配置控制通道是感知無線網路中的一項重要挑戰。許多現有的頻譜分配演算法均假設頻譜中存在全域控制通道。然而現實條件下，頻譜並不充足。因此提供給次要使用者一個主要使用者不使用的全域控制通道並不實際。為了解決控制通道配置問題，叢集概念被提出。演算法令同一叢集中的控制通道相同。將傳輸延遲減少到只發生於叢集與叢集之間。這篇論文提出「以可利用性為基礎的控制通道配置機制」與「相似地理區域特性」。相似地理區域特性存在於感知無線網路。根據相似地理區域特性，次要使用者會選擇最高可利用性的頻道做為控制通道。相似地理區域的次要使用者們將因此組成叢集。同時，重新建立叢集的機率被降至最低。次要使用者不需要交換訊息來收斂叢集，也不需要在叢集內部傳遞訊息，只需要在特定事件發生時，掃描一個頻道，便可以定義自己是否為負責叢集與叢集之間通信的橋樑節點。橋樑節點僅需要在兩個頻道之間切換，便能夠和大部分的鄰點溝通。模擬顯示，在大部分的環境下，端對端平均延遲時間小於比較對象。在各種數量的頻道環境中，性能表現得良好而且穩定。

Assigning control channel in cognitive radio networks is a challenge. Many existing spectrum decision algorithms assume that the common control channel exists. However, the spectrum is insufficient in practice. It leads to the existing impracticality of a global common control channel for all secondary users. One of the common substitution for global common control channels is constructing clusters. It describes that each cluster has its local common control channel. This thesis proposes an algorithm "availability-based control channel assignment" and the region-similarity characteristics which exist in cognitive radio network. Secondary users choose the highest availability channel as the control channel. Based on the region-similarity characteristics, the region-similarity secondary users will belong to the same cluster automatically, and the probability of re-cluster process occurrence is minimized. Namely, Secondary users do not need to converge to clusters by exchanging messages. Moreover, when bridge nodes need to do inter-cluster communication, this algorithm ensures that the secondary users have known which channel they should choose. The channel has the better availability than other channels. In the simulation, the performance of end-to-end delay is better than other algorithms in most of the cases.

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