关键词: 准循环低密度奇偶校验码（QC-LDPC）, 直接序列扩频（DSSS）, Moore-Penrose逆, 改进型Logistic映射, 通用数据链

Abstract: A cooperated narrow-band jamming suppression scheme is proposed based on Quasi-Cyclic Low Density Parity Check codes（QC-LDPC） and chaotic direct sequence spread spectrum for improving the data transmitting in the low SNR with the different jamming. The QC-LDPC encodes are designed through the Moore-Penrose inverse and the full rank decomposition based on the parity check matrix. The inverse transform for identity matrix and direct product are used for constructing the parity check matrix. The performance of chaotic spread spectrum sequences, produced from improved Logistic MAP, is analyzed and verified by simulations. Simulation results demonstrate that the scheme can bring 8.2 dB SNR gain comparing to current standard when the jamming-to-signal ratio is 20 dB.

Key words: Quasi-Cyclic Low Density Parity Check codes（QC-LDPC）, Direct Sequence Spread Spectrum（DSSS）, Moore-Penrose inverse, improved Logistic MAP, Common Data Link（CDL）