基于FFT分析技术的连续波测速雷达在靶场得到广泛应用,FFT对多普勒频移的物理分辨率取决于所分析的信号长度,针对FFT对于雷达速度分辨率存在的局限性,提出了线性调频Z变换方法,在单位圆上计算CZT,计算时的输入点数和输出点数可以不相等,在不增加信号长度条件下可“细化”频谱,仿真实验表明,CZT对雷达速度的分辨率优于FFT,将该算法应用于测速雷达可以提高多目标分辨能力。

The FFT analytic technique based continuous-wave Doppler radars are extensively used in test range, the true resolution of Doppler shift is dependent on the analyzed signal length by FFT. Concerning the problem that the FFT has limitation of velocity resolution, the CZT calculated on unit circle was proposed, in which the input signal length is unequal with the output signal length, the frequency spectrum can be refined without increasing the radar signal length. Simulation results show that the CZT is superior to the FFT in velocity resolution, the ability to distinguish multiple targets is enhanced by the proposed algorithm.