MATLAB Software and FDTD Algorithm for 3D Coaxial Resonator Cavity Electromagnetic Field Simulation

In this project, we utilize MATLAB software and the Finite-Difference Time-Domain (FDTD) algorithm to solve electromagnetic fields in three-dimensional coaxial resonator cavities. For this implementation, we first establish the fundamental understanding of coaxial resonator cavities and their electromagnetic characteristics. The MATLAB code structure includes grid generation, material property assignment, and field update equations based on Maxwell's equations discretized using central difference approximations.

Our implementation considers multiple critical factors such as the geometric configuration of the coaxial resonator cavity (including inner and outer conductor dimensions), excitation frequency of electromagnetic waves, and boundary condition handling. The FDTD algorithm implementation features Yee cell discretization with staggered electric and magnetic field components, time-stepping using leapfrog scheme, and perfectly matched layer (PML) boundary conditions to minimize reflections.

The source code solution involves iterative field updates through electric and magnetic field update loops, incorporating conductivity and dielectric constant parameters. Key MATLAB functions include meshgrid for spatial discretization, array operations for efficient field calculations, and visualization tools for analyzing field distribution patterns. Results are analyzed through frequency domain transformation using Fourier analysis and optimization of cavity parameters for resonance characteristics.

This project demonstrates practical application of MATLAB and FDTD methodology while providing deep insights into the electromagnetic properties and operational principles of coaxial resonator cavities, including quality factor calculation and mode identification techniques.