Re: [Discuss-gnuradio] Log raw data from the usrp_spectrum_sense.py

[Marcus Müller]

Hi Leo,

thanks for following up on this!
I'll just comment in your reply; I hope that is OK for you.

On 12/04/2014 06:05 PM, Leo Yang wrote:
> Hi sir,
> I'm using USRP2 now, as the sample rate is limited to 25MHz for 16bit
> sample, I thought it can only sweep 25MHz at one time, but when u said USRP
> source can get as much bandwidth at once, it confused me. 
Yes, the instantaneous maximum bandwidth with 16bit over Gigabit
Ethernet is 25MHz. But: That is not "sweeping", it's just sampling that
much bandwidth at once.
> The Wi-Fi frequency is from 2.38GHz to 2.42GHz,which 25MHz is not enough for
> such large bandwidth. Or is there any misunderstanding of these concept?
I don't think you're misunderstanding :)
A standard 802.11g channel is only rougly 20MHz wide, the 802.11n
transmissions might be twice as wide, so I guess this was my
misunderstanding.

I'm understanding now that you want to have a sweeping spectrum
analyzer; usrp_spectrum_sense implements that, but in a manner that does
not use timed commands, which is kind of undesirable for a
However, in the gr-uhd/example/grc folder, you will find an example,
called uhd_msg_tune.grc, which behaves a bit similar to
usrp_spectrum_sense, and you could connect a metadata file sink parallel
to the QT gui sink.

Greetings,
Marcus