Dissertations / Theses: 'Mobile radio'

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Wassell, Ian J. "Digital mobile radio." Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277683.

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Navalekar, Abhijit C. "Distributed Digital Radios for Land Mobile Radio Applications." Digital WPI, 2010. https://digitalcommons.wpi.edu/etd-dissertations/4.

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The main objective of this dissertation is to develop the second generation of Distributed Digital Radio (DDR) technology. A DDR II modem provides an integrated voice/data service platform, higher data rates and better throughput performance as compared to a DDR I modem. In order to improve the physical layer performance of DDR modems an analytical framework is first developed to model the Bit Error Rate (BER) performance of Orthogonal Frequency Division Multiplexing over Frequency Modulation (OFDM/FM) systems. The use of OFDM provides a spectrally efficient method of transmitting data over LMR channels. However, the high Peak-to-Average (PAR) of OFDM signals results in either a low Signal-to-Noise Ratio (SNR) at FM receiver or a high non-linear distortion of baseband signal in the FM transmitter. This dissertation presents an analytical framework to highlight the impact of high PAR of OFDM signal on OFDM/FM systems. A novel technique for reduction of PAR of OFDM called Linear Scaling Technique (LST) is developed. The use of LST mitigates the signal distortion occurring in OFDM over FM systems. Another important factor which affects the throughput of LMR networks is the Push-to-Talk (PTT) delay. A PTT delay refers to the delay between the instant when a PTT switch on a conventional LMR radio is keyed/unkeyed and a response is observed at the radio output. It can be separated into a Receive-To-Transmit Switch Interval (RTSI) or a Transmit-To-Receive Switch Interval (TRSI). This dissertation presents the typical RTSI delay values, distributions and their impact on throughput performance of LMR networks. An analytical model is developed to highlight the asymmetric throughput problem and the unintentional denial of service (UDOS) occurring in heterogeneous LMR networks consisting of radios with different PTT delay profiles. This information will be useful in performance and capacity planning of LMR networks in future.

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Hamied, Khalid Abdul-Ariz. "Advanced radio link design and radio receiver design for mobile communications." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/15940.

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Sowerby, Kevin W. "Outrage probability in mobile radio systems." e-Thesis University of Auckland, 1989. http://hdl.handle.net/2292/2516.

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Karaminas, Panagiotis D. "Array processing in mobile radio networks." Thesis, Imperial College London, 2001. http://hdl.handle.net/10044/1/11483.

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Arnott, Robert. "Array processing for digital mobile radio." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338780.

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Giortzis, Athanasios. "Channel assignment in mobile radio networks." Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266017.

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Arowojolu, Adekunle Andrew. "Microcellular mobile radio measurements and modelling." Thesis, University of Liverpool, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266170.

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Yacoub, M. D. "Mobile radio with fuzzy cell boundaries." Thesis, University of Essex, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381240.

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Foster, Howard Mark Jameson. "High capacity cellular mobile radio systems." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301208.

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11

Chia, S. T. S. "Propagation studies for microcellular mobile radio." Thesis, University of Southampton, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380149.

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Lee, Chin-Chun. "CDMA for cellular mobile radio systems." Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240979.

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Webb, William. "QAM techniques for digital mobile radio." Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385448.

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Pulley, D. R. "Synchronisation for terrestrial mobile radio systems." Thesis, University of Bath, 1993. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760633.

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15

Wang, Li. "TDMA digital mobile radio transmission system." Thesis, University of Liverpool, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240335.

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Toh, Chai-Keong. "Protocol aspects of mobile radio networks." Thesis, University of Cambridge, 1996. https://www.repository.cam.ac.uk/handle/1810/273055.

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Atefi, A. "An investigation of radio wave propagation in mobile radio frequency bands." Thesis, University of Liverpool, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354537.

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Ring, Christoffer. "Detection and Classification of Interference in Mobile Communication Systems." Thesis, Linköpings universitet, Kommunikationssystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-123507.

