LT码和q-LDPC码级联方案在深空通信中的应用

该文针对深空通信对长纠删码的需求，提出了LT (Luby Transform)码和q-LDPC码的级联方案。在综合考虑性能和复杂度的情况下，选取8-LDPC码和8PSK的级联作为等效的删除信道，长度选择灵活、编译码简单的LT码实现纠删功能。文中设计了两种短8-LDPC码，并对整个级联系统的纠错性能进行了仿真。仿真结果表明8-LDPC码的性能优于信源信息速率和码率相同的二进制LDPC码，级联系统在等效包删除概率不超过0.1时，系统误比特率以概率1趋于0。

Application of the Concatenation of q-LDPC and Luby Transform Codes in Deep Communications

A concatenated scheme of Luby Transform (LT) code and q-ary Low Density Parity Check (q-LDPC) code is proposed for the requirement of deep space communications long erasure correcting codes. Considering the performance and complexity of the concatenated system, 8PSK modulation coded with 8-LDPC codes over AWGN channels is chosen to act as equivalent erasure channels and LT codes with flexible code length and low encoding and decoding complexity correct erasure errors. Two short 8-LDPC codes are designed. Simulations are conducted on the performance of packet error of two 8-LDPC codes and the overall performance of the concatenated system. Simulation results show that both the 8-LDPC codes outperform the corresponding binary LDPC (B-LDPC) codes with the same source rate and code rate and the bit error rate of the concatenated system is null with probability 1 when the packet erasure rate is not more than 0.1.