近年來隨著網路的蓬勃發展，無線感測網路已經成為一個眾所矚目的熱門研究課題，其中分散式感測網路是目前最常用的無線感測網路類型。只要藉由多個分散式感測器與一個資料融合中心，就可架構出分散式感測器網路。但由於感測器有電力、頻寬和處理…等資源限制，當一感測器電力耗盡時，此感測器便無法繼續運作。因此在無線感測網路上功率消耗，並發揮最大的傳輸效能與網路生命期為一個重要的課題。在本論文中，我們考慮了在無線感測網路中正進行著分散式估測的任務，首先感測器針對目標訊號進行接收，每一個感測器都可以根據其觀測結果得到一個觀測數據。然後每一個感測器將觀測數據經由通訊通道傳送回資料融合中心，最後所有的數據帶進融合規則得到此訊號的估測值。如何在維持著一定的估測品質下，延長網路生命期是本論文的目標。在延長網路生命期的考量下，我們設計了機率式感測器選取演算法以及最小化中斷機率式功率分配機制。在論文的模擬部分，將根據機率式感測器選取演算法、最小化中斷機率式功率分配機制以及最小化傳輸功率式功率分配機制，設計了三個網路生命期模型來延長並且比較彼此的網路生命期。模擬的最後結果顯示出，我們所提出的方法不僅可以提高網路的整體生命期，另外也能提高網路中每個感測器消耗功率的效益。

[1] Y. Chen and Q. Zhao, “On the Lifetime of Wireless Sensor Networks,” IEEE Commun. Lett., vol. 9, pp.976-978, Nov. 2005.
[2] Y. Chen and Q. Zhao, “Maximizing the lifetime of sensor network using local information on channel state and residual energy,” in Proc. Conf. on Information Science and Systems (CISS), Mar. 2005.
[3] J.-J. Xiao, S. Cui, Z.-Q. Luo, and A. J. Goldsmith, “Power scheduling of universal decentralized estimation in sensor networks,” IEEE Trans. on Signal Proc., vol. 54, no. 2, pp. 431–422, Feb. 2006.
[4] S. Cui, J. Xiao, A. Goldsmith, Z.-Q. Luo, and H. V. Poor, “Estimation diversity and energy efficiency in distributed sensing,” IEEE Trans. on Signal Proc., vol. 55, no. 9, pp. 4683 – 4695, Sept. 2007.
[5] S. Cui, J. Xiao, A. Goldsmith, Z.-Q. Luo, and H. V. Poor, “Energy-efficient joint estimation in sensor networks: Analog vs. digital,” in Proc. IEEE Intl. Conf. Acoustics, Speech and Sig. Proc. (ICASSP), pp. 745–748, Mar, 2005,
[6] J. Wu, Q. Huang and T. Lee, “ Minimum Energy Decentralized Estimation via Exploiting the Statistical Knowledge of Sensor Noise Variance,” IEEE Trans. on Signal Proc., vol. 56, vo. 5, pp. 2171-2176, May, 2008.
[7] Y. Chen, Q. Zhao, V. Krishnamurthy, and D. Djonin, “Transmission scheduling for optimizing sensor network lifetime: a stochastic shortest path approach,” IEEE Trans.on Signal Proc., vol. 55, no. 5, pp. 2294– 2309, May 2007.
[8] B.-H. Cheng, A. Nosratinia, and K. Yao, “Lifetime Maximization for Joint Estimation in Wireless Sensor Networks.” in Proc. Asilomar Conf. on Signals, Systems and Computers (ACSSC), Nov, 2006.
[9] Javier Matamoros and Carles Ant´on-Haro, “Opportunistic Power Allocation and Sensor Selection Schemes for Wireless Sensor Networks.” IEEE Trans. on Wireless Comm., vol. 9, no. 2, July 2010
[10] J. Matamoros and C. Ant´on-Haro, “Opportunistic power allocation schemes for the maximization of network lifetime in wireless sensor networks,” in Proc. IEEE Intl. Conf. on Acoustics, Speech and Signal Processing (ICASSP 2008), pp. 2273–2276, April 2008.
[11] J. Li and G. AlRegib, “Network Lifetime Maximization for Estimation in Multi-hop Wireless Sensor Networks,” IEEE Tans. on Signal Proc., Vol. 57, No. 7, pp. 2456 - 2466, July 2009.
[12] W.-J. Huang, Y.-W. Hong and C.-C. Jay Kuo, “Lifetime maximization for amplify-and-forward cooperative networks,” IEEE Trans. on Wireless Comm., vol. 7, no. 5, May 2008
[13] S. M. Kay, “Fundamentals of Statistical Signal Processing: Estimation Theory,” Prentice-Hall, 1993.
[14] Edwin K. P. Chong and Stanislaw H. Zak, “An Introduction to Optimization,” Third Edition, Wiley, 2008.
[15] S. Boyd and L. Vandenberghe, “Convex Optimization”. Cambridge univ. press, 1993.