In this thesis, although we have proposed effective CUSUM-based algorithms to tackle the spectrum sensing problem in a sequential manner, the efficiency of proposed algo-rithms has not been analyzed. Since our formulation captures possible fading effects between the cognitive and the primary user, the detection problem we deal with involves non-homogenous and innately dependent observations after the reoccupying of the coex-isting primary system contrast to homogenous-distributed and independent observations after change in conventional quickest detection. Besides, we also emphasize the situa-tion where we could make use of known feature of primary signaling during detecsitua-tion process. These properties exclude existing available analysis about CUSUM procedures under minimax formulation on the optimality or asymptotic behavior to the best of our knowledge as yet.
As for cooperation schemes, future work might consider the design of the quantiza-tion strategy on the local sensors with memory or take the dependency among quantized versions of observations into account as designing the decision rule of global CUSUM test. Another aspect for future work is to include the design of power allocation under cooperative schemes as we consider more practical situation where the levels of channel conditions among involved cognitive users are not identical.
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作者簡歷
學生劉藹璇，民國七十五年五月二十日出生於台北市。民國九十三年九月自 新竹女中以申請入學管道進入國立交通大學電子工程學系，期間得過電工系書卷 獎四次、潘文淵文教基金會九十六年度獎學金，擔任過系學會學術組組長，並於 民國九十七年六月以班上第五名畢業於國立交通大學電子工程學系。民國九十七 年九月以推甄入學就讀國立交通大學電子研究所，跟隨簡鳳村教授從事即時變化 檢測於無線感知通訊網路之相關研究，碩士論文題目為《CUSUM-Based Quickest Spectrum Detection in Cognitive Radio Networks》，期間得過電子所系統組書卷獎 一次，並獲選為九十九年度中華民國斐陶斐交通大學分會之榮譽學員。