhance the accuracy of measured position. After data processing, Google Earth application is used to view the current location and status of each vehicle. This goal of this system is to manage fleet, police automobiles distribution and car theft cautions.

Al-Khedher, Mohammad A

2012-01-01

392

A medical application integrating remote 3D visualization tools to access picture archiving and communication system on mobile devices.  

PubMed

With computing capability and display size growing, the mobile device has been used as a tool to help clinicians view patient information and medical images anywhere and anytime. However, for direct interactive 3D visualization, which plays an important role in radiological diagnosis, the mobile device cannot provide a satisfactory quality of experience for radiologists. This paper developed a medical system that can get medical images from the picture archiving and communication system on the mobile device over the wireless network. In the proposed application, the mobile device got patient information and medical images through a proxy server connecting to the PACS server. Meanwhile, the proxy server integrated a range of 3D visualization techniques, including maximum intensity projection, multi-planar reconstruction and direct volume rendering, to providing shape, brightness, depth and location information generated from the original sectional images for radiologists. Furthermore, an algorithm that changes remote render parameters automatically to adapt to the network status was employed to improve the quality of experience. Finally, performance issues regarding the remote 3D visualization of the medical images over the wireless network of the proposed application were also discussed. The results demonstrated that this proposed medical application could provide a smooth interactive experience in the WLAN and 3G networks. PMID:24705800

He, Longjun; Ming, Xing; Liu, Qian

2014-04-01

393

Control of an indoor autonomous mobile communications relay via antenna diversity  

NASA Astrophysics Data System (ADS)

Presented here is a motion planning scheme for enabling a quadrotor to serve as an autonomous communications relay in indoor/GPS-denied environments. Using antenna selection diversity, the quadrotor is able to optimize its location in the communication chain so as to maximize the link throughput. Measurements of the communications field drive a gradient descent algorithm that moves the quadrotor to an optimal location while avoiding obstacles, all without the use of positioning data.

Griffin, Brian; Fierro, Rafael; Palunko, Ivana

2010-04-01

394

Mobile Website Overview Mobile Application Development Policy  

E-print Network

of University Communication May 29, 2012 #12;Mobile Web/Mobile App Development Policy Villanova University May .......................................................................................................................... 12 #12;Mobile Web/Mobile App Development Policy Villanova University May 29, 2012 Page 3 of 13 I accesses the mobile web. Native apps, in contrast, are permanently downloaded to mobile devices and must

Jackman, Todd

395

WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 2013; 13:12631280  

E-print Network

is powered by petrol or electricity, its maximum travel distance per tour is bounded. The mobile sink in wireless sen- sor networks assumed that there is a fixed base station (sink). The sensed data is relayed

Liang, Weifa

396

Relationships between Emotional States and Emoticons in Mobile Phone Email Communication in Japan  

ERIC Educational Resources Information Center

Three related studies conducted on the role of emotional transfer in email messages were studied in order to better understand Japanese college students' online communications and their broader participation in online communications. The first study investigated users' initiatives in preventing emotional misunderstandings when sending email.…

Kato, Shogo; Kato, Yuuki; Scott, Douglass

2009-01-01

397

Information\\/communication and dispatching strategies for networks with mobile servers  

Microsoft Academic Search

The dispatch problem for a network with a general number of nonstationary service units is discussed. The possibility of dispatching a service unit to a call for service while the unit is in motion depends on the quality of the information\\/communication system available. Three information\\/communication systems are investigated: two extreme cases in which only stationary units can be dispatched from

O. Berman; M. R. Rahnama

1990-01-01

398

Relationships between Emotional States and Emoticons in Mobile Phone Email Communication in Japan  

Microsoft Academic Search

Three related studies conducted on the role of emotional transfer in email messages were studied in order to better understand Japanese college students' online communications and their broader participation in online communications. The first study investigated users' initiatives in preventing emotional misunderstandings when sending email. Results showed message writers used emoticons as \\

Shogo Kato; Yuuki Kato; Douglass Scott

2009-01-01

399

Effects of mobile phone radiation on reproduction and development in Drosophila melanogaster  

Microsoft Academic Search

In this report we examined the effects of a discontinuous radio frequency (RF) signal produced by a GSM multiband mobile phone (900\\/1,900 MHz; SAR ? 1.4 W\\/kg) on Drosophila melanogaster, during the 10-day developmentalperiodfromegglayingthroughpupation. Asfoundearlierwithlowfrequencyexposures,thenon-thermal radiation from the GSM mobile phone increased numbers of offspring, elevated hsp70 levels, increased serum response element (SRE) DNA-binding and induced the phosphorylation of the

David Weisbrot; Hana Lin; Lin Ye; Martin Blank; Reba Goodman

2003-01-01

400

Modular, Cost-Effective, Extensible Avionics Architecture for Secure, Mobile Communications  

NASA Technical Reports Server (NTRS)

Current onboard communication architectures are based upon an all-in-one communications management unit. This unit and associated radio systems has regularly been designed as a one-off, proprietary system. As such, it lacks flexibility and cannot adapt easily to new technology, new communication protocols, and new communication links. This paper describes the current avionics communication architecture and provides a historical perspective of the evolution of this system. A new onboard architecture is proposed that allows full use of commercial-off-the-shelf technologies to be integrated in a modular approach thereby enabling a flexible, cost-effective and fully deployable design that can take advantage of ongoing advances in the computer, cryptography, and telecommunications industries.

Ivancic, William D.

2006-01-01

401

Modular, Cost-Effective, Extensible Avionics Architecture for Secure, Mobile Communications  

NASA Technical Reports Server (NTRS)

Current onboard communication architectures are based upon an all-in-one communications management unit. This unit and associated radio systems has regularly been designed as a one-off, proprietary system. As such, it lacks flexibility and cannot adapt easily to new technology, new communication protocols, and new communication links. This paper describes the current avionics communication architecture and provides a historical perspective of the evolution of this system. A new onboard architecture is proposed that allows full use of commercial-off-the-shelf technologies to be integrated in a modular approach thereby enabling a flexible, cost-effective and fully deployable design that can take advantage of ongoing advances in the computer, cryptography, and telecommunications industries.

Ivancic, William D.

2007-01-01

402

SMALL-BANDWIDTH INTEGRATED TUNABLE BANDPASS FILTERS FOR GSM APPLICATIONS  

E-print Network

loss of 4.0 dB. The filter is fabricated using a combination of thick high aspect-ratio silver platingSMALL-BANDWIDTH INTEGRATED TUNABLE BANDPASS FILTERS FOR GSM APPLICATIONS M. Rais-Zadeh and F. Ayazi lumped- element filter at 831 MHz with a 3dB-bandwidth of 77 MHz (9% bandwidth) and an embedded insertion

Ayazi, Farrokh

403

Link Layer Enhancements for TCP\\/IP over GSM  

Microsoft Academic Search

This paper has two main contributions. First the ex- tremely high latency of the GSM link is revealed which through measurements is determined to have a magnitude usually only known from satellite links. This greatly impacts the link configu- ration time of packet framing protocols for serial links like the Point-to-Point Protocol (PPP). The key idea of the proposed solu-

Reiner Ludwig; Bela Rathonyi

1999-01-01

404

Do GSM 900MHz signals affect cerebral blood circulation? A near-infrared spectrophotometry study  

NASA Astrophysics Data System (ADS)

Effects of GSM 900MHz signals (EMF) typical for a handheld mobile phone on the cerebral blood circulation were investigated using near-infrared spectrophotometry (NIRS) in a three armed (12W/kg, 1.2W/kg, sham), double blind, randomized crossover trial in 16 healthy volunteers. During exposure we observed borderline significant short term responses of oxyhemoglobin and deoxyhemoglobin concentration, which correspond to a decrease of cerebral blood flow and volume and were smaller than regular physiological changes. Due to the relatively high number of statistical tests, these responses may be spurious and require further studies. There was no detectable dose-response relation or long term response within 20min. The detection limit was a fraction of the regular physiological changes elicited by functional activation. Compared to previous studies using PET, NIRS provides a much higher time resolution, which allowed investigating the short term effects efficiently, noninvasively, without the use of radioactive tracers and with high sensitivity.

