臺灣博碩士論文加值系統

物聯網是現代的一個趨勢，不管是用在農業、海洋甚至是普通的民生上都可
以看到的蹤跡。物聯網終端裝置通常會放在離使用者有段距離的地方，或是較為複雜的環境樹林或是海洋，因此物聯網的終端裝置通常不使用有線網路作連接而是使用無線網路。無線通訊有許多不同種類，常見的WiFi雖然傳輸速度快但是距離太短且所需消耗的能量成本也過高，不適用於遠距離的情況。因此本論文使用的是屬於廣域低功耗網路(LPWAN)技術中的LoRa，其有效的傳輸距離可達5-10KM甚至更遠，相當適合應用於遠距離傳輸。儘管如此，在遠距離或是複雜的環境中依然會有一些問題的發生，如因傳輸距離過遠、傳輸死角等造成封包遺失等問題。因此在本篇論文提出於現有LoRa物聯網環境中加入Relay Node的方式達到穿透死角與延長距離，同時針對Relay Node的加入引發系統節點間的封包碰撞問題深入探討並提出解決方法，並將這套系統應用於實際環境中做模擬實驗，以驗證系統的可行性。

Internet of Things (IoT) is not only a hot research topic but also becomes an
enabling technology for many new internet service paradigms. IoT technologies have
been widely used in agriculture, oceans or even ordinary people's livelihood. Most IoT access networks are based on wireless communications. There are many different types of wireless communication, such as WiFi or Bluetooth. While WiFi can provide high data rate, the effective communication distance covered by a WiFi device is quite limited. Moreover, energy consumption of WiFi devices is relatively high. In this thesis study, we use LoRa, a low-power wide-area network (LPWAN) technology, as the IoT access network. While the communication range of LoRa can reach 5-10 KM or even further in line-of-sight (LoS) transmission, we proposeto introduce relay nodes in the LoRa access network to sustain high packet transmission quality between the sensor nodes and the gateway nodes in the LoRa access network. In this thesis study we
investigate the packet collision problems caused by the introduction of the relay nodes to the access network and possible solutions to the problems as well. We design and
implement a small prototype system to validate our proposed scheme.

摘要 i
Abstract ii
目次 iii
圖次 v
表次 viii
第一章 緒論 1
1.1 研究動機 1
1.2 研究方法 2
1.3 論文架構 2
第二章 文獻探討及實驗器具 4
2.1 文獻探討 4
2.2 實驗器具 5
2.2.1 Arduino Uno 5
2.2.2 Raspberry Pi 3 B 6
2.2.3 LoRa Shield for Arduino 7
2.2.4 LoRa Shield for Raspberry Pi 8
2.2.6 MobaXterm 10
第三章 系統架構 11
3.1 系統架構 11
3.2 前端架構 12
3.1 後端架構 12
第四章 LoRa Relay傳輸碰撞問題與解決方案 14
4.1 問題探討 14
4.1.1 問題:封包碰撞 14
4.1.2 解決方法 15
4.1.3 延遲時間產生機制 17
4.2 Relay封包碰撞預防機制觀察實驗設計 18
4.2.1 各裝置內部動作設計 19
4.2.2 實驗的封包格式 22
4.3 封包傳輸時間量測準確度驗證 23
4.3.1 實驗規劃 23
4.3.2 實驗參數與環境 24
4.3.3 實驗步驟 25
4.3.4 實驗結果 26
4.4 Relay封包碰撞預防機制觀察實驗設計 27
4.4.1 LoRa Sensor Data傳送: 情境 1 27
4.4.2 LoRa Sensor Data傳送: 情境 2 31
4.4.3 LoRa Sensor Data傳送: 情境 3 36
4.4.4 LoRa Sensor Data傳送: 情境 4 40
4.4.5 LoRa Sensor Data傳送: 情境 5 46
4.4.6 LoRa Sensor Data傳送: 情境 6 51
4.4.7 LoRa Sensor Data傳送: 情境 9 (非對稱性傳輸) 57
第五章 前後端整合與實務 61
5.1 系統實作 61
5.1.1 前端 61
5.1.2 中間端 68
5.1.3 後端 74
5.2 系統應用情境模擬 83
第六章 結論與未來展望 86
6.1 結論 86
6.2 未來展望 86

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[12] 採用 LoRa® 技術的 Arduino Shield : https://www.dragino.com/products/lora/item/102-lora-shield.html
[13] 100cm長度 / 1米防水探針型熱電偶溫度感測器 不銹鋼封裝 防水型 DS18b20溫度感測器: https://www.taiwaniot.com.tw/product/