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The usage of wireless technology has in the past decade vastly increased and it continues to do so as well. Because of this, we become more and more reliant on this considerably fragile technology. Wireless technology, which uses radio waves to transmit data from one point to another can easily be interfered by radio jammers. This thesis work is about the detection and classification of the interference that is produced by jammers over the Global System for Mobile Communications (GSM) air interface. A typical GSM jammer that can be found on the Internet is analyzed but also more advanced GSM jammers are analyzed. The GSM standard is analyzed to find vulnerabilities that a jammer can take advantage of. The result is an interference detector that can be used to detect and classify interference over the GSM networks. The detector is constructed with an Universal Software Radio Peripheral (USRP) but is also portable to other software-defined radio (SDR) platforms.

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Lowes, Philip. "Radio antennas on glass." Thesis, Northumbria University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367424.

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Östlin, Erik. "On Radio Wave Propagation Measurements and Modelling for Cellular Mobile Radio Networks." Doctoral thesis, Karlskrona : Blekinge Institute of Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-00443.

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To support the continuously increasing number of mobile telephone users around the world, mobile communication systems have become more advanced and sophisticated in their designs. As a result of the great success with the second generation mobile radio networks, deployment of the third and development of fourth generations, the demand for higher data rates to support available services, such as internet connection, video telephony and personal navigation systems, is ever growing. To be able to meet the requirements regarding bandwidth and number of users, enhancements of existing systems and introductions of conceptually new technologies and techniques have been researched and developed. Although new proposed technologies in theory provide increased network capacity, the backbone of a successful roll-out of a mobile telephone system is inevitably the planning of the network’s cellular structure. Hence, the fundamental aspect to a reliable cellular planning is the knowledge about the physical radio channel for wide sets of different propagation scenarios. Therefore, to study radio wave propagation in typical Australian environments, the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the Australian Telecommunications Cooperative Research Centre (ATcrc) in collaboration developed a cellular code division multiple access (CDMA) pilot scanner. The pilot scanner measurement equipment enables for radio wave propagation measurements in available commercial CDMA mobile radio networks, which in Australia are usually deployed for extensive rural areas. Over time, the collected measurement data has been used to characterise many different types of mobile radio environments and some of the results are presented in this thesis. The thesis is divided into an introduction section and four parts based on peer-reviewed international research publications. The introduction section presents the reader with some relevant background on channel and propagation modelling. Also, the CDMA scanner measurement system that was developed in parallel with the research results founding this thesis is presented. The first part presents work on the evaluation and development of the different revisions of the Recommendation ITU-R P.1546 point-to-area radio wave propagation prediction model. In particular, the modified application of the terrain clearance angle (TCA) and the calculation method of the effective antenna height are scrutinized. In the second part, the correlation between the smallscale fading characteristics, described by the Ricean K-factor, and the vegetation density in the vicinity of the mobile receiving antenna is investigated. The third part presents an artificial neural network (ANN) based technique incorporated to predict path loss in rural macrocell environments. Obtained results, such as prediction accuracy and training time, are presented for different sized ANNs and different training approaches. Finally, the fourth part proposes an extension of the path loss ANN enabling the model to also predict small-scale fading characteristics.

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Turyagyenda, Charles. "Energy efficient radio resource management for future mobile cellular radio access networks." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/6247/.

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Historically mobile Radio Access Networks (RANs) were optimised initially to maximise coverage and subsequently to improve capacity, user data rates and quality of service. However, the recent exponential growth in the volume of transmitted data coupled with the ever increasing energy costs has highlighted the need to optimise futuristic RANs from an energy efficiency perspective. This research study postulated the utilisation of radio resource management approaches to improve the energy efficiency of modern RANs, with a particular emphasis on the radio frequency energy performance. The research study yielded the following major outcomes. First, there was notable positive correlation between user channel quality improvements and the energy efficiency of RANs. Second, channel quality aware packet schedulers were more energy efficient than channel quality ignorant packet schedulers. Third, energy aware scheduling metrics coupled with power control algorithms can be utilised to optimise and refine the energy efficiency performance of the rate adaptive frequency domain packet scheduling. Fourth, the dynamic temporal and spatial traffic load characteristics, in the radio access network, present energy saving opportunities through collaborative and cooperative Inter-Cell Interference (ICI) management among neighbouring base stations. While the results presented in this thesis pertain to radio frequency and/or radio head energy consumption, the improved energy efficiency could be leveraged by increasing the inter site distance between base stations subsequently reducing the density of base stations in any given geographical area thus reducing the energy consumption of the RANs as a whole. The benefits of energy efficient RANs are twofold, i.e. reduction in the amount of CO2 emission and lower operating expenditure (OPEX).

