带内拟合宽带阵列通道误差校正方法

Channel mismatch calibration in broadband array

在整个第一Nyquist域进行宽带自适应阵列天线的幅相误差校正时,由于带宽宽,需要的横向滤波器阶数非常高。为了减少滤波器阶数,新方法仅仅对信号带宽内的幅相误差进行校正,采用最小二乘拟合的最优化准则,获得校正滤波器的实系数。同时,通过增加一个前置带通滤波器,保证带外噪声控制在可接受范围内。相对传统方法,该设计在相同滤波器阶数情况下,可以提高带内校正精度。通过对实际MSK信号下的阵列校正实验,证明了新方法的有效性。

The high order of the transversal filter for array error calibration is required when designing the filter in the whole first Nyquist region. The proposed methodology only considers the match in pass band of the signal, so that the order of the filter is much less. The least square fitting criteria is employed to compute the real coefficients of the calibration filter. In addition, a passband filter is utilized before the calibration unit to keep the noise acceptable. Compared with the traditional one, the new scheme improves the accuracy of the calibration filter in signal band with the same order of filter.The experiments in indoor chamber with MSK signal illustrate the effectiveness of new methodology.