Multiary EXIT chart with non-Gaussian distributed a priori information for UST signal-based turbo code

We propose a multiary unitary space-time signal-based turbo coding (UST-SB-TC) and decoding scheme for multiple-input multiple-output (MIMO) wireless communication systems. UST-SB-TC can make full use of the characteristics of rapidly fading channels in decoding and hence can give a better performance compared with bit-wise processing with the same code rate. Furthermore, we propose a novel multiary extrinsic information transfer (EXIT) chart with non-Gaussian distributed a priori information to analyze the convergence behavior, where we use “a priori signal-to-noise ratio (SNR)” to generate the a priori information. Specially, we demonstrate for the first time that when combined with effective channel coding, transmit diversity is not effective at low SNR with low code rate.