Traceable high-precision impedance measurements for the millimetre-wave band using dielectric waveguide transmission lines

Abstract

Currently, the UK's national standards for impedance measurements are only available for frequencies up to 50 GHz in a coaxial line and 110 GHz in a metallic rectangular waveguide. No standards exist above these frequencies. A need to provide measurement standards and measurement assurance above these frequencies has led to research into a new form of impedance standard for precision metrology applications across the entire millimetre-wave band and perhaps beyond (i.e. extending to at least 300 GHz). We report the development of the new standards and other devices that utilise a dielectric waveguide as the transmission medium, and we show how these standards can be used to calibrate measuring instruments, such as vector network analysers (VNAs), and to provide traceability to national standards.