Research On Theory And Application Of Integrated Substrate Gap Waveguide

With the development of microwave and millimeter wave circuit,the technology of waveguide,filter and antenna based on substrate integration have been received more and more attention of industrial and academic researchers,which promoted the communication systems to miniaturization,integration and multi-functional.To meet the requirements of future communication systems,Integrated Substrate Gap Waveguide(ISGW)technology is proposed based on substrate integration in recent years,which is self-packaged circuit,realized by technology of printed circuit board.For ISGW,the high radiation loss of traditional transmission line in millimeter wave or even sub-millimeter wave is reduced.The development of ISGW technology is in the start-up stage,with theoretical incompleteness and application of ISGW needing to be carried out urgently.The ISGW has great potential in feeding cavity filter,and the Electromagnetic Band Gap(EBG)structure in multilayer dielectric plate has great advantage in improving gain of antenna.In the dissertation,the theory and application of ISGW was studied,mainly including the following aspects.1.Study on the theory of integrated substrate gap waveguide.Combining the spectral Green’s function method and the transverse transmission line method,the theoretical calculation method of the effective permittivity of the integrated substrate gap waveguide was proposed,and the theoretical formulas of the effective permittivity and propagation constant of the integrated substrate gap waveguide were derived.2.Study on the application of integrated substrate gap waveguide.Firstly,the integrated substrate gap waveguide cavity filter was studied.An integrated substrate gap waveguide cavity dual-mode filter with double transmission zeros was proposed by means of coupling topological method of feed-position adjusted design.The ISGW dual-mode filter was realized by applied two feeding structures of microstrip ridge and coaxial line with two transmission zeros.Then the filtering antenna based on integrated substrate gap waveguide was studied.Millimeter wave high-gain integrated substrate gap waveguide slot antenna and integrated substrate gap waveguide band-stop filtering antenna are proposed.The ISGW slot antenna was realized with peak gain of 10 d B and fractional bandwidth of 43%.Without extra circuit,the CSRR was introduced into the feeding rectangular patch of ISGW slot antenna,realizing the first-and second-order band stop filtering characteristics of the antenna.The proposed ISGW band stop filtering antenna has the advantages of high passband gain,sharp gain drop in stopband,and wide stopband.3.Study on the integrated substrate groove gap waveguide.The integrated substrate groove gap waveguide and bend waveguide was proposed firstly.Then the transmission mechanism of integrated substrate groove gap waveguide was studied in detail and the theoritical formula of characteristic impedance of ISGW groove gap waveguide was derived.Finally,integrated substrate groove gap waveguide was applied to design a thirdorder bandpass filter.Theoretical design,full-wave simulation and machining test were carried out for the theoretical and applied research.The comparison of the simulated result and measured result verified the proposed method of theory and application design.