Phase Noise Spectrum (802.11n/ac/ax)
shows the phase noise calculated from the data in the measurement interval. This trace is shown with a Log X-axis and Log Y-axis by default. In this case, each point represents the noise density of the frequency band centered at that point, whose width is +/- half the spacing between points.
The phase noise spectrum shows the noise from near DC to half the signal bandwidth (the phase noise calculation includes both sides of the frequency spectrum around DC).
When shown in the LogMag trace format, the Y-axis units are dBc/Hz amplitude in a 1 Hz bandwidth relative to the carrier. The "c" in this unit means "relative to the carrier" and has been added for display purposes since this is the way Phase Noise plots are commonly shown (and the VSA's calculation of phase noise implies the "c," but the VSA would not include "c" in the units normally). The "c" does not appear in other trace formats' units.
Averaging
When or averaging is enabled, this trace will instead use simple vector averaging to average the underlying complex data. The other type of averaging supported by this trace is /.
See Also
