Keysight 81150A - Limitations of User-Defined Noise Distributions

Appendix
622
The crest factor of the user-defined distribution is:
2
1
0
minmax
1
2
i
N
i
Sample
N
SampleSample
cf






Where N is either 16384 or 524288 (for 81150A).
7.5.1 Limitations of User-defined Noise Distributions
Introduction
Due to bandwidth limitations of the output amplifier, the measured
histogram does not perfectly match the defined distribution.
The difference between the calculated crest factor of the user defined
distribution and the measured histogram depends on the amplifier path
being used and on the distribution itself.
Example of user
defined distribution
defined by Ramp
waveform
The following example shows a user defined distribution that is defined by a
ramp waveform. This should lead to an equal distribution of all voltage levels
in the output signal. Due to the bandwidth limitations and asynchronous
sampling of the oscilloscope, the measured histogram is not rectangular as
expected.