A few years ago a number of clever guys figured out how to access the layer 1 functionality of a certain type of modem chip built into entry level GSM phones and implement the GSM stack on a PC. I had a lot of fun getting that to work in a virtual machine and I learnt a lot in the process. Now a few guys have come up with something at least equally impressive: An open source implementation of an LTE eNB base station and an LTE UE.
According to the source code on Github the hardware required to run the layer 1 of the protocol stack is a USRP or bladeRF board. Everything else runs on a PC connected over USB. I haven’t tried this out myself yet as I don’t have the hardware for it and probably also not sufficient time to pull it off but it seems very impressive indeed!
So how far advanced is this? SRS, the Ireland based company behind the project, advertises a number of products built on this. Cool stuff, I would not have thought it’s possible to come up with a complete UE and eNB LTE protocol stack with just a few people and open source it on top.