存在通道幅相与互耦两种误差的均匀圆环阵流形曲线拟合方法

针对实际装配后均匀圆环阵的阵列流形向量偏离理论值的问题,提出一种利用单声源从不同方位入射阵列时的阵列幅度相位响应拟合阵列流形模型的算法。考虑阵列存在通道幅度相位一致性偏差和阵元间互耦作用,导出阵列幅度相位响应与流形误差参数的关系式,利用互耦矩阵在模态域可与阵列流形分离的特性,将关于误差参数的关系式降次为线性方程组,再联合多个方位对误差参数做最小二乘估计。对于只存在其中一种误差的特例情况,给出了对应高精度、低复杂度的估计方法。最后,利用数值仿真对所提方法的拟合精度进行评估,拟合后的阵列流形误差距离缩减至10-2量级,水池实验数据也验证了算法在实际应用中的可行性。 

Manifold curve fitting in the presence of channel gain phase inconsistency and mutual coupling for uniform circular array

The manifold vector of an assembled Uniform Circular Array(UCA) usually differs from its theoretical value,and a calibration algorithm for the array manifold model is proposed on the basis of array amplitude phase response when a single signal source is incident into the UCA from different directions.Firstly,considering the existence of channel gain phase inconsistency and mutual coupling,the relationship between the amplitude phase response and the array manifold error parameters is derived.Then utilizing the feature that the mutual coupling matrix can be separated from the array manifold in the modal domain,the relational expressions about error parameters is reduced to a linear equation.Finally,the least squares estimation of the error parameters is made by combining multiple data from different directions.For the special case where there is only one kind of error,an estimation method corresponding to high accuracy and low complexity is given.Finally,the numerical method is used to evaluate the fitting accuracy of the proposed method,and the estimated array manifold error distance is reduced to the order of 10-2.The experimental data of the pool also verify the feasibility of the algorithm in practical applications.