基于柱面共形阵列天线的快速波达方向估计

Fast DOA estimation based on cylindrical conformal array antenna

由于共形天线载体曲率不同,阵列中每个阵元的方向图的指向各不相同,这导致了阵列中各个阵元极化特性(polarization diversity,PD)的差异。因此,共形阵列天线的数学模型中考虑了不同阵元的极化特性。共形阵列实现波达方向(direction of arrival,DOA)估计的过程中,主要难点在于信源方位参数与极化状态的去"耦合"。本文利用圆柱的单曲率特性,通过合理摆放子阵中的天线阵元,结合传播算子方法(propagator method,PM)和子阵分割技术,提出了一种适合于柱面共形阵列的DOA估计方法。本文的DOA估计算法不需要天线单元方向图的任何信息,不需要谱峰搜索和参数配对,计算量较小。最后通过Monte-Carlo仿真实验验证了本文算法的有效性。

The pattern of each element in the conformal array has a different direction because of the curvature of the conformal carrier, which results in the polarization diversity （PD） of each element. The polarization parameters of incident signals are considered in snapshot data model. The coupling between polarization status and parameters of source is the distinct difficulty in direction of arrival （DOA） estimation of conformal array antenna. A blind DOA estimation algorithm is proposed based on propagator method （PM） and sub-array divided technique for cylindrical conformal array antenna, in which special sub-arrays are designed. The decoupling method for DOA and polarization parameters is implemented, and a high-resolution DOA estimation algorithm is proposed. The proposed algorithm achieves the 2D-DOA estimation without the element pattern. Without spectral peaking searching and complex computation, this algorithm works well for pairing among parameters. Furthermore, the validity of this algorithm is confirmed by Monte Carlo computer simulations.