脉冲多普勒雷达杂波信号的实时重构方法研究

Real-Time Signal Reconstruction for Pulse Doppler Radar Clutter

针对脉冲多普勒雷达信号处理机在杂波半实物仿真时由重构算法带来的噪声应低于主瓣杂波 60dB这一特殊要求 ,提出了一种给定功率谱的杂波产生方法 ,即先将功率谱转换为矢量频谱 ,并进行相位随机化和傅里叶反变换 ,然后对得到的一系列时域数据组加窗、搭接 ,保证随机数据的数学期望和方差连续 ,从而得到缓变的非平稳杂波信号 .仿真结果表明 :采用此方法得到的杂波信号与简单组合时域数据组得到的杂波信号相比 ,信噪比可由 30dB提高到 60dB .

For pulse Doppler radar to detect the target signal which is spectrally separated from clutter, it is required in missile hardware-in-the-loop that the noise resulted by clutter reconstruction architecture should be 60 dB lower than the main-lobe clutter. Because of the restriction, a new method of clutter reconstruction is proposed, which includes conversion from power spectrum to vector spectrum, randomization of phase, inverse Fourier transform, and then windowing and overlapping the series time domain sequence, so as to guarantee the continuous expectation value and variance of random sequence. Simulation results demonstrate that the ratio of signal to noise increases from 30 dB to 60 dB by applying this method.