Adaptive Modulation using Differential STBC in Rayleigh Fading Channel

In this paper, we consider adaptive modulation (AM) using differential space-time block codes (DSTBC) in the presence of Rayleigh fading channel. A MIMO system, DSTBC can be simplified to be a multiple SISO (scalar) system with a diversity gain. A near-instantaneous signal-to-noise (SNR) ratio at the DSTBC receiver is used as a channel quality estimate. Using the channel quality, the system is able to choose a set of SNR thresholds that maximize throughput and keeps the target bit-error-rate (BER) for a given average transmitted SNR