Research On The Technology Of Moving Wide Angle Scanning Array Antenna

Compared with the mechanical antenna,the phased array antenna used for SOTM(Satellite communication On-the-Move)has the advantages of fast searching speed,low profile,light weight and other advantages.It is suitable for all kinds of high-speed moving platform.The phased array antenna is the trend of SOTM.Two-dimensional phased array are realized by the electric sweep in the pitch plane and the azimuth plane,the array needs a large angle stable gain coverage to meet the communication needs of SOTM system.Therefore,the study of two-dimensional wide-angle scanning antenna has important significance.A series of studies on S-band wide-angle circularly polarized two-dimensional phased array antennas are carried out in this paper.After extensive research,Wide-beam circularly polarized antenna elements are chosen to realize wide-angle scanning arrays.Firstly.An S-band 3D ground+ dielectric microstrip antenna was designed.The wide-beam characteristic of the antenna element is realized by the electromagnetic wave reflection by 3D ground and the enhancement of the surface wave by the thick dielectric.The simulation result shows that the 3dB beam-width of the antenna is greater than 120°,and the circular polarization property is good in a wide beam range.The results of the research have a certain reference significance for antenna design with wide beam demand,such as navigation antenna.In order to further reduce the profile of the element antenna,a novel "saddle-shaped" wide-beam microstrip antenna with cavity structure was designed.The paper discussed the principle of forming "saddle" radiation pattern and analyzed the key parameters.The antenna was fabricated and tested.The test result shows that the antenna has "saddle" radiation pattern,wide beam-width(3 dB-beamwildth is greater than 140°)and circular polarization features.The research results have significance for wide-angle scanning phased array antenna design.Finally,a wide-angle scanning circularly polarized array antenna was designed with the practical project as support.The key issues of array form selection,array spacing were discussed.The array element layout is optimized by the scanning gain maximization.The result shows that the antenna scanning angle covers 360°±65°(azimuth plane,Pitch plane),the scanning gain flatness is less than 2.5dB.Based on this,the antenna array was fabricated and tested.