Research On Millimeter - Wave Filter Of Integrated Waveguide

With the widespread use of wireless communication, microwave components are developing toward miniaturization, high frequency and integration. Substrate Integrated Waveguide (SIW) is a new type of planar transmission structure, which has the advantages of both traditional rectangular waveguide and micro-strip line structure. With the maturity of the theory, the practical use of SIW is widely spread. On the basis of substrate integrated waveguide, the paper researches into the millimeter wave band pass filter and microwave duplexer.First, the paper describes the background and significance to understand the importance of microwave millimeter wave frequencies of modern communication and introduces the division of microwave frequencies and the characteristic of frequency spectrum and then presents the history of microwave and millimeter wave, filter and duplexer.Next, the paper focuses on the theoretical framework of filter which includes the classification and the related technical indicators. Then the paper introduces several types of the normalized low-pass filter prototype and the conversion of low-pass prototype to high-pass, band-stop frequency and band pass in particular. Later the paper analyzes the coupling of filters’ cavity, coupling coefficient and the way of coupling.Then, the paper gives a brief introduction of related information of SIW and the design of SIW millimeter wave filter. After referring to some resources, we got the equivalent formula between rectangular waveguide and SIW, and understood the transition between SIW and external flat structure. Through experiments, we knew the hole radius, the spacing between cavity and hole, and how to add the zero point. At last, we finished the V band millimeter wave SIW filter design; its band-pass frequency is 61GHz-66GHz and its volume is 2.64 mm X 2.64 mm X 0.24 mm. Besides, we completed the design of W band millimeter wave SIW filter; its band-pass frequency is 95GHz-104GHZ and its size is 3.4 mm X 1.36 mm X 0.134 mm.Finally, the paper concentrates on duplexer and design of microwave duplexer of SIW. The classification and the design way of duplexer are clarified in the paper, especially all complementary duplexer and series-parallel connection band-pass filter. To finish the design of duplexer, we designed two different frequencies band-pass filter. At last, we finished the SIW duplexer, its band-pass is 7.6GHz-7.8GHz and 8.15GHz-8.35GHz and its size is 47.64mm X 62mm X 0.807mm.