Determination of performance parameters of an equilateral triangular cavity resonator

Abstract

In this article, a set of closed form expressions is proposed to compute the resonant frequency, unloaded quality factor, equivalent circuit components of cavity, coupling capacitance, external quality factor, input resistance at resonance, input impedance and loaded quality factor of equilateral triangular cavity resonator. The closed form expressions are based on the following classical methods: (i) the waveguide model for resonant frequency and unloaded quality factor. (ii) the circuit theory model is employed to determine the coupling capacitance and the external quality factor, (iii) the transmission line model is used to compute the input resistance at resonance and (iv) the parallel resonant R-L-C circuit model is used to derive the input impedance expression. The closed form expressions are simple, fast and focused on different TE and TM modes. The computed values are validated with simulation and experimental results.