Wolf, Martin; Haensse, Daniel; Morren, Geert; Froehlich, Juerg

2006-06-01

405

A matrix-form GSM-CFD solver for incompressible fluids and its application to hemodynamics  

NASA Astrophysics Data System (ADS)

A GSM-CFD solver for incompressible flows is developed based on the gradient smoothing method (GSM). A matrix-form algorithm and corresponding data structure for GSM are devised to efficiently approximate the spatial gradients of field variables using the gradient smoothing operation. The calculated gradient values on various test fields show that the proposed GSM is capable of exactly reproducing linear field and of second order accuracy on all kinds of meshes. It is found that the GSM is much more robust to mesh deformation and therefore more suitable for problems with complicated geometries. Integrated with the artificial compressibility approach, the GSM is extended to solve the incompressible flows. As an example, the flow simulation of carotid bifurcation is carried out to show the effectiveness of the proposed GSM-CFD solver. The blood is modeled as incompressible Newtonian fluid and the vessel is treated as rigid wall in this paper.

Yao, Jianyao; Liu, G. R.

2014-10-01

406

Mobility Prediction Progressive Routing (MP2R), a Cross-Layer Design for Inter-Vehicle Communication  

NASA Astrophysics Data System (ADS)

In this paper we analyze the characteristics of vehicle mobility and propose a novel Mobility Prediction Progressive Routing (MP2R) protocol for Inter-Vehicle Communication (IVC) that is based on crosslayer design. MP2R utilizes the additional gain provided by the directional antennas to improve link quality and connectivity; interference is reduced by the directional transmission. Each node learns its own position and speed and that of other nodes, and performs position prediction. (i) With the predicted progress and link quality, the forwarding decision of a packet is locally made, just before the packet is actually transmitted. In addition the load at the forwarder is considered in order to avoid congestion. (ii) The predicted geographic direction is used to control the beam of the directional antenna. The proposed MP2R protocol is especially suitable for forwarding burst traffic in highly mobile environments. Simulation results show that MP2R effectively reduces Packet Error Ratio (PER) compared with both topology-based routing (AODV [1], FSR [2]) and normal progressive routing (NADV [18]) in the IVC scenarios.

Tang, Suhua; Kadowaki, Naoto; Obana, Sadao

407

Opening communication channels with people living with HIV using mobile phone text messaging: insights from the CAMPS trial  

PubMed Central

Background Using two-way mobile phone text messages to improve adherence to antiretroviral medication enhances communication between patients and health workers. We describe the implications of participants’ responses to text messages in the Cameroon Mobile Phone SMS (CAMPS) trial. Findings This is a cross-sectional analysis of data from the intervention arm of the CAMPS trial. CAMPS was a randomized controlled trial of motivational text messaging versus usual care to improve adherence to antiretroviral medication among people living with HIV in Yaounde, Cameroon (n?=?200) over a 6 month period. Participants in the intervention arm (n?=?101) were given a contact phone number, but were not required to respond to their reminder messages. If they did, their responses were noted and reported as counts and percentages. We received 99 phone calls and 55 text messages (154 responses) from 48 participants during the study period. The median number of responses was 1 (first quartile [Q1]: 1; third quartile [Q3]: 3). Half (n?=?79, 51.1%) of them were expressions of gratitude. The rest included requests for logistical (n?=?21, 13.6%), medical (n?=?20, 12.9%) and financial (n?=?11, 7.1%) support. Conclusion Initiating two-way mobile communication opens more channels for people living with HIV to express unmet needs. Researchers, policy makers and clinicians should be ready to respond to the needs expressed by patients who respond to text messages. Trial registration Pan-African Clinical Trials Registry: PACTR201011000261458; Clinicaltrials.gov: NCT01247181 PMID:23557081

2013-01-01

408

FlickerThis : a mobile service to facilitate grounding in communication through viewable media content  

E-print Network

Remote communication has become part of our daily lives. Technology plays a decisive role in filling the gap caused by discrepancies in time and space between us and the people we want to reach. However, the level of ...

Lin, Dori Tung-Yun

2009-01-01

409

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

E-print Network

followed up by an extensive online questionnaire distributed to all Agricultural Communications and Journalism majors and minors at Texas A&M University in order to collect quantitative data concerning smart device ownership percentages, usage ratios...

Meadows, Casey

2013-02-12

410

Communications  

NASA Technical Reports Server (NTRS)

Communication in its many forms is a critical component for an effective Space Grant Program. Good communication is needed within individual Space Grant College/Consortia, for example between consortium affiliates and the consortium program office. Effective communication between the several programs, NASA Headquarters, and NASA field centers also is required. Further, communication among the above program elements, industry, local and state government, and the public also are necessary for meeting program objectives.

Stouffer, Donald D.

1990-01-01

411

Adaptive Resource Allocation for Statistical QoS Provisioning in Mobile Wireless Communications and Networks  

E-print Network

problems for mobile multicast with diverse QoS requirements, we further integrate the statistical delay-QoS control techniques — effective capacity theory, statistical loss-rate control, and information theory to propose a QoS-driven optimization framework...

Du, Qinghe

2012-02-14

412

Divergent Perspectives on Language-Discordant Mobile Medical Professionals' Communication with Colleagues: An Exploratory Study  

ERIC Educational Resources Information Center

Little is known about how language-discordant mobile medical professionals (MMPs), defined as doctors who work in foreign countries, cultures, and languages, interact with their colleagues. The number of MMPs around the world is growing, and their interactions with colleagues have direct consequences for both patients' health and their own…

Gasiorek, Jessica; van de Poel, Kris

2012-01-01

413

76 FR 80402 - Certain Personal Data and Mobile Communications Devices and Related Software; Final Determination...  

Federal Register 2010, 2011, 2012, 2013

...demonstrated that any of the asserted patent claims were invalid. The ALJ...regarding each of the four patents asserted in this investigation...for Competitive Technology; Google Inc.; and T-Mobile USA...claims 1 and 8 of the '647 patent. The Commission has...

2011-12-23

414

Radio propagation measurements at microwave frequencies for microcellular mobile and personal communications  

Microsoft Academic Search

The design and results of a propagation experiment at 900 MHz and 11 GHz to characterize microcell channels at two distinct frequencies in various environments, from rural to dense urban, are presented. The measurements were made by transmitting a continuous-wave (CW) signal from a mobile source to a fixed base and recording the signal envelope variations as a function of

N. Amitay; R. S. Owens; R. S. Roman

1989-01-01

415

Conveying Route Information On Mobile Devices Using Communicative Acts William A Mackaness  

E-print Network

. Specifically the form of portrayal and mix of media used will vary according to a number of key factors. The technology directly influences which navigational strategies the device can support. - Preferred navigational/worry, and irritation. Given that mobile devices support a variety of media (non-linguistic auditory acts, spoken

416

Towards music download and radio broadcast convergence in mobile communications networks  

Microsoft Academic Search

The transition from physical to digital music distribution is bound to have profound implications on the music industry. So far, most of the activity related to digital music distribution has been centred on the fixed Internet. In the meantime, mobile operators have been making significant investments in extending their network capabilities to support data services. This paper includes an analysis

Sandro Grech; Sakari Luukkainen

2005-01-01

417

Autonomous Load Balancing of Data Stream Processing and Mobile Communications in Scalable Data Distribution Systems  

E-print Network

, intelligent routing of cars, sensor networks, mobile telecommunications, logistics applications and air, such as network monitoring, traffic engi- neering systems, intelligent routing of cars in metropolitan areas condition of the routes (e.g., streets and roads) and guide their users - the drivers - towards the best

Endler, Markus

418

Communications.  

ERIC Educational Resources Information Center

This manual, prepared by a distributive education (DE) class at Delaware State College, was designed for use by DE teacher-coordinators who teach communication skills. Included are lessons, activities, and resource materials relating to the following communication skills: functional speaking, written communication, telephone etiquette, customer…

Grandfield, Raymond J., Ed.

419

A space system integrating earth observation and mobile communications for equatorial remote areas  

NASA Astrophysics Data System (ADS)

The integration of two constellations of light and low-cost satellites, the Equatorial Communications (ECO) system and a polar orbit system for World Observation and Monitoring (WOM), is proposed. The WOM involves eight satellites and portable data reception and processing equipment. Onboard data compression enables UHF transmission of earth observation data. A system for global coverage with a temporal result of two passes per day is proposed. The ECO involves eight satellites in an equatorial constellation at 2000 mm. This system can supply low-orbit communications for equatorial countries and assist in the daily monitoring of ecologically protected areas.

