Reliable low-latency communication is a key requirement for mission-critical and mobile autonomous systems, including teleoperation, autonomous navigation, and real-time uplink-dominant telemetry applications. While commercial 5G networks often provide adequate downlink performance, uplink performance in rural deployments may be constrained by radio-resource limitations and uplink power-control mechanisms. This paper presents a comprehensive experimental evaluation of multi-connectivity strategies over commercial 5G Non-Standalone networks, based on measurement campaigns conducted in urban, suburban, and rural environments. The study analyzes per-packet uplink and downlink latency, packet loss, and radio-layer KPIs across two mobile network operators. The measurements indicate that latency and reliability cannot be inferred solely from coverage indicators such as RSRP. In coverage-constrained scenarios, performance appears to be strongly influenced by uplink power-limited operation and partially correlated impairments across operators. Several multi-connectivity strategies are evaluated, including link aggregation, switching-based policies, and conditional packet duplication. A Primary-Anchored Adaptive Failover (PAAF) framework is introduced to selectively activate redundancy based on radio, latency and service cost considerations. The results suggest that Partial Duplication (PD) approaches can approach the reliability of multi-connectivity while substantially reducing duplication overhead in the evaluated rural scenario.

翻译：可靠低延迟通信是任务关键型及移动自主系统（包括远程操作、自主导航及实时上行主导遥测应用）的核心需求。尽管商用5G网络通常能提供充足的下行性能，但农村部署中的上行性能可能受限于无线资源限制和上行功率控制机制。本文基于在城市、郊区和农村环境中开展的测量活动，对商用5G非独立组网上的多连接策略进行了全面实验评估。研究分析了跨两个移动网络运营商的每包上行和下行延迟、丢包率及无线层关键性能指标。测量结果表明，延迟和可靠性无法仅从覆盖指标（如RSRP）推断。在覆盖受限场景中，性能显著受上行功率受限操作及运营商间部分相关损伤的影响。本文评估了多种多连接策略，包括链路聚合、基于切换的策略及条件性数据包复制。提出了一种主锚定自适应故障切换框架，该框架可根据无线、延迟及服务成本考量选择性激活冗余。结果表明，部分复制方法在评估的农村场景中可接近多连接的可靠性水平，同时显著降低复制开销。