Re: [Discuss-gnuradio] Noisy source block

[Marcus Müller]

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Hi 猪猪猪猪猪猪头,

you've replied to the wrong thread; however:

dB is *always* a relative measure. You can't output dB; it always has
to be dB in relation to something.

The parameter of the noise source is amplitude.
Like Martin, if I *want* to stick a physical entity to it, it would be
voltage. Usually, I don't -- the noise source just outputs a
realization of a complex random process; it's just numbers without unit.

I'm under the impression you're mixing up absolute noise power, noise
variance, and SNR; for SNR, which is a ratio, dB does indeed make
sense. However, you don't get a noise source that generates a certain
SNR, because that depends on the signal power, and is something that
you/your application has to calculate.

Greetings,
Marcus

> hi ,Martin Braun well ,in my impression, the unit of is noisy is 
> dB,so i feel fuzzy
about the volt,
> thanks for your reply!
> 


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