近年來無人機的蓬勃發展下，使用頻率劇增，這也使其資安問題逐漸浮上檯面。MAVLink(Micro Aerial Vehicle Link)，是目前被廣泛應用於地面控制站與無人機之間的通訊協議，但卻不會對傳輸內容做加密處理，這對於通訊系統的機密性是一大漏洞，且容易遭受到惡意攻擊。本研究以建立無人機通訊加密系統為目標，首先會利用ChaCha20、Salsa20與Rabbit三種對稱加密演算法，來建立加密演算法函數庫，將MAVLink通訊協議下的通訊資料進行加密處理。並將Ardupilot飛控韌體程式進行改寫、編譯與燒錄來建立無人機通訊加密系統，再透過實驗測試系統完整性和傳輸情況。
最後實驗測試結果，無人機通訊加密系統能夠在無人機執行飛行任務時，能有效的防止惡意人士的連接嘗試，並成功地將MAVLink資料包的資料內容進行加密處理，降低了MAVLink通訊協議的漏洞，增加了無人機系統的安全，此外無人機通訊加密系統中，Salsa20、Chacha20與Rabbit三種加密演算法的傳輸量表現相近，對於無人機通訊系統的傳輸量影響相對較小，且三種加密演算法都展現不錯的實用性。

In recent years, with the flourishing development of unmanned aerial vehicles (UAVs), their usage has significantly increased, bringing the issue of information security to the forefront. The MAVLink (Micro Aerial Vehicle Link) protocol is widely employed for communication between ground control stations and UAVs. However, it lacks encryption, posing a significant vulnerability in terms of communication confidentiality and making it susceptible to malicious attacks. This research aims to establish an unmanned aerial vehicle communication encryption system. It begins by creating a library of encryption algorithms, utilizing ChaCha20, Salsa20, and Rabbit symmetric encryption algorithms to encrypt the communication data under the MAVLink protocol. Subsequently, the Ardupilot flight control firmware is modified, compiled, and burned to create the unmanned aerial vehicle communication encryption system. Experimental testing is conducted to verify system integrity and transmission efficiency.
The experimental results demonstrate that the unmanned aerial vehicle communication encryption system effectively prevents unauthorized connection attempts during UAV flight missions. The MAVLink data is securely encrypted, mitigating vulnerabilities within the protocol and enhancing the overall security of the UAV system. Additionally, the performance of Salsa20, ChaCha20, and Rabbit encryption algorithms in the unmanned aerial vehicle communication encryption system is comparable, showing a minimal impact on transmission efficiency. All three encryption algorithms exhibit promising practicality.

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