A receiver algorithm for unitary space-time differentially encoded transmissions over FIR multipath channels

A radio-interface with space-time (ST) coding and processing promises to improve system capacity significantly over a variety of wireless channels. The paper proposes and analyzes a new receiver scheme with ST processing for unitary ST coded transmissions over finite impulse response (FIR) multipath fading channels. The proposed receiver employs a multiple element antenna and a fractionally-spaced sampling method. The symbol detection discussed is a deterministic subspace-based approach in a multiple-input multiple-output (MIMO) system framework, which exploits the antenna diversity, the structure of the unitary space-time code and the multiple-constant-modulus characteristics of the received signal. The paper gives a detailed description of the receiver algorithm and the simulation results for performance evaluation. Theoretically, this scheme is able to mitigate blindly the intersymbol-interference caused by multipath propagation. Monte-Carlo simulations demonstrate that the proposed receiver has a superior performance in FIR fading channels contaminated by additive-white-Gaussian-noise (AWGN).