The study on the dualband filter with common cavity

This paper introduces a method on the dualband filter with common cavity, which is based on the coupling matrix of the General Chebyshev filter, and then writing a matlab program can help us to get the parameters that we need more easier. In this article, the transmission band of the dualband filter is independently controlled. It can respectively by means of adjusting the coupling coefficients between the common cavity and the resonant units of the first passband filter and the second passband filter. At the same time, cross coupling is introduced in the passband filter, which is a good way to reduce the filter size. To verify the paper work, a dualband filter with common cavity design is introduced in the paper, whose test results and simulation results are perfectly identical with each other.