世界各地因人力短缺問題，已逐漸步入物聯網設備日漸增長且逐漸普遍
化的時代。尤其在現代農業中，為了應對這一嚴重問題，大家更期待著革
命性的自動化及智慧化農業科技，並且我們也可以看到許多智慧化、自動
化的科技也因此而誕生。借助基於 LoRaP2P+ 構建的灌溉系統，我們實現
了自動化的大規模灌溉，這其中幾乎無需人力參與。但對於大多數作物而
言，作物的產量與作物用水量有著直接相關的關係。由此可見在現代農業
中，可靠及精準地執行澆水動作來達到精確灌溉是至關重要的，也正因此，
所研發的自動化系統需要做到指令執行的確保才能在精準農業中發揮其效
用。本文所研發加強基於 LoRaPP+ 的可靠自動化灌溉系統可確保大面積精
準灌溉的執行，並在減輕農民負擔方面發揮著關鍵性的作用。
此外，端點設備的設備韌體更新在維護系統的可靠性和安全性方面發揮
著重要作用。對於通常部署在農村地區並使用 LoRa 作為長距離通訊的系
統，無線固件更新 (FUOTA) 功能提供了可為這些設備推出系統更新的可能
性，而這期間無需與設備進行物理接觸，卻可以確保所有設備是採用最新
的韌體固件。
在本論文中，我們增強了之前基於 LoRaP2P+ 構建的灌溉系統的可靠
性，並基於 LoRaP2P+ 開發了 FUOTA 功能。憑藉較低的延遲和可靠傳輸的
優勢，自動化系統可以對使用的農民起到更大的幫助。通過 FUOTA，更新
補丁也可以輕鬆且高效地部署到各個設備上，進一步減少人力短缺問題的
出現，同時更進一步地改進系統的特性和功能。

The increment of IoT devices in the world due to the manpower shortage can be commonly seen around the world nowadays. In agriculture, revolutionary technologies which involve automation has been anticipated in order to face this serious issue. With the irrigation system that we built based on LoRaP2P+, we achieved automated mass irrigation almost without the need for manpower involvement. For most crops, production and yield are directly related to crop water use, hence resulting in the importance of precise watering. Thus, our system's reliability plays a critical role to ensure watering precision to ease the farmers' burdens.
In addition, device firmware updates for the endpoint devices play an important role to maintain the reliability and security of a system. For a system that is using LoRa, which is commonly deployed in rural areas, the firmware update over the air(FUOTA) feature can provide the possibility of rolling out a system update without the need to have physical contact with the device while also ensuring all the devices are up-to-date.
In this thesis, we enhanced the reliability of a previously built irrigation which is based on LoRaP2P+ and developed the FUOTA feature for LoRaP2P+. With the advantages of lower latency and promising transmissions, the automated system can be more helpful to farmers. Through FUOTA, the update patches can also be deployed to the devices effortlessly and efficiently further reducing the manpower shortage problem while improving the feature and functionality of the system.

Acknowledgements
Abstract i
摘要 ii
1 Introduction 1
2 Related Work 5
2.1 LoW-Power Wide-Area-Network(LPWAN) 5
2.2 LoRa 7
2.3 LoRaWAN 8
2.4 LoRaP2P 10
2.4.1 LoRaP2P network architecture 10
2.4.2 LoRaP2P uplink modes 12
2.4.3 LoRaP2P channel activity detection 13
2.4.4 LoRaP2P message packet structure 14
2.5 LoRaP2P+ 15
2.6 Firmware Update Over the Air (FUOTA) 16
2.7 LoRaWAN FUOTA 17
2.8 Comparison to Previous Works 17
3 System Design and Implementation: Increased reliability 18
3.1 Gateway and Node architecture 18
3.2 Control system structure 21
3.3 Improving system function 22
3.3.1 Soft coding 24
3.3.2 Gateway alive polling mechanism 25
3.3.3 ESP32 watchdog timer 26
3.3.4 Gateway buffering mechanism 27
3.3.5 Beacon ensuring mechanism 28
3.3.6 Downlink priority setting 29
3.3.7 Ack and power status reporting 30
3.4 Report and monitoring system 31
3.4.1 Watering report 31
3.4.2 Alert report 31
3.5 Automated system testing simulator 33
4 Firmware Update Over the Air (FUOTA) 35
4.1 Motivation 35
4.2 Theory 35
4.3 System Architecture 36
4.4 FUOTA Flow 37
4.4.1 Firmware saving software design 40
4.4.2 Firmware update software design 43
4.4.3 Authentication 45
4.4.4 Packet structure 46
4.4.5 Go back N mechanism 47
4.4.6 Disruption tolerant retransmission 48
4.4.7 Reduce congestion mechanism 49
4.5 Recovery 50
5 Experiment and Results 52
5.1 Increased reliability 52
5.1.1 Experiment setup 52
5.1.2 Fix environment experiment result 55
5.1.3 Actual field result 56
5.2 FUOTA 59
5.2.1 Experiment Setup 59
5.2.2 FUOTA 1 node test experiment 62
5.2.3 FUOTA 2 nodes test experiment 63
5.2.4 FUOTA 12 nodes scalability experiment 64
5.2.5 FUOTA 12 nodes long distance experiment 65
5.2.6 Result analysis 66
6 Conclusions and Future Work 68
References 70

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