LabVIEW
Uniform White Noise vi parameters
@malkoba wrote:
Hi
What is meant by seed in the Uniform White Noise vi. in labview. What is the effect of sample rate and nuber of samples on the noise waveform and the output power?
Thanks
Mal
The seed is a number sent to the Pseudorandom noise algorithm to start its sequence. If left blank a "random" number is generated and sent to start the prn generator. On subsequent calls to the Uniform White Noise Generator it continues the previous sequence (it is pseudorandom after all). I'm not seeing a sample rate on my version (7.1) only sample number. The default for sample number is 128, which is a power of two, something that FFT's etc. are happier with than non powers of two. As far as the effect on the noise waveform, it just defines the length up to max memory or 2^31-1. What do you mean output power? For white noise you would have to define a bandwidth in which you were measuring the noise and then average over a long time. Try putting together a simple experiment and seeing what effects changing the values has. You don't have the base package, if you have the Uniform White Noise vi, so you probably have the Power spectrum vi, etc. Wire the UWN into a power spectrum, then drop a waveform graph on the front panel and look at the resulting spectra.
P.M.
