TLM modeling of the circular cylindrical cavity loaded by lossy dielectric sample of various geometric shapes

The modeling of the cylindrical metallic cavity with circular cross-section loaded by lossy dielectric sample of various geometric shapes is done by using the Transmission-Line Matrix (TLM) method. For modeling purposes, a hybrid symmetrical condensed node (HSCN) in cylindrical coordinates, developed and implemented in the appropriate software, is applied. The proposed TLM models for several characteristic geometric shapes of the lossy dielectric sample are described in detail, the modeling process is discussed and the influence of the load form on the resonant frequencies of the cavity is investigated. In addition, the applied TLM approach is experimentally verified for two cases of cavity load form.