A Low Sidelobe Microstrip Antenna Array for 24 GHz UAV Obstacle Avoidance Radar System

A low sidelobe microstrip antenna array for 24 GHz UAV (Unmanned Aerial Vehicle) obstacle avoidance radar system is designed according to the characteristics of direct flight UAV. In this paper, the theoretical model of the antenna is described, and the microstrip antenna unit and feeding network are designed by the electromagnetic simulation software and numerical calculation software. The simulation results show that the center frequency of the antenna array is 24.5 GHz, the gain is 25.05 dB, the beam width is 8.46°, and the sidelobe suppression is -16.62 dB. Impedance bandwidth and radiation bandwidth are greater than 1 GHz. The antenna was fabricated, and the actual measurement results show that the center frequency of the antenna array is 24.5 GHz, the beam width is 7°, the sidelobe suppression is -18.13 dB, and the radiation bandwidth is greater than 1 GHz. It is proved that the designed antenna has good bandwidth and direction characteristics, which can improve the detection range and detection accuracy of the UAV obstacle avoidance radar.