编码协作系统准循环重复累积码的联合设计与性能分析

重复累积(RA)码是一种特殊结构的低密度奇偶校验(LDPC)码,不仅具有LDPC码的优点,还能实现差分编码。针对LDPC编码协作系统编码复杂度高、时延长的问题,该文引入准循环RA(QC-RA)码,推导出信源节点和中继节点采用的QC-RA码对应的联合校验矩阵,基于公差构造方法设计该联合校验矩阵,并证明该方法设计的联合校验...

Joint Design of QC-RA Codes and Performance Analysis of Coded Cooperation

Repeat Accumulate (RA) code is a special kind of Low Density Parity Check (LDPC) code, which not only has the advantages of LDPC code, but also realizes differential encoding. To solve the problems of high encoding complexity and long encoding delay of LDPC-coded cooperative system, Quasi-Cyclic RA (QC-RA) code is introduced. Firstly, a joint parity check matrix corresponding to the QC-RA codes adopted by the sources and relays is deduced; Secondly, the joint check matrix is designed based on the Common Difference Construction (CDC) method, and it is proved that the joint check matrix designed by the CDC method does not have short cycles with girth-4 or girth-6. Theoretical analysis and simulation results show that the system achieves better Bit Error Rate (BER) performance than the corresponding point-to-point system under the same conditions. The simulation results also demonstrate that the multi-source multi-relay coded cooperation with CDC constructed QC-RA code can obtain higher coding gain than that with generally constructed QC-RA code or Z-type constructed QC-RA code.