Hi Max,

Multi-trx works properly with UmTRX which is our reference platform. We've also done partial testing with OpenCellular - spectrum analyser showed that TX is fine, but we haven't tested with a phone. With UmTRX we tested everything.

Since OpenCellular is a B210 derivative, it should work fine as well.

Could you try adding -x option to osmo-trx to enable external clock? If you have a spectrum analyser, I would recommend you to use it to test the signal and frequency offset of the signal.

On general, if everything starts and you don't see a network, it's most likely a clock or RF issue.

For -m option fail it would be great if you create a ticket and attach logs.

Please excuse typos. Written with a touchscreen keyboard.

--
Regards,
Alexander Chemeris
CTO/Founder Fairwaves, Inc.
https://fairwaves.co

On Mar 3, 2017 12:17 PM, "Max" <msuraev@sysmocom.de> wrote:
Hi.

There's been few updates to osmo-bts-trx recently so I've decided to get back to https://projects.osmocom.org/issues/1648 and it seems like it's completely broken:
- the "multiplexing" option (osmo-trx -m -c 2) which used to work now leads to startup error of osmo-trx
- the "separate channel" option (osmo-trx -c 2) which wasn't working properly but at least phone could see the network, now leads to situation where no network is visible

Am I missing some magic combination of .cfg and command-line parameters which could make it work? Am I using too old version of uhd or smth else?

The hw has not changed (usrp b210 + external 10MHz reference clock) but maybe I've got to do some calibrations on it?

Any ideas as to what could be causing those regressions?

Is there anyone out there for whom some multi-trx setup is working? If so, I'd like to compare notes to understand why it isn't working form me.

--
Max Suraev <msuraev@sysmocom.de> http://www.sysmocom.de/
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