" In telecommunications, a cooperative scheme refers to a method where two or more users share or combine their information in order to increase diversity gain or power gain. In contrast to conventional point-to-point communications, cooperative communications allow different users in a wireless network to share resources so that instead of maximizing the performance of its own link, each user collaborates with its neighbours to achieve an overall improvement in performance. In this dissertation, we consider different models for transmission and reception and explore cooperative techniques that increase the reliability and capacity gains in wireless networks, with consideration to practical issues such as channel estimation errors and backhaul constraints. This dissertation considers the design and performance of cooperative communication techniques. Particularly, the first part of this dissertation focuses on the performance comparison between interference alignment and opportunistic transmission for a 3-user single-input single- output (SISO) interference channel in terms of average sum rate in the presence of channel estimation errors. In the case of interference alignment, channel estimation errors cause interference leakage which consequently results in a loss of achievable rate. In the case of opportunistic transmission, channel estimation errors result in a non-zero probability of incorrectly choosing the node with the best channel. The effect of these impairments is quantified in terms of the achievable average sum rate of these transmission techniques. Analysis and numerical examples show that SISO interference alignment can achieve better average sum rate with good channel estimates and at high SNR whereas opportunistic transmission provides better performance at low SNR and/or when the channel estimates are poor. We next considers the problem of jointly decoding binary phase shift keyed (BPSK) messages from a single distant transmitter to a cooperative receive cluster connected by a local area network (LAN). An approximate distributed receive beamforming algorithm is proposed based on the exchange of coarsely- quantized observations among some or all of the nodes in the receive cluster. By taking into account the differences in channel quality across the receive cluster, the quantized information from other nodes in the receive cluster can be appropriately combined with locally unquantized information to form an approximation of the ideal receive beamformer decision statistic. The LAN throughput requirements of this technique are derived as a function of the number of participating nodes in the receive cluster, the forward link code rate, and the quantization parameters. Using information-theoretic analysis and simulations of an LDPC coded system in fading channels, numerical results show that the performance penalty (in terms of outage probability and block error rate) due to coarse quantization is small in the low SNR regimes enabled by cooperative distributed reception. An upper/lower bound approximation is derived based on a circle approximation in the channel magnitude domain which provides a pretty fast way to compute the outage probability performance for a system with arbitrary number of receivers at a given SNR. In the final part of this dissertation, we discuss the distributed reception technique with higher- order modulation schemes in the forward link. The extension from BPSK to QPSK is straightforward and is studied in the second part of this dissertation. The extension to 8PSK, 4PAM and 16QAM forward links, however, is not trivial. For 8PSK, two techniques are proposed: pseudobeamforming and 3-bit belief combining where the first one is intuitive and turns out to be suboptimal,the latter is optimal in terms of outage probability performance. The idea of belief combining can be applied to the 4PAM and 16QAM and it is shown that better/finer quantizer design can further improve the block error rate performance. Information-theoretic analysis and numerical results are provided to show that significant reliability and SNR gains can be achieved by using the proposed schemes. "

Abstract This research mainly combines: Police policy, transportation, fire control, news, and public affairs. - Use Kaohsiung Wireless platform as a starting point. - PWLAN technology will become the mainstream for the strategic integrated platform. - M-City is able to change people¡¦s original life style; increase life¡¦s mobility and conveniences. - The government wants to develop a wireless service platform in order to promote development of a mobile city. Kaohsiung City Wireless shared platform has three aspects: technology, public service and marketing. This research uses two ways to gather related data. 1. Key interview: interviewing professional scholars. 2. Conducting Survey: internet users are the target. - To analyze how to attract citizens to use related policies in order to promote the development of wireless industry. - To expect a fast development with a positive cycle, and upgradethe city¡¦s competitiveness. Conclusion is divided into five parts: 1. Conclusion and basic information from the replied surveys 2. descriptive statistics 3. interceptive analysis 4. elements analysis reports in depth The conclusion has discovered, Regarding to the technological aspect, people will consider three elements when they choose to use wireless internet: the maturity of the wireless technology, the dissemination of wireless internet and the creation of the needs of wireless internet. Aspect of public service: 1. Information related to location 2. Information related to prevention of disasters 3. Involvement of residents 4. Police and Fireman¡¦s Priority 5. Residents hope: Government can prevent crimes or salve disasters by the construction of wireless internet. In the aspect of marketing: Citizens wish to receive different information through wireless internet.

