Radiation Beam Pattern Synthesis of Concentric Circular Antenna Arrays Using Hybrid Approach Based on Cuckoo Search

A novel hybrid approach to suppress the maximum sidelobe level (SLL) of large scale concentric circular antenna array (CCAA) is proposed. The approach includes an improved discrete cuckoo search algorithm (IDCSA) for thinning the CCAA and a cuckoo search-invasive weed algorithm (CSIWA) for further optimizing the thinned CCAA. IDCSA introduces the nest location coding discretization, the mapping method based on jumping path, and an improved egg elimination mechanism for optimizing the discrete sparse array synthesis problem. Moreover, CSIWA introduces the chaotic initialization and the invasive weed-based Lévy flight method to solve the continuous excitation current optimization problem. Simulation results show that the thinning rate of CCAA obtained by IDCSA can reach more than 50%, resulting in significant cost savings. Moreover, both IDCSA and CSIWA can obtain a lower maximum SLL compared with other algorithms while achieving faster convergence rates. The stabilities of the proposed IDCSA and CSIWA are demonstrated by using multiple independent tests. In addition, the performance of the optimized designs obtained by the hybrid approach is also verified by electromagnetic simulations.