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Simulators >> AMS Simulators >> Amplitude of noise processes
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Message started by Stefan on Jan 22^nd, 2008, 2:46am

Title: Amplitude of noise processes
Post by Stefan on Jan 22^nd, 2008, 2:46am

Hi,
I'm kinda confused with noise processes :)

When looking at Chen's "paper Modeling RF Systems",

noise voltage is added as white_noise(pwr,'name'), where
pwr equals (NF-1)*4*K*T*R

Does anyone know how to calculate the voltage AMPLITUDE of the white_noise function at a time t ?
(yes, I know that it's a random process)

I'm trying to implement the white_noise function using a dist_normal process where I can't provide any power argument ...

Regards,

Stefan

Title: Re: Amplitude of noise processes
Post by Frank Wiedmann on Jan 22^nd, 2008, 5:52am

The rms noise voltage equals the standard deviation of the normal distribution.

Title: Re: Amplitude of noise processes
Post by Jess Chen on Jan 22^nd, 2008, 7:52pm

Stefan,

You can compute the standard deviation (i.e. rms noise) of the noise from the noise figure and sample rate. If you are using a baseband equivalent model and the expressions I give in my paper, you need to use half the sample rate as the bandwidth when computing the standard deviation. You should also use $rdist_normal instead of $dist_normal. The "r" gives you a random real number. Without the "r" you get integers.

-Jess