调频步进雷达目标抽取算法及系统参数设计

伪峰、抽取损失和多普勒耦合时移是影响线性调频步进信号应用的重要问题.本文分析了传统目标抽取算法中静止伪峰和运动伪峰的产生机理,给出了避免这两种伪峰出现的条件.为了降低抽取损失,本文提出了基于距离像最大1范数搜索的移位抽取算法,该算法通过搜索在不同移位量下抽取后的目标距离像的最大1范数,确定最佳的移位量,并把该移位量对应的抽取结果作为最终的目标距离像,从而避免了运动伪峰和抽取损失,同时校正了距离像的多普勒耦合时移.文中进一步分析了搜索算法的应用条件,并给出了系统参数的设计方法.通过对点目标和延展目标的仿真,证明了该算法的可行性.

Target Extracting Algorithm and System Parameter Design in Stepped Frequency Modulated Radar

Spurious peaks,extracting loss and doppler-coupling shift usually effect the application of the linearly modulated stepped frequency (LMSF) greatly.The mechanism of the still and moving spurious emergence in traditional target extracting algorithm is analyzed in the paper,which also presents the conditions for avoiding the appearance of the two kinds of spurious peaks.In order to lower the extracting loss,the paper describes a shift-extracting algorithm,which based on searching the maximum norm 1 of the range profile extracted by different shift quantity to fix on the optimum shift quantity,and then the final range profile can be obtained with the optimum shift quantity.Accordingly the moving spurious and extracting loss can be avoided,at the same time the doppler-coupling shift of the range profile is corrected.Moreover the paper analyses the application condition of this searching algorithm,and gives the design method for system parameters.The simulations on the point target and extended target testify the feasibility of the algorithm.