Research on Genetic Algorithm of Antenna Arrays Beam Shaping with Side Lobe Suppression

Abstract

Excitation optimization algorithm based on Genetic Algorithm (GA) is mainly used to solve the excitation problems of array antenna beam shaping. When optimizing the excitation of array antenna by traditional genetic algorithm, the beam of array antenna is synthesized by radiation shape of elements in antenna array, and then the results will be compared with the target pattern. After several operations, the excitation will meet the deign requirements. However, in traditional genetic algorithm, neglected suppression of side lobe leads to an unsatisfactory high level side lobe. In this paper, a new method of beam synthesizing by peak beam of array antenna is proposed. By comparing the shape of synthesized beam with target beam and combining with traditional GA, the synthesized beam matching the target beam with low side lobe will be obtained. Taking a 16 elements X band micro-trip dipole linear array antenna as an example, the results of simulation show that array antenna has high level side lobe suppression at about -27.5 dBc using the method proposed in this paper, which is much better than -19 dBc side lobe suppression using traditional GA.