ADS-B抗干扰阵列天线幅相误差的无源校正

Passive calibration of gain and phase errors for ADS-B anti-jamming antenna array

阵列的幅相误差会使真实阵列流形与理想阵列流形有较大偏差,导致阵列性能急剧恶化,甚至失效。根据广播式自动相关监视(ADS-B,automatic dependent surveillance-broadcast)系统的特性,提出一种校正幅相误差的无源校正算法。利用ADS-B系统中飞机广播的ADS-B信号作为校正源,通过其中一个阵元接收的数据求得飞机位置,再加上所测阵列天线位置,通过坐标系转换可求得校正源的来向信息,并利用该信息进行误差校正,可以较准确地估计出阵列的幅相误差,校正后阵列的性能有明显改善。该方法无需额外设置校正源,与其他方法相比,减少了校正阵列时设备的复杂度。仿真结果表明算法的有效性。

The real array manifold and ideal array manifold may be different due to the gain and phase errors of array, and performance of algorithms will be sharply affected by the gain and phase errors. A passive calibration algorithm is proposed to calibrate the gain and phase error of the ADS-B system array. In the proposed method, one of the sensors can be used to obtain the positions of aircrafts, and the position of array antenna can be measured, then the DOA of pilot source is computed through coordinate system transformation, and the array errors are calibrated by using direction information. Gain and phase errors can be accurately estimated by the proposed method, and the performance of algorithms is effetively improved. Performance of calibrated array is highly improved. The extra pilot sources do not need to be set manually, thus the equipment complexity is reduced. Simulation results prove the effectiveness of the proposed algorithm.