Channel coding and space-time coding for wireless channels

Abstract

This thesis is based on the research of channel coding. First, we give an introduction to the family of conventional Bose-Chauduri-Hocquenghem (BCH) codes, characterising the performance of various BCH codes. Then we further our research into turbo codes employing BCH codes as the component codes. Various decoding algorithms are presented for turbo codes. This is followed by our simulation results, studying the effects of various parameters, affecting the performance of turbo codes.Subsequently, another form of non-binary block codes, referred to as Redundant Residue Number System (RRNS) codes, which exhibit identical distance properties to the well-established Reed-Solomon (RS) codes, are investigated. Different bit-to-symbol mapping schemes are proposed, which result in systematic and non-systematic RRNS codes. An RRNS decoder is proposed, which accepts soft inputs and provide soft outputs. This facilitates the iterative decoding of turbo RRNS codes.Our investigations into channel coding are also expanded to study space-time codes, which are constituted by jointly designed channel coding, modulation, transmit diversity and optional receiver diversity schemes. Specifically, combined space-time block codes and different channel codecs studied. Various simulation results are presented for space-time block codes using no channel coding. This is followed by the investigations of the bit-to-symbol mapping of the binary channel coded bits to higher modulation constellations. Finally, the performance of various channel codecs is compared by considering their estimated complexity in conjunction with space-time block coding.In the last chapter, space-time trellis codes are then compared to the class of space-time block codes in conjunction with a range of channel codes over wideband channels. Various factors affecting the performance of space-time block codes are investigated. Finally, space-time coded adaptive Orthogonal Frequency Division Multiplexing (AOFDM) is investigated.</p