OsmoBTS

OsmoBTS is a software part of a BTS, which implements Layer 1, Layer 2 and Layer 3:

• LAPDm (GSM 04.06)
• RTP
• A-bis/IP (similar to ip.access nanoBTS)
• OML (GSM 12.21)
• RSL (GSM 08.58)

OsmoBTS is building up on work done previosuly for OpenBSC (RSL, OML, RTP) and  OsmocomBB (LAPDm). A-bis/IP implementation is heavily inspired by ip.access nanoBTS A-bis/IP implementation.

OsmoBTS is written in a re-targettable way, i.e. it should be relatively easy to target a new BTS hardware (i.e. BTS-side Layer 0 or Layer 1) with it.

Hardware support

So far OsmoBTS supports a number of hardware options:

• Quad-band femto-BTS product called  sysmoBTS which is sold by  sysmocom
• Wideband SDR transceiver hardware  UmTRX sold by  fairwaves and a number of other SDR transceivers, using OpenBTS transceiver software.
• A pretty crazy experimental BTS hardware based on two OsmocomBB phones had originally been supported, but needs to be re-integrated with core code changes.

Check out network_from_scratch page for more information how to run OsmoBTS with UmTRX (using the OpenBTS transceiver software) or OsmocomBB phones.

Status

The source code includes a  http://cgit.osmocom.org/cgit/osmo-bts/tree/README file with current status information

GPRS support

osmo-bts has recently been extended with a socket interface towards osmo-pcu. This adds GPRS (and later EDGE) support to it.

Source code

The source code is available from git.osmocom.org (module osmo-bts).

Public read-only access is available via

git clone  git://git.osmocom.org/osmo-bts

You can browse it via cgit:  http://cgit.osmocom.org/cgit/osmo-bts/

Authors

OsmoBTS was developed mainly by Andreas Eversberg and Harald Welte.