GSM not detecting station, USRP1, FA-SY1, WBX, DBS

GNU Radio
1

Hello list,

I’m having a lot of trouble here while trying to make openBTS work with
my USRP1
to play with GSMs.
First of all, a little description of my setup:
Software:
openbts-2.6.0Mamou
gnuradio v3.4.0git-130-g207a2ae7
UHD from git
OS: ubuntu 11.04

sudo lsusrp

USRP 0 serial number 4c76a203
RX d’board A: WBX NG RX
RX d’board B: DBS Rx
TX d’board A: WBX NG TX
TX d’board B:

/usr/local/share/gnuradio/examples/usrp/usrp_benchmark_usb.py
Max USB/USRP throughput = 32MB/sec

I’m using a FA-SY clock to get 52Mhz and I followed the guide in 1
I didn’t modify any of the code, since I’m using gnuradio 3.4. (But I
adapted my OpenBTS.config)
When I start openBTS I get the following output:
http://pastebin.com/raw.php?i=nKbG4j3z (I pasted the whole output)

Here is the openBTS config I use:
http://pastebin.com/raw.php?i=aUQfYWGu
(This is the last I used, but I tried several other configs)

My phones cannot find the network, I’m trying with a Motorolla C123,
Nokia 3510i and Nokia E71. I’m not sure where I should search next, I
google’d a lot an read documentation, tried out the fixes described in
forums etc.
Strange behaviour (maybe normal, but not sure):
"sudo usrp_siggen.py --sine
Press Enter to quit: "
No more output…

I would be glad if somebody had an idea where I could look next.

With best regards,
Marc

2

OS: ubuntu 11.04

My phones cannot find the network, I’m trying with a Motorolla C123,
With best regards,
Marc

This isn’t really the correct mailing list for OpenBTS questions, but I
have a couple of suggestions:

o what happens if you undo the clock modifications?
o what do you get if you use something like:

          uhd_fft.py --s 1.0e6 --freq 950e6

Do you get an error, or do you get some kind of reasonable-looking
spectral display?

–
Principal Investigator
Shirleys Bay Radio Astronomy Consortium

3

On Tue, Jun 7, 2011 at 2:02 PM, Marcus D. Leech [email protected]
wrote:

This isn’t really the correct mailing list for OpenBTS questions, but I
have a couple of suggestions:
I wasn’t sure it’s a an openBTS question… as I said I don’t know
where I should look first since I tried so much.

o what happens if you undo the clock modifications?
o what do you get if you use something like:

         uhd_fft.py --s 1.0e6 --freq 950e6

Do you get an error, or do you get some kind of reasonable-looking
spectral display?

I cannot find any uhd_fft.py, I have:
usrp_fft.py
but it isn’t aware of any flag that could be similar to --s…

Where can I find that tool?

Thanks for the reply

4

On Tue, Jun 7, 2011 at 3:28 AM, Paul L. [email protected]
wrote:

Hello list,

I’m having a lot of trouble here while trying to make openBTS work with my USRP1
to play with GSMs.

This question belongs on the OpenBTS list.

RX d’board B: DBS Rx
TX d’board A: WBX NG TX
TX d’board B:

The combination of version 2.6.0-Mamou and WBX isn’t supported.
Official releases and the mainline tree only support operation with
dual RFX900/1800 d’boards. Understandably, this can be easily missed
when browsing the wiki page. The FAQ, however, makes this clear and
provides a solution for the WBX.

http://gnuradio.org/redmine/wiki/gnuradio/OpenBTSFAQ

/usr/local/share/gnuradio/examples/usrp/usrp_benchmark_usb.py
Max USB/USRP throughput = 32MB/sec

I’m using a FA-SY clock to get 52Mhz and I followed the guide in [1]
I didn’t modify any of the code, since I’m using gnuradio 3.4. (But I
adapted my OpenBTS.config)
When I start openBTS I get the following output:
http://pastebin.com/raw.php?i=nKbG4j3z (I pasted the whole output)

These messages are normal. Read the TRX log and you might find a
RXTUNE error, which will be the only sign that something is wrong.

Here is the openBTS config I use:
http://pastebin.com/raw.php?i=aUQfYWGu
(This is the last I used, but I tried several other configs)

Nothing wrong here.

I would be glad if somebody had an idea where I could look next.

http://gnuradio.org/redmine/wiki/1/OpenBTSUHD

Thomas