Title :
Attenuation characteristics in confocal annular elliptic waveguides and resonators
Author :
Gutiérrez-Vega, Julio C. ; Rodríguez-Dagnino, Ramón M. ; Chávez-Cerda, Sabino
fDate :
4/1/2002 12:00:00 AM
Abstract :
The perturbation method is used to obtain the attenuation constant and Q-factor of several TEM, TE, and TM modes in confocal annular elliptic waveguides (CAE-Ws) and confocal annular elliptic resonators (CAE-Rs). Normalized attenuation and Q-factor charts are given for a variety of possible combinations of the focal distance and the eccentricities. Comparisons between the first higher mode in a CAE-W and a coaxial waveguide with the same cutoff frequency and cross-sectional propagating area reveals a lower attenuation in elliptic geometry. Consequently, the Q-factor in a CAE-R is 20%-40% greater than a Q factor for a coaxial resonator with the same volume and resonant frequency
Keywords :
Q-factor; cavity resonators; coaxial waveguides; eigenvalues and eigenfunctions; electromagnetic wave absorption; perturbation techniques; waveguide theory; Fourier series; Mathieu functions; Q-factor; TE modes; TEM modes; TM modes; attenuation constant; coaxial guides; conducting walls; confocal annular elliptic resonators; confocal annular elliptic waveguides; eccentricities; eigenvalues; focal distance; perturbation method; Acoustic waveguides; Attenuation; Coaxial components; Computer aided engineering; Cutoff frequency; Geometry; Microstrip antennas; Optical resonators; Optical waveguides; Tellurium;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
