Yes, I think I only need to know the power strength and don't need to decode the signals for searching the spectrum holes. I read the usrp_spectrum_sense.py. I wonder how I can draw a spectrogram through this program. I think the line 145 shows the source is the USRP. However, I have no idea where the destination is. I thought I can get the data through GNU Radio and then use Matlab to draw the spectrogram to show the spectrum holes. In line 193, the connection seems without the destination. How do you guys use this code to draw the spectrogram?
| 145 |
self.u = usrp.source_c(fusb_block_size=options.fusb_block_size, |
| 146 |
fusb_nblocks=options.fusb_nblocks) |
| 193 |
self.connect(self.u, s2v, fft, c2mag, stats) |
Thank you,
Roy
Goodman Roy wrote am 2008-07-15 00:26:
> Hi all,
>
> I would
> like to know if it is possible to sense the whole
> band,2.4-2.4835GHz, through the USRP? However, the ADC can only
> support 64Msamples/sec. How can I scan the whole ISM band and draw the
> spectrogram of the ISM band,2.4-2.4835GHz, through the USRP?
You can receive 32MHz at a time, but you are limited to 8MHz through the
USB bus. You cannot scan the whole 2.4Ghz ISM band at a time, but you
can step through it. If you want to detect unused frequencies you'd
probably just want to calculate the power over a reasonable time
interval to decide if some is using the band in question.
You may want take a look at
gnuradio-examples/python/usrp/usrp_spectrum_sense.py [1]
Patrick
[1]
http://gnuradio.org/trac/browser/gnuradio/branches/releases/3.1/gnuradio-examples/python/usrp/usrp_spectrum_sense.py--
Engineers motto: cheap, good, fast: choose any two
Patrick Strasser <patrick dot strasser at student dot tugraz dot at>
Student of Telematik, Techn. University Graz, Austria