在論文中，作者設計了一個適用於感知無線電中多重訊窗頻譜估測器之最佳化偵測器。所提出的最佳偵測器主要是要解決Thomson[1]的多重訊窗頻譜估測器在感知無線電中執行頻譜掃描(spectrum sensing)應用時的缺陷與不足之處。感知無線電要執行頻譜掃描時，多重訊窗頻譜估測器會先用來執行頻譜估測，接著所提出的偵測器用來檢測空閒的頻段以及擁有使用頻段的執照擁有者。那些被偵測出的空閒頻段可以提供感知無線通訊使用者來通訊，如此，可以使得整個頻譜資源獲得更有效的使用。

所提出來的偵測器是根據Neyman-Pearson規範去找出最佳化的設計。對於此偵測器而言，它的偵測效能理論值在數學上被完整的推導出來，並且透過電腦數值模擬獲得一致性結果驗證。另外，所提出來適用於多重訊窗頻譜估測器之最佳化偵測器不需透過合作式的偵測機制就可以達到可靠的偵測效能。相較於傳統的能量式偵測器[2]，在執行頻譜偵測時，所提出來的偵測器可以透過(多重)不同的Slepian訊窗達到更佳的偵測率與更好的強健性。對偵測效能而言，比起合作式自相關機制的偵測器[3]，所提出的偵測器高出大約48%的偵測率並且在訊雜比上擁有3dB的增益。最後，所提出適用於感知無線電中多重訊窗頻譜估測器之最佳化偵測器，對於最少所需要的觀察樣本數方面，比起能量式偵測器節省了約73.3%的觀察樣本數，即可達到相同的偵測效能。

In this thesis, the author proposes an optimal detector for the Thomson’s multitaper spectral estimation (MTSE) [1] in cognitive radios for spectrum sensing. The MTSE is used for
spectral estimation and then the proposed detector can detect primary users and spectrum holes for secondary users in cognitive radios. This proposed detector is designed and optimized based on the Neyman-Pearson Theorem. The analytical detection performance (probability of detection) of detecting primary users (PUs) and spectrum holes in spectrum sensing is mathematically formulated, studied, and verified by simulations. The proposed detector for the MTSE is non-cooperative in spectrum sensing and can perform blind spectrum sensing without prior knowledge of the primary users. Compared to the conventional energy detector
[2], the proposed detector is more reliable and robust for various multiple Slepian tapers. The proposed detector outperforms the cooperative autocorrelation-based detectors [3] in detection rate by 48%and with 3dB gain in SNR performance. Moreover, the minimumrequired observation size is smaller than the conventional energy detector by a reduction of 73.3%.

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