Ceballos, Decio C.

1993-10-01

420

Exposure of magnetic bacteria to simulated mobile phone-type RF radiation has no impact on mortality.  

PubMed

The interaction of mobile phone RF emissions with biogenic magnetite in the human brain has been proposed as a potential mechanism for mobile phone bioeffects. This is of particular interest in light of the discovery of magnetite in human brain tissue. Previous experiments using magnetite-containing bacteria exposed directly to emissions from a mobile phone have indicated that these emissions might be causing greater levels of cell death in these bacterial populations when compared to sham exposures. A repeat of these experiments examining only the radio frequency (RF) global system for mobile communication (GSM) component of the mobile phone signal in a well-defined waveguide system (REFLEX), shows no significant change in cell mortality compared to sham exposures. A nonmagnetite containing bacterial cell strain (CC-26) with similar genotype and phenotype to the magnetotactic bacteria was used as a control. These also showed no significant change in cell mortality between RF and sham exposed samples. Results indicate that the RF components of mobile phone exposure do not appear to be responsible for previous findings indicating cell mortality as a result of direct mobile phone exposure. A further mobile phone emission component that should be investigated is the 2-Hz magnetic field pulse generated by battery currents during periods of discontinuous transmission. PMID:15376948

Cranfield, Charles G; Wieser, Heinz Gregor; Dobson, Jon

2003-09-01

421

Intensity of mobile phone use and health compromising behaviours--how is information and communication technology connected to health-related lifestyle in adolescence?  

PubMed

The association of mobile phone use with health compromising behaviours (smoking, snuffing, alcohol) was studied in a survey comprising a representative sample of 14-16-year-olds (N=3485) in 2001. Mobile phone was used by 89% of respondents and by 13% for at least 1h daily. The intensity of use was positively associated with health compromising behaviours. The associations remained, although somewhat reduced, after including weekly spending money in the models. This study concludes that, at least in the present developmental level of communication technologies, intensive mobile phone use seems to be part of the same health-related lifestyle as health compromising behaviours. PMID:15683633

Leena, Koivusilta; Tomi, Lintonen; Arja, R Rimpelä

2005-02-01

422

Plants Respond to GSM-Like Radiation  

PubMed Central

In this article, we propose that an organism's general architecture is of primary importance for its ability to perceive electromagnetic radiation. Animals develop mainly as volumes for internal assimilation and appendages to increase their mobility, while plants develop as surfaces to optimize interaction with the environment. As a consequence, the proportion of cells directly interacting with EMF radiation at the organism/environment interface is much higher in plants than it is in animals, making them especially suited to study EMF effects on life. PMID:19704547

Faure, Catherine; Girard, Sebastien; Davies, Eric; Halle, Francis; Bonnet, Pierre; Ledoigt, Gerard; Paladian, Francoise

2007-01-01

423

Communication: Slow relaxation, spatial mobility gradients, and vitrification in confined films.  

PubMed

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. PMID:25362264

Mirigian, Stephen; Schweizer, Kenneth S

2014-10-28

424

System considerations, projected requirements and applications for aeronautical mobile satellite communications for air traffic services  

NASA Technical Reports Server (NTRS)

The projected application and requirements in the near term (to 1995) and far term (to 2010) for aeronautical mobile services supporting air traffic control operations are addressed. The implications of these requirements on spectrum needs, and the resulting effects on the satellite design and operation are discussed. The U.S. is working with international standards and regulatory organizations to develop the necessary aviation standards, signalling protocols, and implementation methods. In the provision of aeronautical safety services, a number of critical issues were identified, including system reliability and availability, access time, channel restoration time, interoperability, pre-emption techniques, and the system network interfaces. Means for accomplishing these critical services in the aeronautical mobile satellite service (AMSS), and the various activities relating to the future provision of aeronautical safety services are addressed.

Mcdonald, K. D.; Miller, C. M.; Scales, W. C.; Dement, D. K.

1990-01-01

425

INTERACTION OF ELECTROMAGNETIC ENERGY EMITTED BY MOBILE COMMUNICATION HANDSET WITH HUMAN HEAD  

Microsoft Academic Search

Widespread use of cell phones and other types of hand held transceivers has led to increased concern about possible health hazards, particularly about brain cancer, as the antennas for these phones lie along the head during usethe safe limit of absorption ,a theoretical evaluation is necessary.This paper deals with the simulation of interaction of e.m.energy radiated by mobile handset with

BHAROTI SINHA

426

A Software Framework for Mobile Ad hoc Data Communications Using Legacy Voice-Centric Tactical Radios  

Microsoft Academic Search

Currently, small ground units such as those operating in Iraq have very limited data communication capabilities between soldiers. Tactical chat or file transfer is available only at the battalion level or higher. To address this problem, we have developed a software application, which can leverage existing voice-centric radios to provide data services including tactical chat and file transfer capabilities to

Steven R. Brand; Geoffrey G. Xie; John H. Gibson

427

Scientific Report: Resource friendly and large scale group communication on support for mobile middleware  

Microsoft Academic Search

The research groups of EPFL and Chalmers are both activly participating in the Minema network. Previous meetings have shown that there is a good match in research interests in particular in the area of large scale group communication. The purpose of this visit was to strengthen the coorperation between the research groups on a project in the context of Minema.

Boris Koldehofe

428

PERFORMANCE CRITERIA, A SYSTEM OF COMMUNICATION FOR MOBILIZING BUILDING INDUSTRY RESOURCES.  

ERIC Educational Resources Information Center

A PROGRAM TO TEST AND DEMONSTRATE THE EFFICACY OF PERFORMANCE CRITERIA FOR UNIVERSITY BUILDING DESIGN AND CONSTRUCTION IS UNDER WAY IN NEW YORK STATE UNDER THE AUSPICES OF THE NEW YORK STATE UNIVERSITY CONSTRUCTION FUND. THE PROGRAM IS TO RESULT IN AN EXTENSIVE LIBRARY OF PERFORMANCE CRITERIA TO AID COMMUNICATION WITH ALL SECTORS OF THE BUILDING…

JACQUES, RICHARD G.

429

76 FR 75523 - Vessel Monitoring Systems; Approved Mobile Transmitting Units and Communications Service...  

Federal Register 2010, 2011, 2012, 2013

...rule, on March 1, 2012, the following MTU VMS will no longer be approved for use in Atlantic HMS fisheries: Are Trimble Galaxy 7001 and 7005 and Thrane & Thrane Sailor VMS Silver. Approved E-MTU VMS and Communications Service Providers The...

2011-12-02

430

MOBILE MONITORING SYSTEM FOR GASEOUS AIR POLLUTION  

Microsoft Academic Search

The concept of a mobile monitoring system for chemical agents control in the air is presented. The proposed system can be applied to measure industrial and car traffic air pollution. A monitoring station is relatively small and can be placed on cars or public transportation vehicles. Measured concent rations of air pollutants are collected and transferred via the GSM network

G. Narutowicza Informatics

431

Maximum likelihood sequence estimation of quadrature pulse-overlapping modulated signals for portable/mobile satellite communications  

NASA Astrophysics Data System (ADS)

A maximum likelihood sequence estimation (MLSE) receiver for constant-envelope hardlimited quadrature pulse-overlapping modulated (QPOM) signals is presented. Its performance is analyzed for both AWGN and Rayleigh fading channels and then verified by computer simulations. The quadrature pulse-overlapping modulation is first decomposed into a linear encoder followed by a memoryless modulator. A trellis diagram that describes this inherent nonredundant coding structure is then used to construct the MLSE receiver. Results of the performance analysis indicate that the scheme outperforms conventional QPSK techniques in fading channels. It is concluded that the constant-envelope compact spectrum superior performance in fading channels and low complexity make the hardlimited QPOM scheme a good choice for portable and mobile satellite communication systems.

