Study On Characteristics Of Miniaturized Microwave Resonant Cavity

The development of small, high-performance microwave filters is a hot research topic. Using three-dimensional electromagnetic field simulation software to analyze and design microwave resonant cavity is an effective way, but its shortcomings are the large amount of computing, time-consuming and increase of product design cycle on simulation of complex microwave devices. For the cavity with simple structure, the method has been introduced in many literatures, but for the cavity with complex structure, there is little research due to lots of analytical works. This paper introduces the coaxial resonant cavity with bended inner conductor on base of simple cavity, make detailed theoretical study, numerical simulation and experiment verification. The major achievements are listed as follows:1. A coaxial resonant cavity with bended inner conductor is presented, use the method of mode matching, and derive the eigenequation which can get frequency precisely, calculate the field distribution and power capacity further. On the solution of cavity frequency, simplifying the complex eigenvalue equations into an equation of cavity end, which optimize the solution process and improve the efficiency.2. Theoretical calculations reveal the higher-order transverse mode characteristics of resonant cavity: the resonant frequency converged with the increase of order. It is time-saving compared with electromagnetic software simulation, can calculate the frequency and other characteristic parameters of a specific size quickly.3. Get a large number of experimental results by using HFSS; compare the calculation results with the simulation results, which shows that the structure with bended inner conductor can not only enable the cavity toward the direction of miniaturization, but also make the field distribution homogenization, gain more power capacity. This conclusion can be used as a reference for the design of miniaturized microwave cavity.