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.