Slimane, S. B.; Le-Ngoc, Tho

1992-10-01

432

The generation of simple compliance boundaries for mobile communication base station antennas using formulae for SAR estimation  

NASA Astrophysics Data System (ADS)

In this paper, a procedure is proposed for generating simple and practical compliance boundaries for mobile communication base station antennas. The procedure is based on a set of formulae for estimating the specific absorption rate (SAR) in certain directions around a class of common base station antennas. The formulae, given for both whole-body and localized SAR, require as input the frequency, the transmitted power and knowledge of antenna-related parameters such as dimensions, directivity and half-power beamwidths. With knowledge of the SAR in three key directions it is demonstrated how simple and practical compliance boundaries can be generated outside of which the exposure levels do not exceed certain limit values. The conservativeness of the proposed procedure is discussed based on results from numerical radio frequency (RF) exposure simulations with human body phantoms from the recently developed Virtual Family.

Thors, B.; Hansson, B.; Törnevik, C.

2009-07-01

433

Linkage to HIV, TB and Non-Communicable Disease Care from a Mobile Testing Unit in Cape Town, South Africa  

PubMed Central

Background HIV counseling and testing may serve as an entry point for non-communicable disease screening. Objectives To determine the yield of newly-diagnosed HIV, tuberculosis (TB) symptoms, diabetes and hypertension, and to assess CD4 count testing, linkage to care as well as correlates of linkage and barriers to care from a mobile testing unit. Methods A mobile unit provided screening for HIV, TB symptoms, diabetes and hypertension in Cape Town, South Africa between March 2010 and September 2011. The yield of newly-diagnosed cases of these conditions was measured and clients were followed-up between January and November 2011 to assess linkage. Linkage to care was defined as accessing care within one, three or six months post-HIV diagnosis (dependent on CD4 count) and one month post-diagnosis for other conditions. Clinical and socio-demographic correlates of linkage to care were evaluated using Poisson regression and barriers to care were determined. Results Of 9,806 clients screened, the yield of new diagnoses was: HIV (5.5%), TB suspects (10.1%), diabetes (0.8%) and hypertension (58.1%). Linkage to care for HIV-infected clients, TB suspects, diabetics and hypertensives was: 51.3%, 56.7%, 74.1% and 50.0%. Only disclosure of HIV-positive status to family members or partners (RR=2.6, 95% CI: 1.04-6.3, p=0.04) was independently associated with linkage to HIV care. The main barrier to care reported by all groups was lack of time to access a clinic. Conclusion Screening for HIV, TB symptoms and hypertension at mobile units in South Africa has a high yield but inadequate linkage. After-hours and weekend clinics may overcome a major barrier to accessing care. PMID:24236170

Govindasamy, Darshini; Kranzer, Katharina; van Schaik, Nienke; Noubary, Farzad; Wood, Robin; Walensky, Rochelle P.; Freedberg, Kenneth A.; Bassett, Ingrid V.; Bekker, Linda-Gail

2013-01-01

434

Supplanting copper : pricing and quality of GSM telecom services in Africa  

E-print Network

Introduction: The mobile phone is one of the greatest innovations of the 2 0 th century. It allows a user to communicate information - data and voice - regardless of their geographical location. Its importance has grown ...

Oyeyinka, Oyebanke (Oyebanke Nihinlolawa)

2008-01-01

435

Temporal scalable mobile video communications based on an improved WZ-to-SVC transcoder  

NASA Astrophysics Data System (ADS)

Wyner-Ziv (WZ) to scalable video coding (SVC) transcoding can offer a suitable framework to support scalable video communications between low-cost devices. In addition, the video delivery provided by SVC covers the needs of a wide range of homogeneous networks and different devices. Despite the advantages of the video transcoding framework, the transcoder accumulates high complexity and it must be reduced in order to avoid excessive delays in communication. In this article, an approach for WZ to SVC transcoding is presented. The information generated during the first stage is reused during the second one, and as a consequence the time taken by the transcoding is reduced by around 77.77%, with a negligible rate-distortion penalty.

Corrales-García, Alberto; Martínez, José Luis; Fernández-Escribano, Gerardo; Quiles, Francisco José

2013-12-01

436

Media Affordances of a Mobile Push-To-Talk Communication Service  

Microsoft Academic Search

This paper presents an exploratory study of college-age students using two- way, push-to-talk cellular radios. We describe the observed and reported use of cellular radio by the participants, the activities and purposes for which they adopted it, and their responses. We then examine these empirical results using mediated communication theory. Cellular radios have a unique combination of affordances relative to

Allison Woodruff; Paul M. Aoki

2003-01-01

437

Improving communication and social support for caregivers of high-risk infants through mobile technologies  

Microsoft Academic Search

Upon leaving the hospital, parents of high-risk infants experience a variety of challenges in providing care at home. In this work, we present results from a qualitative study to understand the role of social interaction and information-sharing surrounding high-risk infants among both home caregivers and health professionals. These results demonstrate challenges in communication and social support for caregivers of these

Leslie S. Liu; Sen H. Hirano; Monica Tentori; Karen G. Cheng; Sheba George; Sun Young Park; Gillian R. Hayes

2011-01-01

438

A development of GMSK\\/TDMA system with CMA adaptive array for land mobile communications  

Microsoft Academic Search

The authors describe a hardware implementation of a GMSK\\/TDMA (Gaussian minimum-shift keying\\/time-division multiple-access) communication system and show the bit error rate (BER) performance of the system. This system employs a modulation data rate of 256 kb\\/s and accommodates 24 users\\/carrier. In order to reduce the effect of multipath fading, an adaptive array which has four antenna elements is implemented using

T. Ohgane; H. Sasaoka; N. Matsuzawa; K. Takeda; T. Shimura

1991-01-01

439

QoS-oriented access control for 4G mobile multimedia CDMA communications  

Microsoft Academic Search

An efficient medium access control protocol with fair packet loss sharing packet scheduling is proposed for wireless code-division multiple access communications. The proposed MAC protocol exploits both time-division and code-division statistical multiplexing. The FPLS scheduler uses the information of traffic rate distribution and quality of service requirements to assign priorities to the users and determines an efficient combination of the

Vincent Huang; Weihua Zhuang

2002-01-01

440

Performance of band-limited 16-ary DEQAM transmission over mobile satellite communication links  

NASA Astrophysics Data System (ADS)

The paper presents the results of a computer simulation study on the performance of 16-ary differentially encoded quadrature-amplitude-modulation (16-ary DEQAM) through nonlinear satellite channels, in the presence of additive white Gaussian noise (AWGN) and adjacent-channel-interference (ACI). It is assumed that the satellite transponder is linear, and each of the earth stations uses a newly developed solid-state power amplifier (SSPA) for high power amplification. The results are compared with those of a 16-ary DEQAM system employing a conventional travelling wave tube amplifier (TWTA). Results indicate that 16-ary DEQAM transmission for mobile satellite systems employing SSPA's is promising.

Cheung, S. W.; Aghvami, A. H.

441

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

The 17th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'06) 1-4244-0330-8/06/$20.00 c2006 IEEE DESIGN OF THE DIGITAL BLOCK OF A HARDWARE SIMULATOR 14315 35043 Rennes cedex France sylvie.picol@ens.insa-rennes.fr ABSTRACT The aim of the regional

Boyer, Edmond

442

Electromagnetic hypersensitivity (EHS) and subjective health complaints associated with electromagnetic fields of mobile phone communication—a literature review published between 2000 and 2004  

Microsoft Academic Search

Literature published between 2000 to 2004 concerning electromagnetic fields (EMF) of mobile communication and electromagnetic hypersensitivity (EHS) or unspecific symptoms of ill health, respectively, is reviewed. Basically, literature from established databases was systematically searched for. For each study, the design and quality were evaluated by means of a criteria list in order to judge evidence for causality of exposures on

H. Seitz; D. Stinner; Th. Eikmann; C. Herr; M. Röösli

2005-01-01

443

A second anniversary operational review of the OmniTRACS(R): The first two-way mobile Ku-band satellite communications system  

NASA Technical Reports Server (NTRS)

A novel two-way mobile satellite communications and vehicle position reporting system that is currently operational in the United States and Europe is described. The system characteristics and service operations are described in detail. Technical descriptions of the equipment and signal processing techniques are provided.

Jacobs, Irwin M.; Salmasi, Allen; Gilhousen, Klein S.; Weaver, Lindsay A., Jr.; Bernard, Thomas J.

