Iterative Decoding of Serial Concatenated Differential Space-Time Block Coding under Unknown Fading Channels

Noncoherent BCJR algorithm, in which multiple symbol windowing is used to recover deterioration caused by channel phase noise, is proposed for single input and single output (SISO) systems in AWGN channels. In this article, we first apply noncoherent BCJR algorithm to multiple input and multiple output (MIMO) systems and generalize the algorithm from scalar to matrix based. In addition, we advance its competency from AWGN channels to Rayleigh fading channels and formulate corresponding branch metric. Based on our theoretical derivation, we propose noncoherent and non-CSI iterative decoding for serial concatenated single differential space-time block coding (SDST) and develop two types of decoding techniques using rectangular windowing (RW) and exponential decaying windowing (EDW), respectively. The efficiency of our proposed schemes is validated and compared via simulations.