A subdomain multilevel approach for the efficient MoM analysis of large planar antennas

A novel method, accelerating the method-of-moment (MoM) analysis of large, complex-shaped microstrip antennas, is presented. The basic step in the approach is to divide the complex geometry into simpler subdomains, which immediately means to split the entire large computation into several smaller subproblems. The crux is then to combine the partial solutions to a compressed global moment system, taking into account the symmetries and mutual coupling. The numerical results of the proposed method are compared both to brute-force computations and measurement data. They show excellent agreement, giving, for instance, for the input impedance of a four-patch antenna, an error of less than 0.3%, while the matrix is reduced by a factor of 2.7, requiring only 14% of the initial memory size.