Performance comparison between differential frequency hopping and fast frequency hopping

Abstract

Differential frequency hopping (DFH) is a frequency-hopping communication system with memory. The minimum sequence error method is proposed as the frequency sequence estimation algorithm. This algorithm can effectively reduce the illegal frequency transfer states through a searching method called the maximum-likelihood detection. The algorithm can improve the performance of DFH as well. In a fast frequency-hopping (FFH) system, the frequency-hopping rate is higher than the symbol rate, say 3 hops per bit, 5 hops per bit or 7 hops per bit.

In this report, the literature review and the background are the prerequisite in understanding the whole project. They include the definitions and principles of DFH, FFH, non-coherent detection binary frequency shift keying (BFSK), additive white Gaussian noise (AWGN), Rayleigh selective fading channels, signal-to-noise ratio (SNR), signal-to-jamming ratio (SJR) and bit-error rate (BER). With the knowledge of those terms and applications, it is easier in building the simulation model of FFH and DFH. The simulation models of FFH and DFH systems are designed in this report. The performance of FFH and DFH systems is compared. The results are obtained and discussed in the report.