研究了频谱交叠和目标运动情况下的去斜调频步进信号处理方法。在分析了宽带去斜信号步进频合成原理的基础上,提出了一种频谱交叠情况下的时域信号拼接算法和基于最小熵的速度补偿算法,在一帧去斜调频步进信号内同时实现带宽合成、高精度测速和目标尺寸估计。在跟踪系统提供的引导速度附近小范围内搜索不同速度补偿值对应的合成高分辨距离像波形熵,以最小熵对应的速度为目标速度估计,采用该速度对回波进行速度补偿实现带宽合成并提取目标径向尺寸。仿真分析表明,文中提出的算法效果优异,性能稳健,可同时完成去斜步进频信号带宽合成及高精度测速、尺寸估计等目标参数测量,非常适合于目标识别等实际应用。

The algorithms of the stretched chirp-step signal synthesizing and velocity compensation are researched in this paper. After analyzing its theory, a novel time domain signal synthesizing algorithm and the minimum entropy velocity compensation algorithm are proposed to solve the bandwidth synthesizing and accurate target parameters estimation within a stretched chirp-step signal burst. The minimum entropy velocity compensation algorithm searches the radial velocity in a small range around the guiding velocity to compensate the phase error induced by the target′s translation and calculates the corresponding HRRP′s entropy, selecting the HRRP with minimum entropy as the optimal result and the corresponding velocity as the target′s velocity estimation. Based on the optimal HRRP, the dimension of the target can be estimated accurately as well. Simulation results demonstrate that under common velocity accuracy and SNR situation, the algorithms work robustly by outputting correct HRRP of the target and its accurate velocity and dimension parameters simultaneously, which is very useful for the applications such as radar target recognition.

TN97