在過去幾年中，由於網路的蓬勃發展，無線感測網路已成為一個熱門的研究議題，其中又以分散式感測網路為最主要的網路類型。利用多個散佈在外的分散式感測器，並且透過一個資料融合中心來負責接收訊號並處理資訊，這便是分散式感測網路。在現實生活中，由於感測器有電力上的限制，因此在無線感測網路上如何發揮最大傳輸效率並維持網路生命週期為一個重要的議題。在過去的研究中，作者利用最小化中斷機率式功率分配機制達到延續網路生命週期的目的，由此研究得知維持無線感測網路的多樣性為延長網路生命週期的主要原因。
在本研究中，我們考慮在無線感測網路的環境底下執行分散式估測任務，在資料融合中心，透過由無線感測器所提供的觀測數據來得到此訊號的估計值，另外，我們將對無線感測網路多樣性有更進一步的定義，並且利用這項特性設計新的功率分配機制，在論文中的模擬部分，將會和過往的功率分配機制(最小化傳輸功率分配及最小化中斷機率式功率分配)互相比較網路生命週期。最後模擬的結果顯示出，我們所提出藉由維持無線感測網路多樣性以及避免過大功率消耗之下所設計出來的功率分配機制，能夠更進一步地提高網路的生命週期。

Network lifetime is a typical topic in wireless sensor network since the power supply of wireless sensors is energy limited and non-rechargeable. In this thesis, we consider a distributed estimation system, if we want to maintain the estimation quality and extend network lifetime, the research literature [10] has shown that the minimum next round outage probability (MNROP) strategy outperforms minimum total transmission power (MTP) strategy, the potential property of MNROP is keeping the network diversity. Therefore, we will discuss and analysis the diversity order of distributed estimation process in an inhomogeneous network system, and propose a improve power allocation strategy based on diversity information. Finally, the simulation result showed that proposed strategy can effectively maintain the contribution of high diversity order sensors, and has excellent performance on network lifetime.

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