现有基于电磁矢量传感器阵列的信号DOA和极化参数联合估计算法,大都假设电磁矢量传感器的三个电偶极子和三个磁偶极子严格指向参考坐标系的三个坐标轴,即不存在原位误差.然而在实际应用场合,电磁矢量传感器是存在原位误差的,因此其实际极化-角度域导向矢量与理想情况下的极化-角度域导向矢量有一定的偏差,导致现有方法的估计性能显著下降,因此必须对原位误差进行校正.通过对存在偏差的极化-角度域导向矢量进行一阶Taylor近似展开,并利用一个辅助校正源,提出了电磁矢量传感器原位误差校正方法,给出了原位误差估计的CRB界.仿真结果验证了该方法的有效性.
Most existing direction-of-arrival(DOA)and polarization estimation methods,which based on electromagnetic vector sensors array,generally assume that the electromagnetic vector sensor orient the referenced Cartesian coordinates strictly,i.e.,no orientation errors exist.While in the practice,the orientation errors are unavoidable,which make the manifold of the vector sensor deviate from the ideal value,and deteriorate the estimation performance of the existing methods.So it is necessary to calibrate the orientation errors of the electromagnetic vector sensors.Based on the first-order Taylor approximation of the manifold and a known source,a new calibration algorithm against the orientation errors of electromagnetic vector sensors is proposed,and the corresponding expressions for the stochastic Cramér-Rao bound(CRB)is derived.The performance of the new method is confirmed through numerical examples.