6. Time-domain measurements

6.1 Context

Generally speaking, when a property of a signal is not visible in one of its two representations (time or frequency), this property is clearly visible in the other representation. The spectrum analyzer thus complements the oscilloscope. Since network analyzers are used to measure transfer functions as a function of frequency, there is no specific complementary device for measuring impulse responses. Time domain reflectometry processes are limited by the rise times of the test signals and the frequency bandwidth of the oscilloscope. By computationally transforming measured data down to several tens of gigahertz, it is possible to obtain temporal responses impossible to obtain by direct temporal analysis. This time transformation is particularly useful in two cases:...