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Designing Frequency Transition Function of Differential Frequency Hopping System

Differential frequency hopping (DFH) communication is a new technology for reliable high data rate transmission. The frequency transition function which combines frequency hopping pattern controlling and modulation is one of the key technologies in DFH. Traditional frequency transition function construction methods have the drawback that the free distance is confined to the number of frequencies in the hopping pattern. The improvement of the system performance is at the price of system band. In this paper, an innovative frequency transition function is proposed . The free distance of the new frequency transition function was analyzed and it is no longer confined to the frequency number. The upper bound of bit-error-rate over Nakagami-m channels was analyzed and validated by simulation. Meanwhile the performance comparison between the improved frequency transition and the traditional one was investigated by simulation which shows that considerable improvement can be achieved.