Towards Energy- and QoS-aware Load Balancing for 6G: Leveraging O-RAN to Achieve Sustainable and Energy-Efficient 6G

TL;DR

The paper addresses rising energy consumption in 6G mobile networks and proposes an adaptive energy- and QoS-aware load-balancing framework built on O-RAN. It formulates a MILP with objective $\min \sum_{t\in\mathcal{T}}\sum_{r_j\in\mathcal{R}} \frac{w^{t}_{r_j}}{\eta_{r_j}} + \theta^{RF}_{r_j}$ and constraints including $\sum_{r_j\in\mathcal{R}} x^{t}_{u_i,r_j} = 1$, $0 \le w^{t}_{r_j} \le \gamma_{r_j}$, $w^{t}_{r_j} \le z^{t}_{r_j} \gamma_{r_j}$, and a Shannon-bound $\sum_{r_j} y^{t}_{u_i,r_j} \log\left(1 + \frac{S}{N}\right) \ge \gamma_{u_i}^t$ with $\frac{S}{N} = \frac{\beta(u_i,r_j) w^{t}_{r_j}}{\sigma^2}$. The optimization is implemented via O-RAN-compliant rApps and xApps across Non-RT RIC and Near-RT RIC, validated in a realistic O-RAN prototype, and shown to deliver notable energy savings while maintaining QoS. The work contributes a practical architectural blueprint for integrating energy-saving control loops into 6G RANs, supplemented by extensive experimental evaluation and targeted component enhancements. Overall, the approach demonstrates a viable path to sustainable and energy-efficient 6G deployments leveraging the programmability and intelligence of O-RAN.

Abstract

This paper addresses the critical challenge posed by the increasing energy consumption in mobile networks, particularly with the advent of Sixth Generation (6G) technologies. We propose an adaptive network management framework that leverages the Open Radio Access Network (O-RAN) architecture to enhance network adaptability and energy efficiency. By utilizing O-RAN's open interfaces and intelligent controllers, our approach implements dynamic resource management strategies that respond to fluctuating user demands while maintaining the quality of service. We design and implement O-RAN-compliant applications to validate our framework, demonstrating significant improvements in energy efficiency without compromising network performance. Our study offers a comprehensive guide for utilizing O-RAN's open architecture to achieve sustainable and energy-efficient 6G networks, aligning with global efforts to reduce the environmental impact of mobile communication systems.

Figures (10)

• Figure 1: Prototype high-level architecture aligned with O-RAN.
• Figure 2: Interfaces of Near-RT RIC and xApp.
• Figure 3: Interfaces of Non-RT RIC and rApp.
• Figure 4: Exposure of SMO and Non-RT RIC framework services.
• Figure 5: Architecture of the proposed energy-saving O-RAN framework.