从傅里叶望远镜接收信号中获取目标速度的方法

摘要

The signals received by Fourier telescopy are analyzed and demonstrated to contain not only image information but also two-dimensional velocity information of the measured target.The velocities on each component can be calculated by the periodic signal frequencies that can be extracted from received signals.Then the two-dimension velocity is composited.The frequency of the signal is extracted by fast Fourier transform analysis for coarse frequency estimate,and by ratio frequency correction algorithms using Hanning window for precise frequency correction.Simulation is made to measure the flight velocity of the missile by Fourier telescopy.The result shows that the target velocity acquired by this method has almost no error without noise,while it has relatively high precision with noise when SNR is higher than 5 dB.The velocity acquisition method from receiving signal of Fourier telescopy is demonstrated to have high precision,a good anti-noise property and to be theoretically feasible.%分析了傅里叶望远镜接收信号,结果表明,接收信号中不仅包含了被测目标的图像信息,还包含了目标的二维速度矢量信息.通过提取接收周期信号的频率可以推算出目标各分量的速度,从而得到二维速度矢量.信号频率的提取采用快速傅里叶变换分析进行频率粗估计,频率精确校正采用加Hanning窗的比值校正法.仿真了利用傅里叶望远镜测量导弹飞行速度.结果表明:在无噪声影响下,利用该方法获取的目标速度几乎无误差；存在噪声时,若接收信噪比高于5 dB,测量的目标速度精度高于0.02％.说明从傅里叶望远镜接收信号中获取目标速度的方法精度高、抗噪性好,理论上是可行的.