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Arkhipov, Alexander. "IFDMA for uplink mobile radio communication systems." München Utz, 2010. http://deposit.d-nb.de/cgi-bin/dokserv?id=3440635&prov=M&dokv̲ar=1&doke̲xt=htm.

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Filiol, Norman M. "Sigma-delta modulation for FM mobile radio." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ37063.pdf.

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Rockliff, Simon C. "Frequency hopping techniques for digital mobile radio /." Title page, contents and abstract only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09phr683.pdf.

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Koshi, Virtyt. "Radio planning for future mobile communication networks." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390488.

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Pathak, Bhumin H. "Video transmission over UMTS mobile radio network." Thesis, Oxford Brookes University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432790.

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Muhson, Said A. "Digital data transmission over mobile radio channels." Thesis, Loughborough University, 1987. https://dspace.lboro.ac.uk/2134/10838.

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The aim of this work is to study data transmission over a microwave digital mobile radio channel at 900 MHz, where the channel is subjected to multipath fading. Besides the fading, the other impairments assumed here are additive noise, co-channel interference and adjacent channel interference. Two modulation techniques are investigated in this work, namely Quadrature-Amplitude-Modulation (QAM) and Quadrature-Phase-Shift- Keying (QPSK). The channel is characterised digitally, assuming multipath Rayleigh fading in the presence of noise. The detection process studied here are near-maximum likelihood schemes: non-linear equalisation methods are also considered in detail. The thesis is also concerned with carrier synchronisation and channel estimation under conditions of Rayleigh fading. Since the carrier syncn,honisation is a most important requirement in mobile radio, a Digital Phase Locked Loop (DPLL) technique has been designed and investigated in the form of a feedback digital synchronisation system. Two types of channel estimation technique, namely feedforward and feedback estimators, are also investigated in this work. The feedback estimator is modified by the addition of a digital control system, in order to reduce its delay, and to cope with rapidly fading signals. Successful carrier synchronisation is demonstrated by the use of space diversity. The study was completed using models of the component parts of the system, and by the use of extensive computer simulations to analyse the system under various operating conditions.

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Feeney, Thomas Michael. "The complex narrowband UHF mobile radio channel." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257146.

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An, Jone-Fang. "The implementation of mobile radio channel simulators." Thesis, University of Liverpool, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317868.

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Vargas, J. H. S. "Traffic performance of cellular mobile radio systems." Thesis, University of Essex, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383418.

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Ho, Philip Shiu Wai. "Structural intermodulation interference in mobile radio systems." Thesis, City University London, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305174.

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Ko, Yiu Fai. "Digital cellular mobile radio links and networks." Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280911.

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Turner, P. G. "Adaptive receivers for DS-CDMA mobile radio." Thesis, University of Bristol, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337258.

