This thesis examines the sampling and jitter specifications and considerations for Global Navigation Satellite Systems (GNSS) software receivers. Software Radio (SWR) technologies are being used in the implementation of communication receivers in general and GNSS receivers in particular. With the advent of new GPS signals, and a range of new Galileo and GLONASS signals soon becoming available, GNSS is an application where SWR and software-defined radio (SDR) are likely to have an impact. The sampling process is critical for SWR receivers where it occurs as close to the antenna as possible. One way to achieve this is by BandPass Sampling (BPS), which is an undersampling technique that exploits aliasing to perform downconversion. In this thesis, the allowable sampling frequencies are calculated and analyzed for the multiple frequency BPS software radio GNSS receivers. The SNR degradation due to jitter is calculated and the required jitter standard deviation allowable for wach GNSS band of interest is evaluated and a basic jitter budget is calculated that could assist in the design of multiple frequency SWR GNSS receivers. Analysis shows that psec-level jitter specifications are required in order to keep jitter noise well below the thermal noise for software radio satellite navigation receivers. However, analysis of a BPSK system shows that large errors occur if the jittered sample crosses a data bit boundary. However, the signal processing techniques required to process the BOC modulation are much more challenging than those for traditional BPSK. BOC and AltBOC have more transitions per chip of spreading code and hence jitter creates greater SNR degradation. This work derives expressions for noise due to jitter taking into account the transition probability in QPSK, BOC, AltBOC systems. Both simulations and analysis are used to give a better understanding of jitter effects on Software Radio GNSS receivers.

No description available.

Thesis (M.S.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 2004. / Includes bibliographical references (p. 71-72).

This thesis deals primarily with the problem of soft-error tolerance in digital machines. The possible sources of soft errors are reviewed. It is shown that the significance of ionizing radiation increases with the scaling down of MOS technologies. The characteristics of electromagnetic interference sources are also discussed. After presenting the conventional methods of dealing with soft errors, a new approach to this problem is suggested. The new approach, called Soft-Error Filtering (SEF), consists of filtering every output of the logic before latching it, in such a way that a transient injected into a machine does not change the final result of an operation. An analysis of the reduction in the error rate that is obtained by using SEF is presented. For example, this analysis demonstrates that the error rate due to alpha particles generated by the decay of radioactive elements becomes negligible. A great deal of attention is devoted to the design of filtering latches which is an essential component for implementing SEF machines. Three structures are considered and a CMOS implementation is proposed in each case. The double-filter latch is the best of the three implementations. It features a nearly optimum performance in the time domain and it is relatively insensitive to process fluctuations. An overhead analysis demonstrates that SEF usually results in a small overhead, both in area and in time simultaneously. In conclusion, SEF is the best approach to the problem of designing a machine tolerant to short transients.

