An extended time-domain network analysis measurement technique

A novel method of calculating transmission line characteristics using time-domain data is presented. Time-domain network analysis is the spatio-temporal analysis of the response of a circuit to a unit step input. Time-series sampled reflection and transmission data can be transformed to the frequency domain and de-convoluted with the measurement system impulse response function to remove the artifacts of the measurement apparatus. These techniques have, until recently, been used to measure circuit response to very fast edges. Transmission line characteristics have usually been measured using frequency domain techniques because the high-frequency limit characteristic impedance (Z ₀ or the so-called `surge impedance') could only be determined in the frequency domain. An innovative technique is described that permits calculation of the surge impedance using only time domain data. The theory behind the technique is described and an experimental comparison between simulations and the time domain technique is presented