Research On High Performance Combined Horn Antenna And Its Miniaturization Technology

This paper researches and designs the high-performance,multi-band and miniaturization technology of the horn antennas.The focus is on ensuring the high-performance of the antenna while making the structure of the antenna simple and compact.The main work includes the following three aspects:1.The design principles and methods of corrugated horn and multi-mode horn antenna are studied.Starting from the analysis of the aperture field,the key technologies of beam equalization and high polarization isolation of the horn antenna are analyzed.Based on the corrugated segmented structure,a C-band corrugated horn antenna with a bandwidth of4.44%is designed.and a method of controlling the corrugation mode is proposed,which improves the stability of the antenna gain in the frequency band,and achieves a gain of23.25±0.2d Bi.The beam equalization characteristic is good,and the polarization isolation of the antenna reaches 45d B.Combined with the design of OMT,the port isolation above45d B is guaranteed.The actual measurement and simulation results are consistent.2.The key technologies of multi-band,common-aperture and combined multi-mode excitation are studied?In view of the difficulty of taking into account the high performance of each frequency band in the design of multi-frequency common-aperture horns,a scheme of applying a dual-frequency corrugated excitation structure with frequency response to the antenna is proposed,which effectively improves the antenna beam equalization characteristic and in-band gain fluctuation.In addition,when the antenna layout is relatively compact,how to ensure high transmission and reception isolation between the two antennas is also a key issue that needs to be solved.The influence of different decoupling measures on the isolation of antenna transceivers was compared,and four methods are used to combine to reduce the coupling between the two antennas,and achieve a transceiver isolation of more than 80d B.An LSC three-band common-aperture combined horn antenna was designed and tested.The antenna beam equalization is good,the in-band gain is stable,and the antenna polarization isolation in the three frequency bands is better than 38d B.The actual measurement and simulation results are consistent.3.The miniaturization technology of high-performance corrugated horn antennas is studied.and the current low-frequency high-performance horn antennas are large in size,and the miniaturization problems are solved.Taking the L-band dual-polarization horn antenna as an example,the research and design are carried out.A wide flare angle corrugated design is adopted in horn section,which reduces the length of the antenna while controlling the influence of the aperture phase deviation,ensuring the high performance of the antenna.The waveguide section innovatively proposes a differential feed conformal design scheme.The waveguide section replaces the OMT with a differential feed.The symmetrical structure of the differential feed suppresses the excitation of the even mode.In addition,the influence of the length of the waveguide on the mode of the waveguide port is studied to achieve a balance between reducing the length of the waveguide section and suppressing high-order modes,and further ensuring high performance while miniaturizing.The conformal design of the differential network reduces the radial size of the antenna and improves the degree of antenna integration.When the length of the antenna is 2.39?₀,the simulation realizes that the polarization isolation is better than 56d B Within±3°of the maximum directionin,and the gain in the 12%bandwidth is greater than 13.5d Bi.