Abstract:

A new decoding method is introduced which is called sequential decoding，and a corresponding DHF  G fuction is proposed. In additive white Gaussion noise (AWGN) channel and frequency nonselective Rayleigh slowly fading channel, the error bit rate (EBR) performance in HF differential frequency hopping system is simulated as well as analyzed, and the results indicate that correlation between signal frequencys in HF differential frequencyhopping system makes the system obtain the capability of correcting error that results from faulty  hopping. For example, for a system with 4 available frequencies and 1 bit per hop, the P_b is 1e4 when the SNR is approximately 10 dB over AWGN channels, and the performance is improved up to 2.5 dB compared with the symbolbysymbol decoded method; while it is 1e3 when SNR is approximately 18 dB over Rayleigh fading channels, and the performance isimprovedup to 15 dB compared with the symbolbysymbol decoded method. So, compared with the symbol-by-symbol decoded method, it is better to use sequential decoding in HF differential frequency-hopping system.