Context-Aware Spectrum Coexistence of Terrestrial Beyond 5G Networks in Satellite Bands

TL;DR

The paper tackles the challenge of enabling terrestrial 5G in incumbent satellite bands without harming satellite receivers. It introduces CAT3S, a context-aware framework with a context-acquisition unit and a context-aware BS control unit, and formulates an NP-hard optimization problem $P_0$ that jointly selects active BSs, beams, and transmit powers to maximize downlink capacity while respecting an interference threshold $I_{th}$ and QoS constraints. A polynomial-time heuristic, Algorithm1, solves $P_0$ by iteratively optimizing beam and power decisions, leveraging context such as weather and antenna patterns. Evaluation in a realistic 12 GHz Blacksburg, VA scenario shows CAT3S achieves higher spectrum utilization and lower interference compared with baseline schemes, across sunny and rainy conditions and various FSS pointing angles, demonstrating the practical viability of context-aware spectrum sharing for upper mid-band satellite bands.

Abstract

Spectrum sharing between terrestrial 5G and incumbent networks in the satellite bands presents a promising avenue to satisfy the ever-increasing bandwidth demand of the next-generation wireless networks. However, protecting incumbent operations from harmful interference poses a fundamental challenge in accommodating terrestrial broadband cellular networks in the satellite bands. State-of-the-art spectrum-sharing policies usually consider several worst-case assumptions and ignore site-specific contextual factors in making spectrum-sharing decisions, and thus, often results in under-utilization of the shared band for the secondary licensees. To address such limitations, this paper introduces CAT3S (Context-Aware Terrestrial-Satellite Spectrum Sharing) framework that empowers the coexisting terrestrial 5G network to maximize utilization of the shared satellite band without creating harmful interference to the incumbent links by exploiting the contextual factors. CAT3S consists of the following two components: (i) context-acquisition unit to collect and process essential contextual information for spectrum sharing and (ii) context-aware base station (BS) control unit to optimize the set of operational BSs and their operation parameters (i.e., transmit power and active beams per sector). To evaluate the performance of the CAT3S, a realistic spectrum coexistence case study over the 12 GHz band is considered. Experiment results demonstrate that the proposed CAT3S achieves notably higher spectrum utilization than state-of-the-art spectrum-sharing policies in different weather contexts.

Figures (8)

• Figure 1: Overview of the proposed spectrum sharing scenario.
• Figure 2: Overview of CAT3S framework
• Figure 3: Aggregate I/N ratio vs FSS's pointing angles.
• Figure 4: Number of active BSs vs FSS's elevation angles.
• Figure 5: Achievable downlink capacity vs. FSS pointing angles.

Theorems & Definitions (2)

• Proposition 1
• Proposition 2