Design Method of Waveguide Filter Using Coupling Matrix

In this paper, a 10-stage waveguide filter is designed using the coupling matrix method after converting the Chebyshev prototype low-pass filter into an inverter-coupled form through the equivalent circuit conversion method. While the optimization process in the theoretically designed structure is carried out through time and human know-how in the past, this paper shows how to solve it in a sophisticated and efficient way using Synmatrix’s AI tuning program. Through this, we propose a efficient design method for a waveguide filter having a complex coupling structure in the high frequency band. For verification of the design method, tow types of filters are designed and one of the is fabricated. The designed filter has a center frequency of 3.625GHz, a bandwidth of 150MHz, and a reflection coefficient of -20dB in the passband. Another designed filter has a center frequency of 3.84GHz, a bandwidth of 300MHz, and a reflection coefficient of -20dB in the passband. © 2023 Korean Institute of Electrical Engineers. All rights reserved.