Research And Design Of Muti-mode Satellite Terminal Antennas

With the continuous development of satellite communication technology,satellite communication systems have shown a development trend of different working modes compatible with each other.Ground satellite terminal antennas that can cover a variety of satellite operating frequency bands have become research hotspots in the field of satellite terminal antenna design.This article takes multi-mode satellite terminal antennas as the research objects,and designs four multi-mode satellite system terminal antennas according to the application requirements of different satellite working modes.The author's main research results can be summarized as:1.The dual-mode circularly polarized antenna was studied,and a dual-mode stacked single-feed circularly polarized microstrip antenna was designed.First,the realization method of the circularly polarized radiation of the microstrip antenna is analyzed,and the design indexes and difficulties of the dual-mode circularly polarized microstrip antenna are discussed;secondly,the chamfered patch with grooves is used as the radiation unit,and the stack is used.The layer structure realizes the dual-mode circular polarization characteristics,designs a singlefed dual-mode satellite terminal circular polarization antenna,and analyzes and discusses the influence of the antenna's various structural parameters on performance;finally,the processing and testing of the antenna are completed The test results show that the antenna can work in the L2(1.227GHz)band of GPS and the B1(1.561GHz)band of the Beidou satellite system.2.The multimode circularly polarized antenna was studied,and two multimode broadband circularly polarized antennas were designed.In the first antenna design,the feed network was used to provide a 90-degree phase difference for the radiating patch,and multi-mode broadband circularly polarized satellite antenna design was completed.Test results show that the antenna achieves an impedance bandwidth of 42.7%(1.05-1.648 GHz)and an axial ratio bandwidth of 48.6%(1-1.68 GHz).In the second antenna design,the directional coupler is used to design a one-four-feed network,thereby expanding the working bandwidth of the antenna.Test results show that the antenna has an impedance bandwidth of 83.6%(1.15-2.45 GHz)and an axial ratio bandwidth of 66.5%(1.17-2.2 GHz),covering L1,L2,L5 including GPS,L1,L2 bands of GLONASS and Beidou The B1,B2 and B3 frequency bands of the satellite system.3.The helical antenna is studied,and a planar spiral full-mode satellite terminal antenna is designed.A multi-mode helical high-gain broadband satellite terminal antenna capable of covering all satellite working modes is designed,and the structure of the antenna is optimized and analyzed to complete the processing and test work.The test results show that the antenna has an impedance and axial ratio bandwidth of more than 3GHz,which fully meets the coverage of multiple satellite operating frequency bands and maintains a stable radiation gain within the operating frequency band,with a maximum gain of 9.9d Bi.