Nonbinary ldpc-coded probabilistic shaping scheme for MIMO systems based on signal space diversity

This paper first describes a binary Low-Density Parity-Check (LDPC)-coded Probabilistic Shaping (PS) scheme for Multiple-Input Multiple-Output (MIMO) systems based on Signal Space Diversity (SSD). Second, a Nonbinary (NB) LDPC-coded PS scheme for MIMO systems based on SSD is proposed. The first scheme can be used to obtain a shaping gain, whereas the second can also realize a coding gain. The theoretical average mutual information of the optimized rotated quadrature amplitude modulation constellations is analyzed and the simulated error performance with 2 x 2 and 4 x 4 MIMO schemes is investigated. The theoretical average mutual information analysis and simulation results show that the proposed NB LDPC-coded PS scheme for MIMO systems based on SSD is reliable and robust, and is therefore suitable for future wireless communication systems.