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Дисертації з теми "Wireless transmission systems"

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Автор: Grafiati

Опубліковано: 6 вересня 2023

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1

Ganti, Anand 1975. "Transmission scheduling for wireless and satellite systems." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29316.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003.
Includes bibliographical references (p. 135-137).
We study queuing systems with time-varying service rates, as a natural model of satellite and wireless communication systems. Packets arrive at a satellite to be transmitted to one of the sub-regions (channels) in a service area. The packets are stored in an on-board buffer and in a separate queue for each channel. The satellite has a limited power available for scheduling transmissions, and a fixed number of transmitters. The power allocated to a particular channel, in conjunction with the channel state, determines the transmission rate of the channel, i.e., the service rate for the queue corresponding to that channel. The assignment of transmitters to the queues as well as the power allocated to each transmitter are modeled as control variables. The goal is to design a power allocation policy so that the expected queue size, in steady-state, is minimized. We model the system as a slotted system with N queues, and i.i.d. Bernoulli arrivals at each queue during each slot. Each queue is associated with a channel that changes between "on" and "off" states according to i.i.d. Bernoulli processes. We assume that the system has K identical transmitters ("servers").
(cont.) Each server, during each slot, can transmit up to Co packets from a queue associated with an "on" channel. We show that when K and Co are arbitrary and a total of up to KCo packets can be served from all the N queues in a time slot, a policy that assigns the K servers to the "on" channels associated with the K longest queues is optimal. We also consider a "fluid" service model under which fractional packets can be served, for the case K = N, and subject to a constraint that at most C packets can be served in total over all of the N queues. We show that there is an optimal policy which serves the queues so that the resulting vector of queue lengths is "Most Balanced." We also describe techniques to upper bound the expected queue size in steady-state under an optimal policy.
by Anand Ganti.
Ph.D.

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2

Chu, Li Electrical Engineering &amp Telecommunications Faculty of Engineering UNSW. "Space-time coded transmission schemes on wireless channels." Awarded by:University of New South Wales. Electrical Engineering & Telecommunications, 2007. http://handle.unsw.edu.au/1959.4/40880.

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Highly reliable and fast wireless communication services demand the communication channel capacity to be fully exploited. Vast amount of research effort have been expanded in the development of advance technologies, such as signal processing, channel coding, modulation/demodulation, diversity techniques, and so on. This thesis focuses on the development of space-time coded transmission schemes. In order to provide high diversity gain with minimum design complexity, we propose a closed-loop beamforming transmission technology combined with existing simple channel coding method. We show that this coded beamforming scheme can achieve full diversity as the space-time coding technique does for a multiple-antenna system, while significantly reducing the design complexity. It is normally impractical to install multiple antennas on a small wireless communication device. We therefore further our research to cooperative communication, in which single-antenna communicators share their antennas with partners in information relay, so that the benefit of multiple-antenna transmission can be achieved for the singleantenna users. We analyze the system performance for the typical decode-and-forward user cooperative system, formulate the code design criteria, and construct optimal codes. To simplify the system design, we introduce estimate-and-forward protocol with differential modulation scheme. In order to ensure the practicality of the system design, we introduce an equivalent link model to replace the source-relay-destination link, taking into account the imperfect detections at the relay. Finally we extend the analysis to a multiple-relay system using selective combiner at the destination.

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3

Yow, Thiam Poh. "Tunneled data transmission over wireless sensor networks." Thesis, Monterey, Calif. : Naval Postgraduate School, 2007. http://bosun.nps.edu/uhtbin/hyperion-image.exe/07Dec%5FYow.pdf.

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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2007.
Thesis Advisor(s): McEachen, John C. ; Tummala, Murali. "December 2007." Description based on title screen as viewed on January 24, 2008. Includes bibliographical references (p. 73-74). Also available in print.

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4

Yu, Yuehua. "Non-Orthogonal Transmission for Future Wireless Communication Systems." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/18172.

