Design Of Horizontal Polarization And Research On Optimization For Waveguide Slot Antenna

With the thriving of global aviation industry,the quantity of aircraft and service vehicle is increasing rapidly.It will be a tough task for us,in the future,to regulate these transports in such sophisticated circumstance in order.Besides,things will be more complicated in case of human,climate and terrain factors—especially view interruption in low-visibility weather or even by obstruction,tall building,for instance.Usage of Surface Monitor Radar(SMR)makes it possible to solve this problem and it is necessity to work it out.Waveguide slot antenna,As the most important hardware part in SMR,is widely applied nowadays.Waveguide slot antenna is a device that help to produce electromagnetic radiation by carving a series of apertures on the wall of waveguide with given angle and depth,in which the radiating aperture and feeding structure are intimately contiguous physically.therefor it has such advantages as simple structure,convenient installation and good strength.In terms of performance indicators,the waveguide slot antenna has the dual characteristics of the transmission line and the radiation antenna,so it has the advantages of high radiation efficiency,narrow lobes and low side lobes.However,the individual waveguide gaps can't achieve all the characteristics required by SMR: low side lobes,narrow lobes,vertical cosecant squared shape,circularly polarized radiation,etc.These metrics can often be achieved by a good match with other functional modules.Therefore,the main work of this thesis includes the research on the polarization characteristics of the waveguide slot antenna,and the corresponding exploration is showed based on the actual engineering project.1.Research on a simple waveguide slot antenna: Based on the simplest waveguide slot structure,the depth and inclination of the slot depth are analyzed given a rectangular waveguide,and the variation law is summarized by HFSS simulation software and physical test.2.The polarization performance of the polarized filter is designed.Based on the existing waveguide slot antenna,a suitable polarization filter is designed and assembled to reduce the vertical polarization component as cross polarization.According to the general design,the admittance of the filter matching is set by the transmission line theory,so that the waveguide slot antenna and the polarization filter are well matched,and the design of the two lacks a suitable model and a simple formula,and strives to form during the research process.Effective design process.3.Optimization of Polarization Purity: After completing the computer simulation,combined with the physical test to optimize the polarization purity,based on the above research,further refine the existing results,combined with the achievability analysis and improvement of the project.