In this study, a method for amplitude and phase constrained focal plane array pattern synthesis based on the intersection approach and Gram-Schmidt orthogonalization is presented. A new formulation for alternation projection, which leads to a efficient and simple algorithm, is given. The basic idea of the method is to utilize Gram-Schmidt orthogonalization as the projection operator in the iteration step of the alternating projection method. A number of examples are presented to highlight various aspects of the proposed method.