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.
- 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.
- 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.