Air-Filled Circular Cavity Resonator Calculator

This page provides an air-filled circular cavity resonator calculator. The calculator determines the resonant frequency, unloaded quality factor, and half-power bandwidth.

Important: This calculator is specifically designed for the TM 010 mode only. Therefore, n = 0, p = 1, and q = 0, which results in X 01 = 2.405.

EXAMPLE:

• INPUTS:

  • a (radius) = 5 cm
  • d (length) = 10 cm
  • Conductivity = 6.17E7

• OUTPUTS:

  • Resonant frequency (GHz) = 7.215
  • Surface resistance (Ohm) = 0.0214
  • Unloaded Quality factor = 14060.44
  • Half-power bandwidth = 513.141 KHz

Circular Cavity Resonator Equation

As we know, a cavity exhibits resonant properties at specific frequencies (i.e., λ g /2), leading to the formation of a standing wave pattern along the guide length. When the waveguide is circular, it’s called a circular cavity.

In a circular cavity, a section of the waveguide is closed by two perfect conductors positioned at a certain distance from each other.

The following equation/formula is used for the air-filled circular cavity resonator calculator.