1990-01-01

444

Improved performance of UDP & TCP throughput in Wi-Fi networks for voice and data services in mobile communications with MIMO systems  

Microsoft Academic Search

Exponential addition of the customers and limited bandwidth available for Mobile Communications results in increased blocking probability on the network. To decrease the blocking probability the voice services and data services are accessed with two different networks. Normally the essential network is cellular network and the second is Wi-Fi network. We categorize Access Points [AP] as Root, Non Root and

P. Venkat Ramana; S. Narayana Reddy

2012-01-01

445

A Method to Improve the Radiation Patterns of the Base-Station Sector Antenna for Mobile Communications by Adding Scattering Structures on the Front Panel of the Antenna  

Microsoft Academic Search

A finite difference time domain software package, called XFDTD, is applied to study the characteristics of the base-station sector antennas for mobile communications. The XFDTD simulation software was employed to design several different metal structures for the scattering surfaces, located on the front panels of the base-station antennas. Without varying the appearance and dimensions of the antennas, the scattering surfaces

Cheng-Hsiung Wu; Chang-Fa Yang; Te-Shun Wang; Kuan-Chi Liao; Yen-Ming Chen

2006-01-01

446

Combined coding and delay-throughput analysis for fading channels of mobile satellite communications  

NASA Technical Reports Server (NTRS)

This paper presents the analysis of using the punctured convolutional code with Viterbi decoding to improve communications reliability. The punctured code rate is optimized so that the average delay is minimized. The coding gain in terms of the message delay is also defined. Since using punctured convolutional code with interleaving is still inadequate to combat the severe fading for short packets, the use of multiple copies of assignment and acknowledgment packets is suggested. The performance on the average end-to-end delay of this protocol is analyzed. It is shown that a replication of three copies for both assignment packets and acknowledgment packets is optimum for the cases considered.

Wang, C. C.; Yan, Tsun-Yee

1986-01-01

447

Performance and operational considerations in the design of vehicle antennas for mobile satellite communications  

NASA Technical Reports Server (NTRS)

This paper examines the vehicle antenna requirements for mobile satellite systems. The antenna parameters are discussed in the light of the requirements and the limitations in performance imposed by the physical constraints of antenna and by vehicle geometries. Measurements of diffraction and antenna noise temperature in an operational environment are examined, as well as their effects on system margins. Mechanical versus electronic designs are compared with regards to performance, cost, reliability, and design complexity. Comparisons between open-loop and close-loop tracking systems are made and the effects of bandwidth, sidelobe levels, operational constraints, vehicle angular velocity, and acceleration are discussed. Some consideration is given to the use of hybrid systems employing both open and closed-loop tracking. Changes to antenna/terminal specifications are recommended which will provide greater design flexibility and increase the likelihood of meeting the performance and operational requirements.

Milne, R.

1995-01-01

448

0.25-?m technology arithmetic codec for mobile multimedia communicators  

NASA Astrophysics Data System (ADS)

Low power dissipation is a must when dealing with mobile devices due to the influence related to its weight and hence, its portability. In this paper, the implementation of a 0.25 mm technology arithmetic codec with a good power/area/performance trade-off is presented. One of the key aspects introduced in order to obtain good performance is the fact of using low precision arithmetic rather than full precision, allowing the elimination of multiplications and divisions needed in order to process symbols and coefficients. These operations are replaced by shift/add operations, minimizing the complexity of the algorithm and improving the encoding and decoding process. The chip has been described in a high level language, ensuring its portability to other technologies. The implementation gives as result a 25 mm2 chip, pads included, with a total power dissipation of 300 mW and a frequency of operation of 10 MHz.

Alvarez, Alberto; Lopez, Sebastian; Lopez, Jose F.; Sarmiento, Roberto

2003-04-01

449

A Low-Cost GPS GSM/GPRS Telemetry System: Performance in Stationary Field Tests and Preliminary Data on Wild Otters (Lutra lutra)  

PubMed Central

Background Despite the increasing worldwide use of global positioning system (GPS) telemetry in wildlife research, it has never been tested on any freshwater diving animal or in the peculiar conditions of the riparian habitat, despite this latter being one of the most important habitat types for many animal taxa. Moreover, in most cases, the GPS devices used have been commercial and expensive, limiting their use in low-budget projects. Methodology/Principal Findings We have developed a low-cost, easily constructed GPS GSM/GPRS (Global System for Mobile Communications/General Packet Radio Service) and examined its performance in stationary tests, by assessing the influence of different habitat types, including the riparian, as well as water submersion and certain climatic and environmental variables on GPS fix-success rate and accuracy. We then tested the GPS on wild diving animals, applying it, for the first time, to an otter species (Lutra lutra). The rate of locations acquired during the stationary tests reached 63.2%, with an average location error of 8.94 m (SD?=?8.55). GPS performance in riparian habitats was principally affected by water submersion and secondarily by GPS inclination and position within the riverbed. Temporal and spatial correlations of location estimates accounted for some variation in the data sets. GPS-tagged otters also provided accurate locations and an even higher GPS fix-success rate (68.2%). Conclusions/Significance Our results suggest that GPS telemetry is reliably applicable to riparian and even diving freshwater animals. They also highlight the need, in GPS wildlife studies, for performing site-specific pilot studies on GPS functioning as well as for taking into account eventual spatial and temporal correlation of location estimates. The limited price, small dimensions, and high performance of the device presented here make it a useful and cost-effective tool for studies on otters and other aquatic or terrestrial medium-to-large-sized animals. PMID:22242163

Quaglietta, Lorenzo; Martins, Bruno Herlander; de Jongh, Addy; Mira, Antonio; Boitani, Luigi

2012-01-01

450

Design of a multiband internal antenna for third generation mobile phone handsets  

Microsoft Academic Search

A multiband internal antenna is introduced. The antenna consists of a driven meander-line element and two parasitic elements. The design is particularly unique since it supports the third generation mobile phone handsets where multiband operation is greatly desired. The proposed antenna operates effectively in the AMPS 800 (824-894 MHz), GSM 900 (880-960 MHz), and GSM 1900 (1850-1990 MHz) bands within

Mohammod Ali; Gerard James Hayes; Huan-Sheng Hwang; Robert A. Sadler

2003-01-01

451

Comparative international analysis of radiofrequency exposure surveys of mobile communication radio base stations  

PubMed Central

This paper presents analyses of data from surveys of radio base stations in 23 countries across five continents from the year 2000 onward and includes over 173,000 individual data points. The research compared the results of the national surveys, investigated chronological trends and compared exposures by technology. The key findings from this data are that irrespective of country, the year and cellular technology, exposures to radio signals at ground level were only a small fraction of the relevant human exposure standards. Importantly, there has been no significant increase in exposure levels since the widespread introduction of 3G mobile services, which should be reassuring for policy makers and negate the need for post-installation measurements at ground level for compliance purposes. There may be areas close to antennas where compliance levels could be exceeded. Future potential work includes extending the study to additional countries, development of cumulative exposure distributions and investigating the possibility of linking exposure measurements to population statistics to assess the distribution of exposure levels relative to population percentiles. PMID:22377680

Rowley, Jack T; Joyner, Ken H

2012-01-01

452

A transport protocol to improve access to data networks from GSM using a proxy  

E-print Network

as a bridge between GSM and the rest of the data network. We have replaced the TCP connection in the client Abstract In order to access TCP/IP networks (mainly the Internet) through GSM links,. we have designed an architecture based in the indirect model of client/server interaction, where an intermediate element acts

Miguel-Alonso, José

453

Distortion-class modeling for robust speech recognition under GSM RPE-LTP coding  

E-print Network

Distortion-class modeling for robust speech recognition under GSM RPE-LTP coding Juan M. Huerta in recognition accuracy introduced by full-rate GSM RPE-LTP coding by combining sets of acoustic models trained the spectral distortion introduced to the quantized long-term residual by the RPE-LTP codec. We discuss how

Stern, Richard

454

Splitting GSM Schemas: A Framework for Outsourcing of Declarative Artifact Systems  

E-print Network

, Richard Hull2 , Yutian Sun3 , and Roman Vacul�in2 1 School of Industrial Engineering, Eindhoven and outsourcing of GSM schemas. One element of the framework focuses on restructuring the GSM schema to facilitate. The rules restructuring developed here enables a crisp separation of concerns, which allows reuse

California at Santa Barbara, University of

455

Pointing, acquisition, and tracking considerations for mobile directional wireless communications systems  

NASA Astrophysics Data System (ADS)

High capacity directional wireless communications networks are an active research area because of their Gb/s or greater data rates over link lengths of many kilometers, providing fiber-like networks through the air. Their high data rates arise partly from their very high carrier frequencies (<60GHz for RF, and ~1550nm for free-space optical (FSO)) and partly because of their very narrow beamwidths. This second characteristic requires that transceivers be pointed precisely to their counterparts. In almost all cases this means that the transceiver aperture is mechanically pointed by a rotation stage, commonly known as a gimbal. How these platforms initially point at a target, acquire the signal, and then stay locked on the signal is known as pointing, acquisition, and tracking (PAT). Approaches for PAT in both RF and FSO have some similarities, but require overall divergent solutions, especially if the platforms are moving. This paper elaborates on the various considerations required for designing and implementing a successful PAT system for both directional RF and FSO systems. Approaches for GPS or beacon based pointing, types of acquisition scans, and the effects of platform vibration are analyzed. The acquisition time for a spiral scan of a given radius with an initial pointing error has been measured experimentally for a gimbal pointing system.

