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：摘要：可靠的低时延通信是远程操作、自主导航及实时上行主导遥测等关键任务与移动自主系统的基本要求。尽管商用5G网络通常能提供充足的下行性能，但在农村部署场景中，上行性能可能受限于无线资源约束与上行功率控制机制。本文基于在城市、郊区及农村环境开展的测量活动，对商用5G非独立组网中的多连接策略进行了全面的实验评估。研究分析了跨两个移动网络运营商的逐包上行与下行时延、丢包率及无线层关键性能指标。测量结果表明，时延与可靠性无法仅通过RSRP等覆盖指标推断。在覆盖受限场景中，性能明显受上行功率受限运行模式及运营商间部分相关损伤的强烈影响。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。提出了一种主锚点自适应故障切换（PAAF）框架，可根据无线、时延及服务成本因素选择性地激活冗余机制。结果表明，在所评估的农村场景中，部分复制（PD）方法能在显著降低复制开销的同时达到接近多连接的可靠性水平。