Optimum ring spacing and interelement distance for sidelobe reduction of a uniform concentric ring array antenna using differential evolution algorithm

Reduction of sidelobe level in a concentric ring array results in wide first null beamwidth. The authors propose a pattern synthesis method based on the Differential Evolution (DE) algorithm to reduce the sidelobe level of a concentric ring array of isotropic antennas while keeping the first null beamwidth (FNBW) fixed and variable by optimizing both ring spacing and interelement distance of each ring.