Design of structured LDPC codes with quasi-cyclic and rotation architecture

Quasi-cyclic low density parity check (LDPC) codes and rotation LDPC codes are investigated in this paper, based on which, a new class of well-structured LDPC codes are proposed. Additionally, for ease of coding, a dual-diagonal structure is applied to the parity-check matrices of those codes, which ensure that parity-check bits can be recursively calculated with linear computational complexity. With the rotating and cyclic shift structure, decoders can be effectively implemented with partially parallel architecture appeared in some literatures on QC-LDPC codes and other structured LDPC codes. Simulation results show that the proposed structured LDPC codes are feasible.