Research On Wide-band Wide-angle Dual Circular Polarized Phased Array Antenna

Phased array antennas are widely used in radar,electronic warfare and information communication fields.Wide-bandwidth and wide-angle scanning phased array can achieve high-rate information transmission and wide-range beam coverage,which can effectively increase system capacity,reduce system volume and reduce system cost.In recent years,related fields have become the research hotspot of phased array antennas.Based on this background,a series of explorations are made on the bandwidth broadening and scanning Angle elevation of two-dimensional dual-circular polarized phased array antenna,and designs the related arrays base on the microstrip antenna and the tightly coupled array.The dissertation is arranged as follows:The first chapter introduces the research status of related fields which is divided into one-dimensional array and two-dimensional array.At the same time,the implementation of dual-circular polarization is introduced.The second chapter briefly introduces the basic theory of phased array antenna design which includes the analysis method of array scan beam and the introduction of active VSWR and active element pattern.In chapter three,according to the design idea of traditional array antenna,the wideband wide-angle dual-circular polarization array is realized by designing the wideband microstrip element and array the element.The research content of this chapter can be divided into three parts.The first part broadens the bandwidth of the microstrip antenna through the four-port L probe.In the second part,a broadband miniaturized feeding network is designed by using open-circuit shunt stubs.In the third part,the rectangular grid array is arranged and the performance of the array is analyzed.Finally,the array can be scanned with dual-circular polarization and wide angle range at 40% relative bandwidth.In the fourth chapter,the design of wideband dual-circular polarization array is accomplished through the design idea of tightly coupled array.The research content of this chapter can also be divided into three parts: the first part analyzes the reasons of the deterioration of the axial ratio under the large angle scanning and designs the compact coupling unit with the same phase center and the balun which satisfies the isolation degree requirement under this structure;In the second part,a feeding network is designed by using unbalanced strip-line according to the unit requirements.The third part solved the related problems in processing by using coaxial connectors which have fuzz buttons and multi-layer PCB technology.Finally,a 64 ports wave control network is used to test the array as a whole,and the measured results show that the array can achieve dual-circular polarization scanning in a bandwidth of 40% and the measured results agree well with the simulation results.Chapter five summarizes and anticipates the thesis.The highlight of this paper is to analyze and solve the problem of the deterioration of the axial ratio of circular polarization in the case of large angle scanning.The bandwidth and scanning angle of double circular polarization array can be further expanded by using wide angle matching layer and more reasonable structure.