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GOMES, RENATO ARREGUI. "RADIO SIGNAL BEHAVIOUR ON MICROCELLULAR MOBILE ENVIRONMENTS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1999. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7473@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
Com o aumento da demanda pelos serviços celulares se faz necessário estudar e desenvolver técnicas cada vez mais sofisticadas para a melhoria da capacidade e da qualidade dos sistemas celulares. Uma destas é a utilização moderada de microcélulas em regiões urbanas, e em algumas situações em regiões suburbanas. Os maiores problemas da utilização de microcélulas são suas características de propagação, bem diferentes das características das células convencionais. Para melhor compreender as características de propagação de um sinal rádio móvel num ambiente microcelular, este trabalho se propôs a fazer um estudo experimental onde, fenômenos como forma de células, efeitos de sombreamento, multipercurso e outros, foram analisados. Um laboratório móvel foi montado e uma grande campanha de medidas foi realizada em ambientes urbanos de características diferentes. Análises determinísticas e estatísticas, foram realizadas para se determinar parâmetros como o fator de queda do sinal com a distância e o desvio padrão da variabilidade do sinal. Estes resultados são importantes para o cálculo aproximado da cobertura do sinal em regiões semelhantes às estudadas. Especial atenção foi dada ao cálculo do ponto de quebra da dependência do sinal com a distância. Este ponto define a transição entre a região de campo próximo e a região de difração, sendo fundamental para estudos de cobertura. Uma importante contribuição foi na determinação da dependência da cobertura do sinal com a altura da antena transmissora. Os resultados medidos ajudaram a caracterizar a célula e conseqüentemente obter informações para localizações ótimas das altura das antenas, além de definir a melhor cobertura que estas alturas podem oferecer. Uma análise estatística da variabilidade do sinal foi realizada e distribuições de probabilidade foram testados frente aos resultados experimentais. A determinação de parâmetros importantes destas distribuições ajudou na verificação da aderência destes modelos aos resultados medidos. Os resultados são de extrema importância para esclarecer aspectos de propagação do sinal em microcélulas e disponibilizar dados para a elaboração de modelos de predição para o cálculo da cobertura do sinal para o projetista, resultando numa melhoria da qualidade e da capacidade do sistema microcelular.
The ever-increasing demand for cellular services raises the necessity of developing more sophisticated techniques to improve system quality and capacity. One of the techniques is the use of microcells in urban and occasionally suburban regions. However, the major problems facing the microcell deployment are the microcells peculiar propagation characteristics, which are very different from the conventional cellular systems. In order to address this problem, an experimental study of cell shape, shadowing effects and multipath, was carried out. A mobile laboratory was assembled and extensive measurements on different urban environments were performed. Deterministic and statistical analysis were carried out to find the parameters such as path loss versus distance factor, and the standard deviation of signal variability. Special attention was given to the determination of the breaking point, transition between the near field and diffraction regions on line-of-sight path. An important contribution was on the study of the effects of transmitter antenna height on coverage. The measured results will help on cell characterization and on finding the best height for the base station antennas. A statistical analysis of signal variability was performed to determine the best-fit probability distribution function with parameters carefully calculated. The collected results are of extreme importance to clarify propagation aspects of microcellular signal and to make it available a huge data bank for elaboration of better prediction models which will produce better quality and capacity of the microcellular systems.

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Du, Toit Rene. "Mobile radio data network for documentation display." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51832.

