数字喷泉技术在跳频通信中抗干扰性能研究

为提高跳频抗干扰性能,提出将Raptor码作为前向纠错码应用于跳频通信系统,其中Raptor码采用码率为0.95的规则LDPC码作为预编码,再级联LT码来实现.通过Matlab建模仿真实验,分析了跳频通信系统对抗宽带干扰以及部分频带干扰的性能.结果表明,宽带干扰环境下,在比特信干比为2.5dB时可以使误比特率低于10-3,得到17.6dB的性能提升;部分频带干扰环境下,在比特信干比为1.0dB时,可以将系统误比特率降低到10-3以下,得到16.8dB以上的性能提升.因此,用Raptor码作为跳频通信前向纠错码是可行的.

Research of Anti-Interference Performance of Digital Fountain Codes in Frequency Hopping Communication

To improve the anti-interference performance of frequency hopping (FH) communications, Raptor code is applied in the FH communication as a forward error correction (FEC) code in this work. The proposed Raptor code is composed of 0.95 rate of regular LDPC pre-code and the cascading Luby transform (LT) code. By modeling and experiments on Matlab platform, the anti-interference performance of the FH communication system in different interference channels was analyzed. The results are as follows. In broadband interference channels, provided that the bit SNR is 2.5 dB, the BER is lower than 10^-3 and the system performance would be improved by 17.6 dB. In partial-band interference channels, provided that the bit SNR is 1.0 dB, the BER is lower than 10^-3, the system performance would be improved by 16.8 dB. It could be concluded that it is feasible to apply the proposed Raptor codes in FH as the FEC code.