A low complexity decoding algorithm for orthogonal space time block codes in frequency selective fading channels

Focusing on the problem that the orthogonality of Orthogonal Space-Time Block Codes (OSTBC) in frequency-selective fading channels is destroyed, a novel decoding scheme based on interference cancellation is proposed. This scheme adopts interference cancellation and interference nulling to cancel multipath interference, which is used in D-BLAST system. Thus the expected signals are detected effectively. Theoretical analysis and simulation result show that, compared with iterative interference cancellation decoding algorithm, this scheme can improve the bit error rate efficiently and reduce the decoding complexity at the same time. The proposed sheme is especially suitable for environments with small rank of channels.