Satellite-Terrestrial Spectrum Sharing in FR3 through QoS-Aware Power Control and Spatial Nulling

2026-03-23

AI Summary

This work addresses the challenge of severe interference arising from spectrum sharing between terrestrial 6G networks operating in the FR3 band (7.125–24.25 GHz) and non-terrestrial systems such as Starlink, which simultaneously offers favorable coverage and capacity characteristics for 6G. To mitigate this interference while preserving quality of service (QoS), the study proposes a novel joint optimization framework that systematically integrates QoS-aware power control with spatial interference nulling via beamforming. Through system-level simulations, the proposed approach demonstrates significant improvements in base station energy efficiency while effectively suppressing interference to satellite links, all without compromising terrestrial user QoS or fairness. The results provide a practical and viable solution for harmonious spectrum coexistence between ground-based and satellite communication systems in the FR3 band.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Search and Optimization: Distributed Search
• Constraint Satisfaction and Optimization: Distributed CSP/Optimization

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• Search and Retrieval-Augmented AI: Web evaluation methodologies and metrics
• User Modeling, Personalization and Recommendation: Federated recommendation systems and personalization

Abstract

Frequency Range 3 (FR3), encompassing frequencies between 7.125 and 24.25 GHz, is an emerging frequency band for 6th generation (6G) applications. The upper mid-band, as it is frequently referred to, represents the sweet spot between coverage and capacity, providing better range than mmWaves and higher bandwidth than the sub-6 GHz band. Despite these advantages, the spectrum is already occupied by incumbent systems such as satellites (e.g., Starlink), and sharing it with terrestrial cellular applications results in spectrum conflicts, only exacerbating the existing spectrum scarcity. This article investigates the impact of two state-of-the-art methods, namely Quality of Service (QoS)-Aware Power Control and Interference Nulling, as well as their joint application, on interference mitigation toward non-terrestrial links while maintaining acceptable QoS on terrestrial networks. Our simulation results demonstrate the advantages and disadvantages of each method, pinpointing how interference nulling can maintain high average performance and how power control is more appropriate for risk-averse scenarios to enhance fairness in terrestrial QoS. Finally, we showcase how the two can complement each other to enhance fairness in terrestrial QoS and increase the Next Generation Node Base (gNB)'s energy efficiency, while suppressing interference toward incumbents.

Problem

• spectrum sharing
• satellite-terrestrial interference
• FR3
• QoS
• incumbent systems

Innovation

• QoS-Aware Power Control
• Spatial Nulling
• Satellite-Terrestrial Spectrum Sharing
• FR3
• Interference Mitigation