Modular waveguide filter platform for educational and prototyping purposes

In this paper, a modular waveguide filter platform suitable for educational and prototyping purposes is presented. The waveguide filter platform is dimensioned to work in the F-band (4.9–7.05 GHz). The design of the platform is discussed and versatile application possibilities are shown in many examples. The platform can be used to realize generalized Chebyshev filters with or without cross-couplings by exploiting TE101 and TE102 mode cavities. Transmission zeros can be introduced by the utilization of wires or aperture couplings. Filter topologies based on the extracted pole technique can be examined as well. Small changes in the set-up also allow the realization of a gap waveguide filter, a diplexer set-up as well as filters with frequency-dependent coupling apertures. Most required components can either be purchased cheaply or be manufactured with a three-dimensional printer.

Coupling matrix synthesis of general chebyshev filters

A single optimization algorithm based on SolvOpt that synthesizes coupling matrices for cross-coupled microwave filters is presented. The rules for setting initial values of SolvOpt are proposed to find global minimum of the cost function. SolvOpt method provides faster convergence and higher accuracy to find the final solution compared with hybrid optimization algorithms. Application examples illustrate the excellent performance and the validity of this method.