This paper studies a ground-segment implementation problem in 5G non-terrestrial networks (NTN): once UE-side geometric pre-compensation has produced a coarse timing/frequency prior, can an edge-side residual loop keep the uplink inside an NR-feasible operating region under rapid LEO dynamics? We examine this question with a software-defined ground station (SDGS) design that keeps the coarse prior at the UE and closes the residual timing-advance (TA) / carrier-frequency-offset (CFO) loop at the ground-station edge. This paper takes a systems-and-control view rather than proposing a full-stack intelligent architecture. Its evidence base consists of a March 2026 hardware-in-the-loop (HIL) campaign and a companion uncertainty analysis. The HIL campaign includes same-window reference runs collected on the same platform with edge residual control disabled, but it does not include a cloud-loop benchmark. The placement claim is therefore architectural and control-oriented rather than a head-to-head cloud-versus-edge proof. In the Shenzhen steady-state tracking interval, the edge-controlled mode lowers mean RTT from 70.51 +/- 2.34 ms to 32.84 +/- 2.56 ms and, within the retained Layer-3 transport mapping, improves artifact-level goodput from 80.14 +/- 0.14 Mbps to 196.04 +/- 1.87 Mbps relative to that reference configuration. Across four ground-station locations, the closed-loop controller keeps residual TA P95 at 0.49 us and residual CFO P95 within 76-77 Hz. Together with the uncertainty analysis, these observations support a bounded claim: an edge-side residual timing/frequency loop can keep the SDGS uplink in a more stable NR-feasible operating regime under the assumptions retained in the current HIL artifact.

翻译：本文研究5G非地面网络（NTN）中的地面段实现问题：在用户端几何预补偿已提供粗定时/频率先验信息的条件下，边缘侧残留闭环能否在高速LEO动力学环境下维持上行链路在NR可行工作区域内？我们通过软件定义地面站（SDGS）设计来探讨该问题，该设计将粗先验信息保留在用户端，并在地面站边缘侧闭合残留定时提前（TA）/载波频率偏移（CFO）闭环。本文采取系统与控制视角而非提出全栈智能架构，其证据基础包含2026年3月的硬件在环（HIL）实验及配套的不确定性分析。HIL实验包含同平台禁用边缘残留控制状态的参考对照运行组（同窗口采集），但未包含云端闭环基准测试。因此，定位主张属于架构性与控制导向性的，而非"云端vs边缘"的正面比较证明。在深圳稳态跟踪区间内，相较于参考配置，边缘控制模式将平均RTT从70.51±2.34毫秒降至32.84±2.56毫秒，并在保留的三层传输映射条件下，将人工制品级吞吐量从80.14±0.14Mbps提升至196.04±1.87Mbps。在四个地面站位置测试中，闭环控制器将残留TA的P95控制在0.49微秒，残留CFO的P95保持在76-77Hz范围内。结合不确定性分析，这些观测结果支持有界性结论：在当前HIL人工制品保留的假设条件下，边缘侧残留定时/频率环可将SDGS上行链路维持在更稳定的NR可行工作区域内。