多频干扰下混合DS-SFH/MSK扩频系统性能分析

Performance analysis of hybrid DS-SFH/MSK SS system in the presence of multitone jamming

分析了相干MSK跳频调制的混合直接序列-慢跳频（DS－SFH）扩频信号在部分频带多频干扰和加性白高斯噪声下的性能．假设直接序列扩额后的信号带宽等于跳频频隙间隔，在此条件下推导了系统的误比特率公式，评价了在最恶劣干扰条件下系统的性能．分析中改变系统参数如DS/SFH混合比、干扰频点数、信噪比及干信比，结果表明，在某些情况下，在慢跳频系统中加入直扩成分，在不增加系统总带宽的条件下，可以有效地改善系统对抗部分频带多频干扰的能力．

This paper studies the performance of hybrid DS-SFH spread spectrum(SS) signal in the presence of partial band multitone jamming and Additive White Gaussian Noise. MSK is employed as m spread spectrum modulation. A DS-spread spectrum signal bandwidth is equal to the FH slot spacing. An equation for the bit error rate (BER) is developed. Performance is evaluated , assuming the worst case jamrner strategy. The analysis is performed for various system paraxnters such as a DS/SFH hybrid ratio, the number of jamming tones, a signal-to-noise ratio,and jamming-to-signal ratio. It is shown that, in some cases, the addition of DS spreading to an FH system, without increasing the total system banawidth, can significanily improve the system's resistance to partial band multitone Jamming.