Joint turbo equalization and turbo TCM for mobile communication systems

This paper deals with a new receiver scheme that combines turbo equalization and turbo trellis coded modulation (turbo TCM). This receiver serially concatenates a soft input soft output (SISO) equalizer and a soft-out symbol-by-symbol MAP turbo TCM decoder through an iterative process. In certain cases, the joint turbo equalization and turbo TCM scheme can totally overcome the channel frequency selectivity and obtain high bandwidth efficiency and greater coding gain. This scheme has modest complexity since a sub-optimal reduced-state MAP equalization algorithm and simple turbo TCM component codes are employed. Simulation results show that this receiver can achieve comparable performance with the turbo TCM receiver on a non-selective Gaussian channel with coding.