Hi Nikos,
On Thu, Jul 21, 2022 at 03:32:26AM +0300, Nikos Balkanas wrote:
I am trying to develop a mobile loop (uplink) for the receiver in receiver_impl.cc.
Despite working in GSM related development for a long time, I'm not sure what a 'mobile loop (uplink)' is.
In any case, if you want to receive uplink signals you are building a BTS, and there is a robust, fully working (and production deployed) GSM BTS-side receiver in osmo-trx https://osmocom.org/projects/osmotrx/wiki/OsmoTRX
gr-gsm currently synchronizes, finds the start of a burst, using FCHH and SCHH signals. These are all downlink signals. There is no provision for synchronizing to uplink signals.
Yes. While I am not an author of gr-gsm, the entire point of the project was to implement the mobile station (MS) side, as for the BTS side there were long known and working implementations in both the OpenBTS, and later OsmoTRX/BTS and YateBTS projects.