一种DS/FH混合扩频的抗干扰波形设计方法

An Anti-interference Waveform Design Method of DS/FH Hybrid Spread Spectrum

现行的测控系统常采用直接序列扩频(DSSS)测控体制,实现相对简单,随着低截获概率(LPI)信号检测技术的不断发展,直接序列扩频测控系统面临着严重的威胁,抗干扰能力较差。针对此问题,提出了一种直接序列(DS)/跳频(FH)混合扩频的抗干扰波形设计方法。该方法采用大区域同步(LAS)码作为DS/FH混合扩频信号的扩频序列,并增加了载波跳变的功能。首先综合了2种方式的优点,对信号进行建模。然后通过模糊函数理论,结合DS/FH混合扩频信号自身特性,分析了信号的固有抗干扰性能。最后建立了3种常见的压制式噪声干扰模型,验证了DS/FH混合扩频信号的抗干扰效果。仿真结果表明,采用本文所提的波形设计方法,信号经匹配接收后信干比得到了良好的改善,满足在阻塞式干扰环境下的抗干扰需求,提高了测控系统的保密性以及抗干扰能力。

The current measurement and control system adopts the direct sequence spread spectrum(DSSS)measurement and control system,and the realization is relatively simple.With the continu-ous development of low intercept probability(LPI)signal detection technology,the DSSS measure-ment and control system faces a serious threat,and the anti-interference ability is poor.In order to solve this problem,this paper proposes a method of anti-interference waveform design for direct se-quence(DS)/frequency hopping(FH)hybrid spread spectrum.This method uses large area syn-chronized(LAS)code as the spread spectrum sequence of DS/FH mixed spread spectrum signals,and adds the function of carrier hopping.First,the advantages of two methods are combined to per-form signal modeling.Then the inherent anti-interference performance of DS/FH hybrid spread spectrum signal is analyzed based on the ambiguity function theory and its own characteristics.Fi-nally,three common suppressive noise jamming models are established to verify the anti-interfer-ence effect of DS/FH mixed spread spectrum signals.The simulation results show that,by using the waveform design method proposed in this paper,the signal-to-interference ratio of the signal is well improved after signal matching and reception,which meets the anti-interference requirements in the barrage jamming environment and improves the confidentiality and anti-interference ability of the measurement and control system.