Quad-beam Bidirectional Single Metal Layer Array Antenna Optimized with Genetic Algorithm

A bi-direction muti-beam single layer metal-only array antenna is presented in this paper, which shows a good quad-beam performance on both reflection and transmission plane. The adopted square slot-type elements whose reflected and transmitted cross-polarized fields can provide the same and full 360° phase range make contribution to realize the bidirection. Optimization method based on Genetic algorithm (GA) is implemented to generate muti-beam radiation pattern by optimizing the phase distribution on the array antenna. To validate the proposed design, a 39GHz quad-beam reflect transmit array (TRA) antenna composed of a thin metallic sheet with 400 elements, spatially fed by a corrugated horn is designed and simulated. The simulation results show that quad-beam TRA has side-lobe below -13.1 dB, and directivity of 13.2 dBi in average over the operating frequency for each desire direction.