Re: [Discuss-gnuradio] The noise power of the USRP

[Marcus D. Leech]

On 12/20/2015 10:42 PM, w xd wrote:
> Thanks so much.
>
>             If in a general indoor environment(no people),we just use 
> a usrp as a receiver and in a quiet frequency band,have someone have the
> general data?Can you give a non-official data?around -80dbm?or -70dbm?
>
>             Or how to measure it?What is the true way to measure it?
Use a calibrated noise source.  Take a spectrum measurement.    Now take 
another measurement with your antenna plugged in.

If you know what the noise PSD is of the noise source, then based on the 
difference between noise source and antenna-plugged-in, you
  can calculate the ambient noise PSD.