Calibrating a VANA with a slightly lossy beadless coaxial standard line

Use of a beadless coaxial standard line to calibrate a vector-indicating automatic network analyser (VANA) provides for measurement of the voltage reflection coefficient Γ in terms of the mode propagated by that line. Owing to skin effects, the impedance Z _m assigned to that mode differs from that defined for an ideal lossless line of appropriate dimensions, Z_def(=50Ω). The author reports results of expressing the measured Γ in terms of the nominal Z_def for f⩾0.05 GHz, after accounting for the conductor loss by measurements with a type N beadless coaxial standard line