Hi,

I noticed that the OSMOGMR project is mainly about receiving and decoding downlink GMR data. Can I build my own GMR satellite/base station and core network based on open-source software (e.g. osmo-bts) and SDR? GMR is mentioned in the Osmo-bts user manual, but it doesn't say if it is implemented and how to configure it. If Osmo-bts doesn't work, is there any other project to build my own GMR base station and establish a connection with a GMR device?

Simply said : No.

The lower level ( SDR mod/demod and all the channel coding/decoding ) handles both RX and TX but there is currently no implementation whatsoever of the higher levels that would be required to act as a GMR "base station". One could use osmo-bts as a basis for such an implementation but it's not "plug and play", there is a significant amount of work required.

Cheers,

Sylvain