Space-Time Codes with Block-Orthogonal Structure and Their Simplified ML and Near-ML Decoding

Existing high-rate full diversity space-time codes (STC) always have high decoding complexity with traditional ML (maximum-likelihood) or near-ML decoding. Hence the decoding scheme with reduced complexity is required. In this paper, block-orthogonal structure is introduced for the first time, and most of the existing STC do have such structure. A simplified decoding is proposed to exploit the block-orthogonal structure of the code and reduce the complexity drastically without any extra loss in decoding performance.