- 學位論文
合作式感知無線電於相關性信號環境的研究
A Study of Correlative Signal Channel on Cooperative Spectrum Sensing for Cognitive Radio Networks
摘要
為了獲得頻譜紅利，頻譜感知認知無線電透過合作式通訊可以帶來合作增益，為了進一步討論時間與空間相關性對感知系統性能所帶來的影響, 本論文將分別討論在通道以及時間樣本相關的情形下對正確感知機率與誤警機率的改變，另外也考慮了主用戶信號處在快速衰減通道的情形。 為了模擬此情形，本論文建構了考慮相關矩陣的樣本相關矩陣的信號模型，並針對分別討論了合作感知中的硬規則(Hardrule)多數決投票法(Majority)與軟硬融合(Hibrid)的加權投票法(Weight)做了的模擬分析。並且，針對排序後加權法做了進一步的模擬與分析。排序加權法是一個基於多數決硬融合為基礎做估計的演算法，在高信雜比時可有效降低有效降低所需要的感知節點數目。 本文將證明此方法具備穩健性，可降低回報通道的開銷(overhead)，以及在環境與充滿不確定性的通道環境中仍具備穩定的感測能力。
並列摘要
For the purpose of obtaining the spectrum dividend, spectrum-aware cognitive radio can bring cooperative gain through cooperative communication. Among the influence of temporal and spatial correlation on the performance of the sensing system, this thesis will discuss the situation related to fading channel and spatial-time samples respectively. The change in correct perception probability and false alarm probability is also considered, and the primary user signal is considered to be in the fast-fading channel. In order to simulate the situation, this thesis constructs a signal model of the sample correlation matrix of the correlation matrix, and discusses the weighting of the majority hard fusion rule in cooperative cognition. The simulation were done by the weighted-voting fusion and then carried out by sorted-weighting fusion method. The sorted-weighting fusion is another algorithm based on the weighting-majority combining rule, which can effectively reduce the number of sensing nodes needed especially in the high SNR region. This thesis will also demonstrate the robustness of this approach, reduce the overhead of the reporting channel, still with the capabilities of sensing stably in the uncertain channel environment.