IEEE 802.22 無線廣域網絡是全世界第一個使用應用感知無線電的網絡規格。對執照使用者不造成干擾的情況下，它利用未被使用的執照頻段來進行無線通訊。這項措施緩解了目前免費頻段處於飽和狀態情況。此論文會先介紹IEEE 802.22的基本規格以及架構。接著會繼續講解此網絡的各個基地台共存問題以及資源分配議題。這篇論文以提出兩個機制為主要的貢獻。第一個機制稱為“框架重複使用分配法”，而第二個機制則稱為“動態資源區塊重複分配法”。

框架重複使用分配法適用於多個基地台共同使用單一頻道的情況下。框架重複使用分配法又分成分散式和中樞式兩種。這兩種方式都是為了能在各個不相鄰的基地台重複使用同一個框架而提出的。此方法的利弊以及必需付出的代價皆會一一討論列出。框架重複使用分配法的性能分析以及模擬結果皆證明了此方法可以用來提升框架的使用數量，以及解決因缺乏資源導致離線的問題。

動態資源區塊重複分配法是為了剋服框架重複使用分配法的缺陷而提出的另一個機制。動態資源區塊重複分配法可適用於多個基地台使用多個頻道的情況。動態資源區塊重複分配法可讓一個未被任何基地台使用資源區塊被各個不相鄰的基地台重複使用。此方法的利弊以及必需付出的代價皆會一一討論列出。動態資源區塊重複分配法的性能分析以及模擬結果皆證明了此方法可以在不改變原本系統架構的情況下提高基地台的傳輸量。此外，動態資源區塊重複分配法減少了資源分配所需的時間，並且簡化了釋放資源的過程。動態資源區塊重複分配法也能夠根據各個基地台目前網絡的擁塞程度進行資源區塊的分配。

IEEE 802.22, which was developed for wireless regional area networks (WRANs), is the first Cognitive Radio (CR) enabled network standard. It helps to solve spectrum shortage problem by making use of licensed spectrum on the premise that it will not cause interference to licensed users. This thesis will start with an introduction of basic structure of IEEE 802.22. Then the self-coexistence mechanism and resource allocation issues will be discussed. Two mechanisms called “Frame Reuse Allocation (FRA)” and “Dynamic Resource Block Reuse (DRBR)” are proposed, which are the main contribution of this thesis.

The FRA mechanism can be used when multiple adjacent base stations operating on the same channel. FRA mechanism is proposed in the distributed and centralized way. Both of the ways try to reuse a same frame in multiple cells that are not adjacent with each other. Their advantages and disadvantages as well as their trade-offs will be discussed. The performance analysis and simulation results show that FRA mechanism can be used to increase the number of frame usage, and address the forced disconnection problems which will decrease the QoS.

The DRBR mechanism is proposed to overcome the deficiencies of FRA mechanism. DRBR mechanism can be used when multiple adjacent base stations operating on different channels. DRBR allows an unused resource block can be used by multiple cells that are not adjacent with each other. Its advantages and disadvantages as well as the trade-offs will be discussed. The performance analysis and simulation results show that DRBR mechanism can increase a cell throughput without changing the original system structure. Besides, the overhead cost in resources allocation is reduced and the process in resource releasing is simplify. DRBR mechanism can also response to different traffic situations according to the blocking rate of different base stations.

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