13 Apr
2011
13 Apr
'11
2:30 p.m.
On Wed, Apr 13, 2011 at 01:10:54PM +0200, Konrad Meier wrote:
Hi all,
I was just reading the wiki page about the nanoBTS multi-TRX setup.
Two things are not clear to me.
1. What is the purpose of the "RF cable"?
that is unclear, we don't have documentation on it..
The TIB (timing interface bus) cable is obvious: to synchronize timing.
The OML gets routed via the ethernet ports. So I don't really know why
they need an extra RF cable...
Is the TX port of the master BTS looped through the
second BTS? Or
hase every nanoBTS his own TRX/RX?
NO !!! my god, you don't want to kill your BTSs. Tx / Rx is separate
like before.
I am asking because I would like to use a
nanoBTS-Booster with the
multi-TRX setup and therefore require a combined RF signal.
the best idea is to use independent boosters. If you want to run two
TRX nanoBTS throguh one amplifier, you need high-grade RF combiner, make
sure the amplifier doesn't produce intermodulation, etc. Definitely not
something you want to be doing without somebody who has a clue about proper
RF setups at those frequencies.
2. The example example "openbsc.cfg"
configures the trx 1 as follows:
timeslot 0
phys_chan_config CCCH+SDCCH4
timeslot 1
phys_chan_config SDCCH8
Is this really needed? My first idea was to configure the second trx
to TCH/F only.
That depends on your network requirements, you can of course have all TCH/F.
--
- Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/
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