Influence Of Structure Accuracy On The Performance Of Microwave Filters

This paper researches on the impact of structure accuracy of microwave filters on their electrical properties, in view of capacitive irises in rectangular waveguide and coaxial filters.First, the polygon discretion method is proposed, in which irregular waveguide patches are equivalent to discrete waveguide steps. At the same time, the mode-matching method is introduced to analysis the relationship between the structure accuracy of irregular waveguide patch and its transmission characteristics. Simulation and experimental results show that this method is effective.Second, the relationship between the structure accuracy and electrical properties of the cavity filters are studied by applying mathematical statistics methods. For coaxial filters, simulation models are established, uniform test method data sets are obtained by changing the structure accuracy of the coaxial filters, partial least-square regression method of mining is applied to obtain the relationship between the mechanical structures of coaxial filters and their electrical properties.Finally, in view of coaxial tunable filters, a reasonable amount of screw tuner is determined to achieve the required performance indicators by optimizing method, based on the model of the relationship between the amount of screw tuner and electrical properties. The simulation results show that this method is effective.