近年來，由於超寬頻 (Ultra Wide Band, UWB) 它驚人的高速數據傳輸率和

優異低功耗以及低干擾的特性，已成為無線個人區域網路(Wireless Personal Area

Network, WPAN)最受歡迎的技術之一。在眾多UWB信號中的最受歡迎的標準為

多頻帶-正交分頻多工系統(Multi-Band Orthogonal Frequency Division

Multiplexing, MB-OFDM) ，本論文將致力於此系統架構下對可能同時存在之受

保護通訊系統訊號的偵測技術。

在這篇論文吾人的主要目標為提出一有效的方法為在沒有執照的頻率使用發射

系統和已取得合法使用頻譜的系統的共存方式。為整個頻譜資源更合理有效的利

用，感知(Cognitive)的概念是一個很好的解決方法。感知的概念在於可以靈活地

意識到環境的變化以及隨時改變傳輸參數以適應環境，在這篇論文裡的吾人的目

標是設計最合適的窄頻干擾源(Narrow Band Interference, NBI) 檢測器(Detector)

在不同的傳輸環境下。根據我們所得到窄頻干擾源的傳輸參數多寡，我們利用

Neyman-Pearson理論來設計最合適的窄頻干擾源檢測器，這就是感知系統的概

念。本篇論文大致把我們的窄頻干擾源訊息分類作為完全知道窄頻干擾源的傳輸

參數除了它強度，以及不完全知道窄頻干擾源的傳輸參數。我們將更進一步以得

知窄頻干擾源的位置與否來進行探討。

吾人將按以下模式組織這篇論文︰首先介紹設計窄頻干擾源檢測器需要的

背景知識，包括Neyman-Pearson定理和GLRT檢測定理。在第3章我們開始提

出合適檢測器基於可得到的關於窄頻干擾源訊息的多寡，以所謂感知系統的概念

來設計。提出合適當下環境的檢測器之後，進行這個檢測器的性能分析。然後我

們進行大量的電腦模擬以證實分析的準確。

Spectrum sensing in cognitive radio (CR) is an emerging technology
which enables coexistence of systems; thus, the precious resources
of frequency bands can be utilized more efficiently. In this paper,
narrowband interference (NBI) detection in an orthogonal frequency
division multiplexing (OFDM) based cognitive radio system is
addressed. According to how much available information about NBI is
known to the detector, several detection algorithms based on the
Neyman-Pearson philosophy are proposed. In specific, the amount of
receiver's knowledge about NBI is classified into categories
according to whether or not a) the received power, b) the occupied
frequency bands, and c) the second moment descriptions of NBI are
available. In dealing with unknown parameters in the hypothesis
testing, generalized likelihood ratio test (GLRT) is employed.
Performance analysis is carried out for all proposed algorithms in
terms of the receiver operating characteristic (ROC). Extensive
computer simulations are run to verify the accuracy of the analysis.

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