Design and simulation of pattern reconfigurable antenna based on RF-MEMS

Abstract：The reconfigurable antenna based on RF-MEMS is hot researching direction in recent years,it can change electric parameters,such as radiation pattern,working band, input impedance, polarization diversity,and so on. reconfigurable antenna of multi-band and multi-mode can replace multiple antennas based on one vehicle,decreases the developing price,size and weight of antennas,which is very important to the satellite communication and wireless communication. This paper presents the design of a broadband and wide-angle pattern reconfigurable antenna. The antenna is composed of four different linear phased arrays, in which the element is designed with different phase shift. The pattern of the whole antenna can be changed by six RF-MEMS switches, which are placed in the feed network. The feed network uses a novel compact broadband impedance transformer, and the microstrip slot antenna acts as an antenna element. The VSWR(Voltage Standing-Wave Ratio) of the antenna element in a broadband from 2.4 GHz to 3.4 GHz is less than 2. The simulation result demonstrates that the reconfigurable antenna realizes different patterns(0°,25°,40°and 50°) in different RF-MEMS switching states, furthermore, theVSWR of the reconfigurable antenna under each of these four different states is less than 2 from 2.5 GHz to 3.25 GHz except for part frequency points.The paper has important value to the design of beam scanning of phased array antenna in satellite communication. Key words：RF-MEMS switch,reconfigurable antenna,microstrip slot antenna,broadband impedance transformation. I