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The 5G networks are envisioned to support large data traffic, massive connectivity, and ultra low-latency communications. This thesis focuses on the low-complexity design and performance analysis of non-orthogonal transmissions, which is one of the potential candidates to address the aforementioned challenges. We first develop a low-complexity transceiver design for massive MIMO channels. By exploring a sparse representation of the MIMO channel in the virtual angular domain, we generate a set of transmit-receive beam pairs to support the transmission of multiple data streams. These data streams can be easily separated via SIC, and the power allocation is optimized with water-filling. The near-optimal DoF and capacity achieved by the proposed approach are analysed. Next, we investigate the joint antenna selection (AS) problem for MIMO TWRNs. Two near-optimal algorithms, namely the joint relay-source AS (JRSAS) and the separated relay-source AS (SRSAS), are proposed in a greedy manner. Numerical results show that both JRSAS and SRSAS can approach the optimal AS algorithm but with much lower computational complexity. Subsequently, we extend the joint AS problem to a MIMO NOMA system. For the rate-adaptive NOMA, the throughput-oriented AS algorithms are first proposed. For the fixed-rate NOMA, the outage-oriented AS approaches are then developed. The average capacity and outage performance of the proposed algorithms are analysed and compared to the OMA counterparts. By naturally integrating the short-packet and NOMA techniques, we finally investigate the potential ability of short-packet communications using NOMA to fulfil low-latency transmission. For a given set of reliability constraints of users, the transmission latency of a fundamental two-user model is first studied, which is followed by a more practical multi-user system. Numerical results demonstrate the superior performance of NOMA in reducing physical-layer transmission latency in short-packet communications.

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5

Wu, Min. "Multimedia data transmission for mobile wireless applications." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4132.

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Анотація:

Thesis (Ph. D.)--University of Missouri-Columbia, 2005.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (November 14, 2006) Vita. Includes bibliographical references.

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6

Dani, Janak. "Transmission distortion modeling for wireless video communication." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/5845.

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Анотація:

Thesis (M.S.)--University of Missouri-Columbia, 2005.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (January 22, 2007) Includes bibliographical references.

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7

Zhou, Yiqing, and 周一靑. "Advanced techniques for high speed wireless communications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B29296080.

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8

梁鉅輝 and Kui-fai Leung. "Enhancing transmission control protocol performance over wireless networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31227570.

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9

O'Brien, Kathleen. "Inductively coupled radio frequency power transmission system for wireless systems and devices /." Aachen : Shaker, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015959229&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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10

Yang, Daiqin. "Transmission scheduling in single-hop and multi-hop wireless networks." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37319371.

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11

Yang, Daiqin, and 楊代琴. "Transmission scheduling in single-hop and multi-hop wireless networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37319371.

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12

Huang, Yuanliang. "Study of advanced techniques in high speed wireless transmissions." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36824653.

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13

Huang, Yuanliang, and 黃源良. "Study of advanced techniques in high speed wireless transmissions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36824653.

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14

Handel, Peter. "Multimedia delivery in a wireless environment." [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE0000542.

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15

Yuan, Yin. "Transmission power control in wireless ad-hoc networks /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?ECED%202008%20YUAN.

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16

Kurpjuhn, Tobias P. [Verfasser]. "Transmission Strategies in Wireless MIMO Communication Systems / Tobias P Kurpjuhn." Aachen : Shaker, 2004. http://d-nb.info/1170537502/34.

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17

Lai, Lifeng. "Multiuser wireless networks the user cooperation perspective." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1186425130.

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18

Nguyen, Anh Van. "Concatenated space-time coding for wireless systems." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/13533.

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19

Sun, Qiong, and 孙琼. "Topology-transparent distributed scheduling in wireless networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44904101.

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20

Alastalo, Ari. "Microelectromechanical resonator-based components for wireless communications : filters and transmission lines /." Espoo VTT, 2006. http://www.vtt.fi/inf/pdf/publications/2006/P616.pdf.

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21

Hui, Chui Ying. "Broadcast algorithms and caching strategies for mobile transaction processing." HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/781.

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22

Li, Yang. "Models and applications of wireless networks in rural environments." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&amp.

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Анотація:

With the unprecedented growth of the communication industry that the world is experiencing, the demand from rural inhabitants for high quality communications at an economically affordable cost is growing. However, rural areas are rather restricted from deploying communication services due to the rough natural environment, and the shortage of rudimentary communication facilities and technical personnel. Appropriate models for building rural wireless networks and a concomitant simulation environment are, therefore, expected to enable the construction of technologically-optimal and economically-efficient networks in specified rural areas.

