RF & Microwave Resonator Simulation

This note uses the RF & Microwave module to simulate a symmetric dielectric resonator filter with coaxial couplers, computing S-parameters, pass-band response, attenuation and field distributions, and comparing results with published data.

This application note presents a resonance study of a cylindrical cavity using EMWorks. The model is filled with air and bounded by Perfect Electric Conductor (PEC) or Imperfect Electric Conductor (IEC) walls to capture conductor and dielectric losses. EMWorks’ eigenmode solver extracts resonant frequencies, electric field distributions, and Q-factors for user-specified modes, with mesh refinement on the curved cavity surfaces to balance accuracy and runtime. Results include fringe and section-clipped field plots and mode tables that can be exported for further use in filter, oscillator, or tuning element design.

This application note analyzes a spoke resonator designed for a nominal 325 MHz operating frequency. Using 3D electromagnetic eigenmode simulation, the first resonant frequency and associated quality factor are extracted and compared directly with measured data. The simulated fundamental mode at 323.02 MHz closely matches the test value of 324.73 MHz, validating both the CAD model and setup. Section plots of electric field and magnetic field intensity provide insight into field distribution inside the cavity, helping engineers refine geometry, losses, and coupling for particle acceleration and RF cavity applications.