RANsemi Limited, the British semiconductor innovator pioneering Open RAN baseband System-on-Chip (SoC) platforms for 5G networks, and TechPhosis Private Limited, one of India’s leading 5G CU/DU stack solution providers and Open RAN integration specialists, have integrated the Linux Foundation’s open source 5G OCUDU CU/DU software stack with the RANsemi RNS802 baseband PHY using the Small Cell Forum (SCF) FAPI interface.
The work demonstrates that open source CU/DU software can be combined with an optimised commercial PHY via industry-standard interfaces, creating a practical path to low-SWaP (size, weight and power) 5G integrated small cell deployments. While OCUDU is often associated with O-RAN architectures (Split 7.x), the collaboration shows that the software can also apply to compact, integrated small cell systems.
Hosted by the Linux Foundation, OCUDU (Open Centralized Unit / Distributed Unit) is an open source CU/DU software platform designed for commercial deployment in 5G and future wireless networks. Unlike proprietary software platforms, open source software does not come with a vendor responsible for integration. Through its deep RAN L2/L3 and system integration expertise, TechPhosis bridges the gap between open source software and commercially deployable 5G infrastructure products.
“Open source software and standards-based interoperability are becoming increasingly important within wireless infrastructure. This cooperation with TechPhosis illustrates how open ecosystems and commercial wireless technology can work together to create greater flexibility and choice for future wireless infrastructure deployments,” said Peter Claydon, CEO of RANsemi.
Using an RNS802 development platform, OCUDU software was integrated with RANsemi’s optimised PHY software to create a complete 5G gNB architecture, validating the open source approach for integrated small cell deployments.
The work builds on the collaboration announced by RANsemi and TechPhosis in November 2025 to develop an Integrated Small Cell Starter Kit, extending the partnership’s focus on practical, deployable 5G infrastructure.
Beyond integrated small cells, the collaboration supports a software architecture that can span multiple deployment models. The same OCUDU-based approach can extend to O-RAN 7.2 architectures using the RANsemi RNS805 O-RU SoC, offering developers both integrated and disaggregated deployment options with a single, consistent software approach.
“Open source software provides an important foundation for innovation, but customers also require enhancements, integration and support. Our joint work with RANsemi shows how open source innovation can be translated into deployable 5G infrastructure, helping customers move from software availability to real-world networks,” said Mangal Singh, Co-Founder and COO of TechPhosis.
Applications include private networks, mission-critical communications and defence-related wireless infrastructure, where open source software, standards-based interoperability and flexibility can help simplify deployment and expand technology choices.
