Characteristic basis function analysis of large aperture-fed antenna arrays

The Characteristic Basis Function Method (CBFM) is applied to rapidly compute the impedance and radiation characteristics of electrically large aperture-fed antenna arrays. A stationary formula for the antenna input admittance matrix is expressed in terms of a product of matrix blocks that are readily available from a method of moment formulation. Numerical results are shown for large arrays of waveguide antennas requiring more than 2 million basis functions, which is reduced by a factor of 9000, so that the solution for the currents are still obtainable in-core on a single desktop computer, while being orders faster than commercial software codes or a standard MoM approach, provided that sufficient memory is available for the Gaussian elimination.