Quasi-Analytical Design of Commensurate-Line Waveguide Band-Pass Filters

In this paper, a quasi-analytical design method for commensurate-line waveguide band-pass filters is proposed. The novel design methodology allows designers to obtain the final band-pass filter structure in a negligible time since neither electromagnetic simulations nor optimizations are needed to compute the physical dimensions of the device. The proposed procedure is based on mimicking the magnitude and phase of the reflection coefficients in each discontinuity with closed-form expressions. The feasibility of designing commensurate-line waveguide band-pass filters with the proposed method has been demonstrated through a Chebyshev chained function waveguide band-pass filter whose simulated frequency response is very close to the ideal one.