Using the GaussNoise 'Amp' parameter input

Tech Note: TN0076
Product: RPvdsEx
Version: All
Date Added: 2003-03-12


In RPvdsEx, the GaussNoise component generates noise that varies in amplitude. The variation in amplitude is normally distributed. The Amp parameter determines the standard deviation of the underlying Normal distribution. Under normal conditions the mean of the signal would be zero. However, you can use the shift parameter to change the mean of the signal.

As a rule of thumb, 68% of the function output will be within one standard deviation, or ±{Amp} volts rms. Likewise, 95% and 99.7% of all values generated by GaussNoise will be ±2 and 3 standard deviations from the mean, respectively.

For example, if Amp is 2.2, then 68% of the time the output will be some value between ±2.2 Vpeak. It follows that there is a roughly 4% chance that the output will be as high as ±4.4 Vpeak. Of course, the probability of the output clipping at ±10 Vpeak is not zero but will occur less than 0.0003% of the time.