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.

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.

Thesis (M.E.)--University of Canterbury, 2008. / Typescript (photocopy). "June 2008." Includes bibliographical references (p. 87-96). Also available via the World Wide Web.

Thesis (Ph. D.)--University of Canterbury, 2008. / Typescript (photocopy). "December 2008." Includes bibliographical references (p. 165-174). Also available via the World Wide Web.

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.

Thesis (Ph. D.)--University of Texas at Austin, 2004. / Vita. Includes bibliographical references.

Multiple antennas help in combating the destructive effects of fading as well as improve the spectral efficiency of a communication system. Receive diversity techniques like maximal ratio receive combining have been popular means of introducing multiple antennas into communication systems. Space-time block codes present a way of introducing transmit diversity into the communication system with similar complexity and performance as maximal ratio receive combining. In this thesis we study the performance of space-time block codes in Rayleigh fading channel. In particular, the quasi-static assumption on the fading channel is removed to study how the space-time block coded system behaves in fast fading. In this context, the complexity versus performance trade-off for a space-time block coded receiver is studied. As a means to improve the performance of space-time block coded systems concatenation by convolutional codes is introduced. The improvement in the diversity order by the introduction of convolutional codes into the space-time block coded system is discussed. A general analytic expression for the error performance of a space-time block coded system is derived. This expression is utilized to obtain general expressions for the error performance of convolutionally concatenated space-time block coded systems utilizing both hard and soft decision decoding. Simulation results are presented and are compared with the analytical results. / Master of Science

Thesis (Ph.D.)--McMaster University, 2005. / Supervisor: Simon Haykin. Includes bibliographical references (leaves [126]-135).

Thesis (M.S.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed April 16, 2007) Includes bibliographical references (p. 38).

Thesis (M.Eng.)--Memorial University of Newfoundland, 2005. / Restricted until October 2006. Bibliography: leaves 118-121.