Modified MAP algorithm for extended turbo BCH codes and turbo equalisers

Author

Liew, T.H. ; Yeap, B.L. ; Woodard, J. ; Hanzo, L.

Author_Institution

Dept. of Electron. & Comput. Sci., Southampton Univ., UK

fYear

2000

fDate

2000

Firstpage

185

Lastpage

189

Abstract

The maximum a-posteriori (MAP) algorithm is modified in order to incorporate the parity check bit of extended BCH codes into calculating the log likelihood ratio (LLR) of the coded bits. The algorithm is then used jointly with channel equalisation-in a scheme referred to as turbo equalisation-in order to mitigate the effects of intersymbol interference (ISI) introduced by dispersive channels. The performance of the extended BCH codes is evaluated and compared to that of conventional BCH codes. For example, the extended BCH(32,26) code was found to outperform the conventional BCH(31,26) code by approximately 0.5-1.0 dB at a bit error rate (BER) of 10^-5 over dispersive Rayleigh-fading channels

Keywords

BCH codes; BER; ISI; bit error rate; channel equalisation; decoding; dispersive Rayleigh fading channels; extended turbo BCH codes; intersymbol interference; log likelihood ratio; maximum a-posteriori algorithm; modified MAP algorithm; parity check bit; performance evaluation; turbo equalisation; turbo equalisers;

fLanguage

English

Publisher

iet

Conference_Titel

3G Mobile Communication Technologies, 2000. First International Conference on (Conf. Publ. No. 471)

Conference_Location

London

Print_ISBN

0-85296-726-8

Type

conf

DOI

10.1049/cp:20000039

Filename

858235