Re: [Discuss-gnuradio] Receiver sensitivity/noise floor...

[Matt Ettus]

On 02/15/2010 10:11 PM, Ian Holland wrote:
> Hi All
>
> Does anybody have information on what the receiver sensitivity or noise
> floor is for the XCVR2450 boards with a USRP2. I need to know at what
> level a spurious signal from another source could cause noticeable
> interference to a desired signal.


There is no absolute receiver sensitivity measurement.  You need to 
specify your modulation, coding, data rate, and how good your software 
implementation is.

Noise floor is also something that requires additional information to 
compute an answer.  You need to specify a bandwidth.

It is for the above reasons that sensitivity and noise floor are not 
useful in describing a software radio, since you can do so many 
different things at different bandwidths.  Noise figure is the only 
absolute measurement which characterizes a receiver independent of those 
other factors.  At high gain, the XCVR has a noise figure of 5 to 10 dB 
depending on your frequency.

Your second question about spurious signals interfering with a desired 
signal has nothing to do with the first question, though.  Interference 
from spurious is a completely different phenomenon from noise, noise 
figure, sensitivity, etc.

Matt