Array Decomposition Method for Arbitrary-Element Regular Arrays Using Higher Order Basis Functions

The full-wave array decomposition method for regular antenna arrays with arbitrary elements using higher order hierarchical basis functions is investigated. We show that the use of higher order basis functions results in significantly reduced memory consumption and computation time for a
$\mathbf {10\!\times\!10}$
element conical horn array with an aperture size of
$22\!\times\!22\lambda$
, without the need for analytical nor numerical approximations. In addition, we demonstrate that by employing higher order basis functions, the far-field error is considerably lower than by using common first-order basis functions for the same total number of unknowns.