在信號來向角(Direction Of Arrival, DOA)估測研究中，相位干涉儀(Phase Interferometer)為一種高解析度的來向角估測演算法，干涉儀在基線(Baseline)較長時擁有較好的估測精準度，但當基線長度大於信號半波長時會發生相位模糊(Ambiguity)的問題，使量測相位差偏離實際相位差，導致估測角度結果錯誤。我們考慮將多支天線安裝在多架無人機(Unmanned Aerial Vehicle ,UAV)上使其形成無人機陣列，並利用相位干涉儀演算法將兩子群陣列對地面目標進行定位，進而分析影響相位干涉儀估測精準度的因素，並利用向量子空間(Vector Subspace)演算法，解決相位干涉儀在基線大於半波長時所產生之相位模糊的問題。透過我們所提出的方法，陣列間不再需要使用小於半波長之基線解決相位模糊，而可以直接使用大於半波長之基線進行估測，並探討多天線干涉儀時對地面目標物最適合的估測方式。

In the estimation of direction of arrival (DOA), the phase interferometer is a high-resolution algorithm for estimating the direction of arrival of signals. The estimation accuracy of interferometer improves when as the baseline is lengthened, but when the baseline is greater than the half-wavelength of the signal, the Ambiguity problem will occur, which makes the estimated phase difference no longer accurate.
In the thesis we consider the problem that arises when the antenna is mounted on an unmanned aerial vehicle (UAV) to form an array, which is divided into two groups to locate the ground target, and a multiple antenna interferometer array is formed. We use the vector subspace algorithm to solve the problem of phase interferometer on the long baseline. Therefore, it is no longer necessary to use a baseline less than half wavelength between arrays. By using the long baseline directly to estimate, we discuss the most suitable estimation method for multiple baseline interferometers to locate the ground targets.

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