方位频域滤波的机场毫米波雷达干扰抑制方法

强散射目标距离旁瓣造成的干扰, 严重影响机场跑道异物(foreign object debris, FOD) 毫米波雷达对微弱目标的检测。针对该问题, 本文基于信号频谱分布特点, 即静止目标信号的方位谱具有窄带特性, 而旁瓣干扰信号的方位谱是宽带的, 提出在方位向进行信号频域滤波的干扰抑制方法。首先在距离向使用窗函数加权方法处理, 方位向通过傅里叶变换到频域, 利用提前标定和构建的窄带带通滤波器进行滤波, 最后再变换回时域。与其他方法相比, 该方法能够在有强散射环境下获得较好的干扰抑制效果, 提高微弱目标的信杂比。93 GHz FOD雷达实测数据处理结果验证了所提方法的正确性和有效性。

Interference suppression method based on azimuth frequency domain filtering for airport millimeter-wave radar

Strong scattering target can easily produce range side-lobe interference which seriously affects the detection of the weak target by the foreign object debris (FOD) millimeter-wave radar on the airport runway. For this problem, this paper obtains the characteristics of signal spectrum distribution, that is, the azimuth spectrum of stationary target signals has narrow band characteristics, while the azimuth spectrum of side-lobe interference signals is wide band. Then on this basis, an interference suppression method in azimuth frequency domain is proposed. Firstly, the window function weighting method is used in the range direction. Then, the data of azimuth direction is transformed to the frequency domain by Fourier transform. The filtering process is completed by the narrow band-pass filter which is calibrated and constructed in advance, and transformed back to the time domain finally. Compared with others, the proposed method can get better interference suppression effect under strong scattering environment and improve the signal to clutter ratio of weak targets. The validity and effectiveness of the proposed method are verified by the experimental data of 93 GHz FOD radar.