Scattering Analysis Of Large-Scale Antenna Array Using A Hybrid CBFM-FE-BI Technique

Scattering analysis of large-scale antenna array is an important topic, which has both urgent needs and technical difficulty. Efficient numerical algorithm, which is able to handle scattering problems of Large-Scale complex antenna array, is deeply studied in this paper. The main contents and research works in this paper include the following aspects:(1) Considering that these antenna array elements usually have a variety of materials and complex structures, we firstly study the algorithm which can analyze the electromagnetic properties of complex objects. FE-BI method combines the method of moments (MoM) and the finite element method (FEM) and can be used to analyze the scattering of objects which may be metallic, dielectric and composed objects.(2) For calculating the radar cross section (RCS) of the antenna array, we study two types of characteristic basis function method (CBFM) which are efficient to analyze the array structures. The singular value decomposition (SVD) and adaptive cross approximation (ACA) method are also presented to improve the CBFM.(3) We propose an efficient hybrid CBFM-FE-BI approach to analyze the antenna array which has large scale and multiple excitations. By utilizing the hybrid method, the whole array structures are divided into several blocks, and a set of the new characteristic basis functions independent of the incidence are generated. Furthermore, the singular value decomposition leads to a significant reduced matrix so that LU decomposition can be directly used to solve the matrix and avoid the convergence problem in iterative methods.(4) ACA is studied so that the matrix filling of the coupling impedance between block units is accelerated. Finally, the hybrid ACA-CBFM-FE-BI method is obtained to improve the computational efficiency. Numerical results are provided to demonstrate the efficiency and accuracy of the method compared with the results of commercial software FEKO.