Decoupled maximum likelihood channel estimator for space-time block coded system

Abstract

A computationally efficient channel estimation scheme based on the decoupled maximum likelihood (DEML) algorithm is introduced for space-time block coded (STBC) system. The BER performance of the STBC system with the DEML channel estimator is obtained under spatially uncorrelated and correlated flat Rayleigh fading channels. It is shown that the DEML channel estimator could perform well only under uncorrelated fading channels. When the fading channels are correlated, a decorrelation algorithm is applied on the correlated signals before the DEML channel estimator is used. A general procedure on the generation of correlated Rayleigh fading envelops is also introduced in such case. In addition, an iterative ML detector is introduced to improve the system performance with the DEML channel estimator, both under uncorrelated and correlated fading channels.