Information and communication technologies (ICTs) have, in the recent past, attracted enormous attention as important tools for socio-economic development. However, the role of ICTs in fostering development and addressing the needs of the poor, especially in developing countries, has become the subject of a heated debate. This contestation is due to the high failure rate of the ICTs for development projects and a widening gap between the expectations of what ICTs can possibly do and the experiential reality of how these technologies are actually being used. More often than not ICTs have been regarded as a panacea or a „magic bullet‟ that will solve all development problems, with ill-conceived expectations of how they would be used. This study examined the relationship between ICTs and sustainable livelihoods in selected rural areas of Tanzania. The aim was to investigate how and for what purposes ICTs are used by people in the selected rural areas of Tanzania and to study the effect that ICTs have had on the various aspects of their livelihoods. A combination of the sustainable livelihoods framework and other ICTs for development models formed the theoretical foundation of the study. The investigation was carried out using ICT services provided by the telecentres and mobile phone services. The study was conducted in four rural districts in Tanzania which have telecentres. It used a multi-case study research design. A mixed paradigm methodology was adopted and the qualitative research was used as a dominant paradigm. Data was collected through structured interview protocols administered to 203 users and non-users of ICTs in communities surrounding the telecentres. Semi-structured interview protocols were administered to four managers of the telecentres. In addition, eight focus group discussions were conducted in communities surrounding the telecentres. An observation checklist was used to verify data obtained from managers, users and non-users of the telecentres. The study administered semi-structured interview protocols to officers from the ministry responsible for ICTs in Tanzania, that is the Ministry of Infrastructure Development (MoID), The Tanzania Communication and Regulatory Authority (TCRA) and a national research institution (The Commission for Science and Technology- COSTECH). The findings of the study indicated that, contrary to the use of mobile phones, which was characterised by greater uniformity across socio-economic groups and gender, telecentre users in the researched areas were generally young. The majority were males with higher levels of education. It was found that telecentres management have failed to take into consideration the appalling conditions of the extremely poor and disadvantaged individuals in their provision of ICT services to the community. The study established that the urban rural digital divide still exists and is still a reality in the areas reviewed, despite some efforts that are under way to bring ICTs to those communities. Old ICTs such as radio and television are not universally available. It was observed that inadequate road infrastructure makes it difficult for farmers to transport their produce to markets outside the districts, even in cases where farmers are provided with information on the availability of those markets. Inadequate electricity supply hinders large-scale uptake of ICTs in rural areas. The findings show that telecentres managers were not aware of the information needs of the communities they serve and therefore they were not in a position to meet such information needs. Due to personnel‟s inadequate skills and capacity the Ministry of Infrastructure Development did not play its policy-making function effectively. This problem, coupled with delayed implementation of important policy objectives such as the universal access policy and even the national ICT policy itself, affects the development of the ICT sector in rural areas of Tanzania. The findings further show that while the necessary conditions for access exist in all the telecentres involved in the study, sufficient conditions for access are still lacking, especially with regard to skills, awareness and affordability. On the relationship between ICT and rural livelihoods the findings of the study show that while ICTs may not fully support and sustain socio-economic development in poor communities, the impact of these technologies extends to various aspects of the livelihoods of the rural people. Economically, these technologies lead to better earnings and savings. Socially, they help in community interaction and knowledge-sharing, better follow-up for remittances and creation of savings and credit co-operative societies. In relation to human capital, the technologies‟ implications extend to ICT literacy, improved farming techniques and better access to information on new cash crops. The use of ICTs in rural areas is still faced with many barriers. These range from affordability to language problems and the lack of basic infrastructure such as electricity. Language was particularly found to be a substantial barrier to effective use and application of ICTs. The study recommends that telecentre managers should re-design programmes with the aim of bringing the under-represented groups such as farmers back to the centre of their projects, rather than treating them as passive receivers of ICT services. On the issue of mobile phones, there is a need to develop services that are nuanced towards the real needs of the rural people and incorporate them into the mobile technology. The study recommends that universal access policies should involve old ICTs such as radio and television, or people in the rural areas, who have fewer resources, will eventually pay too much for basic communication services, as in the case of satellite television and radio. Capacity-building is important, not only in the regulatory authorities, but also in the ministries responsible for ICTs and other institutions involved with ICTs, so as to provide effective national ICT leadership. The study recommends that managers of telecentres learn about the different aspects of access, in order for them to go beyond the provision of physical access to ICTs. Continuous improvement and renewal of telecentre services is necessary to ensure survival of the telecentres. Collaboration of the telecentres and other organisations, such as academic institutions, is needed to create content both for the telecentres and the community radios. Telecentres and other information systems developed or adopted to serve the people must meet the needs of the people intended to be served. This can be done by regularly conducting information needs assessment. / Thesis (Doctor of Phil. (Information Studies)) - University of KwaZulu-Natal, Pietermaritzburg, 2008.

No description available.

