Design of a lens antenna with wideband and high gain characteristics based on genetic algorithm

In this research, a multi-objective genetic algorithm is proposed for the optimization of lens antenna. Different from the traditional optimization methods, which optimize the focus of the lens by using a formula or scanning parameters, this method directly takes the gain and 1-dB steady gain band of the lens antenna as the optimization objective. The topological structure of the lens is optimized by the algorithm. To verify the effectiveness of the proposed method, a broadband, high-gain, all-dielectric lens antenna is designed, and the lens is fabricated by 3D printing technology, which can reduce the cost. The measurement results show that the lens effectively increases the gain of the source by 6.4−10 dB in 6−18 GHz, and the proposed antenna has a 23.8 dBi maximum gain at 18 GHz. In addition, the proposed design achieves a 40% 1-dB gain bandwidth and 51.9% peak aperture efficiency. The effectiveness of the design method is verified. This research also provides a fast and convenient method for optimal design of lens antenna.