POLARIS：PHY感知的动态频谱共享频谱引导

Jul 16, 2026

Dynamic Spectrum Sharing (DSS) makes it possible to activate additional radio spectrum resources, but it raises a runtime decision problem: how to steer connected UEs to newly available spectrum with minimal service disruption. The work provides a first PHY-aware characterization of 3GPP-compliant UE steering mechanisms, using modem-level traces from 1,600 executions over four months across 12 urban areas. By mapping mechanisms to PHY milestones, it separates PHY-centric latency from RRC-to-PHY completion. Results show strong heterogeneity across mechanisms and motivate POLARIS, an O-RAN-based disruption-aware selector.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages6

Reading Time15 min

Introduction

Related Work

POLARIS: PHY-Aware Spectrum Steering for Dynamic Spectrum Sharing arXiv :2604 .0 1087v2 [ cs .NI] 12 Jul 2026 Stavros Dimou Northeastern University Boston, MA, USA [dimou.s@northeastern.edu](dimou.s@northeastern.edu) Abstract—Dynamic Spectrum Sharing (DSS) enables flexible activation of additional spectrum resources but leaves open a key runtime question: once new spectrum becomes available, which steering mechanism should migrate connected devices toward it with minimum service disruption? We present the first PHY-aware characterization of 3GPP-compliant UE steering mechanisms, including Bandwidth Part (BWP) reconfiguration, Carrier Aggregation (CA), E-UTRA-NR Dual Connectivity (EN-DC), ConnectedMode Handover (HO), and Release and Redirection (R&R), using modem-level traces from devices connected to operational networks, collected across 1,600 executions over four months in 12 urban areas. By mapping each mechanism to observable PHYlayer milestones, we decompose steering latency into intrinsic PHY-centric execution and RRC-to-PHY completion components, revealing substantial heterogeneity: NR BWP achieves 6.25ms mean latency with zero tail exceedance above 50ms, while CA exceeds 1225ms; mobility procedures remain largely modem-bound, whereas discovery-driven mechanisms experience significant RRCto-PHY completion amplification. Guided by these measurements, we design POLARIS, an O-RAN-based system that selects the least disruptive steering mechanism via a two-parameter disruption score. POLARIS reduces mean latency by up to 85. 1% and T95 by 89.7% over static or non-adaptive baselines, eliminates tail exceedance above 50ms, and avoids high-disruption mechanisms, demonstrating that PHY-layer execution profiling enables reliable and context-aware spectrum steering in DSS-enabled networks. Index Terms—Spectrum Sharing, O-RAN, PHY-layer, 5G NR I. INTRODUCTION The rapid growth of mobile connectivity is placing increasing pressure on radio spectrum utilization. Industry forecasts project several billion 5G subscriptions within the coming decade [1], while spectrum (1–6 GHz) remains highly contested [2], and largely underutilized. To address this inefficiency, regulatory initiatives such as localized spectrum licensing [3] and the Citizens Broadband Radio Service (CBRS) framework [4] have introduced mechanisms that promote more flexible shared access to spectrum resources. While these frameworks enable Dynamic Spectrum Sharing (DSS), they leave two questions largely unexplored: once spectrum resources become available, how should User Equipments (UEs) be steered toward them efficiently, and what performance cost do the available steering mechanisms impose on the UE? 3GPP specifies multiple mechanisms that can steer connected UEs toward newly available spectrum, including Bandwidth Part (BWP) reconfiguration, Carrier Aggregation (CA) Secondary Cell (SCell) addition, E-UTRA–NR Dual Connectivity (EN-DC), Connected-Mode Handover (HO), and Release and Guevara Noubir Northeastern University Boston, MA, USA [g.noubir@northeastern.edu](g.noubir@northeastern.edu) Redirection (R&R) . However, these mechanisms were originally designed for mobility, connectivity expansion, or load balancing rather than DSS. Although their signaling procedures are well specified in prior work, their behavior during spectrum activation, particularly their impact on UE-side Physical Layer (PHY-layer), remains largely unexplored. As a result, a critical gap remains in understanding which steering mechanisms are most suitable for DSS and what UE-side disruption costs they introduce. This gap becomes particularly relevant in the context of Open Radio Access Network (O-RAN) architecture, which introducesa new level of network programmability. By disaggregating the RAN into modular components, O-RAN replaces monolithic deployments with an open architecture. Following principles similar to Software-Defined Networking (SDN), O-RAN supports netwo

FAQs

DSS中需要解决的关键运行时问题是什么？

当新的频谱资源可用时，需要决定用哪种引导机制将已连接的UE迁移到新频谱，同时尽量减少服务中断与性能损失。

本文如何评估不同3GPP UE引导机制对UE侧的影响？

通过从商用终端设备收集的调制解调器级跟踪数据，将引导过程映射到可观测的PHY层里程碑，并将引导时延拆分为PHY-centric执行与RRC到PHY完成两个部分。

POLARIS如何在O-RAN中选择最不具破坏性的引导机制？

POLARIS基于O-RAN，通过一个考虑“破坏度”的两参数评分来选择最少扰动的引导机制，从而在与静态或非自适应基线相比时显著降低平均时延与T95，并消除50ms以上尾部超限。

Jul 16, 2026

Upload by Olivia Brown