🤖 AI Summary
This work addresses key challenges in the evolution of open and programmable radio access networks (O-RAN) for 5G/6G, including interoperability, acquisition of AI/ML training data, and validation in real-world environments. To this end, the authors integrate Colosseum—the world’s largest O-RAN digital twin platform—with X5G, a multi-vendor GPU-accelerated private 5G testbed, and propose CaST, an automated scenario generation methodology enabling high-fidelity digital twinning and end-to-end validation. By combining NVIDIA Aerial GPU-accelerated physical layer processing, the OpenAirInterface protocol stack, and a sub-millisecond control-loop dApp framework, the platform successfully supports the development and validation of intelligent RAN applications, including dynamic spectrum sharing, interference detection, network slicing, security mechanisms, and integrated sensing and communication.
📝 Abstract
The evolution of the Radio Access Network (RAN) in 5G and 6G technologies marks a shift toward open, programmable, and softwarized architectures, driven by the Open RAN paradigm. This approach emphasizes open interfaces for telemetry sharing, intelligent data-driven control loops for network optimization, and virtualization and disaggregation of multi-vendor RAN components. While promising, this transition introduces significant challenges, including the need to design interoperable solutions, acquire datasets to train and test AI/ML algorithms for inference and control, and develop testbeds to benchmark these solutions. Experimental wireless platforms and private 5G deployments play a key role, providing architectures comparable to real-world systems and enabling prototyping and testing in realistic environments. This dissertation focuses on the development and evaluation of complementary experimental platforms: Colosseum, the world's largest Open RAN digital twin, and X5G, an open, programmable, multi-vendor private 5G O-RAN testbed with GPU acceleration. The main contributions include: (i) CaST, enabling automated creation and validation of digital twin wireless scenarios through 3D modeling, ray-tracing, and channel sounding; (ii) validation of Colosseum digital twins at scale, demonstrating that emulated environments closely reproduce real-world setups; (iii) X5G, integrating NVIDIA Aerial GPU-accelerated PHY processing with OpenAirInterface higher layers; (iv) a GPU-accelerated dApp framework for real-time RAN inference, enabling sub-millisecond control loops for AI-native applications including ISAC; and (v) intelligent RAN applications spanning spectrum sharing, interference detection, network slicing, security, and CSI-based sensing. Overall, this dissertation provides an end-to-end methodology bridging digital and physical experimentation for next-generation cellular networks.