Rzasa, John; Ertem, Mehmet Can; Davis, Christopher C.

2013-09-01

456

Dual-port serial arbiter with GSM modules for simultaneous local/remote control of RS232-  

E-print Network

commercial GSM/GPRS modems. There are an important number of modem producers but most of them use inside-485, Ethernet, USB, FireWire, Bluetooth, IEEE 802.11, GSM/GPRS, I2C, et cetera. These modules act totally the common characteristics of GSM/GPRS modules and to devise the adopted solution. A. Common characteristics

Autònoma de Barcelona, Universitat

457

Communications.  

ERIC Educational Resources Information Center

Five articles discussing communications in vocational education include "The Golden Rule of Administration" by Ben Mortensen; "Vital Link with Parents" by Richard Sullivan; "An Interpersonal Exercise" by John Villiers; "Face to Face with Employers" by Gregg Bosak; and "Recruitment Strategies" by Susan Miller. (SK)

Mortensen, Ben F.; And Others

1981-01-01

458

Microwaves from Mobile Phones Inhibit 53BP1 Focus Formation in Human Stem Cells More Strongly Than in Differentiated Cells: Possible Mechanistic Link to Cancer Risk  

PubMed Central

Background It is widely accepted that DNA double-strand breaks (DSBs) and their misrepair in stem cells are critical events in the multistage origination of various leukemias and tumors, including gliomas. Objectives We studied whether microwaves from mobile telephones of the Global System for Mobile Communication (GSM) and the Universal Global Telecommunications System (UMTS) induce DSBs or affect DSB repair in stem cells. Methods We analyzed tumor suppressor TP53 binding protein 1 (53BP1) foci that are typically formed at the sites of DSB location (referred to as DNA repair foci) by laser confocal microscopy. Results Microwaves from mobile phones inhibited formation of 53BP1 foci in human primary fibroblasts and mesenchymal stem cells. These data parallel our previous findings for human lymphocytes. Importantly, the same GSM carrier frequency (915 MHz) and UMTS frequency band (1947.4 MHz) were effective for all cell types. Exposure at 905 MHz did not inhibit 53BP1 foci in differentiated cells, either fibroblasts or lymphocytes, whereas some effects were seen in stem cells at 905 MHz. Contrary to fibroblasts, stem cells did not adapt to chronic exposure during 2 weeks. Conclusions The strongest microwave effects were always observed in stem cells. This result may suggest both significant misbalance in DSB repair and severe stress response. Our findings that stem cells are most sensitive to microwave exposure and react to more frequencies than do differentiated cells may be important for cancer risk assessment and indicate that stem cells are the most relevant cellular model for validating safe mobile communication signals. PMID:20064781

Markova, Eva; Malmgren, Lars O.G.; Belyaev, Igor Y.

2010-01-01

459

Beam control method based on omni-directional regular icosahedron-shaped optical antenna for mobile free-space optical communication  

NASA Astrophysics Data System (ADS)

In order to ensure the communication link stability in mobile free-space optical communication (FSO) system, a novel omni-directional regular icosahedron-shaped optical antenna is designed and its beam control method is proposed. The beam control strategy is studied in detail, which includes the switch between the transmission units on the same transmitting surface and the switch between the transmitting surfaces, and the numerical simulations are carried out. When the movement of the antenna is random and the number of the transmission units in each transmitting surface is designed as 820, the number of the transmission units on the same surface changes from 0 to 560 and the number of the switched transmitting surfaces is from 1 to 17, which is basically consistent with the actual situation. The results show that the transmission units of the antenna can be switched effectively according to the terminal's movement. Our proposed method is suitable for mobile FSO in all-directions.

Shang, Tao; Yang, Yintang; Li, Weixu; Jia, Jijun; Wang, Xin

2012-10-01

460

A resource management strategy in wireless multimedia communications-total power saving in mobile terminals with a guaranteed QoS  

Microsoft Academic Search

The integration of multimedia services into wireless communication networks is a major source of future technological advances. One of the main challenging issues in this endeavor is the resource optimization strategy. This paper addresses this issue from the perspective of minimizing the total power consumption of a mobile terminal while maintaining a guaranteed quality-of-service (QoS). For many years, the management

Tse-hua Lan; Ahmed H. Tewfik

2003-01-01

461

In-vitro exposure of neuronal networks to the GSM-1800 signal.  

PubMed

The central nervous system is the most likely target of mobile telephony radiofrequency (RF) field exposure in terms of biological effects. Several electroencephalography (EEG) studies have reported variations in the alpha-band power spectrum during and/or after RF exposure, in resting EEG and during sleep. In this context, the observation of the spontaneous electrical activity of neuronal networks under RF exposure can be an efficient tool to detect the occurrence of low-level RF effects on the nervous system. Our research group has developed a dedicated experimental setup in the GHz range for the simultaneous exposure of neuronal networks and monitoring of electrical activity. A transverse electromagnetic (TEM) cell was used to expose the neuronal networks to GSM-1800 signals at a SAR level of 3.2 W/kg. Recording of the neuronal electrical activity and detection of the extracellular spikes and bursts under exposure were performed using microelectrode arrays (MEAs). This work provides the proof of feasibility and preliminary results of the integrated investigation regarding exposure setup, culture of the neuronal network, recording of the electrical activity, and analysis of the signals obtained under RF exposure. In this pilot study on 16 cultures, there was a 30% reversible decrease in firing rate (FR) and bursting rate (BR) during a 3 min exposure to RF. Additional experiments are needed to further characterize this effect. PMID:23913345

Moretti, Daniela; Garenne, André; Haro, Emmanuelle; Poulletier de Gannes, Florence; Lagroye, Isabelle; Lévęque, Philippe; Veyret, Bernard; Lewis, Noëlle

2013-12-01

462

Long-term exposure to microwave radiation provokes cancer growth: evidences from radars and mobile communication systems.  

