物聯網(Internet of Things, IoT)的概念於近年蓬勃發展，其廣泛的應用範圍帶來龐大商機，如何穩定且可靠地獲取感測數據是建構IoT應用時的基礎工作，但在選用聯網通訊方法時常面臨下列困境：(一)使用有線通訊傳輸時，其可靠性及穩定性較強，但佈線不易，且聯網設備擺放位置受限；(二)使用無線通訊傳輸時，其傳輸距離及傳輸品質易受天氣、電磁波、障礙物等因素影響，可靠性不如有線通訊。故需要兼具佈線靈活性及傳輸可靠性之聯網架構，在不便使用有線通訊傳輸的IoT應用中，確保數據能夠穩定回傳不中斷。
因此本研究設計與實現多模雙向通訊智慧聯網架構，具智慧多模通訊機制、智慧中繼聯網機制與雙向互聯通訊機制，可在進行傳輸時智慧自動化切換使用4G、NB-IoT及LoRa無線通訊，解決使用單一通訊傳輸時訊號不穩或中斷的問題；亦可透過多跳無線網路(Multi-Hop Wireless Network, MWN)，讓資訊封包在終端節點與中繼節點間轉送，增長聯網架構傳輸距離；並可以在不向電信商租用固定IP服務的情況下，以較低成本實現上傳感測數據及下達控制命令的雙向傳輸功能。
本研究將多模雙向通訊智慧聯網架構導入二個應用案例中，證明本研究具可行性與實用性：(一)升級舊有的移動式泵浦機組，達到數據採集、遠端監控、數據可視化等功能，實現具創新管理與維保模式之移動式泵浦資訊管理監控系統；(二)使用工業總線與Modbus通訊協定讀寫資訊至工控設備，達到雙向數據傳輸與遠端控制功能，建構工控設備遠端資訊監控系統。
最後，本研究設計於具不同影響因子的實驗環境下進行傳輸性能測試，探討多模雙向通訊智慧聯網架構之傳輸性能與天氣、氣溫、部署地點及障礙物之間的關聯。實驗數據顯示，多模雙向通訊智慧聯網架構在大雨時便可減低6%封包遺失率，且可以在基地台訊號覆蓋範圍外額外增長半徑1公里以上的傳輸範圍。

Wired communications are characterized by high reliability and stability, but not easy wiring and limited placement of IoT devices. Wireless communication is characterized by high deployment flexibility, but transmission performance is easily affected by weather, electromagnetic waves, obstacles, and other factors.
To maintain the transmission advantages of the above two, and solve the problem of signal instability or interruption that often occurs when using single-mode communication transmission. The smart multi-mode networking architecture using NB-IoT and LoRa with bi-direction communication function is proposed in this study. Multi-mode Communication Nodes (MMCN) can intelligently and automatically switch to use different wireless communications (such as 4G, NB, or LoRa) according to the current environment for transmission. And it can also use Multi-Hop Wireless Network (MWN) to transfer data packets between end nodes and relay nodes, increasing the transmission distance of networking architecture.
Besides, to prove the feasibility and practicality of the smart multi-mode networking architecture, it was introduced into two application cases: (a) A portable pump information monitoring system with innovative management and maintenance mode; (b) A remote information monitoring system for industrial equipment.
Finally, MMCN were deployed in experimental environments with different impact factors to explore the relationship between the transmission performance of MMCN and weather conditions, temperature, deployment locations, and obstacles.
The results show that the packet loss rate can be reduced by 6% during heavy rain, and the radius of transmission range beyond the base station signal coverage can be increased by more than 1 km.

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