S-parameter measurement with fixture de-embedding is a critical task to address the current challenges of complex systems running at high data rates and high-frequencies. The era of a single engineer doing all the simulations and measurements and controlling every aspect is long gone. Projects require multiple teams sharing component S-parameter files, and multiple people measuring S-parameters with different equipment and fixture de-embedding methods.
In the context of the IEEE P370 standard activities, the members collected data on how measurement results and de-embedding results can vary across different teams. Consistent results are not only determined by the accuracy of the equipment each team uses, but also by other factors such as: how the measurement is set-up, the quality of the cables and connectors used, and the care that was taken during the calibration to name a few of the factors that will be discussed.
In this paper, we present the analysis of the data above. The measurement equipment and fixture de-embedding tools are anonymized. The objective is not to find which setup is better, but to show how much variation can occur when different teams make these kinds of measurements.
In the context of this exercise, we will also discuss some lessons learned, best practices for VNA measurements, and fixture de-embedding that can help make measurements more repeatable.
