Design of non-uniform circular antenna arrays using biogeography-based optimisation

Biogeography-based optimisation (BBO) is employed for the optimisation of non-uniform circular antenna arrays. In BBO, the problem solutions are represented as islands and the sharing of features between solutions corresponds to immigration and emigration between the islands. The scheme of BBO is employed to find out an optimal set of weights and antenna element separations to provide a radiation pattern with maximum side lobe level (SLL) reduction with the constraint of a fixed major lobe beam width. The capability of BBO is demonstrated by taking different sizes of antennas. The results show that the design of non-uniform circular antenna arrays using the BBO algorithm offers a SLL reduction better than that obtained using genetic algorithms, particle swarm optimisation and simulated annealing.