Keysight Technologies N5511A, User Manual

Page: 183 / 369

N5511A Phase Noise Test System User’s Guide 183
Residual and Additive Noise Measurement Fundamentals
Calibrating the Measurement
Figure 7-13 shows how a single channel measurement is configured using a
phase modulator and how the tone is measured using this setup, a concept
that can be extended to a dual channel setup as well by splitting the phase
modulator to both LO channel paths.
Figure 7-13 Single Channel Measurement with Phase Modulator
Figure 7-14 shows the setup for a dual channel residual measurement, where
the stimulus provides the carrier that is modulated to perform the
double-sided spur cal. If the stimulus is not capable of being phase modulated,
a separate phase modulator can be used.
Figure 7-14 Dual Channel Residual Measurement
See the absolute measurement calibrations section on page 86 for more
detailed theory about how double-sided spur calibration works.