Title :
Electromagnetic energy deposition in co-axially layered biological media placed within a tape helix for microwave hyperthermia
Author :
Pathak, S.K. ; Singh, S.P. ; Jha, R.K.
Author_Institution :
Dept. of Electron. Eng., Banaras Hindu Univ., Varanasi, India
Abstract :
A general field theory has been developed and the resulting relation is numerically solved for EM energy deposition in bone, muscle, fat, and skin biological layers placed within tape helix with ten co-axially layered dielectrics at different spot frequencies in the range of 0.3 to 3.0 GHz. The electric and magnetic fields in every dielectric layer is formulated in terms of complex modified Bessel functions and complex exponentials i.e. in terms of complex radial and axial propagation constants for the azimuthally symmetric mode and higher order spatial harmonics. The normalized patterns of specific absorption rate (SAR) across the cross-section of helical structure for n=0 mode and for combined mode by taking 100% excitation coefficients of EM power for n=0 and different coefficients for n=1 mode at said frequencies are computed and presented
Keywords :
Bessel functions; biological effects of microwaves; bone; hyperthermia; microwave heating; muscle; radiation therapy; skin; 0.3 to 3.0 GHz; EM energy deposition; axial propagation constants; azimuthally symmetric mode; bone; co-axially layered biological media; complex exponentials; complex modified Bessel functions; complex radial propagation constants; dielectric layer; electric fields; electromagnetic energy deposition; excitation coefficients; fat; helical structure; higher order spatial harmonics; magnetic fields; malignant tumors; microwave hyperthermia; muscle; normalized pattern; skin biological layers; specific absorption rate; spot frequencies; tape helix; Biological system modeling; Bones; Dielectrics; Frequency; Hyperthermia; Magnetic fields; Muscles; Permittivity; Propagation constant; Skin;
Conference_Titel :
Engineering in Medicine and Biology Society, 1995 and 14th Conference of the Biomedical Engineering Society of India. An International Meeting, Proceedings of the First Regional Conference., IEEE
Conference_Location :
New Delhi
Print_ISBN :
0-7803-2711-X
DOI :
10.1109/RCEMBS.1995.533020