ASCENT: A Context-Aware Spectrum Coexistence Design and Implementation Toolset for Policymakers in Satellite Bands

TL;DR

The paper tackles the challenge of coexisting terrestrial 5G and licensed satellite incumbents in the upper mid-band (notably the 12.2-12.7 GHz range) where fixed policies are insufficient under varying weather and urban contexts. It introduces ASCENT, a modular, open-source toolset that combines a context broker, a dynamic spectrum access framework, a context-aware prioritization framework, an interference evaluation tool, and a policy engine to create a closed-loop policy testing environment. A Blacksburg, VA case study demonstrates that context-aware adjustments to exclusion zones (EZs) can maintain incumbent protection (with thresholds such as $-8.5$ dB in sunny and $-12$ dB in rainy conditions) while enabling greater secondary access. Key contributions include weather- and context-aware propagation modeling, a programmable policy interface for regulator testing, and a scalable, microservices-based implementation that supports rapid policy experimentation and validation. The work has practical impact by enabling regulators and researchers to design and test adaptive spectrum-sharing policies using realistic interference simulations that account for dynamic environmental factors.

Abstract

This paper introduces ASCENT (context Aware Spectrum Coexistence Design and Implementation) toolset, an advanced context-aware terrestrial satellite spectrum sharing toolset designed for researchers, policymakers, and regulators. It serves two essential purposes (a) evaluating the potential for harmful interference to primary users in satellite bands and (b) facilitating the analysis, design, and implementation of diverse regulatory policies on spectrum usage and sharing. Notably, ASCENT implements a closed-loop feedback system that allows dynamic adaptation of policies according to a wide range of contextual factors (e.g., weather, buildings, summer/winter foliage, etc.) and feedback on the impact of these policies through realistic simulation. Specifically, ASCENT comprises the following components (i) interference evaluation tool for evaluating interference at the incumbents in a spectrum-sharing environment while taking the underlying contexts, (ii) dynamic spectrum access (DSA) framework for providing context-aware instructions to adapt networking parameters and control secondary terrestrial network's access to the shared spectrum band according to context aware prioritization, (iii) Context broker to acquire essential and relevant contexts from external context information providers; and (iv) DSA Database to store dynamic and static contexts and the regulator's policy information. The closed-loop feedback system of ASCENT is implemented by integrating these components in a modular software architecture. A case study of sharing the lower 12 GHz Ku band (12.2-12.7 GHz) with the 5G terrestrial cellular network is considered, and the usability of ASCENT is demonstrated by dynamically changing exclusion zone's radius in different weather conditions.

Figures (6)

• Figure 1: Overview of ASCENT: Components and information flow.
• Figure 2: ASCENT GUI.
• Figure 3: Interference Analysis of Individual Base Stations for Sunny Weather
• Figure 4: Number of Active Base Station vs Exclusion Zone's Radii
• Figure 5: Interference Analysis of Individual Base Stations for Rainy Weather