A simple method for null steering in a circular array by perturbations of the radial locations of the elements

A reliable communication link between two destinations in a microwave environment requires a propagation path clear of interference signals. An effective method of interference suppression is to form nulls in the antenna pattern in the directions of the interference. Steyskal (1983) proposed null steering in the antenna pattern by using the small phase perturbation. This paper extends the spatial phase perturbation methods used for null steering in a linear array to include a circular array. In this technique the array utilizes the phases obtained from perturbing the radial locations of a circular array to suppress the interference signals. This technique is applied to a Chebyshev-like circular array with 36 elements.