可快速编码的多码率原模图LDPC码设计

Design of multi-rate protograph LDPC codes with fast encoding

原模图LDPC码的实际应用涉及到两个问题:快速编码和编码复杂性.与其他LDPC码相比,原模图LDPC码的结构适合快速解码,但不一定能够实现快速编码.现有的原模图LDPC码的编码是根据生成矩阵进行编码,因其生成矩阵不是稀疏的,所以存在编码复杂性问题,这给编码器的硬件实现带来较大的困难.为了降低原模图LDPC码编码复杂度,本文提出一种可快速编码的多码率原模图LDPC码的设计,提出的多码率原模图LDPC码不存在4环,无低码重码,其快速编码算法能够降低编码复杂性,使编码器的硬件易于实现.在AWGN信道仿真结果表明,提出的可快速编码的多码率LDPC码的误码率性能和纠错性能优于GB20600 LDPC码.

The real application of protograph LDPC codes involves two problems： fast encoding and the encoding complexity.Protograph LDPC codes suit for fast decoding comparing with other LDPC codes,but protograph LDPC codes are not necessarily able to achieve fast encoding.The encoding of existing protograph LDPC codes is done by generate matrix,but the generate matrix of protograph LDPC codes is not sparse.Thus,protograph LDPC codes exists encoding complexity,which makes it difficult for encoder hardware implementation.In order to lower the encoding complexity of protograph LDPC codes,this paper proposes a design of multi-rate protograph LDPC codes with fast encoding;The proposed multi-rate protograph LDPC codes do not exist girth-4s;Furthermore,the fast encoding algorithms of the proposed multi-rate protograph LDPC codes can reduce encoding complexity and simplify encoder hardware.The simulation results in AWGN channels show that the BER and correct error ability performance of the proposed multi-rate protograph LDPC codes is much better than that of GB20600 LDPC codes.