Space-time trellis coded 8PSK schemes for rapid Rayleigh fading channels

This paper presents the design of 8PSK space-time (ST) trellis codes suitable for rapid fading channels. The proposed codes utilize the design criteria of ST codes over rapid fading channels. Two different approaches have been used. The first approach maximizes the symbol-wise Hamming distance (HD) between signals leaving from or entering to the same encoder's state. In the second approach, set partitioning based on maximizing the sum of squared Euclidean distances (SSED) between the ST signals is performed; then, the branch-wise HD is maximized. The proposed codes were simulated over independent and correlated Rayleigh fading channels. Coding gains up to 4 dB have been observed over other ST trellis codes of the same complexity.