低功耗邊緣設備的系統實作與驗證

Abstract

本研究探討 IEEE 802.11ah（Wi-Fi HaLow）於物聯網（IoT）應用中的可行性與效能，並針對通訊穿透力、感測整合性與能耗管理等問題提出解決方案。系統以IEEE 802.11ah為核心，搭配 RS485 雷達水位感測器與 I2C 溫濕度感測器，實現異質感測資料之穩定蒐集與傳輸。實驗結果顯示，本系統具備良好通訊穩定性與低功耗特性，感測精度高且可於封閉環境中正常運作。資料透過 TimescaleDB 儲存並結合 Grafana 儀表板進行視覺化分析。本研究實驗測試邊緣端之裝置於啟動狀態、感測狀態及深度睡眠時期的工作電流與靜止電流，符合極低功耗運作標準。本實驗亦測試IEEE 802.11ah訊號的穩定性與強度，在室內的訊號強度(RSSI)平均約為-38.1dB，訊躁比(訊躁比)約落在33.6dB，而將其配合感測器放置於家用冰箱，測試封閉環境之下的訊號傳輸狀況，其訊號強度與訊躁比則分別為-59.4dB和9.3dB。證實 IEEE 802.11ah 於物聯網應用中之實務潛力，並為未來結合人工智慧與能源採集等智慧感測架構提供應用基礎。This study investigates the feasibility and performance of IEEE 802.11ah (Wi-Fi HaLow) in Internet of Things (IoT) applications, with a focus on communication penetration, sensor integration, and power management. The proposed system is based on IEEE 802.11ah and integrates RS485 radar water level sensors and I²C temperature-humidity sensors to achieve stable acquisition and transmission of heterogeneous sensing data. Experimental results demonstrate that the system features excellent communication stability and low power consumption, with high sensing accuracy and reliable operation even in enclosed environments. Data are stored in a TimescaleDB database and visualized via a Grafana dashboard for intuitive analysis. Power consumption measurements at the edge device show that both active and standby currents meet the standards for ultra-low-power operation. The system’s signal stability and strength were also evaluated: in indoor environments, the received signal strength indicator (RSSI) averaged around –38.1 dB, and the signal-to-noise ratio (SNR) reached approximately 33.6 dB. Further tests were conducted with the sensors placed inside a household refrigerator to assess performance in enclosed environments, where the RSSI and SNR were measured at –59.4 dB and 9.3 dB, respectively. These results confirm the practical potential of IEEE 802.11ah for IoT deployments and provide a foundation for future smart sensing frameworks integrating artificial intelligence and energy harvesting technologies.