喷泉码差分跳频系统在 AWGN 中抗部分频带干扰性能研究

摘要

In order to improve the performance of rejecting partial-band noise jamming,the Fountain code (FC)is introduced to the differential frenquency hopping (DFH)systems as the outer error correcting code in concatenated coding systems which can be called Fountain code-differential frenquency hopping (Fountain-DFH);The improvements against partial-band noise jamming over the additive white Gaussian channel (AWGN)by employing the Fountain code are investigated;The performance of Fountain-DFH is theoretically analyzed and numerically simulated with jammer state information (JSI)and no JSI.The total frequency of hopping in the simulation is 32,experimental results show that when exact JSI is available,the system is with 32 jamming-frequencies,the performance of SJR improves 2 dB to 2.5 dB compared with the uncoded system when P b is 10 -4 .Meanwhile,the performance improves 10 dB to 12 dB when jamming-frequencies is 1.When JSI is unavailable,a hopping training sequence estimation and decoding algorithm is proposed to acquire accurate JSI,which makes Fountain-DFH systems still have robust anti-jamming performance even without JSI.%为了改善差分跳频（differential frenquency hopping，DFH）系统抗部分频带干扰性能，提出一种将喷泉码（Fountain code，FC）应用于 DFH 的喷泉码差分跳频（Fountain code-differential frenquency hopping， Fountain-DFH）级联编码系统；在加性高斯白噪声信道（additive white Gaussian channel，AWGN）下研究其抗部分频带干扰性能的改善；对 Fountian-DFH 抗干扰性能在有精确干扰状态信息（jammer state information，JSI）和无精确干扰状态两种情况下进行了理论分析和数值仿真。仿真总频点数 M 为32，结果表明：当存在精确 JSI 信息时，干扰频点 n 为32点干扰，误码率为10－4情况下，Fountian-DFH 系统相对普通 DFH 系统信干比有2～2．5 dB 的性能改善；在干扰频点数 n 为1时有10～12 dB 的改进。当无 JSI 信息时，提出一种跳频训练序列的 JSI 估计译码算法，使 Fountian-DFH 系统较准确获取 JSI 信息，具有较强抗干扰能力。