New cellular software stack and base station design.

A new cellular software stack configuration has been published, which is much more feature rich and provides support for VoLTE and SMS, along with a new design for base station hardware.

PyHSS, Open5GS and Kamailio IMS

Deployment tooling, container images and configuration have been published for a new “standard” software installation which uses PyHSS for HSS and PCRF, Open5GS for all other EPC functions, and Kamailio for IMS to provide Voice-Over-LTE (VoLTE) and SMS services. The stack is based heavily on the excellent docker_open5gs project from Supreeth Herle, with numerous changes which aim to make it easier to set up a secure production LTE EPC and IMS using the stack. Such as:

  • Updating to current Ubuntu LTS for container images
  • Updating other software versions
  • Using upstream images for dependencies, e.g. MySQL and Redis
  • Switching from using environment variables to config files
  • Using a single HSS for EPC and IMS (PyHSS) instead of one for each
  • Using Ansible for deployment

While docker_open5gs remains the fastest way to stand up a lab environment for 4G or 5G, with OTA or simulated RF and various other options, the focus here will be squarely on 4G deployments with one particular architecture and features to support production use.

For further details, see Standard Software Installation.

CSRAN1 Design

The bill of materials, mechanical design and documentation has been published for a new reference cell site base station design, CRSAN1. This integrates a host computer for baseband processing, SDR, the LibreCellular RFE and two Band 3 Medium Power RF PAs, plus two cavity duplexers.

For further details see the LibreCellular documentation.

Next Steps

The next step for the software stack will be to develop a collection of Ansible roles which take care of generating configuration files for HSS, EPC and IMS etc. This will make it trivial to deploy a complete software stack configuration with custom network parameters.

Meanwhile on the hardware front we will be completing assembly, testing and characterisation of the first CSRAN1 system, and implementing software control for the RFE and PA modules.

With thanks to the developers of PyHSS, Open5GS, Kamailio and of course srsRAN 4G. A special thanks also to Supreeth Herle for the docker_open5gs project and his support.

The LibreCellular RFE has been developed as a collaboration between AB Open and Ordinatra Minima, and was funded through the NGI0 Entrust fund, established by NLnet with financial support from the European Commission’s Next Generation Internet programme, under the aegis of DG Communications Networks, Content and Technology under grant agreement No 101069594.