Design Of Miniaturized 5G Communication Filter And Antenna Based On LTCC

With the extensive development of fifth generation mobile communication(5G)research,two key device filter and antenna of the RF front-end have become hot spots in terms of miniaturization,integration,and multi-function.Substrate Integrated Waveguide(SIW)has been greatly utilized in the design and application of highfrequency devices due to its advantages of easy fabrication,flexible design and low fabrication cost.Low Temperature co-fired ceramics(LTCC)technology has become an important process for miniaturized device design because of its ability to achieve 3D integration.The combination of LTCC technology and SIW structure has laid a solid foundation for the design of high performance and miniaturized microwave devices.In this thesis,the working principle and design of miniaturized filter and antenna based on LTCC multilayer technology are studied.The main work of this thesis is as follows:1.Research on SIW filter based on LTCC technologyIn this thesis,a variety of coupling topologies are studied and several compact multilayer SIW filters are designed.The first filter based on the coupling resonator theory introduces cross-coupling technology into the filter design of rectangular cavity and circular cavity with center frequency 39 GHz,28 GHz and 31 GHz respectively.Transmission Zeros(TZs)generated outside the passband improve the selectivity of the filter,at the same time confirmed that the filter based on LTCC structure has significant advantages in 3D integration.The second is a full-mode SIW cavity loaded with circular metal and combined with cross-coupled structure to achieve a miniaturized SIW filter design.Finally,aiming at the shortage of traditional cross-coupling that only a pair of TZs can be designed synthetically,based on mixed coupling technology can improve the performance of the filter,a filter that works at 28 GHz and can be used in the 5G communication frequency band is proposed.A mixed coupling structure is constructed by etching Inter-digital Slot-Line on the top metal between the centers of two SIW resonators.Not only a pair of TZs are generated on both sides of the passband of the filter,but also a third controllable TZ is additionally generated at the low frequency,which further improves the selective characteristics of the filter.2.Research on SIW antenna based on LTCC technologyBased on the theory of antenna array,two multilayer antenna arrays with center frequency of 28 GHz in the millimeter wave band are designed.The first antenna is a miniaturized filtering antenna with multilayer structure fed by SIW power divider.The antenna adopts a 2×2 array structure to achieve a high gain.The coupling structure between the power splitter in the bottom SIW cavity generates the filtering effect.The results show that the antenna has the advantages of miniaturization,broadband and high gain.The second is the design of multilayer antenna and array loaded with dielectric resonators.The antenna element structure loaded with a dielectric resonator is fed by the slot on the upper surface of the bottom SIW layer.Its feed structure and radiation element structure can be effectively integrated by LTCC process.Finally,a multilayer SIW antenna array with high gain is designed based on the antenna element.In the feeding part,the antenna array is fed by SIW power distributor.After software simulation,the antenna array has good performance and can be applied as the work requirement of the future 5G system.The thesis has 89 figures,7 tables and 91 references.