An Anti-Jamming Technique Based on Correlated Pre-Windowing Filter in DFH Receivers

The DFH (Differential Frequency Hopping) technology brings high performances for HF (Frequency Hopping) communication systems. Symbol-by-symbol detection has been widely used in DFH systems, but the anti-jamming (AJ) performance is poor. In order to achieve better AJ performance, a novel anti-jamming technique based on Correlation Pre-Windowing Filter (CPWF) on frequency domain is proposed in this paper. The technique is performed on the basis of the frequency transition function (FTF), and all of the wideband receiving frequencies can be limited to several frequencies which may be used in the next Frequency hopping. Meanwhile, the symbol error propagation can be eliminated by combing prewindowing filter and comb filter. The symbol error rate (SER) of the DFH receiver with the technique is simulated and analyzed over additive white Gaussian noise (AWGN) channels. The results show that the DFH receiver with the technique can improve the AJ ability and enhance SER performance over AWGN channels effectively. Simultaneously, the receiver complexity is reduced significantly due to DFH signal processing on frequency domain. Hence the Anti-jamming Technique will be of great value to engineering applications.