廖婉君臺灣大學：電機工程學研究所陳建宇Chen, Chien-YuChien-YuChen2007-11-262018-07-062007-11-262018-07-062006http://ntur.lib.ntu.edu.tw//handle/246246/53476超寬頻(UWB)是近年來被倍受矚目的無線上網技術，無論在學術界或業界都被廣泛討論著。它能提供每秒上百萬位元甚至每秒十億位元的高傳輸速率。由於其高傳輸速率、低功率的電力消耗和短距離傳輸範圍的特性，超寬頻被視為未來提供無線個人區域網路的重要技術。目前業界極力將之推展為新一代無線USB的技術；並在不久的將來，超寬頻無線傳輸技術可望取代WiFi，成為消費性電子產品與實現數位家庭的無線傳輸技術。目前有二套不相容之超寬頻標準各自發展中。其一為WiMedia超寬頻，採用多頻帶正交頻多分工(MB-OFDM)技術；另一套系統為UWB Forum所提倡的超寬頻，採用直接序列超寬頻技術。 目前眾多關於超寬頻之研究，多數探討在網路實體層中所遇到之困難和挑戰。然而，要有效的利用實體層提供之高傳輸速率，必須搭配有效率的媒介存取控制層。媒介存取控制層之主要功能為適當安排網路上的資源，避免實體層的碰撞並讓資料能正確無誤的在適當時間傳送到目的地。媒介存取控制層的機制對無線網路的效能影響非常大，也需要被詳盡的檢視。因此在本論文中，我們仔細地研究及頗析二套超寬頻技術的媒介存取控制層，了解並分析其中的差異。透過完整的介紹和一一對各項功能支援程度的比較和對照，希望能呈現對二套超寬頻技術的媒介存取控制層深入的展示，發現其問題，以及值得探討和研究的地方。Ultra-wide band (UWB) is a wireless communication technology under widely discussed recently. It can provide high transmission rate from hundreds of Mbps up to Gbps level. Combine the characteristics of high data rate, low transmission power, and short range coverage, UWB is considered to be suitable for the WPAN and received significant interests for future wireless communication from both academia and industry. The application of UWB includes wireless USB and wireless transmission of digital content in digital home. There are two main UWB standards existed, WiMedia Alliance UWB and UWB Forum. WiMedia UWB uses multi-band OFDM as its physical layer while UWB Forum adopts pulsed based direct-sequence UWB for its physical layer technology. MAC layer is on the top of the physical layer and is responsible for medium assess control mechanisms such as medium access and sharing, admission control, scheduling, power management, security, and so on. It affects the efficiency of the system performance a lot and may be waste of the bandwidth provides by the physical layer if it does not define carefully. We are going to look into the MAC layer mechanisms of both the alliances. By studying the MAC layer respectively, it’s possible to obtain the common and different parts of them, which gives us insight of the performance and direction of the future research issues. We provide a comprehensive overview on MAC layer and have a detail comparison between both systems.Chapter 1 Introduction 1 1.1 Related work 3 1.2 Motivation 4 1.3 Thesis organization 4 Chapter 2 WiMedia UWB MAC 5 2.1 Superframe structure 5 2.2 Group component 6 2.3 Beacon period (BP) overview 6 2.3.1 Beacon period state 7 2.3.2 Beacon transmission and reception 7 2.3.3 BP contraction 8 2.3.4 Beacon collision detection 8 2.3.5 Merger of multiple BPs 9 2.4 Prioritized channel access (PCA) 10 2.5 Distributed reservation protocol (DRP) 11 2.6 Synchronization 13 2.7 Power management 13 2.8 Dynamic channel selection 14 2.9 Security mechanism 14 2.10 Range measurement 15 Chapter 3 IEEE 802.15.3 MAC 16 3.1 Piconet and its component 16 3.2 Superframe structure 17 3.3 Channel time management 18 3.3.1 Contention access period (CAP) 18 3.3.2 Channel time alloction (CTA) 18 3.3.3 Request CTA 18 3.3.4 Management CTA (MCTA) 19 3.4 Other piconet functionality 20 3.4.1 Dependent piconet 20 3.4.2 Association to the piconet 21 3.4.3 Fast connection time 22 3.5 Handover of the PNC 22 3.6 Changing piconet parameters 23 3.7 Dynamic channel selection 24 3.8 Information discovery 24 3.9 Power management 25 3.10 Security mechanism 25 Chapter 4 MAC layer comparison between WiMedia UWB and UWB Forum 27 4.1 System structure 27 4.1.1 Network coverage 27 4.1.2 Multi-hop transmission 28 4.1.3 Coexistence of clusters 29 4.1.4 Superframe length and structure 30 4.1.5 Summary 31 4.2 System management functionality 31 4.2.1 Beacon period 31 4.2.2 Establish a network 32 4.2.3 Join existed network 32 4.2.4 System information exchange 33 4.2.5 Number of supportable devices 34 4.2.6 Summary 34 4.3 Medium access method for non-QoS data 35 4.3.1 Summary 37 4.4 Medium access method for QoS streams 37 4.4.1 Summary 39 4.5 Other characteristics 40 4.5.1 ACK policy and retransmission support 40 4.5.2 Synchronization between devices 41 4.5.3 Power management 41 4.5.4 Security modes 42 4.5.5 Summary 42 4.6 Theoretical performance analysis 42 4.6.1 Access delay time for TDMA slots 43 4.6.1.1 WiMedia MAC analysis 43 4.6.1.2 IEEE 802.15.3 MAC analysis 45 4.6.1.3 Summary 46 4.6.2 Theoretical capacity of MAC layer 46 4.6.2.1 WiMedia capacity 47 4.6.2.2 IEEE 802.15.3 capacity 47 4.6.2.3 Summary 48 Chapter 5 Conclusion and future work 49 5.1 Conclusion 49 5.2 Future work 50 Reference 51434086 bytesapplication/pdfen-US超寬頻無線個人區域網路UWBWiMediaUWB ForumWPANthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/53476/1/ntu-95-R93921097-1.pdf