Improved Waveguide Calibration of Vector Network Analyzers in WR15

This paper discusses factors affecting the accuracy of Vector Network Analysis in millimeter waveguides. Among these are accuracy improvements provided by a new precision WR15 waveguide flange which maintains compatibility with the current UG-385/U flanges. The new wR15 waveguide flange design offers much improved performance in the frequency range of 50 to 75 GHz. Measurement results for flange repeatability along with accuracy results for residual directivity and source match, both for Maury and UG-385/U standard flanges, are presented.