Hi Harald,
On 16.07.2011 15:51, Harald Welte wrote:
We have two
nanoBTS-Booster 1800 here at the university. If for some
reason the Ericsson RBS is not working it should be possible to lend
you the two bossters for the time of the camp. We also have a
splitter and combiner. I will test the splitter/combiner in
combination with a booster at the GPN end of this month.
As it turns out, I have not yet managed to get the Motorola BTSs
working, despite putting lots of time into it. There are many reasons,
but basically the Motorola BSS is _extremely_ different from normal GSM BSS
So while I might still get it to work, I doubt it, and it would be
better to pursue different plans now.
We can certainly bring together a sufficient number of nanoBTS units to
fill all our ARFCN. The problem now is the coverage<-> capacity
problem, i.e. I don't want 6 BTSs with small coverage area, but rather
something like 2 or 3 sites (max) with each 2 or 3 BTSs.
Have you meanwhile tested your splitter/combiner/booster setup? does it
work?
The original plan was to test the setup at the GPN. But stupid me forgot
to order the RJ69 connectors :-(
Last week I was finally able to try the multi TRX setup with two
nanoBTS, but without success. TRX 0 worked well but TRX 1 was not
working for some reason. I think the problem is the initialization of
TRX 1.
The nanoBTS are pretty new:
Equipment_Version='165g029_73' Software_Version='168a352_v142b30d0'
Unfortunately I didn't had the time to investigate the issue further.
Maybe tomorrow I have some time.
What I can really easily re-use from the Motorola BTS
are 2x hybrid
combiner/duplexer units, i.e. something that has the following ports:
* 1 antenna output, bidirectional, 7/16" socket
* 2 PA Tx inputs, SMA
* 1 Rx antenna output, N-type
So if you don't have a similar setup, we could use those together with
two nanoBTS with a Rx LNA and a Rx splitter.
I have six of those hybrid combiner/duplexers.
I have two "SPLIT2P-SMA" from "Global Professional" [1]. My Idea was
to
use these two units with one naoBTS-Booster like shown here: [2]
Your idea sounds good too, but would require some RX LNA.
I _might_ also get the Rx LNA + splitter of the
Motorola BTSs to work,
but those are less stand-alone and I'm not certain about it.
What do you have in terms of antennas?
We have two omnidirectional antennas from PROCOM: CXL 1800-3
More information: [3]
Also, when would you be able to provide the equipment
to me? I would
want to put everything together + test it well ahead of the camp,
probably around August 1st.
Ok, I will see what I can do.
Best regards
Konrad Meier
[1]
http://www.globalprofessional.co.uk/acatalog/Splitter_mod.html
[2]
http://lab.ks.uni-freiburg.de/attachments/download/260/setup.png
[3]
http://www.procom.dk/eng/Page_menu/Products/Base_Station_Antennas/1.3_-_2.0…