Functional Splits in Cloud-Based Radio Access Networks
Summary
Cloud-based Radio Access Networks (Cloud-RANs) represent a paradigm shift in mobile communications, decoupling traditional base station functions into centralised and distributed units. Functional splits define where processing tasks move between these units, offering operators flexibility to optimise latency, bandwidth and energy consumption across the fronthaul link. Lower-layer splits place more signal processing at the central unit, reducing remote hardware complexity but imposing stringent transport requirements. Higher-layer splits shift control-plane functions toward the distributed unit, easing fronthaul demands at the cost of increased site complexity. The choice of split option influences network performance in diverse deployment scenarios, from dense urban microcells to rural macrocells. Advances in virtualisation, software-defined radio and orchestration frameworks enable dynamic reconfiguration of splits in response to traffic patterns, service-level agreements and energy-efficiency targets. This adaptability underpins emerging architectures such as O-RAN, which standardise open interfaces for interoperable components. Global operators view functional splits as key enablers of flexible 5G and beyond-5G networks, supporting use cases from ultra-low-latency industrial automation to energy-conscious massive IoT. By orchestrating centralised resources and edge-level intelligence, Cloud-RANs promise to sustain exponential growth in mobile data while controlling operational costs and carbon footprint.
Research from Nature Portfolio
No recent Nature Portfolio content available.
Functional Splits in Cloud-Based Radio Access Networks publication trend
The graph below shows the total number of articles in functional splits in cloud-based radio access networks across all publications each year (not limited to Nature Index journals).
Technical terms
Cloud-RAN: A mobile-network architecture that centralises baseband processing in cloud data centres, connecting distributed radio heads via fronthaul links.
Fronthaul: The transport network segment carrying data between centralised units and distributed radio units, with strict latency and bandwidth requirements.
Functional split: The partitioning of RAN functions into centralised and distributed units, defined at various protocol layers to balance processing and transport load.
Central Unit (CU): The cloud-hosted element responsible for centralised baseband processing, higher-layer protocols and network orchestration.
Distributed Unit (DU): The on-site radio element handling lower-layer radio-frequency processing, real-time scheduling and local traffic management.
O-RAN: An open RAN initiative that standardises interfaces and promotes multi-vendor interoperability for cloud-based RAN deployments.
References
- Constrained Deep Reinforcement Based Functional Split Optimization in Virtualized RANs. IEEE Transactions on Wireless Communications (2022).
- Design of Wireless Fronthaul With mmWave LOS-MIMO and Sample-Level Coding for O-RAN and Beyond 5G Systems. IEEE Open Journal of the Communications Society (2023).
- FlexDRAN: Flexible Centralization in Disaggregated Radio Access Networks. IEEE Access (2022).
About these summaries
This Nature Research Intelligence Topic summary is created with the cited references and a large language model. We take care to ground generated text with facts, and have systems in place to gain human feedback on the overall quality of the process in line with our AI principles. We strive to create accurate and useful summaries for people unfamiliar with the research topic and that supports this goal. These pages are a beta release and will be updated as we learn how best to help people gain value from a research topic summary.
Turn complex research questions into confident strategic decisions
When you're under pressure to set direction, justify investment, or understand your competitive position, you need more than raw data — you need trusted insights you can act on.
Benchmark your performance against global peers using robust, methodologically sound analysis.
Combine quantitative metrics with qualitative expert insight to uncover strengths, gaps and emerging opportunities.
Gain tailored, decision-ready recommendations aligned to your strategic priorities.
Talk to us to learn more about our data dashboards and bespoke strategy reports.
Grow research skills, confidence and careers with training built for every stage of the research lifecycle.
Developed with Nature Portfolio journal Editors and internationally renowned experts. Discover three ways to learn:
Self-paced, online courses in convenient bite-sized units, covering key skills across scientific writing, publishing, grant writing, data analysis, and more.
Expert trainer-led workshops with hands-on exercises and real-time feedback across core research skills, delivered via interactive group sessions.
Editor-led workshops combining core principles in writing and publishing, personalised 1:1 feedback from Nature Portfolio Editors and hands-on exercises.
Explore course catalogues and workshop agendas, enquire about the options or request institutional pricing.