A new result on turbo coded QO-STBC schemes

In this letter, we present a new result on turbo coded quasi orthogonal space time block coding (QO-STBC) schemes. Proper utilization of soft decision information is one of the important factors affecting the performance of turbo codes. If a space time block coding (STBC) scheme is used with turbo codes, the output of the STBC decoder must be fed into a turbo code decoder as soft decision information. Therefore, the performance of turbo codes depends on how the STBC scheme generates soft decision information from its detection process. In this letter, we investigate the performance of turbo coded QO-STBC schemes, and present the optimum soft decision metrics.