MODAL COMPOSITION OF RADIATION EXCITED BY LOCALIZED SOURCES WITH PARABOLIC REFRACTIVE INDEX PROFILE
A. B. Valyaev, I. N. Sisakyan
Modal composition is studied for a waveguide with parabolic refractive index profile through the known directivity diagram of a localized source. Conditions have been determined under which the angular distribution of the localized source field is describable by a decomposition in terms of coherent states. Explicit expressions have been found for the coefficients of waveguide mode excitation, and for the case of non-directed sources a recursive relation was determined for their calculation. The mode composition of a dipole source is shown to be basically dependent on its position with respect to the waveguide axis. It is also demonstrated that, even in the case of a non-directed radiator, selective excitation of individual groups of waveguide modes is feasible.
© 2009, IPSI RAS
151, Molodogvardeiskaya str., Samara, 443001, Russia; E-mail: firstname.lastname@example.org ; Tel: +7 (846) 242-41-24 (Executive secretary), +7 (846) 332-56-22 (Issuing editor), Fax: +7 (846) 332-56-20