Hi all,
it seems like supporting the Motorola BTS from OpenBSC is a really big
challenge. Not only are there problems regarding an unknown
configuration database format (see
http://laforge.gnumonks.org/weblog/2011/06/18/)
Dieter has found the following excellent document, which in Chapter 5
describes the architecture of the Motorola specific changes to A-bis:
http://read.pudn.com/downloads61/ebook/212957/SYS01.pdf
Judging from the document:
* there is an unknown 'motorola executive header' in front of RSL
* many RSL standard messages have been replaced by proprietary ones
* they use a mixture of 08.08 (A) and 08.58 (A-bis) information elements
* many features normally found in the BSC are implemented in the BTS,
e.g. the entire CHAN RQD / RSL CHAN ACT / IMM ASS CMD sequence is
done fully inside the BTS.
As a result, I think it will be a quite complex project to support those
BTSs from OpenBSC. It's not just a matter of adding some small
vendor-specific OML messages like with Siemens, Ericsson and ip.access.
While it might still be interesting, I think it's unrealistic to assume
this would happen ahead of the camp [unless somebody finds a compatible
Motorola BSC that they can borrow us for analysis + protocol tracing].
Thus, the focus for the 2011 CCC Camp is now back to ip.access. The
main issues we will be facing is on the RF side, i.e.
* RF PA for the TX side
* combining the PA outputs to be transmitted on one antenna
* filter + LNA for Rx side
* splitting the Rx signal
As indicated previously, I would love to see something like two BTS
with three TRX each.
If we'd recycle the duplexer/combiner blocks from the Motorola BTS, we
could do something like three sites with 2 TRX each. (as they can only
combine two TRX).
We _might_ also be able to re-cycle the TX PA from the Motorola CTUs, at
least on the RF side it would be pretty easy to drive them from a
nanoBTS rather than its internal source (as there's a connector).
The bigger question is how do we get the controller logic of the PA into
a state that the PA is actually enabled and active...
Regards,
Harald
--
- Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/
============================================================================
"Privacy in residential applications is a desirable marketing option."
(ETSI EN 300 175-7 Ch. A6)
Hi zecke and others,
I may have found a cause of one of the problems that we've been
experiencing in nanoBTS bring-up, at least at some point in the past.
The problem could be observed/described as: During the first OML
connect of the nanoBTS, OpenBSC fails to bring it up completely. Second
and successive connects worked fine.
What I have just noticed is that we never re-set the NM state
information for the 12.21 MOs inside OpenBSC. This means, if the A-bis
link is lost, the old state information continues to exist.
I guess it would be cleaner to simply re-set all the nm_state strucures
that are part of the 'struct gsm_bts', gsm_bts_trx, etc. when the A-bis
link is lost.
As I'm working in this area right now anyway, I intend to produce a
patch addressing the issue.
But now that I think more about it: I guess it is unrelated to the old
problem, as a typical work-around was to re-start OpenBSC, at which time
all state is re-set again.
Regards,
Harald
--
- Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/
============================================================================
"Privacy in residential applications is a desirable marketing option."
(ETSI EN 300 175-7 Ch. A6)
Dear all,
I want to buy some nanoBTS or HSL 2.75G picocell .
Is there any body who wants to sell nanoBTS or HSL 2.75G picocell ?
Looking forward for any offer .
Regards,
jngpz(a)163.com
2011-06-19
Dear Developers,
I mentioned earlier that I found a tutorial in which we read that this cell
is within the box's serial port.
I found him looking for a RS485 port outlet, and 2x5-pin lines of pins.
Images from the PCB:
http://www.facebook.com/media/set/?set=a.1979958333026.114473.1065188491
IPSEC have read so far by launching tube through a communication
gateway through
which to get "home location register" information, etc..
Whether there is a chance to even download the firmware via the serial
terminal analysis?
Or perhaps to be found in lines of pins USB option?
The presentation referred to the serial port connection just yet to start
when you press the reset button four times, then the boot menu to configure
the IP address, login data.
greetings: bthomyka
Dear Developers!
Currently, the only tool I have found this information:
http://users.atw.hu/helvei/UAP3801E.rar?atw_referer=http% 3A% 2F% 2Fmobil-
telefon.vatera.hu 2Fmobiltelefon_tartozek%%% 2Fegyeb
2F4_db_huawei_ap_femtocella_mobil_bazisallomas_1459406466.html
This is a power point presentation, the pages visible to a certain set of
procedures.
Although I do not know how much help in the development, but I share with
you.
Consulted during a programmer who is interested in finding a "reverse
engineering" and curious about the possibility of the device, the
communication.
I am confident that if he succeeds, much of the project promotes the
development
of OpenBSC.
Regards,
bthomyka
On 05/30/2011 06:27 AM, Seungju Kim wrote:
> Hello, I am experiencing some crash with osmo-sgsn.
> This is the log : http://pastebin.com/XP8RcaaNI didnt make any modification except removing imsi roaming check.
> Every time when a phone tries to connect this happens. What might be wrong?
Hi,
please make yourself gdb and git and create a patch. The struct msgb has
detected a mis-use and forced a crash. What is going wrong is in the log, you
will need to identify where this msgb got allocated (or change the panic
message to print the name of the msgb) and see why it is using the amount of
headroom it wants to use.
happy hacking
holger
Dear OpenBSC users and developers!
I beseech you, help me with some information.
Today I bought a 4 pack auction Huawei femtocell UAP 3801. Next to them
there's no documentation, Huawei has not yet responded to my questions.
I want them to operate with OpenBSC. Do you think this tool will work with
it?
If anyone are having operating instructions, configuration instructions, please
share it with me.
Thanks,
bthomyka