Excitation and propagation of whistler waves in a magnetoplasma in the presence of a cylindrical duct with decreased density

Excitation and propagation of whistler-mode waves in an unbounded magnetoplasma in the presence of a cylindrical duct with decreased plasma density are studied. Using a rigorous solution for the total source-excited field comprising both the discrete and continuous parts of the spatial spectrum of waves, the radiation resistance of a source in the form of a loop antenna is determined. Conditions have been revealed under which the power radiated from the loop antenna immersed in a decreased-density duct is dominated by the contribution of either discrete-or continuous-spectrum modes.