This paper presents a simple yet effective decoding for general quasi-cyclic low-density parity-check （QC-LDPC） codes, which not only achieves high hardware utility efficiency （HUE）, but also brings about great me...This paper presents a simple yet effective decoding for general quasi-cyclic low-density parity-check （QC-LDPC） codes, which not only achieves high hardware utility efficiency （HUE）, but also brings about great memory block reduction without any performance degradation. The main idea is to split the check matrix into several row blocks, then to perform the improved mes- sage passing computations sequentially block by block. As the decoding algorithm improves, the sequential tie between the two-phase computations is broken, so that the two-phase computations can be overlapped which bring in high HUE. Two over- lapping schemes are also presented, each of which suits a different situation. In addition, an efficient memory arrangement scheme is proposed to reduce the great memory block requirement of the LDPC decoder. As an example, for the 0.4 rate LDPC code selected from Chinese Digital TV Terrestrial Broadcasting （DTTB）, our decoding saves over 80% memory blocks com- pared with the conventional decoding, and the decoder achieves 0.97 HUE. Finally, the 0.4 rate LDPC decoder is implemented on an FPGA device EP2S30 （speed grade -5）. Using 8 row processing units, the decoder can achieve a maximum net throughput of 28.5 Mbps at 20 iterations.展开更多
In this paper,a family of rate-compatible(RC) low-density parity-check(LDPC) convolutional codes can be obtained from RC-LDPC block codes by graph extension method.The resulted RC-LDPC convolutional codes,which are de...In this paper,a family of rate-compatible(RC) low-density parity-check(LDPC) convolutional codes can be obtained from RC-LDPC block codes by graph extension method.The resulted RC-LDPC convolutional codes,which are derived by permuting the matrices of the corresponding RC-LDPC block codes,are systematic and have maximum encoding memory.Simulation results show that the proposed RC-LDPC convolutional codes with belief propagation(BP) decoding collectively offer a steady improvement on performance compared with the block counterparts over the binary-input additive white Gaussian noise channels(BI-AWGNCs).展开更多
为满足深空通信系统对低延时、低复杂度、高可靠性信道编译码的需求,提出一种基于国际空间数据系统咨询委员会(Consultative Committee for Space Data Systems,CCSDS)通信协议中低密度奇偶校验(low density parity check,LDPC)码的自...为满足深空通信系统对低延时、低复杂度、高可靠性信道编译码的需求,提出一种基于国际空间数据系统咨询委员会(Consultative Committee for Space Data Systems,CCSDS)通信协议中低密度奇偶校验(low density parity check,LDPC)码的自适应译码算法。该算法通过检测当前信道条件,自适应设置提前停止策略,降低译码延时;对校验矩阵做评估,自适应选择译码修正系数,提升译码性能。仿真结果表明,该算法最多能够降低平均迭代次数41%,在误码率10^(-5)的条件下提升译码性能0.2 dB。该算法几乎不增加译码处理的复杂度,且适用于多种LDPC码,具有工程实践性。展开更多
基金Science and Technology on Avionics Integration Laboratory and Aeronautical Science Foundation of China (20115551022)
文摘This paper presents a simple yet effective decoding for general quasi-cyclic low-density parity-check （QC-LDPC） codes, which not only achieves high hardware utility efficiency （HUE）, but also brings about great memory block reduction without any performance degradation. The main idea is to split the check matrix into several row blocks, then to perform the improved mes- sage passing computations sequentially block by block. As the decoding algorithm improves, the sequential tie between the two-phase computations is broken, so that the two-phase computations can be overlapped which bring in high HUE. Two over- lapping schemes are also presented, each of which suits a different situation. In addition, an efficient memory arrangement scheme is proposed to reduce the great memory block requirement of the LDPC decoder. As an example, for the 0.4 rate LDPC code selected from Chinese Digital TV Terrestrial Broadcasting （DTTB）, our decoding saves over 80% memory blocks com- pared with the conventional decoding, and the decoder achieves 0.97 HUE. Finally, the 0.4 rate LDPC decoder is implemented on an FPGA device EP2S30 （speed grade -5）. Using 8 row processing units, the decoder can achieve a maximum net throughput of 28.5 Mbps at 20 iterations.
基金the National Natural Science Foundation of China(Nos.61401164,61471131 and 61201145)the Natural Science Foundation of Guangdong Province(No.2014A030310308)
文摘In this paper,a family of rate-compatible(RC) low-density parity-check(LDPC) convolutional codes can be obtained from RC-LDPC block codes by graph extension method.The resulted RC-LDPC convolutional codes,which are derived by permuting the matrices of the corresponding RC-LDPC block codes,are systematic and have maximum encoding memory.Simulation results show that the proposed RC-LDPC convolutional codes with belief propagation(BP) decoding collectively offer a steady improvement on performance compared with the block counterparts over the binary-input additive white Gaussian noise channels(BI-AWGNCs).
文摘为满足深空通信系统对低延时、低复杂度、高可靠性信道编译码的需求,提出一种基于国际空间数据系统咨询委员会(Consultative Committee for Space Data Systems,CCSDS)通信协议中低密度奇偶校验(low density parity check,LDPC)码的自适应译码算法。该算法通过检测当前信道条件,自适应设置提前停止策略,降低译码延时;对校验矩阵做评估,自适应选择译码修正系数,提升译码性能。仿真结果表明,该算法最多能够降低平均迭代次数41%,在误码率10^(-5)的条件下提升译码性能0.2 dB。该算法几乎不增加译码处理的复杂度,且适用于多种LDPC码,具有工程实践性。
