Stochastic gradient algorithms for design of minimum error-rate linear dispersion codes in MIMO wireless systems

TitleStochastic gradient algorithms for design of minimum error-rate linear dispersion codes in MIMO wireless systems
Publication TypeJournal Article
Year of Publication2006
AuthorsWang, X. D., V. Krishnamurthy, and J. B. Wang
JournalIEEE Transactions on Signal Processing
Volume54
Pagination1242–1255
ISSN1053-587X
Abstract

Linear dispersion (LD) codes are a good candidate for high-data-rate multiple-input multple-ouput (MIMO) signaling. Traditionally LD codes were designed by maximizing the average mutual information, which cannot guarantee good error performance. This paper presents a new design scheme for LD codes that directly minimizes the block error rate (BLER) in MIMO channels with arbitrary fading statistics and various detection algorithms. For MIMO systems employing LD codes, the error rate does not admit an explicit form. Therefore, we cannot use deterministic optimization methods to design the minimum-error-rate LD codes. In this paper, we propose a simulation-based optimization methodology for the design of LD codes through stochastic approximation and simulation-based gradient estimation. The gradient estimation is done using the score function method originally developed in the discrete-event-system community. The proposed method can be applied to design the minimum-error-rate LD codes for a variety of detector structures including the maximum-likelihood (ML) detector and several suboptimal detectors. It can also design optimal codes under arbitrary fading channel statistics; in particular, it can take into account the knowledge of spatial fading correlation at the transmitter and receiver ends. Simulation results show that codes generated by the proposed new design paradigm generally outperform the codes designed based on algebraic number theory.

URLhttp://dx.doi.org/10.1109/TSP.2005.863122
DOI10.1109/TSP.2005.863122

a place of mind, The University of British Columbia

Electrical and Computer Engineering
2332 Main Mall
Vancouver, BC Canada V6T 1Z4
Tel +1.604.822.2872
Fax +1.604.822.5949
Email:

Emergency Procedures | Accessibility | Contact UBC | © Copyright 2020 The University of British Columbia