許多行動隨意與無線感測網路的研究，例如：傳輸、覆蓋範圍、定位與安全等議題，都需要行動性的支援來提升它們的效能。本篇論文利用行動的支援節點幫助感測網路中的位置偵測與不相連隨意網路的資料傳輸。
　　目前已存在一些感測節點的定位機制，其中一部分需要測量點與點之間的距離，另外的則不需要。透過特定的硬體設備，測量距離或角度的方式可以達到高精確度；然而，不用測量距離或角度的方法雖然無法提供高精確度的位置資訊，但是在成本上的需求較少。本篇論文提出在二維與三維的無線感測網路中不需測量距離的定位機制，這個方法採用行動支援節點來幫助感測節點定位，這些行動支援節點裝備著全球定位系統隨意移動在感測區域中，並定期廣播它們的目前所在位置資訊，當感測節點取得這些資訊後，便可以計算它們的位置。這篇論文提出的定位方法感測節點不需要任何額外的硬體支援或資訊傳輸。實驗結果顯示這個定位方法超越其他不用測量距離或角度的方法。
　　由於節點的行動性或地形限制，一個隨意網路的拓撲可能被分割成許多部份，這個嚴重的分離問題影響資料傳輸與資訊可得性。然而，大多數之前提出的路徑選擇協定都假設隨意網路永遠連接。這篇論文提出兩個利用行動支援節點回復不相連行動隨意網路的移動機制，在邊界移動機制中，支援節點移動至網路分割的邊界處幫助連接不相連的網路。在區域移動機制中，行動支援節點沿著資料傳送區域移動進而幫助資料的轉送，兩個方法都是分散式並自行組成，並可以輕易地與路徑選擇協定整合。兩個移動機制都在網路模擬器ns-2實作，另外三個移動策略包含隨機固定、隨機移動與環行移動也進行效能分析與評估，實驗結果顯示邊界移動與區域移動機制能夠有效率地改善資料傳輸與連接分割的網路。

　　Many research challenges in mobile ad hoc and wireless sensor networks, such as capacity, transmission, coverage, localization, security etc., need mobility support to upgrade their performance. This thesis develops mobile assisting nodes to support localization process in sensor networks and to improve data transmission in disconnected ad hoc networks.
　　Localization is one of the substantial issues in wireless sensor networks. Several approaches, including range-based and range-free, have been proposed to calculate positions for randomly deployed sensor nodes. With specific hardware, the range-based schemes typically achieve high accuracy based on either node-to-node distances or angles. On the other hand, the range-free mechanisms support coarse positioning accuracy with the less expense. This thesis describes range-free localization schemes using mobile assisting nodes for two & three-dimensional wireless sensor networks. Each assisting node equipped with the GPS moves in the sensing field and broadcasts its current position periodically. The sensor nodes obtaining the information are able to compute their locations. With the scheme, no extra hardware or data communication is needed for the sensor nodes. Moreover, obstacles in the sensing fields can be tolerated. The localization mechanism has been implemented in the network simulator ns-2. The simulation results demonstrate that the scheme outperformed other range-free mechanisms.
　　An ad hoc network topology could be partitioned due to node mobility or geographic limitations. A serious problem, disconnection in the ad hoc network, thus affects both data communication and information availability. However, most previous routing protocols assumed that the ad hoc network was never partitioned. This thesis also utilizes the assisting nodes to recover the disconnected mobile ad hoc networks with two movement algorithms. With Boundary Movement Mechanism (BMM), the assisting nodes move to boundaries of network partitions for linking disconnected networks. With Zone Movement Mechanism (ZMM), the assisting nodes travel along the data delivery zones to help relaying packets. Both algorithms are distributed and self-organized. In addition, they can be easily integrated with routing protocols. Both algorithms have been implemented in the network simulator ns-2. Three other strategies, including random stationary, random movement, and circular movement, were also evaluated for performance comparison. The simulation results show that both BMM and ZMM can efficiently improve data delivery and recover the network partitions.

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