Research On Low Profile Wideband Ku Band Phased Array Antenna

Phased array antenna with high gain,beam shaping and beam scanning have become the main means of transmitting and receiving signals for modern information systems,which have been widely used in wireless communication,radar and navigation fields.To meet the development demand of modern information system for higher speed,wider coverage and more functions,the array antenna needs to take the wide bandwidth,wide beam scanning capability,low profile and planarization into account.To cope with the above requirements and challenges,this thesis takes the phased array antenna of Ku-band,low-profile and wideband as the research direction.It studies the wideband of microstrip antenna and the wide-angle scanning of phased array antenna,which bases on the wideband method of microstrip antenna,the L-type probe coupling feed technology and the loading equivalent cavity structure.The specific content includes the following aspects.1.With the aids of equivalent circuit analysis and electromagnetic simulation,the thesis studies the wideband technology of microstrip antenna.2.This thesis designs 8×8 array antenna composed of microstrip double-layer patch antenna basing on L-type probe coupling feed.The simulation results indicates that the array antenna works from 13.5 GHz to 18 GHz(the relative bandwidth is 28.6%)with active VSWR<2.The array antenna can achieve ±45°and ±60°scanning coverage on the E and H planes.And its radiation characteristics perform well.3.The thesis designs 8×8 array antenna of microstrip double-layer patch structure fed by L-type probe coupling of loading equivalent cavity structure.The simulation results indicates that the array antenna operates from 13.5 GHz to 18.75 GHz(the relative bandwidth is 32.5%)with Active VSWR<2.5.The array antenna can achieve ±60scanning coverage on both the E and H planes.The measurement and simulation of the array antenna indicates that array antenna operates from 13.0 GHz to 18.0 GHz(the relative bandwidth is 32.3%)with active VSWR<3.The array antenna can achieve ±60 scanning coverage on both the E and H planes.The test results are basically consistent with the simulation results.4.To make it better applied to the field of millimeter-wave radar antennas,Chebyshev low-sidelobe synthesis is carried out on the microstrip double-layer patch array antenna with L-type probe coupling feed and loading with equivalent cavity structure.The simulation results indicates that the level difference between the main and sidelobe is 26 d B after the 26 d B low sidelobe weighting of the array antenna,and the scanning coverage of ±60° can be achieved on both E and H planes,and the scanning gain drop of the array antenna is further reduced.