Searching for Large Girth Quasi-Cyclic Spatially Coupled LDPC Codes

摘要

In this paper, we present an approach which searches the large girth quasi-cyclic (QC) spatially-coupled (SC) low-density parity-check (LDPC) codes by lifting the coupled protographs matrices. At first, a set of performance measures is employed to facilitate the construction of protographs. Then the QC lifting procedure searches the large girth base matrices for SC-LDPC based on the protographs. A systematic design of SC-LDPC code with stringent structural constraint condition makes the encoder more efficient. Furthermore, it is easy to synchronize the process of encoding and sliding windowed decoding by using grouping period time-varying sub-matrices. We find that the performance the QC-SC-LDPC is superior that of the block QC-LDPC, and the QC-SC-LDPC has lower complexity as well as delay of than block QC-LDPC.