This dissertation introduces new and simple techniques for suppression of multispurious passbands, which are inherent to the conventional microstrip parallel coupleline bandpass filters. In addition, the operation of harmonic suppression is analyzed using a simple model. Special emphasis is placed on the applications of several new filter designs for microstrip diplexers and multiplexers. Compact, full-duplex beam scanning antenna transceiver systems with extremely broad bandwidth have also been developed. Recent advances in broadband monolithic microwave integrated circuit (MMIC) amplifiers make the realization of extremely broadband phased-array transceiver systems possible. The ultra-wideband phased-array transceiver systems can be used in multi-band mobile satellite communication systems and wideband radars. This dissertation presents a multi-band, compact, full-duplex, beam scanning antenna transceiver system for satellite communications and two designs of ultra-wideband, low-cost radar systems as applications of the MMIC amplifiers. In addition, a multi-frequency antenna has been developed. A single-feed triple frequency microstrip patch antenna is presented as an answer to the recent demand for multi-function systems in the wireless communications. In summary, the research presented in this dissertation covers every component required to build an ultra-wideband, full-duplex beam scanning phased-array antenna transceiver. The work done in this dissertation should have many applications in the wireless communication systems and wideband radar technologies.

Following the successful launch of CP3 and CP4, the PolySat team noticed an unreliable uplink to both satellites. A significant problem with the PolySat COMM system is poor receive sensitivity of the communications system. Efforts have been made to improve the uplink margin, but without proper characterization of the receiver sensitivity, the problem cannot be fully addressed. By developing an accurate method of measuring receive sensitivity, a methodical approach can be used to properly diagnose the communication system and link budget. Two revisions of the PolySat COMM system will be measured and compared. An in-depth study of the PolySat COMM system will be performed, providing an interesting look at possible causes of the inconsistent uplink and methods of improving the COMM system. For future bus development, this test setup can be used to accurately measure the receive sensitivity.

ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / Design, development, fabrication, and deployment of an austere, deployable telemetry (TM) system, in only 3 1/2 weeks, will be discussed. This austere approach will be compared to a standard approach. TM candidate systems will be discussed along with exigencies and limitations (test geometry, link analysis, multiple test areas, schedule, cost, fabrication ...) that shaped their selection. Utilization of existing Radio Frequency (RF) systems in "unintended" applications will be discussed. System setup and BER testing with a simulated 'aircraft' will be presented, including observed multipath effects during testing, versus actual performance. Finally, benefits and test efficiencies garnered by having vehicle TM, real- time TM acquisition, processing and display, while deployed to a test area with no range instrumentation, will be presented.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / In this paper, we propose applying the spatio-temporal signal processing and OFDM techniques to a multiple-antenna system in order to achieve high data rate and high performance transmission capability. In order to perform real time processing for this system, we also propose a complexity reduced QR beamforming algorithm. The performance of the proposed system has been investigated for a two-ray frequency-selective fading model by extensive computer simulations. These results show that significant benefits can be realized in terms of lower bit error rate and higher data transmission rate.

<p>In Sweden we come in contact with the English language almost daily; in television shows, radio commercials and at work. English is also mandatory in the Swedish curriculum; therefore it is important that the students learn as much as possible in school, to be able to use English in their daily life. Teachers use different methods to help students acquire the tools needed to learn English, or any other subject for that matter. One method is oral feedback, which is used to immediately encourage students or correct them when making an error. My aim in this study is therefore to investigate if students find oral feedback in the classroom valuable and if not, how they would like it to be changed. To investigate this I handed out a questionnaire to five classes. The questions were divided up into three categories: if the students had noticed oral feedback being given to them, what their experiences of oral feedback were and how they would like the feedback to be delivered. I also made observations and recorded three classes. The results of this investigation showed that the students were positive to oral feedback in the classroom. Most of the students had noticed oral feedback being given to them, and the teachers had mostly corrected the students’ grammar and pronunciation. These were also the areas where the students felt they had developed the most from oral feedback. In the questionnaire the students pointed out that they wanted the feedback to be delivered privately and that the teachers have to be careful how they give the feedback, they have to always remember to give positive feedback as well as corrective feedback.</p>