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Thesis (MScEng)--University of Stellenbosch, 2000.
ENGLISH ABSTRACT: This product is designed as an educational tooL It was developed to make a classroom more organised. Better and easier communication between the teacher and the students can be established, as well as improved communication between different classrooms. The stand alone unit can be used anywhere because there is no wiring between this and the computer. It can be a big addition to the educational system, especially in places where books are not readily available for the students. The system consists of various components. These components are a computer, a stand alone unit and an interconnection for these two. The interconnection was incorporated with the use of radio links. At the computer side of the design, a windows interface was developed to enable the computer user to communicate with the stand alone unit user. The radio link was inserted to make the communication between the computer and the stand alone unit wireless. The stand alone unit consists of a keypad, liquid crystal display, serial port and a floppy drive. The serial port is used as connection between the stand alone unit and the radio links. It is possible to expand the system. The keypad can be replaced by a keyboard to enable the stand alone user to type and save data on the stand alone unit itself, and a hard drive might be added to increase the storage space. The inclusion of the floppy drive makes the system more compact and creates the possibility of transferring data by use of the floppy, which in tum does not limit a person to working only in one place.
AFRIKAANSE OPSOMMING: Hierdieproduk is ontwerp as 'n hulpmiddel vir die onderwys stelsel. Dit is ontwerp om 'n klaskamer meer georganiseerd te maak. Beter en makliker kommunikasie tussen onderwysers en studente word op hierdie manier verseker, asook verbeterde kommunikasie tussen verskillende klaskamers. Die alleenstaande eenheid kan enige plek gebruik word, aangesien daar geen bedrading is tussen die eenheid en die rekenaar nie. Dit kan 'n groot bydrae wees tot die onderwysstelsel, veral in plekke waar boeke nie so alledaags beskikbaar is nie. Die stelsel bestaan uit verskeie komponente. Hierdie komponente is 'n rekenaar, 'n alleenstaande eenheid en 'n verbinding tussen hierdie twee. Die verbinding tussen hierdie twee is met behulp van radio skakels gedoen. By die rekenaar kant van die ontwerp, is 'n rekenaar program geskryf wat die kommunikasie tussen die rekenaar en die alleenstaande eenheid beheer. Die radio skakel is ingesluit in die ontwerp om die kommunikasie tussen die rekenaar en die alleenstaande eenheid draadloos te hou. Die alleenstaande eenheid bestaan uit 'n miniatuur sleutelbord, vloeibare kristal vertoon, 'n serie poort en 'n slapskyf dryf. Die serie poort word gebruik as verbinding tussen die alleenstaande eenheid en die radio skakels. Dit is moontlik om die stelsel te vergroot. Die miniatuur sleutelbord kan vervang word deur 'n standaard sleutelbord om die alleenstaande eenheid gebruiker in staat te stelom data op die eenheid self te tik en te stoor. 'n Hardeskyf kan ook ingevoeg word om die stoor spasie van die stelsel te vergroot. Die insluiting van die slapskyf veroorsaak dat die stelsel meer kompak is en ontwikkel die moontlikheid om die data oor te dra met behulp van die skyf, wat weer 'n persoon in staat stelom op meer as slegs een plek te werk.

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Hoyle, Robert D. (Robert Douglas) Carleton University Dissertation Engineering Electrical. "Digital speech coding for land mobile radio." Ottawa, 1986.

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Filiol, Norman M. (Norman Maurice) Carleton University Dissertation Engineering Electronics. "Sigma-delta modulation for FM mobile radio." Ottawa, 1999.

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Mansell, Adrian Richard. "Linear transmitter design for flexible mobile transceivers." Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361137.

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Soltan, Othman A. "Efficiency improvements to the Groupe Special Mobile (GSM) digital mobile radio system." Thesis, Aston University, 1994. http://publications.aston.ac.uk/8060/.

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Groupe Spécial Mobile (GSM) has been developed as the pan-European second generation of digital mobile systems. GSM operates in the 900 MHz frequency band and employs digital technology instead of the analogue technology of its predecessors. Digital technology enables the GSM system to operate in much smaller zones in comparison with the analogue systems. The GSM system will offer greater roaming facilities to its subscribers, extended throughout the countries that have installed the system. The GSM system could be seen as a further enhancement to European integration. GSM has adopted a contention-based protocol for multipoint-to-point transmission. In particular, the slotted-ALOHA medium access protocol is used to coordinate the transmission of the channel request messages between the scattered mobile stations. Collision still happens when more than one mobile station having the same random reference number attempts to transmit on the same time-slot. In this research, a modified version of this protocol has been developed in order to reduce the number of collisions and hence increase the random access channel throughput compared to the existing protocol. The performance evaluation of the protocol has been carried out using simulation methods. Due to the growing demand for mobile radio telephony as well as for data services, optimal usage of the scarce availability radio spectrum is becoming increasingly important. In this research, a protocol has been developed whereby the number of transmitted information packets over the GSM system is increased without any additional increase of the allocated radio spectrum. Simulation results are presented to show the improvements achieved by the proposed protocol. Cellular mobile radio networks commonly respond to an increase in the service demand by using smaller coverage areas. As a result, the volume of the signalling exchanges increases. In this research, a proposal for interconnecting the various entitles of the mobile radio network over the future broadband networks based on the IEEE 802.6 Metropolitan Area Network (MAN) is outlined. Simulation results are presented to show the benefits achieved by interconnecting these entities over the broadband Networks.

