TLM modelling of loaded microwave applicators with an excitation through the waveguide

In this paper, a real microwave applicator with a waveguide used to launch the energy from the source into the cavity is analyzed using 3D TLM method. First, a loaded cavity is analyzed using conventional TLM simulator with an impulse excitation. For modelling of loaded cavity without feed attached, in order to avoid using of non uniform mesh, TLM algorithm with Z transform is applied. Obtained results are compared with referent values from mu Wavelab commercial software based on FEM method. Furthermore, in order to investigate the influence of the feed waveguides to the number of resonant modes inside the cavity, microwave applicator with four feed waveguides is modelled. Also, TLM method is applied to the single-feed cavity, and a very good agreement between simulated and experimental results is achieved.