Research On Coupling Circuit Based On Corrugated Substrate Integrated Waveguide

Substrate Integrated Waveguide(SIW)has attracted wide attention due to its outstanding advantages of low loss,high Q value,low cost and easy integration.However,there are two rows of metal holes in the SIW,which makes the process more complicated.Corrugated Substrate Integrated Waveguide(CSIW)as a novel technology solves the pain points of SIW.It uses a quarter-wavelength comb line instead of metal holes,which not only simplifies the processing technology,but also facilitates integration with active circuits.This paper is based on CSIW to carry out the research on CSIW power divider and filter.First,the paper designed a double-layer 3d B power divider based on HMCSIW(Half-mode Corrugated Substrate Integrated Waveguide).The upper and lower layers are coupled to achieve power equalization,which has a wide operating frequency range.The feed port uses trapezoidal microstrip transition,and the two output ports are spliced by a trapezoidal microstrip and a quarter circular arc microstrip,which realizes the separation of the two output ports.Next,a novel wideband bandpass Corrugated Substrate Integrated Waveguide filter combining Electromagnetic Band-Gap(EBG)Structure and Defected Ground Structure(DGS)are proposed.The insertion loss in the passband is less than 0.5d B,the return loss is less than 15 d B.Compared with the traditional CSIW filter,the filter based on this new method has better out-of-band suppression performance.In order to further reduce the size of the components,HMCSIW is obtained by cutting the CSIW along the central axis.By loading a quarter-wavelength short-circuit stub on the broad-wall of HMCSIW,the transmission performance of HMCSIW is improved.Finally,an ultra wideband filter with a quarter wavelength short-circuit stub line is designed.Considering the spectrum utilization,first,a wide-band parent filter is designed,and then two L-shaped branch lines are introduced to couple the source and load to generate transmission zeros,which is an innovation of HMCSIW applied in dual passband filter.