Multichannel 2G osmobts with one LimeSDR


#1

Hello all!
I’m using LimeSDR mini with Osmo-bsc project.
By default this software uses 1 physical channel for transmitting 7 timeslots, like there is 1 physical base station transceiver.
I want to use more timeslots in one area. I see, that using more physical channels simultaneously can solve my problem. As we using SDRs, it is possible to transmit whatever in SDR’s bandwidth. So it shouldn’t be problem to implement multiple physical channels in one SDR bandwidth.
So, does anybody tried that? Does osmocom base station software allow to do that and the trick is just to change something in config files? Can anybody help?


#2

What you suggest sounds possible, provided that the channels fit within the SDR bandwidth. However, I’m not aware of such support in OsmoTRX, but the best place to ask would be the Osmocom list.


#3

Done, thank you Andrew for the help!


#4

Hi Armin,

regarding run of 2 separate TRX running on separate channels with LimeSDR(-usb?), it’s not working yet as far as I know, see https://osmocom.org/issues/3346

Regarding running 2-3 TRX mixed in the same same SDR channel: There’s some support for that in OsmoTRX, but works only on some devices on osmo-trx-uhd (like ettus B200 iirc), and with some restrictions regarding ARFCNs to be used (and lots of CPU power required). For more information, see https://ftp.osmocom.org/docs/latest/osmotrx-usermanual.pdf section “11.2 Multi-ARFCN mode”.

Feel free to ask or provide more information in osmocom mailing lists.