<p>Detta arbete bygger på en studieresa, under en månads tid, till Indien, Dharamsala. Dharamsa-la är känd för att inhysa den tibetanska statens exilregering och inte minst den tibetanska bud-dismens andlige ledare Dalai Lama. Därav är Dharamsala en viktig tillflyktsort för de tibe-tanska flyktingar som undkommit den Kinesiska regeringens förtryck i Tibet.</p><p>Syftet med denna studie blir därför, att få mer insikt och kunskap om hur man idag i Dha-ramsala bemöter tibetanska flyktingbarn från Tibet.</p><p>Jag fick äran, att möta 8 av de människor som dagligen möter och arbetar med tibetanska flyktingbarn på ett eller annat sätt.</p><p>I undersökningen har jag dels använt mig av kvalitativa intervjuer och dels av observatio-ner. Genom dessa metoder framgår det, att tibetanska flyktingbarn blir bemötta på ett kärleks-fullt och respektfullt sätt. Detta för, att de skall få ett värdigt liv i frihet samt en gedigen ut-bildning.</p><p>Tibetanernas omtanke och kärlek till sin nästa generation motiverar barnen, i Dharamsala, att vilja studera, för att senare i livet ska kunna hjälpa andra tibetaner i nöd, vilka fortfarande är under den Kinesiska regeringens våld i Tibet.</p> / <p>This paper is a result of a one month field study Dharamsala in India. Dharamsala is well-known for harbouring the exile Tibetan government and also their religious leader in Tibetan Buddhism, Dalai Lama. Because of this Dharamsala is an important sanctuary fore Tibetan refugees who are escaping from the Chinese government’s oppression in Tibet.</p><p>The purpose of this study is therefore to get a better insight and knowledge how people today in Dharamsala receive Tibetan refugee children from Tibet.</p><p>I got the privilege to meet 8 of the people who, in one way or another, daily meet and work with Tibetan refugee children.</p><p>In this study I have used the methods qualitative interview and observation. Through these methods it’s clear that, Tibetan refugee children are received with love and respect in Dhar-amsala. In this way the Tibetan refugee children got a worthy life in freedom and a proper education.</p><p>The love and compassion from the Tibetan people in Dharamsala, to their next generation, motivate these children to study hard so that they later in life can help other Tibetans who still live under the Chinese government’s oppression in Tibet.</p>

The aim of Sweden’s refugee settlement policy is that refugees should be offered an             initial place of dwelling in a municipality with available accommodation and a good             labour market within commuting distance. Refugees risk long-run unemployment, if             initially placed in a municipality with bad labour market opportunities (see Edin et             al., 2004 and Åslund et al., 2006). It is therefore important to know to what extent             the state of a municipality’s labour market (and not only availability of apartments)             drives the willingness to receive refugees. No such study has previously been con-             ducted. This paper thus aims to bridge this gap in the research by analyzing data             between 2006-2010 for all 290 Swedish municipalities and their contracts with the             Swedish central government regarding refugee reception. The main findings are,             when accounting for municipality-fixed effects, that neither unemployment nor             available apartments affect the probability of signing a contract. Additional govern-             ment grants, on the other hand, has a positive effect on the likelihood of signing a             contract. Among municipalities which do sign contracts, the agreed number of refu-             gees is negatively affected by higher municipality unemployment and positively             affected by additional available apartments.

Detta arbete bygger på en studieresa, under en månads tid, till Indien, Dharamsala. Dharamsa-la är känd för att inhysa den tibetanska statens exilregering och inte minst den tibetanska bud-dismens andlige ledare Dalai Lama. Därav är Dharamsala en viktig tillflyktsort för de tibe-tanska flyktingar som undkommit den Kinesiska regeringens förtryck i Tibet. Syftet med denna studie blir därför, att få mer insikt och kunskap om hur man idag i Dha-ramsala bemöter tibetanska flyktingbarn från Tibet. Jag fick äran, att möta 8 av de människor som dagligen möter och arbetar med tibetanska flyktingbarn på ett eller annat sätt. I undersökningen har jag dels använt mig av kvalitativa intervjuer och dels av observatio-ner. Genom dessa metoder framgår det, att tibetanska flyktingbarn blir bemötta på ett kärleks-fullt och respektfullt sätt. Detta för, att de skall få ett värdigt liv i frihet samt en gedigen ut-bildning. Tibetanernas omtanke och kärlek till sin nästa generation motiverar barnen, i Dharamsala, att vilja studera, för att senare i livet ska kunna hjälpa andra tibetaner i nöd, vilka fortfarande är under den Kinesiska regeringens våld i Tibet. / This paper is a result of a one month field study Dharamsala in India. Dharamsala is well-known for harbouring the exile Tibetan government and also their religious leader in Tibetan Buddhism, Dalai Lama. Because of this Dharamsala is an important sanctuary fore Tibetan refugees who are escaping from the Chinese government’s oppression in Tibet. The purpose of this study is therefore to get a better insight and knowledge how people today in Dharamsala receive Tibetan refugee children from Tibet. I got the privilege to meet 8 of the people who, in one way or another, daily meet and work with Tibetan refugee children. In this study I have used the methods qualitative interview and observation. Through these methods it’s clear that, Tibetan refugee children are received with love and respect in Dhar-amsala. In this way the Tibetan refugee children got a worthy life in freedom and a proper education. The love and compassion from the Tibetan people in Dharamsala, to their next generation, motivate these children to study hard so that they later in life can help other Tibetans who still live under the Chinese government’s oppression in Tibet.