PubMed

In this review we discuss alarming epidemiological and experimental data on possible carcinogenic effects of long term exposure to low intensity microwave (MW) radiation. Recently, a number of reports revealed that under certain conditions the irradiation by low intensity MW can substantially induce cancer progression in humans and in animal models. The carcinogenic effect of MW irradiation is typically manifested after long term (up to 10 years and more) exposure. Nevertheless, even a year of operation of a powerful base transmitting station for mobile communication reportedly resulted in a dramatic increase of cancer incidence among population living nearby. In addition, model studies in rodents unveiled a significant increase in carcinogenesis after 17-24 months of MW exposure both in tumor-prone and intact animals. To that, such metabolic changes, as overproduction of reactive oxygen species, 8-hydroxi-2-deoxyguanosine formation, or ornithine decarboxylase activation under exposure to low intensity MW confirm a stress impact of this factor on living cells. We also address the issue of standards for assessment of biological effects of irradiation. It is now becoming increasingly evident that assessment of biological effects of non-ionizing radiation based on physical (thermal) approach used in recommendations of current regulatory bodies, including the International Commission on Non-Ionizing Radiation Protection (ICNIRP) Guidelines, requires urgent reevaluation. We conclude that recent data strongly point to the need for re-elaboration of the current safety limits for non-ionizing radiation using recently obtained knowledge. We also emphasize that the everyday exposure of both occupational and general public to MW radiation should be regulated based on a precautionary principles which imply maximum restriction of excessive exposure. PMID:21716201

Yakymenko, I; Sidorik, E; Kyrylenko, S; Chekhun, V

2011-06-01

463

Communication Communication  

E-print Network

Communication Seminar Stanford University April 16, 2001 1 #12; Wireless Communication Theory . Wireless communication theory is having a renaissance in the past decade. . Much of it is centered around how to communicate e#ectively over fading channels. . A modern view of communication over fading channels is emerging

Tse, David

464

ROUTE NAVIGATOR: PATH FINDER SERVICE FOR MOBILE PHONE  

Microsoft Academic Search

Route Navigator is an automated mobile path finder service which aims to provide text direction and map direction through the use of SMS or MMS by using existing services offered by the carrier networks like Sun, Globe and Smart. Users of the service will send a request for path in the proponent's gateway (the gateway is usually a GSM modem

Paolo Alekseis; P. Carolino; Juan Carlos; L. Guevarra; Joemerick B. San Gabriel

465

Privacy in mobile applications and beyond Journe ADREAM,  

E-print Network

is stored therein and is furnished upon request to the other appliances. [United States Patent 5410471, www;......... 4 Child Watch II #12;......... 5 Child Watch III Children have GSM-GPS system on wrist. Price: US ... in Chile marketed by a mobile operator (Entel PCS) #12;......... 7 For Senior Citizens also ... #12

Ingrand, François

466

Preserving User Location Privacy in Mobile Data Management Infrastructures  

E-print Network

the Global Positioning Systems (GPS), GSM, RF- ID and the Wireless LAN have undergone rapid developments and items accurately also raises a new concern ­ intrusion of location privacy. According to [4], locationPreserving User Location Privacy in Mobile Data Management Infrastructures Reynold Cheng1 , Yu

Cheng, Reynold Cheng Chun

467

Fuzzy Logic based Handoff Latency Reduction Mechanism in Layer 2 of Heterogeneous Mobile IPv6 Networks  

NASA Astrophysics Data System (ADS)

Mobile IPv6 (MIPv6) is one of the pioneer standards that support mobility in IPv6 environment. It has been designed to support different types of technologies for providing seamless communications in next generation network. However, MIPv6 and subsequent standards have some limitations due to its handoff latency. In this paper, a fuzzy logic based mechanism is proposed to reduce the handoff latency of MIPv6 for Layer 2 (L2) by scanning the Access Points (APs) while the Mobile Node (MN) is moving among different APs. Handoff latency occurs when the MN switches from one AP to another in L2. Heterogeneous network is considered in this research in order to reduce the delays in L2. Received Signal Strength Indicator (RSSI) and velocity of the MN are considered as the input of fuzzy logic technique. This technique helps the MN to measure optimum signal quality from APs for the speedy mobile node based on fuzzy logic input rules and makes a list of interfaces. A suitable interface from the list of available interfaces can be selected like WiFi, WiMAX or GSM. Simulation results show 55% handoff latency reduction and 50% packet loss improvement in L2 compared to standard to MIPv6.

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

2013-12-01

468

Near Field Communication and Health: Turning a Mobile Phone into an Interactive Multipurpose Assistant in Healthcare Scenarios  

NASA Astrophysics Data System (ADS)

In this paper we discuss the introduction of the Near Field Communication (NFC) technology in the management of the assistance operations in the hospitals. NFC is a new short range communication system based on RFID technology.

Benelli, Giuliano; Pozzebon, Alessandro

469

Two Low-Cost Solutions for Cardiac Mobile Monitoring  

Microsoft Academic Search

\\u000a A small device, named WalkECG, developed for out-of-hospital cardiac monitoring, is presented. Two models were developed,\\u000a one including an embedded GSM\\/GPRS modem and a second model which is able to set a Bluetooth connection with a mobile phone.\\u000a The device is based on the MSP430F1611 microcontroller and includes a two-channel ECG amplifier, a graphic LCD, a keypad,\\u000a a GSM\\/GPRS embedded

R. I. Gonzalez; R. Guardarrama; F. Leon; A. Rodriguez; D. Jimenez

470

Panel antennas for remote user terminals of GSM1800 cellular network  

Microsoft Academic Search

High antenna gain, construction simplicity, transportation comfort and comparatively low cost are the main advantages of the developed panel antennas. They can be used for increasing user terminal operating range within the cellular network GSM-1800.

A. S. Mikrukov; V. F. Korsak; I. A. Byichkov; V. I. Markin

2000-01-01

471

Alterations in TSH and Thyroid Hormones following Mobile Phone Use  

PubMed Central

Objectives In recent years, the widespread use of mobile phones has lead to a public debate about possible detrimental effects on human health. In spite of years of research, there is still a great controversy regarding the possibility of induction of any significant physiological effects in humans by microwave radiations emitted by mobile phones. This study aims to investigate the effects of electromagnetic fields induced by the Global System for Mobile communications (GSM) mobile phones on the Thyroid Stimulating Hormone (TSH) and thyroid hormones in humans. Methods 77 healthy university students participated in this study. The levels of T3, T4 and TSH were measured by using appropriate enzyme-linked immunosorbent assay (ELISA) kits (Human, Germany). Results The average levels of T3, T4 and TSH in students who moderately used mobile phones were 1.25±0.27 ng/ml, 7.76±1.73 µg/dl and 4.25±2.12 µu/l respectively. The levels in the students who severely used mobile phones were 1.18±0.30, 7.75±1.14 and 3.75±2.05 respectively. In non-users, the levels were 1.15±0.27, 8.42±2.72 and 2.70±1.75, respectively. The difference among the levels of TSH in these 3 groups was statistically significant (P<0.05). Conclusion As far as the study is concerned, this is the first human study to assess the associations between mobile phone use and alterations in the levels of TSH and thyroid hormones. Based on the findings, a higher than normal TSH level, low mean T4 and normal T3 concentrations in mobile users were observed. It seems that minor degrees of thyroid dysfunction with a compensatory rise in TSH may occur following excessive use of mobile phones. It may be concluded that possible deleterious effects of mobile microwaves on hypothalamic-pituitary-thyroid axis affects the levels of these hormones. PMID:22216380

Mortavazi, Seyed; Habib, Asadollah; Ganj-Karami, Amir; Samimi-Doost, Razieh; Pour-Abedi, Atefe; Babaie, Ali

2009-01-01

472

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

ERIC Educational Resources Information Center

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…

Horta, Hugo; Yonezawa, Akiyoshi

2013-01-01

473

664 IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 22, NO. 4, MAY 2004 Dynamic Hierarchical Mobility Management Strategy  

E-print Network

10.1109/JSAC.2004.825968 are predominantly based on Internet protocol (IP) [1], [2]. The popularity Internet protocol (IP) is a commonly accepted standard to address global mobility of mobile hosts (MHs robustness is greatly enhanced. Our analysis also shows that the new scheme can outperform the Internet

Latchman, Haniph A.

