E1-based BTS¶

OsmoBSC supports a number of E1-based BTS models in addition to IP-based OsmoBTS and nanoBTS. This mode of operation is probably not used very much these days, due to dwindling supply of legacy E1 BTS hardware, but I (falconia) hold the view that in certain aspects of TCH operation (particularly the path from TCH UL Rx to TRAU-UL frame output), some E1-based BTS should be used as a "golden reference" for most correct BTS operation, to be replicated in OsmoBTS. I am currently hoping to receive a donated Nokia InSite BTS, in which case I shall use that hardware for knowledge-gathering experiments documented on these wiki pages - however, I am also documenting everything I seek to test, so that these experiments can be performed by other community members with access to the necessary hardware.

Having an E1 BTS for development and testing will (of course) facilitate improvements to the quality of Osmocom support for such legacy BTS - but that support may not have much value if the hardware is rapidly becoming unobtainium. However, many of the experiments I have in mind are designed to extract knowledge that will be useful outside of E1 BTS support in itself: knowledge that will allow OsmoBTS to be made more correct in corner cases, and will be needed for correct and robust implementation of TFO.

• BFI criteria
• DTXu half-blocks
• HRv1 UL Rx
• InSite UL captures
• No-data output