Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, March 2004. / Thesis advisor(s): Frank E. Kragh. Includes bibliographical references (p. 151-153). Also available online.

隨著IEEE 802.11無線傳輸頻率的快速發展，而傳輸距離卻隨著縮短，使得我們考慮多跳接的傳輸方式來擴展通訊的範圍。但是在IEEE 802.11 的多跳接無線網路中並沒有服務品質的保證，而且在傳輸上的效能不高，因此我們希望在IEEE 802.11 多跳接的無線網路中改善傳輸效能且提供服務品質保證。在這篇論文中，我們提出了一個安排MAC存取的方法，來達到服務品質保證。我們使用一個樹狀架構來建構這個無線網路並且運作訊標繞樹的動作來建立我們的分離集合，而分離集合提供我們安排無衝突傳輸。當訊務流在這個網路中產生，我們的方法能夠有效的安排MAC存取並且保證不同類型訊務之品質。我們同時也提供一種適應性安排機制，來有效利用整個網路的效能，並且避免重新安排整個網路的MAC存取規畫，來維持網路品質在適當的滿意度。實驗結果顯示我們在多跳接的無線網路中有效的達到服務品質保證。 / With fast development of radio frequency, the wireless communication in IEEE 802.11 is growing up to high transmission rate (802.11g). However the distance of transmission decreases when wave frequency increases. Thus there is growing need to extend communication distance through multihop transmissions. But there is no QoS in IEEE 802.11 Multihop Wireless Networks; it has poor performance on transmission. Thus we are motivated to provide QoS in IEEE 802.11 Multihop Wireless Networks. In This Thesis, we propose a MAC Access Scheduling Scheme to support guaranteed QoS in IEEE 802.11 Multihop Wireless Networks. We use a tree-based architecture to construct the network and form the operation of token traversal. Token traversal operation builds the Disjoint Set to support scheduling collision-free transmission. When traffic is generated to the network, our scheme provides efficient schedule of MAC access and guarantee the QoS of different types of traffic. We also provide a adaptive scheduling to utilize the network performance and avoid the overhead of re-schedule to maintain the network quality at a satisfied level. The simulation results show we achieve the network QoS efficiently and provide guaranteed QoS.

Chan Chi Pan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves xiv-xv). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview --- p.1 / Chapter 1.2 --- Related Works --- p.1 / Chapter 1.3 --- Our Contributions --- p.2 / Chapter 1.4 --- Organization of the Thesis --- p.3 / Chapter Chapter 2 --- Definitions and Assumptions --- p.5 / Chapter 2.1 --- Data-collection Networks --- p.5 / Chapter 2.2 --- Assumptions --- p.9 / Chapter Chapter 3 --- Canonical Networks --- p.13 / Chapter 3.1 --- Theoretical Analysis --- p.13 / Chapter 3.1.1 --- Fixed Link Distance --- p.13 / Chapter 3.1.2 --- Variable Link Distance --- p.17 / Chapter 3.2 --- Simulation --- p.20 / Chapter Chapter 4 --- Beyond the Assumptions --- p.24 / Chapter 4.1 --- Multiple Interference --- p.24 / Chapter 4.2 --- HFD versus non-HFD performance --- p.27 / Chapter Chapter 5 --- Perfect Scheduling and IEEE 802.11 Scheduling --- p.30 / Chapter 5.1 --- Relationship between Perfect Scheduling and IEEE 802.11 Scheduling --- p.30 / Chapter 5.2 --- Throughput Analysis under IEEE 802.11 scheduling --- p.33 / Chapter Chapter 6 --- General Networks --- p.37 / Chapter 6.1 --- Discussion of HFP --- p.37 / Chapter 6.2 --- HFP Formulation --- p.39 / Chapter 6.3 --- Optimization in Finding Best HFP --- p.43 / Chapter 6.4 --- Experiment --- p.44 / Chapter 6.5 --- NS-2 Simulation --- p.47 / Chapter Chapter 7 --- Applying Canonical Network to General Networks --- p.49 / Chapter 7.1 --- Direct Application --- p.49 / Chapter 7.2 --- Manifold Canonical Network with Shorter Link Distance --- p.51 / Chapter 7.3 --- Robustness on Node Positions in Manifold Canonical Network --- p.54 / Chapter Chapter 8 --- Conclusion --- p.56 / Appendix A RTS/CTS and Power Control --- p.x / References --- p.xiv

