Parallel Implementation of GPU-Based LDPC Enhanced Quasi-Maximum Likelihood Decoder
KONG Feiyue, JIANG Xueqin, WAN Xuefen, CHEN Sijing, CUI Jian, YANG Yi
Abstract
The Enhanced Quasi-Maximum Likelihood(EQML) decoder has better decoding performance for short Low Density Parity Check(LDPC) codes than traditional Belief Propagation(BP) decoder,and can meet the high reliability requirements of 5G mobile communication.However,its decoding speed is greatly reduced due to its complex computational structure.To address the problem,this paper proposes a parallel acceleration scheme based on Graphics Processing Unit(GPU) for EQML decoder.The scheme compresses and stores the parity check matrix of irregular LDPC codes,and resorts the traditional BP decoding algorithms to maximize the utilization of threads in Kernel.Then parallel decoding is implemented for multi-code words in each stage of reprocessing,so as to realize memory access optimization and parallel decoding of streams.Experimental results show that the GPU-based EQML decoder improves the speed by two orders of magnitude compared with the CPU-based decoder,while keeping the error correction performance.