A Modular O-RAN Testbed Based on SRS Open Source O-CU/O-DU and Massive Beams Modular O-RU
2026-07-06 • Networking and Internet Architecture
Networking and Internet Architecture
AI summaryⓘ
The authors introduce a flexible 5G network setup made of separate parts: a core, central and distributed units from Software Radio Systems, and a radio unit from Massive Beams. These parts work together following official 5G standards, allowing different ways to run and test the system. They also discuss adding an analog beamformer to improve signal handling. This setup is useful for researchers and industry to try out new 5G and future 6G ideas in a practical, easy-to-use way.
O-RAN5G CoreO-CUO-DUO-RUgNodeBsoftware-defined radiobeamformingPHY layersplit 7.2a
Authors
Fabian Göttsch, Oriol Font-Bach, Andreas Benzin, Dennis Osterland, Andre Puschmann, Felix-Christopher Lutz, Wilhelm Keusgen, Giuseppe Caire
Abstract
In this paper, we present a modular open radio access network (O-RAN) consisting of the 5G Core, a central (O-CU) and distributed unit (O-DU) by Software Radio Systems (SRS) and an O-RAN radio unit (O-RU), MODRAD-SC, by Massive Beams (MB). OCUDU provides an open source 5G-compliant O-CU and O-DU solution developed by SRS, while MB's radio unit is a fully O-RAN compliant category A O-RU. According to O-RAN split 7.2a, OCUDU performs higher layer functions up to the high physical (PHY) layer, while the O-RU handles low PHY and RF functions. This results in an O-RAN-compliant 5G gNodeB. In an alternative configuration, OCUDU and MODRAD-SC operate in a software-defined radio fashion corresponding to split 8, facilitating non-real-time experiments among others. In both cases, the system provides full control over O-CU, O-DU, and O-RU. In addition, we will discuss the possibility to attach an analog beamformer to the O-RU, enabling hybrid digital-analog beamforming. The flexibility and modularity offered by OCUDU and MODRAD-SC enable the practical realization of a multitude of applications, ranging from 5G demonstrators to pre-6G experiments. The system addresses the requirements of academia and industry and is well-suited as an easy-to-use platform for experimental and practical deployments.