The non-binary(NB) Irregular Repeat Accumulate(IRA) codes, as a subclass of NB LDPC codes, potentially have an excellent error-correcting performance. They are also known to provide linear complexity of encoding, but ...The non-binary(NB) Irregular Repeat Accumulate(IRA) codes, as a subclass of NB LDPC codes, potentially have an excellent error-correcting performance. They are also known to provide linear complexity of encoding, but the basic encoding method with the serial rate-1 accumulator significantly limits the encoder throughput. Then the objective of the research presented in this paper is to develop an encoding method pro- viding significantly increased throughput of an NB-IRA encoder altogether with a flexible code construction methods for the structured(S-NB-IRA) codes eligible for the proposed encoding method. For this purpose, we reformulate the classic encoding algorithm to fit into the partial parallel encoder architecture. We propose the S-NB-IRA encoder block diagram and show that its estimated throughput is proportional to the submatrix size of the parity check matrix, which guarantees a wide complexity- throughput tradeoff. Then, in order to facilitate the S-NB-IRA coding systems design, we present a computer search algorithm for the construction of good S-NB-IRA codes. The algorithm aims at optimizing the code graph topology along with selecting an appropriate non-binary elements in the parity check matrix. Numerical results show that the constructed S-NB-IRA codes significantly outperform the binary IRA and S-IRA codes, while their performance is similar to the best unstructured NB-LDPC codes.展开更多
针对复杂环境中通信系统误码率高和硬件实现复杂度高的问题,提出基于正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)时域差分和16进制幅度差分相移键控(16 Multilevel Differential Amplitude and Phase Shift Keying,...针对复杂环境中通信系统误码率高和硬件实现复杂度高的问题,提出基于正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)时域差分和16进制幅度差分相移键控(16 Multilevel Differential Amplitude and Phase Shift Keying,16DAPSK)调制联合低密度奇偶校验码(Low Density Parity Check Code,LDPC)软译码的通信方案。充分考虑了差分调制对抗多径干扰的能力,分别通过单数据多位宽移位寄存器方案、查找表的方式以及公式法实现LDPC编码、16DAPSK调制以及16DAPSK软解调。仿真结果证明了该方案在误码性能和资源节省方面的有效性。展开更多
低密度奇偶校验(Low-Density Parity-Check,LDPC)码是第五代移动通信技术(5th Generation Mobile Communication Technology,5G)系统采用的信道编码技术之一,用于业务信道高速数据传输,具有很强的抗干扰能力和纠错能力。5G-LDPC码编译...低密度奇偶校验(Low-Density Parity-Check,LDPC)码是第五代移动通信技术(5th Generation Mobile Communication Technology,5G)系统采用的信道编码技术之一,用于业务信道高速数据传输,具有很强的抗干扰能力和纠错能力。5G-LDPC码编译码在嵌入式平台的实现是一个值得关注的研究方向。CEVA-XC4500数字信号处理(Digital Signal Processing,DSP)芯片具有极低功耗、高密度计算、集成了超长指令字(Very Long Instruction Word,VLIW)和单指令多数据(Single Instruction Multiple Data,SIMD)矢量功能的特点。针对CEVA-XC4500 DSP矢量汇编指令和内联指令集的特点,提出一系列针对5G-LDPC码编码的代码优化方法,使其满足5G-LDPC码编码工程应用指标要求。仿真结果表明,优化后的5G-LDPC码编码在CEVA-XC4500 DSP内核上表现良好,中长块编码吞吐率超过100 Mb/s、核心矩阵吞吐率超过1 Gb/s,最大吞吐率达到250 Mb/s、最大核心矩阵吞吐率达到1.6 Gb/s。如果CEVA-XC4500 DSP芯片的最大数据位宽将来能进一步增大,吞吐率可以做得更好。该5G-LDPC码编码的代码优化方法为其他信道编码在类似嵌入式平台的实现提供了参考。展开更多
基金supported by the Polish Ministry of Science and Higher Education funding for statutory activities (decision no. 8686/E-367/S/2015 of 19 February 2015)
文摘The non-binary(NB) Irregular Repeat Accumulate(IRA) codes, as a subclass of NB LDPC codes, potentially have an excellent error-correcting performance. They are also known to provide linear complexity of encoding, but the basic encoding method with the serial rate-1 accumulator significantly limits the encoder throughput. Then the objective of the research presented in this paper is to develop an encoding method pro- viding significantly increased throughput of an NB-IRA encoder altogether with a flexible code construction methods for the structured(S-NB-IRA) codes eligible for the proposed encoding method. For this purpose, we reformulate the classic encoding algorithm to fit into the partial parallel encoder architecture. We propose the S-NB-IRA encoder block diagram and show that its estimated throughput is proportional to the submatrix size of the parity check matrix, which guarantees a wide complexity- throughput tradeoff. Then, in order to facilitate the S-NB-IRA coding systems design, we present a computer search algorithm for the construction of good S-NB-IRA codes. The algorithm aims at optimizing the code graph topology along with selecting an appropriate non-binary elements in the parity check matrix. Numerical results show that the constructed S-NB-IRA codes significantly outperform the binary IRA and S-IRA codes, while their performance is similar to the best unstructured NB-LDPC codes.
文摘针对复杂环境中通信系统误码率高和硬件实现复杂度高的问题,提出基于正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)时域差分和16进制幅度差分相移键控(16 Multilevel Differential Amplitude and Phase Shift Keying,16DAPSK)调制联合低密度奇偶校验码(Low Density Parity Check Code,LDPC)软译码的通信方案。充分考虑了差分调制对抗多径干扰的能力,分别通过单数据多位宽移位寄存器方案、查找表的方式以及公式法实现LDPC编码、16DAPSK调制以及16DAPSK软解调。仿真结果证明了该方案在误码性能和资源节省方面的有效性。
