在行動無線感測網路中，了解節點的移動模式是很重要的。有許多應用需要節點及附近的節點一起協作來完成，例如以資料為中心的應用。許多社交工程的研究或是野生動物觀察與追蹤也需要知道許多個體與個體間的互動情形。因此，了解節點間的互動模式是很重要的。在這篇論文中，我們提出一個基於虛擬座標的共同移動節點偵測方法。我們使用最大獨立集合的幾何特性來發展我們的虛擬座標系統。建立這樣的座標系統耗費成本很低並且相對準確，我們建立一個類似極座標的系統，只需一些坐標旋轉及可使虛擬座標與真實做標相符合。我們藉由虛擬座標的幫助來進行共同移動節點偵測。一套制定良好的比較規則能精準地判斷共同移動的節點。使用這種方法不需要精確的定位技術因此我們的方法是非常有效率的。

In mobile wireless sensor networks, it is important to understand the moving pattern of sensor nodes. There are a lot of application that need sensors nearby to co-work, such as data centric applications. Thus, knowing the co-moving nodes will be helpful to these applications. In this thesis, we propose a co-moving sensor nodes detection mechanism based on virtual coordinate system. We use the geometric property of independent set to build our virtual coordinate system. The cost of building a virtual coordinate in this way is low and the result is relative accurate – just a coordinate rotation will it matches true coordinates. With the aids of virtual coordinate system, we can find out co-moving sensor node pairs efficiently since no precise localization scheme needed in our works. A well-defined comparison rule is used for co-moving detection.

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