采用傅里叶拟合的双天线信号端点识别方法

Dual-Antenna Signal Endpoint Identification Method with Fourier Fitting

某型双天线模式的应答式弹道导弹在飞行过程中为维持较高的定向性,通常在平动的同时伴有自旋运动。其自旋过程中天线的轮序切换会造成信号微多普勒频率的阶跃,不利于信号模型描述与后期数据处理分析。基于微多普勒阶跃端点与双天线轮序切换节点相互对应的原理,通过双天线信号的差分处理,获得信号端点的粗信息,并采用傅里叶曲线拟合对所得信息进行平滑处理,获得精确端点信息,实现双天线信号的双路分离,进而为单天线信号中频率阶跃的支路处理提供信号基础。仿真与实测结果表明,该方法可实现端点信息的提取,其相对误差均小于0.5%。

In order to maintain a high directivity during the flight,a certain type of the dual-antenna mode responsive ballistic missiles are usually accompanied by spin motion in translation. The steps of the microDoppler frequency will be caused by the switching of the dual-antenna in the spin,which is unfavorable to the signal model description and the data analysis. Based on the principle which the steps of the microDoppler frequency and the dual-antenna signals correspond to each other,the rough information of the signal endpoint is obtained by the differential processing of the dual antenna signal,and the information is smoothed by the Fourier curve fitting which the accurate endpoint information is obtained. Thus the double antenna signal is separated,and then the signal basis for the branch processing of the frequency step of the single antenna signal is provided. The simulation and experimental results show that this method could extract the endpoint information,and the relative error is less than 0. 5%.