Decoding and equalization of unknown multipath channels based on block precoding and transmit-antenna diversity

Transmit-antenna diversity has been exploited previously to develop high-performance space-time coders and simple maximum-likelihood decoders for transmissions over known flat fading channels. Based on blocking and multiple transmit-antennas, this paper derives novel precoders and decoders that eliminate intersymbol interference and achieve transmit diversity gain in the unknown multipath channels. When unknown, channel status information is acquired blindly based on a deterministic variant of the constant-modulus algorithm. The system performance is evaluated both analytically and with simulations.