The research has set up two independent models, one for the economic need and the other for the technical need of building networks in rural areas. One model was the Impact of Telecommunications Model, which disclosed the importance of building a wireless network in specified rural areas by choosing an economic parameter to forecast the profitability of the network. The other was the Service Model, which collected primitive data from given rural areas and abstracted these data by flowing them through four technical layers to form the predicted technical wireless network. Both of the models had been applied to real-world cases to demonstrate how to use them.

A simulation environment was finally designed and implemented to realize the above two models for the sake of instantiation. This environment could simulate the specified rural network by constructing a wireless network on the invented areas and evaluating its quality and economic efficiency. It was written in Scilab simulation language, which was an open source.

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23

Yin, Bolian. "Adaptive clustering and transmission range adjustment for topology control in wireless sensor networks." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4485.

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Thesis (Ph. D.) University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 10, 2007) Vita. Includes bibliographical references.

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24

Wennerström, Hjalmar. "Meteorological impact and transmission errors in outdoor wireless sensor networks." Licentiate thesis, Uppsala universitet, Avdelningen för datorteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-227639.

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Wireless sensor networks have been deployed outdoors ever since their inception. They have been used in areas such as precision farming, tracking wildlife, and monitoring glaciers. These diverse application areas all have different requirements and constraints, shaping the way in which the sensor network communicates. Yet something they all share is the exposure to an outdoor environment, which at times can be harsh, uncontrolled and difficult to predict. Therefore, understanding the implications of an outdoor environment is an essential step towards reliable wireless sensor network operations. In this thesis we consider aspects of how the environment influence outdoor wireless sensor networks. Specifically, we experimentally study how meteorological factors impact radio links, and find that temperature is most significant. This motivates us to further study and propose a first order model describing the impact of temperature on wireless sensor nodes. We also analyze transmission errors in an outdoor wireless sensor networks, identifying and explaining patterns in the way data gets corrupted. The findings lead to a design and evaluation of an approach for probabilistic recover of corrupt data in outdoor wireless sensor networks. Apart from the experimental findings we have conducted two different outdoor deployments for which large data sets has been collected, containing both link and meteorological measurements.
WISENET

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25

Schulz-Rittich, Peter. "Opportunistic transmission strategies for wireless multiuser systems with imperfect channel knowledge /." Aachen : Shaker, 2006. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016034346&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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26

Sinn, Vincent [Verfasser]. "Efficient Block Transmission Systems for High Speed Wireless Communications / Vincent Sinn." Aachen : Shaker, 2005. http://d-nb.info/1186588268/34.

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27

O'Brien, Kathleen [Verfasser]. "Inductively Coupled Radio Frequency Power Transmission System for Wireless Systems and Devices / Kathleen O'Brien." Aachen : Shaker, 2007. http://d-nb.info/1166516717/34.

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28

Kang, Ajay I. S. "Algorithms for reduced content document synchronization." [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE0000549.

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29

Huang, Fei, and 黄菲. "Design and analysis of transmission protocols in wireless networks with smart antennas." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46421610.

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30

Zhong, Xin. "Speech coding and transmission for improved automatic recognition in communication networks." Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04072004-180252/unrestricted/zhong%5Fxin%5F200312%5Fphd.pdf.

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31

Motahari, Bidgoli Seyed Mohammad Amin. "An Optical Design Configuration for Wireless Data Transmission." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2439.

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The concept of 2D barcodes is of great relevance for use in wireless data transmission between handheld electronic devices. In a typical setup, any file on a cell phone for example can be transferred to a second cell phone through a series of images on the LCD which are then captured and decoded through the camera of the second cell phone. In this research, a new approach for data modulation in 2D barcodes is introduced, and its performance is evaluated in comparison to other standard methods of barcode modulation. In the proposed method, Orthogonal Frequency Division Multiplexing (OFDM) modulation is used together with Differential Phase Shift Keying (DPSK) over adjacent frequency domain elements to modulate intensity of individual pixels. It is shown that the bit error rate performance of the proposed system is superior to the current state of the art in various scenarios. A specific aim of this study is to establish a system that is proven tolerant to camera motion, picture blur and light leakage within neighboring pixels of an LCD. Furthermore, intensity modulation requires the input signal used to modulate a light source to be positive, which requires the addition of a dc bias. In the meantime, the high crest factor of OFDM requires a lower modulation index to limit clipping distortion. These two factors result in poor power efficiency in radio over fiber applications in which signal bandwidth is generally much less than the carrier frequency. In this study, it is shown that clipping a bipolar radio frequency signal at zero level, when it has a carrier frequency sufficiently higher than its bandwidth, results in negligible distortion in the pass band and most of the distortion power is concentrated in the baseband. Consequently, with less power provided to the optical carrier, higher power efficiencies and better receiver sensitivity will result. Finally, a more efficient optical integrated system is introduced to implement the proposed intensity modulation method which is optimized for radio over fiber applications.

