A two-symbols/branch MBCM scheme based on 8-PSK constellation under fading channels

A two-symbols/branch scheme of multiple block coded modulation (MBCM) is investigated under fading channels. Compared with a conventional scheme of block coded modulation (BCM), this two-symbols/branch MBCM scheme greatly increases the minimum squared Euclidean distance (MSED), minimum symbol distance (MSD), and minimum product distance (MPD). These three distances determine the bit-error-rate (BER) performance under either Gaussian or fading channels. A pilot symbol assisted fading compensation, as well as the techniques of symbol interleaving and branch weighting, are employed to combat the effect of channel fading. Through computer simulations, it is shown that large coding gains are obtained under both Rayleigh and Rician fading channels.