在無線感知網路(CRNs)中，次級用戶(SUs)在不干擾授權用戶的通信服務品質的狀況下，有機會可以使用暫時沒有被使用的頻譜。用戶必須與另一個用戶在相同頻譜會合並建立通訊連線。傳統的會合演算法假設每個用戶只配備了一個感知無線電，這幾年來，隨著無線收發器價格的大幅下降，在用戶上裝配多個感知無線電藉以減少會合所需時間的方法變得更加可行。在本篇論文中，我們提出一套基於中國餘式定理所設計的多感知無線電的頻道會合(CRT-based Multi-radio Rendezvous)演算法，這個演算法可以在異質無線感知網路下使用，而異質無線感知網路指的是網路中的每個使用者可能有不同頻譜感知能力。我們所設計的演算法可以在O((N_1 N_2)/(m_1 m_2))時間內達到最大的交會多樣性，在此N_1跟N_2所指的是需要會合的兩用戶各自的可用頻道數目，而m_1跟m_2指的是兩用戶各自擁有的感知無線電數目。模擬結果顯示我們所設計的方法可以比已知的會合演算法有更好的表現。

In cognitive radio networks (CRNs), secondary users (SUs) can utilize the temporary unused spectrum opportunistically without affecting the quality of services of the licensed users, also called primary users (PUs). It is a fundamental operation for user to rendezvous with another user on the same channel and establish a communication link. Traditional rendezvous algorithms assume homogeneous CRNs and each user equipped with a single radio. In recent years, the cost of wireless transceivers has fallen dramatically. It is more feasible for users to apply multiple radios to reduce the time to rendezvous (TTR) significantly. In this thesis, we propose a CRT-based Multi-radio Rendezvous (CMR) algorithm for heterogeneous CRNs, where the users are unaware of total number of channels and are allowed to have different spectrum-sensing capabilities. Our CMR scheme applies Chinese Remainder Theorem (CRT) to achieve maximum rendezvous diversity within O((N_1 N_2)/(m_1 m_2)) time, where N_1 and N_2 are the number of available channels of two users and m_1 and m_2 are the number of radios of two users. Simulation results show that CMR has better performance than the previous works.

Chapter 1 Introduction 1
Chapter 2 Related Work 5
Chapter 3 CRT-based Multi-Radio Rendezvous Algorithm (CMR) 10
3.1 System Model 10
3.2 Problem Definition 11
3.3 CRT-based Channel Hopping Scheme 12
3.3.1 Rendezvous through CRT 12
3.3.2 Algorithms 17
3.4 Time Complexity Analysis 24
3.5 Performance Analysis 25
Chapter 4 Performance Evaluation 27
4.1 Impact of the T_α 28
4.2 Impact of the Number of Licensed Channels 29
4.3 Impact of the Number of Radios 31
4.4 Impact of the Number of Common Channels 33
4.5 Impact of the Number of Available Channels 35
Chapter 5 Conclusion 38
References 39

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