Characteristic Basis Function Method Using Single High-Level Basis Function Per Subdomain For Efficient Analysis of Large Periodic Array Antennas

Recently, a novel characteristic basis function method (CBFM) formulation has been proposed for numerically efficient analysis of large truncated-periodic array antennas operating in the radiating mode. In this formulation, a single (and identical) high-level CBF is employed to represent the current distribution in each element of the antenna array. This CBF is constructed by solving the problem of a unit cell of the infinite doubly-periodic array. In this paper, a modified approach is proposed for generating the CBF associated with each edge or corner element in the presence of array truncation effects. The efficacy of both approaches is demonstrated by simulating the
$9\times 9$
array of bow-tie antenna elements. It is shown that good agreement with the reference solution from a commercial CEM solver is achieved, together with a significant reduction of the overall computational cost.