Multiple antennas with a reduced iterative turbo decode for a DS/CDMA system

A combined diversity scheme of multiple turbo codes and multiple antennas for a synchronous direct sequence-code division multiple access (DS-CDMA) system over Rayleigh fading mobile radio channels is considered to improve the BER performance. In spite of the multiple structures, by employing a parallel mode decoding scheme the time delay becomes equivalent to that of a single turbo code system. Furthermore, the truncated trellis structure applied to MAP reduces the number of iterations from K for the original BCJR MAP to (K+1)/2 for the proposed MAP.