Multiport VNA measurement uncertainty - Signal integrity applications

Abstract

Vector network analyzer (VNA) measurements are often stated without an indication of the estimated uncertainty. Understanding the uncertainty can lead to understanding the sources of uncertainty and targeting improvements in the metrology to address the largest sources. Connector repeatability in manually probed measurements can be a primary source of uncertainty with this metrology. A measurement capability assessment provides the method for evaluating the total uncertainty. Evaluation of the probe launch and cable movement provided substantial opportunities to improve the capability. Implementing improvements identified through the measurement capability assessment (MCA) process has resulted in a doubling of the highest frequency where the metrology is deemed capable.