使用信號到達角度(Angle of Arrival, AOA)估測技術的天線陣列可以有效地對射頻信號源進行定向。已有許多研究提出了不同的演算法來估測信號源之AOA資訊；本論文主要使用可同時對多信號源進行估測的多信號分類演算法(Multiple Signal Classification, MUSIC)進行信號源定向。
近年來無人機(Unmanned Aerial Vehicle, UAV)獲得了學術界的關注，並已應用在許多實務工程中。本論文使用無人機群／無人機陣列(UAV Array)裝備射頻接收器並利用信號到達角度估測技術對地面信號源進行被動式定位。
本論文之特色為利用無人機的機動性而使陣列的幾何佈置彈性化，可針對不同情境調整其陣列幾何佈置，進而提升其對信號源之定位效果。在本論文中，我們對無人機群幾何佈置進行研究與分析，並提出提升信號源定位精準度之優化無人機群佈置方法。
本論文使用MathWork的電腦數值模擬軟體MATLAB進行模型建置與效能分析，藉此驗證我們所提出之無人機群佈置方法。模擬結果表示，此方法能有效降低無人機群對信號源定位結果之誤差，進而提升最終定位精準度。

Antenna arrays using the Angle of Arrival (AOA) estimation technology can effectively locate RF signal sources. Many studies have proposed different algorithms to estimate the AOA information of the signal source. This paper mainly utilizes the Multiple Signal Classification (MUSIC) algorithm to estimate the AOA of the targets.
Recently, the unmanned aerial vehicle (UAV) technology has attracted the attention of the academia and has been applied in a wide range of practical projects. In this work, a UAV swarm, in which each UAV equipped with an RF receiver, is used to conduct passive positioning of signal sources on the ground using the AOA estimation technology.
The objective of this study is to utilize the maneuverability of the UAV to flexibly adjust the geometric configuration of the UAV swarm to improve its targeting accuracy of the signal sources. Hence, the geometric configuration of a UAV swarm is studied and analyzed; various configurations for positioning enhancement of a UAV swarm is explored in this work.
In this paper, MathWork's computer numerical simulation software MATLAB is used for modeling and performance analysis of the UAV swarm configurations. The simulation results show that the proposed configurations can effectively reduce the positioning errors of the terrestrial signal sources.

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