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Moessner, K. "Reconfigurable mobile communication networks." Thesis, University of Surrey, 2001. http://epubs.surrey.ac.uk/844245/.

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Telecommunication technologies and networks are constantly changing; with the introduction of the GSM system the shift from wired to wireless telephony experienced a unique boom. Since then, behaviour and communication needs of users (i.e. subscribers) have undergone rapid changes from initially the need for pure wireless voice transmission to now data and multimedia content traffic. Introduction of the 3rd Generation (UMTS/IMT 2000) promised the delivery of these services and the integration with the Internet. However, legacy technologies and networks are not likely to be replaced soon, the different wireless and wired communication and information infrastructures will co-exist and will have to work, seemingly seamless, together. The here documented research work delivers basic mechanisms supporting this integration, therefore a variety of technologies from different areas, ranging from Software Radio technology to Object-Oriented computing, have been brought together to introduce reconfigurability to mobile communication networks. Distributed object computing technologies are evaluated and their application as signalling and support platforms for reconfigureable systems is shown in different examples. Other novelties are the introduction of a protocol for download of reconfiguration software, from various software sources, these sources include Smart Cards, wired outlets and Over-The-Air. Furthermore, an object-oriented framework for flexible, 'on-the-fly' protocol exchange has been developed; the mechanisms and architecture of this framework are described within this thesis. Combining protocol reconfiguration, software download and distributed platforms and focusing on control and management of reconfiguration have led to the design and definition of a reconfiguration management architecture. Functionality and structure of this architecture are documented, and its single modules are described. Providing means and mechanisms enabling management and control of reconfiguration within reconfigureable mobile communication networks is the purpose of this thesis. KM, Guildford, July 2001 Key words: reconfiguration, reconfiguration management. Software Radio, object-orientation, middleware, CORBA, Universal Control CHannel.

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Ekman, Torbjörn. "Prediction of Mobile Radio Channels : Modeling and Design." Doctoral thesis, Uppsala University, Signals and Systems Group, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2677.

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Prediction of the rapidly fading envelope of a mobile radio channel enables a number of capacity improving techniques like fast resource allocation and fast link adaptation. This thesis deals with linear prediction of the complex impulse response of a channel and unbiased quadratic prediction of the power. The design and performance of these predictors depend heavily on the correlation properties of the channel. Models for a channelwhere the multipath is caused by clusters of scatterers are studied. The correlation for the contribution from a cluster can be approximated as a damped complex sinusoid. A suitable model for the dynamics of the channel is an ARMA-process. This motivates the use of linear predictors.

A limiting factor in the prediction are the estimation errors on the observed channels. This estimation error, caused by measurement noise and time variation, is analyzed for a block based least squares algorithm which operates on a Jakes channel model. Efficient noise reduction on the estimated channel impulse responses can be obtained with Wienersmoothers that are based on simple models for the dynamics of the channel combined with estimates of the variance of the estimation error.

Power prediction that is based on the squared magnitude of linear prediction of the taps will be biased. Hence, a bias compensated power predictor is proposed and the optimal prediction coefficients are derived for the Rayleigh fading channel. The corresponding probability density functions for the predicted power are also derived. A performance evaluation of the prediction algorithm is carried out on measured broadband mobile radio channels. The performance is highly dependent on the variance of the estimation error and the dynamics of the individual taps.

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Ekman, Torbjörn. "Prediction of mobile radio channels : modeling and design /." Uppsala : Signals and systems [Signaler och system], Univ. [distributör], 2002. http://www.signal.uu.se/Publications/pdf/a023.pdf.

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Corvino, Virginia <1981&gt. "Radio resource management for pervasive mobile communication Networks." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/2200/.

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Kotsopoulos, S. A. "Frequency planning techniques for cellular mobile radio systems." Thesis, University of Bradford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332176.

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Hu, Y. F. "Intermodulation interference probabilities in cellular mobile radio systems." Thesis, University of Bradford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380394.

