近來由於VLSI, 微處理器以及無線傳輸科技方面的進步, 使得無線感測器(sensor)的體積因而可以縮小,
且具備更豐富的計算及通訊的功能. 這種微小的無線感測器不但能夠偵測環境現象, 並且可處理收集到的數據, 並將處理過後的資料以無線傳輸的方式送到基地台. 我們可以佈置數以千計的感測器在一廣大的區域裡, 藉由自主的偵測資料, 感測器彼此的互相溝通, 構成所謂的無線感測器網路(wireless sensor network).

在wireless sensor network的應用中, 都擁有一各共同的特性, 就是資料要不斷地由某一地點傳往另外一地點, 然而, 因為sensor的能量是有限的, 所以在設計data-dissemination的策略時, 要特別注意能源消耗的考量, 避免資料遺失. 因此需要發展出一套資料傳輸的策略(Data-dissemination)來確保資料可以正確無誤的傳送到目的端.

本論文利用換手的方式設計出一個具有低energy consumption且load balance的資料傳輸模式. 最後我們也以實驗的結果來證明我們所提出的方法可以延長sensor network的壽命.

Recent advances in VLSI, microprocessor and wireless communication technologies have enabled the minification of wireless sensor's size and enriched the capability of its computing and communication. These small wireless sensors can sense the environmental phenomenon, process the collecting data, and deliver the data to the basestation by wireless communication.
We could deploy thousands of small wireless sensors which sense data actively and communicate with each other over a vast field to construct the wireless sensor network.

The common property of the wireless sensor network application is the constant data transmission. Because the energy of a sensor is constrained, we focus on the subject of sensor's energy consumption when developing a data dissemination model to avoid data lost. It is necessary to develop a data dissemination model to make sure the successful data transmission.

In this thesis, we develop a low energy consumption and load balance data dissemination model by hand-off. Finally, the performance results show that our alogrithm indeed extend the sensor network lifetime.

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