机载雷达目标空时参数快速估计方法

针对机载雷达动目标空时参数估计中常用的基于最大似然准则的参数搜索方法计算量过大的问题,提出了一种新的目标空时参数快速估计方法.该方法首先对机载雷达阵列回波信号做降维的空时自适应处理,对滤波输出最大的多普勒单元在空域取3个不同方向的导向矢量做空域滤波,得到3个不同的自适应权矢量和输出响应,再利用这些权矢量和输出响应,用多项式求根方法得到目标的空域频率,然后利用多普勒频率滤波响应主瓣附近的3个频率的输出,依据二阶近似求解极值得到目标的多普勒频率最大似然估计值.仿真实验表明,该方法在保证估计精度与参数搜索方法相同的情况下,计算量能够减小到参数搜索方法的1/100.

A Fast Algorithm to Estimate Space-Time Parameters of Airborne Radar Target

A novel and fast algorithm is proposed to reduce the computation cost of the common grid searching method in estimating spacial-time parameters of airborne radar targets.The echo signal data from airborne radar array are processed by the dimension reduction spacial-time adaptive processing(STAP) method.Spacial filtering to the Doppler channel with maximal filter output is performed to get three different space angle steer vectors.Then,the spacial frequency is estimated by finding the roots of a polynomial which is constructed utilizing the three adaptive weights and outputs.The Doppler frequency is estimated using the filter outputs of three Doppler channels in the main lobe of the filter response curve and from the peak of the second-order response curve.Simulation results show that the computational cost of the proposed method is 1/100 of that of the grid searching method with the same estimation accuracy.