Research On Multi-Band Microwave Passive Components Based On Structural Recombination

Structural composite ridge waveguide is a new type of structural composite transmission line composed of substrate integrated waveguide and substrate integrated ridge waveguide.Different from the various passive devices required for the separate design of a variety of transmission lines in traditional microwave systems,the structural composite ridge waveguide can easily realize the multi-functional integrated design of multi-frequency circuits and antennas,which greatly reduces the volume of the whole system.It has great application value in the development of multi-frequency microwave passive circuits such as filters,duplexers,and antennas.This thesis focuses on the characteristics and design methods of various passive devices of structural composite ridge waveguides.The main research contents are divided into the following parts:Firstly,the structure and transmission characteristics of the structural composite ridge waveguide are studied,and three microstrip transition structures are designed.On this basis,for the multi-frequency passive circuit,a structural composite ridge waveguide dual-band filter is designed,which realizes the coupling topology of six resonators in the upper and lower layers.The operating frequency band is located in the X-band.The detailed tolerance simulation analysis of its parameters is carried out,and the machining test is consistent with the simulation results.At the same time,a compact high-isolation diplexer operating at 20/28 GHz is designed.Both passbands are designed with fifth-order Chebyshev filters,and the isolation in the passband is higher than 50 d B after measurement.Finally,for the multi-frequency passive antenna,a structural composite ridge waveguide 5G millimeter-wave dual-frequency multi-beam slot array antenna is designed,which works in the 28/38 GHz frequency band.The high-frequency part is a 2×2 SIW slot antenna array,which can receive incoming wave signals from the elevation plane for direction finding.The low-frequency part of the antenna array introduces a Butler matrix feed network,which can realize multi-beam scanning.