On Array Failure Mitigation With Respect to Probability of Failure, Using Constant Excitation Coefficients and a Genetic Algorithm

Switched-beam antenna arrays (SBAs) are widely used in communications systems in order to increase system capacity and spectral efficiency. If an element fails during operation, a significant degradation of the array's performance is observed, even after redistribution of the array's excitation coefficients. Furthermore, redistribution of the excitation coefficients is not always possible. In this letter, a study on the effect of an element failure to an array's radiation patterns, with respect to the probability of failure, is performed. It is shown that mitigation of failure effects is possible if the possibility of failure is taken into account during early design stages. This is accomplished by using a modified genetic algorithm (GA). With the proposed methodology, mitigation is achieved even without the need to redistribute the array's excitation coefficients.