Title :
Generation of a highly focused electromagnetic field in a lossy biological medium by controlling the phase and time excitation of the microwave sources
Author :
Nikita, Konstantina S. ; Uzunoglu, N.K.
Author_Institution :
Dept. of Electr. & Comput. Eng., Athens Nat. Tech. Univ., Greece
Abstract :
A focused electromagnetic field is generated in a layered cylindrical biological tissue model, by using a large number of concentrically placed waveguide applicators and pulsed signals of short pulse width, with a high frequency carrier. To this end, constructive phase interference and time coincidence of pulse modulated microwave signals principles are applied. Numerical results are computed and presented for a three-layer geometry, 20 cm in diameter, irradiated by an annular waveguide array, using 30 elements.
Keywords :
hyperthermia; physiological models; radiation therapy; 20 cm; annular waveguide array; concentrically placed waveguide applicators; constructive phase interference; focused electromagnetic field; high frequency carrier; highly focused electromagnetic field generation; layered cylindrical biological tissue model; lossy biological medium; microwave source phase; microwave source time excitation; pulse modulated microwave signals; pulsed signals; short pulse width signals; three-layer geometry; time coincidence; Biological system modeling; Biological tissues; EMP radiation effects; Electromagnetic fields; Electromagnetic modeling; Electromagnetic waveguides; Pulse generation; Pulse modulation; Signal generators; Space vector pulse width modulation;
Conference_Titel :
Microwave Symposium Digest, 1996., IEEE MTT-S International
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-3246-6
DOI :
10.1109/MWSYM.1996.511222