This thesis examines the sampling and jitter specifications and considerations for Global Navigation Satellite Systems (GNSS) software receivers. Software Radio (SWR) technologies are being used in the implementation of communication receivers in general and GNSS receivers in particular. With the advent of new GPS signals, and a range of new Galileo and GLONASS signals soon becoming available, GNSS is an application where SWR and software-defined radio (SDR) are likely to have an impact. The sampling process is critical for SWR receivers where it occurs as close to the antenna as possible. One way to achieve this is by BandPass Sampling (BPS), which is an undersampling technique that exploits aliasing to perform downconversion. In this thesis, the allowable sampling frequencies are calculated and analyzed for the multiple frequency BPS software radio GNSS receivers. The SNR degradation due to jitter is calculated and the required jitter standard deviation allowable for wach GNSS band of interest is evaluated and a basic jitter budget is calculated that could assist in the design of multiple frequency SWR GNSS receivers. Analysis shows that psec-level jitter specifications are required in order to keep jitter noise well below the thermal noise for software radio satellite navigation receivers. However, analysis of a BPSK system shows that large errors occur if the jittered sample crosses a data bit boundary. However, the signal processing techniques required to process the BOC modulation are much more challenging than those for traditional BPSK. BOC and AltBOC have more transitions per chip of spreading code and hence jitter creates greater SNR degradation. This work derives expressions for noise due to jitter taking into account the transition probability in QPSK, BOC, AltBOC systems. Both simulations and analysis are used to give a better understanding of jitter effects on Software Radio GNSS receivers.

Thesis (Ph.D)--Computing, Georgia Institute of Technology, 2009. / Committee Chair: Palem, Krishna V.; Committee Member: Lim, Sung Kyu; Committee Member: Loh, Gabriel H.; Committee Member: Mudge, Trevor; Committee Member: Yalamanchili, Sudhakar. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Les travaux de cette thèse s'intéressent aux problèmes de performance et de coût des architectures MPSoC à base de NoC, en tirant parti des possibilités offertes par les technologies d'intégration 3D. Plusieurs contributions originales sont proposées. Tout d'abord, une étude approfondie à propos des différentes granularités de partitionnement au sein des circuits 3D est réalisée. En se basant sur cette analyse, ce travail de thèse est orienté aux architectures 3D partitionnées au niveau des blocs macroscopiques. Ainsi, la contribution de l'intégration 3D est limitée aux interconnexions verticales inter-blocs. Afin d'améliorer les performances de ces interconnexions, une topologie hiérarchique de NoC est proposée pour diminuer la latence et augmenter le débit des communications au sein des architectures 3D partitionnées au niveau des macro-blocs. D'autre part, un modèle au niveau du système est présenté pour évaluer et comparer les coûts des différentes options technologiques de l'intégration 3D. Partant de cette évaluation, nous proposons une architecture multiprocesseur reconfigurable empilable pour les applications de télécommunication 4G, en tenant compte des problèmes de coût. / This PhD research is intended to deal with cost and performance issues of NoC-based MPSoC architectures by taking advantage of the opportunities offered by 3D integration technologies. Several original contributions are proposed. First, a deep investigation of the different partitioning granularities within 3D circuits is performed. Based on this analysis, this PhD work is oriented to focus on core-level partitioned 3D architectures, and then to restrict the contribution of 3D stacking to the global inter-block vertical interconnections. To enhance the performance of global interconnect architectures, a hierarchical NoC topology is proposed to improve communication latency and throughput within core-partitioned 3D architectures. On the other hand, a system-level cost analysis model is presented to assess and compare several 3D integration technology options. Based on this evaluation, we propose a cost-aware stackable reconfigurable multiprocessor NoC-based architecture to address the requirement of 4G telecom applications.

This thesis investigates the feasibility of using existing IP-based control and monitoring protocols within professional audio installations utilising IEEE 1394 technology. Current control and monitoring technologies are examined, and the characteristics common to all are extracted and compiled into an object model. This model forms the foundation for a set of evaluation criteria against which current and future control and monitoring protocols may be measured. Protocols considered include AV/C, MIDI, QSC-24, and those utilised within the UPnP architecture. As QSC-24 and the UPnP architecture are IP-based, the facilities required to transport IP datagrams over the IEEE 1394 bus are investigated and implemented. Example QSC-24 and UPnP architecture implementations are described, which permit the control and monitoring of audio devices over the IEEE 1394 network using these IP-based technologies. The way forward for the control and monitoring of professional audio devices within installations is considered, and recommendations are provided. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in