针对外辐射源雷达系统中弱目标回波信号淹没在强直达波、多径、干扰信号和噪声中的问题,提出一种基于循环平稳特性的弱目标回波信号盲抽取方法.该方法不需要参考通道,而是利用信号的谱线生成特性直接对回波通道信号进行抽取,通过迭代使输出信号中目标回波信号成分最大化,同时使其他信号和噪声成分最小化.与传统的外辐射源雷达目标回波信号获取方法相比,该方法不需要参考通道及杂波对消,既简化了接收机的结构,又减少了运算量.仿真实验验证了该方法的有效性.
To extract the weak echo signal buried in a strong direct signal,multipath signal,interfering signal and noise in passive radar systems,a new method is proposed based on cyclostationarity.The desired signal can be directly extracted from the echo channel without the reference channel based on the spectral line generating characteristics.Then,the component of the desired signal is maximized in an iterative way,while other signals and noise are minimized.Compared with the traditional methods,the proposed algorithm does not need the reference channel,which can simplify the structure of the receiver,and what's more,the computational burden is decreased.Simulation results verify the effectiveness of the proposed method.