Polar-Coded MIMO Systems

Abstract

To more efficiently realize the coded multiple-input multiple-output (MIMO) transmission and improve the system performance, in this paper, we propose a framework combining the polar coding and the MIMO technique, namely the polar-coded MIMO (PC-MIMO) systems. The MIMO transmission will be recognized from the novel perspective of channel polarization. Combining the polar coding and modulation, the MIMO transmission channel is decomposed into a series of bit-polarized channels under the three-stage channel transform, that means the antenna $\rightarrow$ modulation $\rightarrow$ bit partition. Based on this generalized channel polarization transform, the PC-MIMO systems allow a joint optimization of polar coding, signal modulation, and MIMO transmission. Specifically, for the first-stage transform, we propose two schemes, namely sequential antenna partition (SAP) and parallel antenna partition (PAP). For the SAP-based PC-MIMO, by using the successive detection of the MIMO signal, the antenna data streams are sequentially decomposed and polarized. In addition, a joint multistage detection and decoding scheme is proposed to combine the multilevel coding method in the second- and third-stage transforms to fully utilize the multiplexing gain and the coding gain. In contrast, the PAP-based PC-MIMO exploits the channel polarization of parallel MIMO detection and concatenates the bit-interleaved coded modulation structure in the second- and third-stage transforms to reduce the processing latency. The simulation results over the MIMO channel with the Rayleigh fast fading show that the proposed PC-MIMO schemes can well outperform the turbo-coded MIMO schemes utilized in many mainstream communication systems.