Accuracy and Repeatability in Time Domain Network Analysis

This paper examines the importance of measurement repeatability in time domain network analysis and includes an analysis of the limitations imposed on theoretical accuracy by measurement noise. A closed-loop correction algorithm implemented in a fast, equivalent-time sampling, time domain reflectometer improves source timing accuracy, the dominant cause of nonrepeatability. An example measurement of attenuation in a 3.5 mm coaxial air-line demonstrates performance approaching this theoretical noise limit and the limits imposed by connector repeatability.