A hybrid topology optimization method based on sensitivity analysis

We propose a hybrid topology optimization method, which combines the material distribution method and the level set method. It can be used for the optimization of microwave circuits and antennas. This method takes advantages of the topology searching ability of the material distribution method and the smooth boundary feature of the level set method. We derive the sensitivity analysis formula for the far field intensity of the antenna and apply it in the radiation pattern optimization problem. Three microstrip directional antennas are optimized for maximum gains in the elevation angle of 0, 30, 60 degrees respectively. The performance of the optimized antennas is verified by commercial software HFSS. Simulation results show that all antennas have maximum gain beyond 10dBi and S11 below -15dB at prescribed frequency 5GHz.