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32

Wang, Li, and 王立. "Channel adaptive fair queueing in wireless packet data networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31226802.

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33

Cheng, Zhenlan. "Link level performance of wireless multicarrier transmission systems under real-world constraints /." [S.l.] : [s.n.], 2005. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=15954.

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34

Hueske, Klaus [Verfasser]. "Low Complexity Equalization Concepts for Spectral Efficient Wireless Transmission Systems / Klaus Hueske." München : Verlag Dr. Hut, 2012. http://d-nb.info/102171948X/34.

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35

Wang, Shendi. "Efficient transmission design for machine type communications in future wireless communication systems." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/23647.

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With a wide range of potential applications, the machine type communication (MTC) is gaining a tremendous interest among mobile network operators, system designers, MTC specialist companies, and research institutes. The idea of having electronic devices and systems automatically connected to each other without human intervention is one of the most significant objectives for future wireless communications. Low data rate transmission and the requirement for low energy consumption are two typical characteristics for MTC applications. In terms of supporting low cots MTC devices, industrial standards will be more efficient if designers can re-use many features of existing radio access technologies. This will yield a cost effective solution to support MTC in future communication systems. This thesis investigates efficient MTC waveform and receiver designs for superior signal transmission quality with low operational costs. In terms of the downlink receiver design, this thesis proposes a novel virtual carrier (VC) receiver system for MTC receivers, which aims to reduce the maximum bandwidth to improve the data processing efficiency and cost-efficiency by using analogue filters to extract only sub-carriers of interest. For the VC receiver systems, we thus reduce the sampling rate in order to reduce the number of subsequent processing operations, which significantly reduces the analogue-to-digital converter (ADC) cost and power consumption while providing high signal to interference noise ratio (SINR) and low bit to error rate (BER) to support low data rate MTC devices. Our theoretical equations account for the interference effect of aliasing on the sub-carrier location, and this helps the system designer to evaluate what kind of filters and receiver sampling rate can be used to balance the energy cost and detection performance. In terms of the uplink waveform design, considering the enhanced number of MTC devices in the future communication systems, i.e. the fifth generation (5G) communications, the same tight synchronisation as used in today appears not to be cost-effective or even possible. Synchronisation signals, which aim to provide a perfect time or frequency synchronisation in the current fourth generation (4G) communication systems (known as the long-term evolution, LTE), is much more costly for low data rate MTC transmissions. The system bandwidth will be significantly reduced if a base station tries to synchronise all received signals among hundreds or thousands MTC devices in one transmission time period. In terms of relaxing the synchronisation requirements, this thesis compares and analyses the side-lobe reduction performance for several candidate multi-carrier waveforms to avoid these problems. We also propose the infinite impulse response universal filtered multi-carrier (UFMC) system and the overlap and add UFMC system, which significantly reduce the processing complexity compared with the state of the art UFMC techniques. This thesis derives closed-form expressions for the interference caused by time offsets between adjacent unsynchronised MTC users. Our analytical equations can be used in both simple and complex time-offset transmission scenarios, and enable the system designer to evaluate the SINR, the theoretical Shannon capacity and the BER performance.

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36

Silva, Hugo Filipe Orfão da. "MIMO techniques implementation on FPGA for future wireless transmission systems (4G/LTE)." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14540.

