Design of RC-LDPC codes and its application in codes SC-FDE systems

Abstract

This paper proposes a new scheme of the rate compatible low-density parity-check (RC-LDPC) coded single carrier-frequency domain equalization (SC-FDE) system where RC-LDPC codes are combined with SC-FDE modulations. To construct a class of different RC-LDPC codes, we take advantage of a base matrix constructed by the progressive edge growth (PEG) algorithm. A special code matrix structure is used and modified to meet requirements of the different code rate. In addition, a pseudorandom sequence instead of traditional cyclic prefix (CP) is proposed to estimate the channel noise variance for LDPC decoding. The simulation results show that the modified RC-LDPC codes have better performance than that of current method and the RC-LDPC coded SC-FDE system obtains better performance compared with uncoded SC-FDE system.