Author Description

This dissertation, "Error-rate Evaluation and Optimization for Space-time Codes" by Zhi, Zhang,, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled Error-Rate Evaluation and Optimization for Space-Time Codes Submitted by Zhang Zhi for the degree of Doctor of Philosophy at The University of Hong Kong in August 2007 Error-rate evaluation and optimization are important issues for the study of Space-Time (S-T) codes. This thesis investigates the accuracy and efficiency of error-rate evaluation for S-T codes. The accuracy of the optimization and the convenience of using the optimized results over a range of signal-to-noise ratios (SNRs) are also investigated. An exact close-form Pair-wise Error Probability (PEP) is derived which is based on a proposed simple solution to determine the coefficients of the partial fraction expansion, thus eliminating the complexity to obtain any high order derivatives. The Union bound using the proposed exact PEP can produce accurate BER performance in moderate and high SNR regions. However the calculation needs to be repeated for every SNR value investigated because of the complicated mathematical structures involved in the proposed close-form PEP. To efficiently evaluate the error rate, an alternative power series representation for the exact PEP is proposed to reduce the computational load, which can produce accurate results within a certain region of convergence. When the exact Union bound (EUB) is used for S-T codes optimization, the results usually vary with SNR, which is inconvenient in practical use. Thus a Common funct