The Extension Research Of The Coupling Cavity Filter Based On Substrate Integrated Technology

At present, with the rapid development of wireless communication, variety of ways of transmission. So the system request: highly integrated, small size and low cost.The substrate integrated waveguide(SIW) is widely used in microwave/millimeter waves because of the advantages of high quality factor and high power capacity as the traditional metal rectangular waveguide; and the advantages of high planar-integration and relatively small volume as the micro-strip structure. The integrated filter is integrated with the substrate integrated waveguide technology, so as to realize the integration and miniaturization of the filter. The cross coupling technique can improve the filter’s performance by introducing the limited transmission zero to improve the band rejection.In this paper we focuses on the design of the coupling cavity filter based on substrate integrated waveguide.1. Learn the basic theory of microwave filter, and the performance index of the filter are briefly introduced, finally the method of design the filter is given.2. Based on the study of the transmission characteristics of the substrate integrated waveguide, The two cavity, four cavity filter is designed on the single layer and the simulation results are given.3. The technology of cross coupling is studied. Based on this, the cross coupling cavity filter is designed, which is based on the substrate integrated waveguide technology. The transmission zeros are introduced, and the performance of the filter is improved.4. The coupling cavity filter based on substrate integrated waveguide both on the single layer and double layers. The transmission zeros are introduced to improve the band rejection capability of the filter.5. Design an oversized SIW cavities filters at 15 GHz, select the appropriate feed port to make the filter on the upper and lower resistance with each generation of a transmission zeros, the effective improvement of the filter frequency selection and stop band rejection.6. Design a bandpass filter based on high order mode SIW resonator, which makes the device filter more easy to process in high frequency. At the same time, the high order mode filter based on the hexagonal resonator is designed, which uses a double layer structure, and the transmission zero is generated by cross coupling. Design a filter fed by the substrate integrated coaxial line, and the upper layer and the lower layer are respectively composed of two cavities, which form two transmission paths to produce transmission zeros, and improve the selectivity of the filter.