Anti- Partial Band Nosie Jamming Performance Analysis Of FH/MFSK System

Frequency Hopping(FH) technology is a spectrum spreading technology, which has better performance in anti- intercepting, anti- fading and anti- jamming,paticularly in barrage jamming and track jamming. The carrier frequency of frequency hopping communication will rapidly switch among all the frequencies, which may cause phase discontinuity, so frequency hopping communication is usually combined with Multiple-Frequency-shift Keying(MFSK) modulation. In conventional analysis of anti-Partial-Band-Nosie Jamming(PBNJ) of FH/MFSK system, the minimum jamming bandwidth is the bandwidth of MFSK. In this thesis, the minimum resolution bandwidth is set to 1/M of the MFSK signal band width. Theoretical derivation of the anti-jamming performance for FH/MFSK system is conducted in different sweeping rates and channels. The results show that the narrower the bandwidth interference is, the greater interference minimum resolution bandwidth deteriotes the Bite Error Rate(BER) of system.There are five chapters in this thesis. Chapter 1 gives introduction and research status of the Frequency Hopping technology. In the second chapter, we introduce the model of FH/MFSK and PBNJ system, derive the worst PBNJ and analyze theoretical and computer-simulated BER perforamance of the system in Additive White Gaussian Noise(AWGN) channel. A non- integer PBNJ model whose minimum resolution bandwidth is set to 1/M of the MFSK signal bandwidth is introduced in chapter 3 and respective performances in AWGN channel, Rayleigh channel and Rice channel are given; in chapter 4 we analyze the performance of FH/MFSK system with convo lutional encoding in different channels(none-background noise channel, AWGN channel and Rayleigh channel) with PBNJ. At last we conclude the whole paper and point out future researches.