近年來, 感測網路因很多個低成本、低功率和微型的感測器的組成而被廣泛地應用。無線感測網路
中的感測器需要處理重要且複雜的資訊, 經由無線通訊傳送給合法使用者, 因感測器大部分是在開放
空間傳輸訊息, 在傳送的過程中容易被竊聽者竊聽,由於現實中每個通道環境的狀況不同,因此融合中
心須具備有通道狀況選擇的能力來確保接收正確的資訊。
本篇論文主要考慮感測器至接收端的通道為雷利衰減通道,當感測器傳送訊息時, 融合中心會優先
選擇通道增益較佳的來接收, 並且利用似然比測試分析其接收的資訊使其錯誤率最小, 並使竊聽者的
錯誤率不低於某一設定需求。

In recent years, wireless sensor networks are widely used because they comprised a large
number of low-cost, low-power and miniature sensors. In wireless sensor networks, the sensors
need to deal with the important and complex information, moreover, they transmit across a
wireless communication network to legitimate users. Since most of the sensors transmit message
in open area, the eavesdroppers are easy to tap in the transfer process. Owing to each channel
environment is different in reality, the fusion center must have the ability of channel selection
to ensure that correct information is received.
In this thesis, the channels considered from sensors to receiver are Rayleigh Fading Channel.
When sensors transmit message, the FC will prioritize in choosing the better channel gain to
receive signals. Likelihood Ratio Test is then used to analyze the received data in FC and
achieve the smallest FC’s error probability while maintaining the eavesdropper’s error probability
not lower than a required value.

論文審定書 i
摘要 ii
Abstract iii
1 序論 1
1.1 介紹. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
1.2 文獻回顧. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3 研究動機與方法. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
1.4 論文架構. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 系統模型與閥值判斷準則 4
2.1 系統模型. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2 融合中心判斷準則. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3 竊聽者判斷準則. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3 模擬結果和分析 11
3.1 模擬方法設計. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.2 模擬結果. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
4 結論 22
參考文獻 23

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