This paper presents a novel contribution to the analysis of skin-effect like phenomena in radially inhomogeneous tubular geometries that fit in the category of Euler-Cauchy structures (ECS). The advantage of ECSs is that solutions for the electromagnetic field can be described by very simple closed form formulae. This work addresses the evaluation of the per unit length complex magnetic reluctance of tubular ferrites, taking into account that their complex permeability strongly depends on the frequency. The motivation for this research is linked up with the nascent theory of magnetic transmission lines (MGTL), where the wave guiding structure is made of a pair of parallel ferrimagnetic pieces, and whose performance is critically dependent on the complex magnetic reluctance of its component pieces. The analysis presented is mainly focused on high frequency regimes up into the GHz range.
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