In this paper, a numerical algorithm for computation of electric and magnetic fields inside a multilayer cylindrical structure with an arbitrary number of homogeneous layers is presented. Each layer can have arbitrary value of electrical conductivity, permeability and permittivity. Theoretical background of the model is based on Maxwell equations where modified Bessel functions have been chosen for solution formulas. Modified Bessel functions are also scaled to avoid underflow/overflow issues. This results in a numerically robust and highly accurate numerical algorithm for computation of electric and magnetic fields inside a multilayer conductor. Using the derived expression for electric field on the surface of the conductor, the formula for per-unit-length internal impedance of the general multilayer cylindrical conductor is also obtained.
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