Abstract :
In RF and microwave engineering, vector network analyzers (VNAs) are employed to characterize one-, two- and multi-port networks in terms of scattering parameters (S-parameters). Over the past years, VNA instrumentation has been established to perform waveguide measurements at frequencies of several hundreds of GHz. At such higher frequencies, it becomes difficult to verify the calibration of the VNA system in order to achieve accurate measurements and traceability to the International System of Units (SI). In waveguide systems, such verification can be carried out using waveguide sections with reduced cross-sectional dimensions. However, at higher millimeter and sub-millimeter frequencies, it is mechanically challenging to manufacture the required high precision waveguide sections because the dimensions of the waveguide aperture become very small. Currently, verification standards for measurements above 110 GHz are either not available or do not provide traceability to the SI.