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Анотація:

Mestrado em Engenharia Eletrónica e Telecomunicações
This work alludes to 4G LTE technology. Techniques used for the same technology are described namely precoding and Alamouti coding and decoding. An Alamouti’s 4G system implemented to FPGA using the Xilinx System is introduced. The work also addresses the PAPR problem due to the reference pilots in the platform being generated all in phase. In this work a random pilot generator was implemented which combats the high peak power. In the receiver it was taken into account the new generation method to perform channel estimation correctly. A technique is discussed to increase the energy efficiency of the system based on PAPR reduction.
O presente trabalho faz alusão à tecnologia 4G LTE. São descritas técnicas usadas na mesma tecnologia nomeadamente de precoding e codificação e descodificação Alamouti. É introduzido um sistema Alamouti 4G implementado para FPGAs usando o programa System Generator da Xilinx. O trabalho também aborda o problema do PAPR devido aos pilotos de referência na plataforma estarem sendo gerados todos em fase. Neste trabalho, um gerador aleatório de pilotos foi implementado que combate a potência de pico (PAPR). No receptor levou-se em conta o método desta nova geração para realizar a estimativa de canal corretamente.

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37

Zhou, Xiangyun. "Transmission resource allocation in multi-antenna wireless communication systems with channel uncertainty." Phd thesis, Institute of Electrical and Electronics Engineers (IEEE), 2013. http://hdl.handle.net/1885/9828.

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In this thesis we investigate the design of transmission resource allocation in current and future wireless communication systems. We focus on systems with multiple antennas and characterize their performance from an information-theoretic viewpoint. The goal of this work is to provide practical transmission and resource allocation strategies taking into account imperfections in estimating the wireless channel, as well as the broadcast nature of the wireless channel. In the first part of the thesis, we consider training-based transmission schemes in which pilot symbols are inserted into data blocks to facilitate channel estimation. We consider one-way training-based systems with and without feedback, as well as two-way training-based systems. Two-way training enables both the transmitter and the receiver to obtain the channel state information (CSI) through reverse training and forward training, respectively. In all considered cases, we derive efficient strategies for transmit time and/or energy allocation among the pilot and data symbols. These strategies usually have analytical closed-form expressions and can achieve near optimal capacity performance evidenced by extensive numerical analysis. In one-way training-based systems without feedback, we consider both spatially independent and correlated channels. For spatially independent channels, we provide analytical bounds on the optimal training length and study the optimal antenna conÂ¯guration that maximizes an ergodic capacity lower bound. For spatially correlated channels, we provide simple pilot and data transmission strategies that are robust under least-favorable channel correlation conditions. In one-way training-based systems with feedback, we study channel gain feedback (CGF), channel covariance feedback (CCF) and hybrid feedback. For spatially independent channels with CGF, we show that the solutions to the optimal training length and energy coincide with those for systems without feedback. For spatially correlated channels with CCF, we propose a simple transmission scheme, taking into account the fact that the optimal training length is at most as large as the number of transmit antennas. We then provided solution to the optimal energy allocation between pilot and data transmissions, which does not depend on the channel spatial correlation under a mild condition. Our derived resource allocation strategies in CGF and CCF systems are extended to hybrid CCF-CGF systems. In two-way training-based systems, we provide analytical solutions to the transmit power distribution among the different training phases and the data transmission phase. These solutions are shown to have near optimal symbol error rate (SER) and capacity performance. We find that the use of two-way training can provide noticeable performance improvement over reverse training only when the system is operating at moderate to high signal-to-noise ratio (SNR) and using high-order modulations. While this improvement from two-way training is insignificant at low SNR or low-order modulations. In the second part of the thesis, we consider transmission resource allocation in security-constrained systems. Due to the broadcast nature of the wireless medium, security is a fundamental issue in wireless communications. To guarantee secure communication in the presence of eavesdroppers, we consider a multi-antenna transmission strategy which sends both an information signal to the intended receiver and a noise-like signal isotropically to confuse the eavesdroppers. We study the optimal transmit power allocation between the information signal and the artificial noise. In particular, we show that equal power allocation is a near optimal strategy for non-colluding eavesdroppers, while more power should be used to generate the artificial noise for colluding eavesdroppers. In the presence of channel estimation errors, we find that it is better to create more artificial noise than to increase the information signal strength.

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38

Soundararajan, Srivathsan Agrawal Prathima. "Scheduling in WiMAX based wireless networks." Auburn, Ala, 2008. http://hdl.handle.net/10415/1449.

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39

王徐芳 and Xufang Wang. "Multiresolution joint source and channel coding for wireless communications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31225299.

