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Distributed Space-Time Block Codes in Wireless Cooperative NetworksYI, ZHIHANG 02 July 2009 (has links)
In cooperative networks, relays cooperate and form a distributed multi-antenna system to provide spatial diversity. In order to achieve high bandwidth efficiency, distributed space-time block codes (DSTBCs) are proposed and have been studied extensively.
Among all DSTBCs, this thesis focuses on the codes which are single-symbol maximum likelihood (ML) decodable and can achieve the full diversity order.
This thesis presents four works on single-symbol ML decodable DSTBCs. The first work proposes the row-monomial distributed orthogonal space-time block codes (DOSTBCs). We find an upper bound of the data-rate of the row-monomial DOSTBC and construct the codes achieving this upper bound. In the second work, we first study the general DOSTBCs and derive an upper bound of the data-rate of the DOSTBC. Secondly, we propose the row-monomial DOSTBCs with channel phase information (DOSTBCs-CPI) and derive an upper bound of the data-rate of those codes. Furthermore, we find the actual row-monomial DOSTBCs-CPI which achieve the upper bound of the data-rate.
In the third and fourth works of this thesis, we focus on error performance analysis of single-symbol ML decodable DSTBCs. Specifically, we study the distributed Alamouti's code in dissimilar cooperative networks. In the third work, we assume that the relays are blind relays and we derive two very accurate approximate bit error rate (BER) expressions of the distributed Alamouti's code. In the fourth work, we assume that the relays are CSI-assisted relays. When those CSI-assisted relays adopt the amplifying coefficients that was proposed in [33] and widely used in many previous publications, upper and lower bounds of the BER of the distributed Alamouti's code are derived. Very surprisingly, the lower bound indicates that the code cannot achieve the full diversity order when the CSI-assisted relays adopt the amplifying coefficients proposed in [33]. Therefore, we propose a new threshold-based amplifying coefficient and it makes the code achieve the full diversity order two. Moreover, three optimum and one suboptimum schemes are developed to calculate the threshold used in this new amplifying coefficient. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2009-06-27 19:07:47.066
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Performance of high rate space-time trellis coded modulation in fading channels.Ayodeji, Sokoya Oludare. January 2005 (has links)
Future wireless communication systems promise to offer a variety of multimedia services which require reliable transmission at high data rates over wireless links. Multiple input multiple output (MIMO) systems have received a great deal of attention because they provide very high data rates for such links. Theoretical studies have shown that the quality provided by MIMO systems can be increased by using space-time codes. Space-time codes combine both space (antenna) and time diversity in the transmitter to increase the efficiency of MIMO system. The three primary approaches, layered spacetime architecture, space-time trellis coding (STTC) and space-time block coding (STBC) represent a way to investigate transmitter-based signal processing for diversity exploitation and interference suppression. The advantages of STBC (i.e. low decoding complexity) and STTC (i.e. TCM encoder structure) can be used to design a high rate space-time trellis coded modulation (HR-STTCM). Most space-time codes designs are based on the assumption of perfect channel state information at the receiver so as to make coherent decoding possible. However, accurate channel estimation requires a long training sequence that lowers spectral efficiency. Part of this dissertation focuses on the performance of HR-STTCM under non-coherent detection where there is imperfect channel state information and also in environment where the channel experiences rapid fading. Prior work on space-time codes with particular reference to STBC systems in multiuser environment has not adequately addressed the performance of the decoupled user signalto-noise ratio. Part of this thesis enumerates from a signal-to-noise ratio point of view the performance of the STBC systems in multiuser environment and also the performance of the HR-STTCM in such environment. The bit/frame error performance of space-time codes in fading channels can be evaluated using different approaches. The Chemoff upper-bound combined with the pair state generalized transfer function bound approach or the modified state transition diagram transfer function bound approach has been widely used in literature. However, although readily detennined, this bound can be too loose over nonnal signal-to-noise ranges of interest. Other approaches, based on the exact calculation of the pairwise error probabilities, are often too cumbersome. A simple exact numerical technique, for calculating, within any desired degree of accuracy, of the pairwise error probability of the HR-STTCM scheme over Rayleigh fading channel is proposed in this dissertation. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2005.
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Noncoherent communications using space-time trellis codesGu, Yu January 2008 (has links)
In the last decade much interest has been shown in space-time trellis codes (STTCs) since they can offer coding gain along with the ability to exploit the space and time diversity of MIMO channels. STTCs can be flexibly designed by trading off performance versus complexity. The work of Dayal [1] stated that if training symbols are used together with data symbols, then a space-time code can be viewed as a noncoherent code. The authors of [1] described the migration from coherent space-time codes to training assisted noncoherent space-time codes. This work focuses on the development of training assisted noncoherent STTCs, thus extending the concept of noncoherent training codes to STTCs. We investigate the intrinsic link between coherent and noncoherent demod- ulation. By analyzing noncoherent STTCs for up to four transmit antennas, we see that they have similar performance deterioration to noncoherently demodulated M-PSK using a single antenna. Various simulations have been done to confirm the analysis.
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Wireless systems incorporating full-diversity single-symbol decodable space-time block codes performance evaluations and developments /Lee, Hoo-jin. January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
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Noncoherent communications using space-time trellis codes : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Engineering in Electrical and Electronic Engineering from the University of Canterbury, Christchurch, New Zealand /Gu, Yu. January 1900 (has links)
Thesis (M.E.)--University of Canterbury, 2008. / Typescript (photocopy). "June 2008." Includes bibliographical references (p. 87-96). Also available via the World Wide Web.
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Space-time coding and space-time channel modelling for wireless communications /Lamahewa, Tharaka Anuradha. January 2006 (has links)
Thesis (Ph.D) -- Australian National University, 2006.
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Adaptive equalization and capacity analysis for amplify-and-forward relays : a thesis submitted in fulfillment of the requirements for the degree of Doctor of Philosophy in Electrical and Electronic Engineering, University of Canterbury, Christchurch, New Zealand /Firag, Abdulla. January 1900 (has links)
Thesis (Ph. D.)--University of Canterbury, 2008. / Typescript (photocopy). "December 2008." Includes bibliographical references (p. 165-174). Also available via the World Wide Web.
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Cooperative wireless communications protocol design and performance analysis /Vardhe, Kanchan G. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains xii, 107 p. : ill. (some col.). Includes abstract. Includes bibliographical references.
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A family of space-time block codes for wireless communications a thesis /Yang, Ning, January 1900 (has links)
Thesis (Ph. D.)--Northeastern University, 2008. / Title from title page (viewed May 27, 2009). Graduate School of Engineering, Dept. of Electrical and Computer Engineering. Includes bibliographical references (p. 101-106).
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Feedback methods for multiple-input multiple-output wireless systemsLove, David James, January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Vita. Includes bibliographical references.
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