Optimal detection for STBC MIMO systems in spatially correlated Rayleigh fast fading channels with imperfect channel estimation

An optimal detector for space-time block coded signals with pilot symbol assisted modulation in multiple-input multiple-output (MIMO) systems with imperfect channel estimation is proposed and investigated. We compare its performance with that of traditional mismatched detectors treating channel estimates as perfect in spatially and temporally correlated fading channels. The channel time variations are approximated by using the basis expansion model (BEM). Specifically, the discrete prolate spheroidal basis functions are used. In both spatially uncorrelated and spatially highly correlated MIMO Rayleigh fast fading channels, the optimal detector significantly outperforms the mismatched detectors including the one exploiting minimum mean square error channel estimates.