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40

Yamashita, Shota. "Coexistence of Wireless Communication and Non-communication Systems." Kyoto University, 2018. http://hdl.handle.net/2433/232420.

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41

Ng, Ka Wai. "Generalized bit and power allocation for single and multi-user OFDM MIMO system in frequency selective fading channel /." View abstract or full-text, 2003. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202003%20NG.

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42

Khan, Nabeel Pervaiz. "Energy efficient communication and rate control algorithms for wireless sensor networks." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 114 p, 2009. http://proquest.umi.com/pqdweb?did=1818417511&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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43

Yang, Guanghua. "Adaptive unequal error protection for wireless video transmissions." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37153791Bib.

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44

Yang, Guanghua, and 楊光華. "Adaptive unequal error protection for wireless video transmissions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37153791.

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45

Lai, Chengdi, and 赖成迪. "Congestion control for transmission control protocol (TCP) in wirelessnetworks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47102445.

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The best MPhil thesis in the Faculties of Dentistry, Engineering, Medicine and Science (University of Hong Kong), Li Ka Shing Prize,2010-11.
published_or_final_version
Electrical and Electronic Engineering
Master
Master of Philosophy

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46

Montes, Luis Roger Atero. "Resilient evolutionary source coding for wireless mobile TV/video image communication systems." Thesis, Staffordshire University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311039.

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47

Wang, Yanpeng. "Design and Analysis of GFDM-Based Wireless Communication Systems." Doctoral thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/69666.

