Analysis of scattering arrays using the principle of stationary phase

The stationary phase approximation technique is developed for scattering arrays and is used to analyze the scattering from large arrays on planar or non-planar surfaces. The analysis retains the effect of element spacing on the scattering pattern and can be applied to configurations with non-uniform element spacing and non-linear element phase delay. Analysis of a ring array, a spherical cap array and linear array with non-uniform element phase delay are given. Computer solutions are presented for the ring array to demonstrate the approximation accuracy.