On Coding for Orthogonal Frequency Division Multiplexing Systems

Type of content
Theses / Dissertations
Publisher's DOI/URI
Thesis discipline
Electrical Engineering
Degree name
Doctor of Philosophy
Publisher
University of Canterbury. Electrical and Computer Engineering
Journal Title
Journal ISSN
Volume Title
Language
Date
2006
Authors
Clark, Alan
Abstract

The main contribution of this thesis is the statistical analysis of orthogonal frequency di- vision multiplexing (OFDM) systems operating over wireless channels that are both fre- quency selective and Rayleigh fading. We first describe the instantaneous capacity of such systems using a central limit theorem, as well as the asymptotic capacity of a power lim- ited OFDM system as the number of subcarriers approaches infinity. We then analyse the performance of uncoded OFDM systems by first developing bounds on the block error rate. Next we show that the distribution of the number of symbol errors within each block may be tightly approximated, and derive the distribution of an upper bound on the total variation distance. Finally, the central result of this thesis proposes the use of lattices for encodingOFDMsystems. For this, we detail a particular method of using lattices to encode OFDMsystems, and derive the optimalmaximumlikelihood decodingmetric. Generalised Minimum Distance (GMD) decoding is then introduced as a lower complexity method of decoding lattice encoded OFDM. We derive the optimal reliability metric for GMD decod- ing of OFDM systems operating over frequency selective channels, and develop analytical upper bounds on the error rate of lattice encoded OFDM systems employing GMD decod- ing.

Description
Citation
Keywords
Wireless Communication, Orthogonal Frequency Division Multiplexing, Error Control Coding.
Ngā upoko tukutuku/Māori subject headings
ANZSRC fields of research
Rights
Copyright Alan Clark