本篇論文研究方向著重在無線感測網路(Wireless Sensor Networks, WSN)的二元分散式偵測問題，以及融合中心(Fusion Center, FC)未知目標發生區域內的感測器數目。在無線感測網路中，由於感測器電力來源和通訊通道的頻寬是有限的，所以我們在感測器端提出一個新審查系統達到高效率的電源使用與較低的通訊傳輸率。在融合中心使用時序偵測(sequential detection)期盼能否大量減少融合中心接收感測器傳送訊號的次數。由模擬的結果我們可以看到,感測器使用的最少平均個數可經由適當地選擇審查機率來達到。

This thesis considers the problem of distributed sequential detection in wireless sensor networks (WSNs), where the number of operating sensors is unknown to the fusion center. Since the energy and bandwidth of communication channel are limited in WSNs, we employ the censoring scheme in the sequential detection to achieve energy-efficiency and low communication rate. Specifically, we show by simulations that employing censoring scheme can reduce the number of local decisions that required for the fusion center to make a final decision. The results implies that the energy conservation does not necessary degrade the performance of sequential detection in terms of the expected local decisions required for making a final decisions.

誌謝. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i
中文摘要. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
英文摘要. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
目錄. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
圖目錄. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
第一章 序論 1
1.1 無線感測網路和分散式偵測. . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 研究動機. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3 論文架構. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
第二章 使用審查決策法則的分散式偵測系統 3
2.1 審查系統. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.1 簡介審查系統. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.2 問題陳述. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1.3 新的審查系統. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2 系統架構. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
第三章 時序偵測法則 8
3.1 未知感測器節點的時序偵測法則. . . . . . . . . . . . . . . . . . . . . . . 8
3.1.1 簡介時序偵測法則. . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.1.2 時序偵測法則的門檻值. . . . . . . . . . . . . . . . . . . . . . . . 10
3.1.3 運用時序偵測法則所需的平均次數. . . . . . . . . . . . . . . . . . 11
3.2 理論分析. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.3 模擬結果. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
第四章 結論 21

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