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Hammuda, Husni. "Spectral efficiency of cellular land mobile radio systems." Thesis, University of Bristol, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279698.

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MACEDO, JANAINA FERREIRA. "SPACE-TIME CHARACTERIZATION OF THE MOBILE RADIO CHANNEL." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2003. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=3521@1.

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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Este trabalho apresenta os resultados da investigação da utilização da Técnica de Sondagem em Frequência na estimação de dispersividade Espaço-Temporal do Canal Rádio Móvel. Modifcações na técnica clássica de varredura em frequência foram implementadas: um conjunto de antenas denominado array foi construído e calibrado e um algoritmo de pós-processamento do sinal medido foi testado. Foi realizada uma campanha de medidas em três ambientes diferentes para averiguar a aplicabilidade do conjunto. Foram obtidos bons resultados, demonstrando a efciência da metodologia de medidas aplicada.
This work presents the results of an investigation of the use of the Frequency Sounding technique in Mobile Radio Channel`s Space-Time Dispersion characterization. Hence, some changes in the classical Frequency Sounding Technique were employed: a set of antennas was built and calibrated and an algorithm for signal pos processing was tested. A measurement campaign was carried out on three different environments to test the applicability of the set as a whole. Very good results showed the efficiency of the measurements methodology applied.

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Rahmani-Shirazi, Ashiyan Ian. "Gender Praxis| Rural Fiji Radio and Mobile Devices." Thesis, University of Hawai'i at Manoa, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13422469.

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This communications study looks at gender-based self-reflexive theoretically guided practice, “praxis,” to explore the way in which a women's community media organization, femLINKpacific, pursues its goals of enhancing women's participation in governance structures and resiliency to extreme weather conditions. This study contributes to the nascent literature on mobile device and radio interaction by exploring the way in which women in rural Fiji utilize mobile devices to interact with femTALK, the community radio station of femLINKpacific. The study is based on the theoretical frameworks of inclusive innovation, post-development theory, and participatory communications theory in the context of gender-based ICT4D. Two main platforms, Mobile Suitcase Radio (MSR), a portable radio platform, and Women’s Weather Watch (WWW), a mobile-phone based weather reporting network, and an additional non-mediated communication venue of monthly women’s gatherings were explored through a 3-phase study, utilizing interviews and focus groups, with radio station staff and women leader’s networks.

Main findings included the role of WWW to transmit information for preparedness for Tropical Cyclone Winston, and indigenous food practices shared through the various platforms, as well as the role of MSR, when used in conjunction with the issues shared at the monthly consultations, to bring greater awareness to the women’s “voice.” This study extends to understanding the role of mutually supportive, systematic processes to enhance women's participation in governance structures, including the role and effectiveness of inter-ethnic groups in addressing community issues, and capacity building through incremental acclimatizing activities.

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Cohen, Alain Jerome. "Simulating virtual circuits in mobile packet radio networks." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/14904.

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Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1986.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
Bibliography: leaf 39.
by Alain Jerome Cohen.
B.S.

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Schmier, Robert Gordon. "Fade durations in satellite-path mobile radio propagation." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/91053.

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Fades on satellite to land mobile radio links are caused by several factors, the most important of which are multipath propagation and vegetative shadowing. Designers of vehicular satellite communications systems require information about the statistics of fade durations in order to overcome or compensate for the fades. Except for a few limiting cases, only the mean fade duration can be determined analytically, and all other statistics must be obtained experimentally or via simulation. This report describes and presents results from a computer program developed at Virginia Tech to simulate satellite path propagation of a mobile station in a rural area. The simulator was developed using 869 MHz balloon data provided by Wolfhard Vogel of the University of Texas at Austin and was tested using helicopter data provided by Wolfhard Vogel and Julius Goldhirsh of the Johns Hopkins University Applied Physics Laboratory. It generates rapidly-fading and slowly-fading signals by separate processes that yield correct cumulative signal distributions and then combines these to simulate the overall signal. This is then analyzed to yield the statistics of fade durations.
M.S.

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Dissertations / Theses on the topic 'Mobile radio'

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