Adaptive nulling with spherical arrays using a genetic algorithm

Spherical arrays are arrays that conform to the surface of a sphere. One approach to a spherical array layout is to mold a planar array to the surface of a sphere (spherical-planar array). Another approach is to create circular arrays about the spherical surface (spherical-circular array). This paper presents an approach to adaptive nulling with either type of spherical array using a genetic algorithm. Amplitude and phase adaptive nulling with a genetic algorithm generates deeper and faster nulls than phase-only nulling. A genetic algorithm is used to place a null at the sidelobe of two types of spherical arrays. The 16/spl times/6 element, 256 elements, rectangular grid half wavelength spaced spherical planar array, and the spherical-circular array with same number of elements as the spherical-planar array are simulated and compared.