Stimulus-Response MeasurementsN O T E
This application should only be performed using an HP 8591C cable TV analyzer equipped with Option 011.
What Are Stimulus-Response Measurements?
Stimulus-response measurements require a source to stimulate a device under test (DUT), a receiver to analyze the frequency-response characteristics
of the DUT, and, for return-loss measurements, a directional coupler. Characterization of a DUT can be made in terms of its transmission or reflection parameters. Examples of transmission measurements include flatness and rejection. A reflection measurement is return loss.
A spectrum analyzer combined with a tracking generator forms a stimulus-response measurement system. With the tracking generator as the swept source and the spectrum analyzer as the receiver, operation is analogous to a single-channel scalar network analyzer. A narrow-band system has a wide dynamic measurement range, but the tracking generator’s output frequency must be made to precisely track the spectrum anaJyzer’s input frequency. This wide dynamic range will be illustrated in the following example. Figure 5-3 shows the block diagram of a spectrum-analyzer and tracking-generator system.