Whistler modes of a radially nonuniform cylindrical duct with enhanced density in a nonresonant magnetoplasma

We study the guided propagation of whistler waves along an enhanced density duct in a nonresonant magnetoplasma. Conditions are revealed under which an approximate approach based on perturbation theory can be applied for determining characteristics of the guided modes in the case of a smooth monotonic variation of plasma density across the duct. A good agreement is shown to exist between the results of the developed approximate approach and a rigorous full-wave analysis.