Traceable reflection coefficient measurements in coaxial line at MF and HF

This paper describes a measurement capability developed at NPL Malvern to provide traceability for complex voltage reflection coefficients at MF and HF (300 kHz to 30 MHz). A vector indicating automatic network analyser (ANA) is used as a reflectometer and is calibrated in terms of a calculable open-circuit, a short-circuit and a characterised load. The load is characterised using a frequency-invariant equivalent-circuit model derived from measurement data at higher frequencies. The equivalent-circuit details are given, along with results achieved using this capability.<>