A PARTIALLY FERRITES BEADED WAVE-GUIDE APPLICATOR FOR LOCAL HEATING OF TISSUES

A partially ferrites and dielectric loaded water filled waveguide appl icator is presented which can be used for microwave heating of tissues . The applicator can change its heating pattern by changing the extern al DC magnetic field applied to the ferrites. The electromagnetic (EM) field distribution inside the applicator is obtained theoretically an d the simulated EM field inside the applicator is checked experimental ly using 430 MHz. Furthermore, on the basis of the EM field distributi on inside the applicator, simulations of SAR distribution inside lossy homogeneous human tissue as muscle are performed using finite differe nce time domain (FD-TD) method. Simulated data of Specific Absorption Rate (SAR) distribution is compared with the experimental ones. Simula tions of temperature distribution are also performed using heat transf er equation. Simulated data of temperature elevation distribution is c ompared with the experimental ones. The simulated results agree well w ith the experimental ones and it is confirmed that the heating pattern can be changed by external DC magnetic field applied to the applicato r. The results obtained here show that the partially ferrites and diel ectric loaded water filled waveguide applicator which operates at 430 MHz can change its heating pattern without changing its setup and can heat local target on the human body for hyperthermia treatment.