复杂环境下直扩信号侦察技术

摘要

侦察设备和目标存在径向速度变化导致接收信号存在多普勒频率变化，这将导致常规方法无法完成直接序列扩频信号（Direct—Sequency Spread Spectrum，DSSS）侦察。针对该情况研究了多普勒频率变化对常规检测方法的影响。提出一种针对多普勒频率变化时的直接序列扩频信号侦察技术，新技术消除了多普勒变化带来的影响，恢复了直接序列扩频信号的周期特征，能够在复杂环境低信噪比情况下完成直接序列扩频的检测和参数估计。理论分析和仿真验证表明该方法具有运算量小、精度高和易于硬件实现的特点。%The relative movement of reconnaissance device and targets introduces Doppler frequency change to received signals. Because of this,the conventional methods can not accomplish DSSS detection mission. Aiming at this point, the influence of Doppler frequency change rate on conventional method is researched. A new method for blind detection of DSSS signal is proposed, which eliminates the influence of Doppler frequency change rate and recovers the periodic character of DSSS signal. This method can detect the signal and estimate its parameters under complex environment. The analysis and simulation results show that this new method has lower computational complexity and higher detection probability, which is proper for hardware implement.