Characteristic impedance of a coaxial system consisting of circular and noncircular conductors

Two types of equivalent eccentric coaxial lines are described whose eccentricities vary with the ratio of inner and outer conductors, for a coaxial system consisting of circular and noncircular conductors. The equivalent lines can provide a smooth transition between extremes of a small wire and a wire near contact. The results obtained are simple analytical expressions for fast computation of the characteristic impedance or for the computer-aided design (CAD) of coaxial components. The accuracy of the expression is confirmed by comparison with accurate numerical data.<
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