误码条件下的LDPC码盲识别算法

A Recognition Algorithm for LDPC Codes of Blind in a Noisy Environment

为解决误码条件下信道编码校验矩阵难以逆向重建的问题,提出了一种新颖的LDPC码盲识别算法,简称迭代筛选(IS)算法。首先,由被截获数据构造含错矩阵,通过实施列消元运算获取其对偶向量;接着,利用校验向量判定准则从对偶向量中筛选出LDPC码的有效校验向量;进而再对被截获数据中的含错码组进行辨识和剔除;迭代进行以上操作,不断提高被截获数据内无误码码组的比例,直至将原问题退化为无误码时的简单场景;最终使用渐进行变换算法,实现LDPC码校验矩阵的稀疏化。仿真和实测均显示,IS算法对于802.16e、802.11n、DVB-S2、GJB7296、GB20600等公开标准均有效,能够在误码率不高于10^(-4)条件下的非合作场合实现LDPC码的盲识别,LDPC码校验矩阵获得了完整重建。

A novel recognition algorithm（called iterative screening,IS）for LDPC codes of blind is proposed to solve the problem that the parity-check matrix of Channel Coding is hard to reconstruct in a noisy environment.A matrix with the intercepted data is constructed,and then dual vectors of the matrix are obtained by using column elimination operation.Effective paritycheck vectors of the dual-space of the LDPC code are selected and error code blocks are recognized and deleted from the intercepted data.These steps are iteratively carried out until the original problem is reduced to a simple problem,i.e.,blind recognition of some error-free codes.The sparse parity check matrix is finally obtained by using Gradual Row Transformation.Simulation and experimental results show that the IS algorithm can apply to most LDPC standards,such as802.16 e,802.11 n,DVB-S2,GJB7296 and GB20600.It is able to be used in the non-cooperative context with the bit error rate less than 10^-4,and reconstructs the sparse parity check matrix of LDPC codes.