Nonbinary LDPC-Coded Modulation System in High-Speed Mobile Communications

As a class of capacity-approaching codes, nonbinary low-density parity-check (LDPC) codes have attracted much attention because of noticeable performance. Nonbinary LDPC-coded modulation systems which have excellent performance for high-spectral efficiency transmission are also potential schemes in the future communication system. In this paper, we propose a new construction method of quasi-cyclic nonbinary LDPC codes. Furthermore, a comparative study about the performance of various coded systems over the AWGN channel and the high-mobility channel is performed on turbo codes in LTE communications and LDPC codes in 5G standard. Simulation results show that the nonbinary LDPC-coded modulation system is effective for improving the performance of wideband wireless communication systems with orthogonal frequency division multiplexing in the high-mobility scenario.