Finite periodic structure approach to large scanning array problems

A new formulation called the finite periodic structure method is proposed which is useful for treating mutual coupling problems in large antenna arrays. The discrete array problem is first converted into a series of continuous aperture problems using Poisson's sum formula. Spatial Fourier transforms are then used to represent the impedance in a form similar to the infinite periodic structure approach. The active impedance is then given by a convolution integral involving the infinite periodic structure solution and the Fourier transform of the equivalent aperture distribution of the current over the entire area of the array. The formulation is particularly useful for large finite arrays and edge effects; current tapers and nonuniform spacings can also be included in the general formulation. The forced excitation problem is discussed to illustrate the method.