474

Outage Probability in GSM-GPRS Cellular Systems With and Without Frequency Hopping  

Microsoft Academic Search

General packet radio service(GPRS) is designed for transmitting packet data andis supposed to take its radio resource from the pool ofunused channels of GSM voice services. Obviously, theintroduction of GPRS has an impact on the voice services.In this paper, we present a method to calculate theoutage probability of the GSM-GPRS network for bothnon-frequency hopping and frequency hoppingsystems. This method takes

Shaoji Ni; Yong Liang; Sven-Gustav Häggman

2000-01-01

475

A transport protocol to improve access to data networks from GSM using a proxy  

Microsoft Academic Search

In order to access TCP\\/IP networks (mainly the Internet) through GSM links,. we have designed an architecture based in the indirect model of client\\/server interaction, where a n intermediate e lement acts as a bridge between GSM and the rest of the data network. We have replaced the TCP connection in the c lient-proxy link with a simpler protocol. This

J. M. Rivadeneyra Sicilia; J. Miguel-Alonso

2000-01-01

476

Enhanced protocols for pedagogical through mobile learning  

Microsoft Academic Search

This paper is intended for on how mobile technologies can play an important role in the evolution of M-learning. In Second Generation, GSM can be introduced in three ways such as general packet radio services, continuous connection to the internet not requiring dial-up connection reaching up to 171.2 Kbits \\/s. Secondly, Blue tooth is a chip technology, that allows short

S. Neduncheliyan; T. C. Manjunath

2007-01-01

477

Efficacy of communication amongst staff members at plastic and reconstructive surgery section using smartphone and mobile WhatsApp  

PubMed Central

Objective: The objective of this study is to assess the efficacy of smartphone and its WhatsApp application as a communication method amongst the staff of plastic and reconstructive surgery section at tertiary care health facility. Materials and Methods: From January 2012 onwards, the authors used smartphones and its WhatsApp application as a communication method amongst their team for various aspects of patient management and as a tool for academic endorsements. Results: During the period of this study, there were 116 episodes regarding patient management, which were handled, in a timely fashion by using this application. In addition opinion of rotating residents in the section was sought regarding the efficacy of this method of communication. Overall majority of residents were satisfied with this mode of communication. Conclusions: This new method of communication is an effective method for clinical and academic endorsements. The method is cheap and quick and easy to operate. PMID:24459338

Wani, Shabeer Ahmad; Rabah, Sari M.; AlFadil, Sara; Dewanjee, Nancy; Najmi, Yahya

2013-01-01

478

Smartphones Enabling Mobile Collaboration  

Microsoft Academic Search

Mobilization of the work-force is demanding new mobile and wireless technologies to facilitate contact between the growing number of mobile eWorkers and organizations. Smartphones incorporating mobile e-mail functionality enable instant access to e-mail boxes and company resources without complex synchronization. A study amongst sixteen German companies was conducted to elicit the influence of mobile e-mail on work-processes and communication. The

Bettina Beurer-zuellig; Miriam Meckel

2008-01-01

479

Land Mobile Satellite Service (LMSS) channel simulator: An end-to-end hardware simulation and study of the LMSS communications links  

NASA Technical Reports Server (NTRS)

The design and implementation of the Land Mobile Satellite Service (LMSS) channel simulator as a facility for an end to end hardware simulation of the LMSS communications links, primarily with the mobile terminal is described. A number of studies are reported which show the applications of the channel simulator as a facility for validation and assessment of the LMSS design requirements and capabilities by performing quantitative measurements and qualitative audio evaluations for various link design parameters and channel impairments under simulated LMSS operating conditions. As a first application, the LMSS channel simulator was used in the evaluation of a system based on the voice processing and modulation (e.g., NBFM with 30 kHz of channel spacing and a 2 kHz rms frequency deviation for average talkers) selected for the Bell System's Advanced Mobile Phone Service (AMPS). The various details of the hardware design, qualitative audio evaluation techniques, signal to channel impairment measurement techniques, the justifications for criteria of different parameter selection in regards to the voice processing and modulation methods, and the results of a number of parametric studies are further described.

Salmasi, A. B. (editor); Springett, J. C.; Sumida, J. T.; Richter, P. H.

1984-01-01

480

75 FR 32984 - Policy on the Retention of Supporting Documents and the Use of Electronic Mobile Communication...  

Federal Register 2010, 2011, 2012, 2013

...Positioning Systems (GPS) or other electronic...communication/tracking technology during the ordinary...used the terms ``GPS'' and ``Advanced Information Technology'' to describe electronic...systems may rely on technology other than GPS to determine...

2010-06-10

481

Troposphere communications  

NASA Astrophysics Data System (ADS)

The physical processes and features of troposphere radiowave propagation are reviewed, and fundamental principles for the construction of troposphere lines of communication are discussed. The technical characteristics of troposphere stations in the USA, England, France, FRG, and Japan are studied and compared. Attention is given to mobile and stationary military stations, and to stationary troposphere communication systems in the Americas, Greenland, the Caribbean islands, Asia, Africa, and Australia. Developments in troposphere communications, including the AN/TRC-170 station, are discussed.

Iakovlev, L. I.; Dediukin, G. V.; Kagramanov, E. S.; Redin, A. P.; Stuton, P. I.; Tsybulkin, L. D.

482

Exposure to GSM RF fields does not affect calcium homeostasis in human endothelial cells, rat pheocromocytoma cells or rat hippocampal neurons.  

PubMed

In the course of modern daily life, individuals are exposed to numerous sources of electromagnetic radiation that are not present in the natural environment. The strength of the electromagnetic fields from sources such as hairdryers, computer display units and other electrical devices is modest. However, in many home and office environments, individuals can experience perpetual exposure to an "electromagnetic smog", with occasional peaks of relatively high electromagnetic field intensity. This has led to concerns that such radiation can affect health. In particular, emissions from mobile phones or mobile phone masts have been invoked as a potential source of pathological electromagnetic radiation. Previous reports have suggested that cellular calcium (Ca2+) homeostasis is affected by the types of radiofrequency fields emitted by mobile phones. In the present study, we used a high-throughput imaging platform to monitor putative changes in cellular Ca2+ during exposure of cells to 900 MHz GSM fields of differing power (specific absorption rate 0.012-2 W/Kg), thus mimicking the type of radiation emitted by current mobile phone handsets. Data from cells experiencing the 900 Mhz GSM fields were compared with data obtained from paired experiments using continuous wave fields or no field. We employed three cell types (human endothelial cells, PC-12 neuroblastoma and primary hippocampal neurons) that have previously been suggested to be sensitive to radiofrequency fields. Experiments were designed to examine putative effects of radiofrequency fields on resting Ca2+, in addition to Ca2+ signals evoked by an InsP(3)-generating agonist. Furthermore, we examined putative effects of radiofrequency field exposure on Ca2+ store emptying and store-operated Ca2+ entry following application of the Ca2+ATPase inhibitor thapsigargin. Multiple parameters (e.g., peak amplitude, integrated Ca2+ signal, recovery rates) were analysed to explore potential impact of radiofrequency field exposure on Ca2+ signals. Our data indicate that 900 MHz GSM fields do not affect either basal Ca2+ homeostasis or provoked Ca2+ signals. Even at the highest field strengths applied, which exceed typical phone exposure levels, we did not observe any changes in cellular Ca2+ signals. We conclude that under the conditions employed in our experiments, and using a highly-sensitive assay, we could not detect any consequence of RF exposure. PMID:20676401

O'Connor, Rodney P; Madison, Steve D; Leveque, Philippe; Roderick, H Llewelyn; Bootman, Martin D

2010-01-01

483

Optimal zonal wavelet-based ECG data compression for a mobile telecardiology system  

Microsoft Academic Search

A new integrated design approach for an optimal zonal wavelet-based ECG data compression (OZWC) method for a mobile telecardiology model is presented. The hybrid implementation issues of this wavelet method with a GSM-based mobile telecardiology system are also introduced. The performance of the mobile system with compressed ECG data segments selected from the MIT-BIH arrhythmia database is evaluated in terms

Robert S. H. Istepanian; Arthur A. Petrosian

2000-01-01

484

ACTS Mobile Terminals  

NASA Technical Reports Server (NTRS)

The development of the Advanced Communications Technology Satellite (ACTS) Mobile Terminal (AMT) and its follow-on, the Broadband Aeronautical Terminal (BAT), have provided an excellent testbed for the evaluation of K- and Ka-band mobile satellite communications systems. An overview of both of these terminals is presented in this paper.

Abbe, Brian S.; Agan, Martin J.; Jedrey, Thomas C.

1997-01-01

485

Unlimited or disrupted communication? How does the development of the mobile phone effect our ability of social action?  

Microsoft Academic Search

The aim of this essay is to discuss the thesis of the German Sociologist Günter Burkhart that in modern societies a phenomenon appeared which he calls “handymania”, an excessive and nearly addictive use of the mobile phones especially from adolescents. After a short overview about the history of the cell phone, I will relate this development to Jürgen Habermas “theory

Marie-Sophie Löhlein

2009-01-01

486

Access to Mobile Communication Technology and Willingness to Participate in Automated Telemedicine Calls Among Chronically Ill Patients in Honduras  

PubMed Central

Abstract Objectives: Patients in underdeveloped countries may be left behind by advances in telehealthcare. We surveyed chronically ill patients with low incomes