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Le multiplexage généralisé par répartition en fréquence (GFDM), une méthode de traitement par blocs de modulation multiporteuses non orthogonales, est une candidate prometteuse pour les technologies de forme d'onde pour les systèmes sans fil au-delà de la cinquième génération (5G). La capacité du GFDM à ajuster de manière flexible la taille du bloc et le type de filtres de mise en forme des impulsions en fait une méthode appropriée pour répondre à plusieurs exigences importantes, comme une faible latence, un faible rayonnement hors bande (OOB) et des débits de données élevés. En appliquant aux systèmes GFDM la technique des systèmes à entrées multiples et sorties multiples (MIMO), la technique de MIMO massif ou des codes de contrôle de parité à faible densité (LDPC), il est possible d'améliorer leurs performances. Par conséquent, l'étude de ces systèmes combinés sont d'une grande importance théorique et pratique. Dans cette thèse, nous étudions les systèmes de communication sans fil basés sur le GFDM en considérant trois aspects. Tout d'abord, nous dérivons une borne d'union sur le taux d'erreur sur les bits (BER) pour les systèmes MIMO-GFDM, technique qui est basée sur des probabilités d'erreur par paires exactes (PEP). La PEP exacte est calculée en utilisant la fonction génératrice de moments(MGF) pour les détecteurs à maximum de vraisemblance (ML). La corrélation spatiale entre les antennes et les erreurs d'estimation de canal sont prises en compte dans l'environnement de canal étudié. Deuxièmement, les estimateurs et les précodeurs de canal de faible complexité basés sur une expansion polynomiale sont proposés pour les systèmes MIMO-GFDM massifs. Des pilotes sans interférence sont utilisés pour l'estimation du canal basée sur l'erreur quadratique moyenne minimale(MMSE) pour lutter contre l'influence de la non-orthogonalité entre les sous-porteuses dans le GFDM. La complexité de calcul cubique peut être réduite à une complexité d'ordre au carré en utilisant la technique d'expansion polynomiale pour approximer les inverses de matrices dans l'estimation MMSE conventionnelle et le précodage. De plus, nous calculons les limites de performance en termes d'erreur quadratique moyenne (MSE) pour les estimateurs proposés, ce qui peut être un outil utile pour prédire la performance des estimateurs dans la région de Es/N0 élevé. Une borne inférieure de Cramér-Rao(CRLB) est dérivée pour notre modèle de système et agit comme une référence pour les estimateurs. La complexité de calcul des estimateurs de canal proposés et des précodeurs et les impacts du degré du polynôme sont également étudiés. Enfin, nous analysons les performances de la probabilité d'erreur des systèmes GFDM combinés aux codes LDPC. Nous dérivons d'abord les expressions du ratio devraisemblance logarithmique (LLR) initiale qui sont utilisées dans le décodeur de l'algorithme de somme de produits (SPA). Ensuite, basé sur le seuil de décodage, nous estimons le taux d'erreur de trame (FER) dans la région de bas Eb/N0 en utilisant le BER observé pour modéliser les variations du canal. De plus, une borne inférieure du FER du système est également proposée basée sur des ensembles absorbants. Cette borne inférieure peut agir comme une estimation du FER dans la région de Eb/N0 élevé si l'ensemble absorbant utilisé est dominant et que sa multiplicité est connue. La quantification a également un impact important sur les performances du FER et du BER. Des codes LDPC basés sur un tableau et construit aléatoirement sont utilisés pour supporter les analyses de performances. Pour ces trois aspects, des simulations et des calculs informatiques sont effectués pour obtenir des résultats numériques connexes, qui vérifient les méthodes proposées.
Generalized frequency division multiplexing (GFDM) is a block-processing based non-orthogonal multi-carrier modulation scheme, which is a promising candidate waveform technology for beyondfifth-generation (5G) wireless systems. The ability of GFDM to flexibly adjust the block size and the type of pulse-shaping filters makes it a suitable scheme to meet several important requirements, suchas low latency, low out-of-band (OOB) radiation and high data rates. Applying the multiple-inputmultiple-output (MIMO) technique, the massive MIMO technique, or low-density parity-check (LDPC)codes to GFDM systems can further improve the systems performance. Therefore, the investigation of such combined systems is of great theoretical and practical importance.This thesis investigates GFDM-based wireless communication systems from the following three aspects. First, we derive a union bound on the bit error rate (BER) for MIMO-GFDM systems, which is based on exact pairwise error probabilities (PEPs). The exact PEP is calculated using the moment-generating function (MGF) for maximum likelihood (ML) detectors. Both the spatial correlation between antennas and the channel estimation errors are considered in the investigated channel environment. Second, polynomial expansion-based low-complexity channel estimators and precoders are proposed for massiveMIMO-GFDM systems. Interference-free pilots are used in the minimum mean square error (MMSE) channel estimation to combat the influence of non-orthogonality between subcarriers in GFDM. The cubic computational complexity can be reduced to square order by using the polynomial expansion technique to approximate the matrix inverses in the conventional MMSE estimation and precoding. In addition, we derive performance limits in terms of the mean square error (MSE) for the propose destimators, which can be a useful tool to predict estimators performance in the high Es/N0 region. ACramér-Rao lower bound (CRLB) is derived for our system model and acts as a benchmark for the estimators. The computational complexity of the proposed channel estimators and precoders, and the impacts of the polynomial degree are also investigated. Finally, we analyze the error probability performance of LDPC coded GFDM systems. We first derive the initial log-likelihood ratio (LLR) expressions that are used in the sum-product algorithm (SPA) decoder. Then, based on the decoding threshold, we estimate the frame error rate (FER) in the low Eb/N0 region by using the observed BER to model the channel variations. In addition, a lower bound on the FER of the system is also proposed based on absorbing sets. This lower bound can act as an estimate of the FER in the highEb/N0 region if the absorbing set used is dominant and its multiplicity is known. The quantization scheme also has an important impact on the FER and BER performances. Randomly constructed and array-based LDPC codes are used to support the performance analyses. For all these three aspects,software-based simulations and calculations are carried out to obtain related numerical results, whichverify our proposed methods.

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48

Wetz, Matthias [Verfasser]. "Transmission methods for wireless multi carrier systems in time-varying environments / Matthias Wetz." Ulm : Universität Ulm. Fakultät für Ingenieurwissenschaften und Informatik, 2011. http://d-nb.info/1018024808/34.

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49

Koike, Toshiaki. "Space-time-frequency signal processing for spectrum-efficient multiple-antenna wireless transmission systems." 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/144509.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(情報学)
甲第11908号
情博第180号
新制||情||40(附属図書館)
23688
UT51-2005-N742
京都大学大学院情報学研究科通信情報システム専攻
(主査)教授吉田進, 教授酒井英昭, 教授佐藤亨
学位規則第4条第1項該当

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50

Spencer, Quentin H. "Transmission Strategies for Wireless Multi-user, Multiple-Input, Multiple-Output Communication Channels." Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd378.pdf.

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