Wong Tsz-Chun Stanley. / Thesis submitted in: July 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 58-61). / Abstracts in English and Chinese. / 摘要 --- p.III / ACKNOWLEDGEMENT --- p.IV / LIST OF FIGURES --- p.VIII / Chapter CHAPTER 1 --- INTRODUCTION --- p.2 / Chapter 1.1 --- Introduction --- p.2 / Chapter 1.2 --- Organization of the Thesis --- p.6 / Chapter CHAPTER 2 --- BACKGROUND STUDIES --- p.7 / Chapter 2.1 --- Overview of IEEE 802.11 --- p.7 / Chapter 2.3 --- 802.11b Network Type --- p.10 / Chapter 2.4 --- IEEE 802.11 MAC overview --- p.12 / Chapter 2.4.1 --- Distributed Coordination Function (DCF) / Point Coordination Function (PCF) --- p.13 / Chapter 2.4. --- Request-to-Send (RTS) / Clear-to-Send (CTS) --- p.14 / Chapter CHAPTER 3 --- QUEUE MANAGEMENT IN ACCESS POINTS --- p.16 / Chapter 3.1 --- Introduction --- p.16 / Chapter 3.2 --- Packet Delay Variation in Access Points --- p.17 / Chapter 3.2 --- Simulations Settings and Configuration --- p.19 / Chapter 3.2.1 --- Mobile Networking in NS2 --- p.19 / Chapter 3.2.2 --- Input Parameter of Shadowing Radio Propagation model --- p.22 / Chapter 3.2.3 --- Configuration of the simulation --- p.25 / Chapter CHAPTER 4 --- PERFORMANCE ANALYSIS OF 802.11B DOWNLINKS --- p.30 / Chapter 4.1 --- Introduction --- p.30 / Chapter 4.5 --- Assumptions of the analysis --- p.31 / Chapter 4.3 --- Proposed Queue Management in Access Point --- p.32 / Chapter 4.4 --- Channel error modeling --- p.34 / Chapter 4.5 --- The analytical model of downlinks --- p.35 / Chapter 4.6 --- Performance Calculation --- p.37 / Chapter 4.4 --- Simulation Result --- p.41 / Chapter 4.4.1 --- Extension of NS2 --- p.42 / Chapter 4.4.2 --- Configuration of the simulation --- p.44 / Chapter CHAPTER 5 --- RESOURCE ASSIGNMENT IN ACCESS POINTS --- p.48 / Chapter 5.1 --- Introduction --- p.48 / Chapter 5.2 --- Packet Delay Balancing --- p.49 / Chapter 5.2 --- Simulation Result --- p.51 / Chapter CHAPTER 6 --- CONCLUSION --- p.56 / BIBLIOGRAPHY --- p.58

Chen, Darui. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 62-67). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.iv / Table of Contents --- p.v / List of Figures --- p.vii / List of Tables --- p.viii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Motivation --- p.1 / Chapter 1.2 --- Related Works --- p.2 / Chapter 1.3 --- Contributions --- p.6 / Chapter 1.4 --- Organization --- p.8 / Chapter Chapter 2 --- Preliminaries --- p.9 / Chapter 2.1 --- MAC Protocol in IEEE 802.11 WLANs --- p.9 / Chapter 2.1.1 --- IEEE 802.11 DCF --- p.9 / Chapter 2.1.2 --- Performance Anomaly of DCF --- p.11 / Chapter 2.2 --- Multi-Rate WLANs with Rate Adaptation --- p.12 / Chapter 2.2.1 --- PHY-Layer Rate Adaptation Model --- p.12 / Chapter 2.2.2 --- Two Typical WLANs with Rate Adaptation --- p.13 / Chapter Chapter 3 --- Performance Analysis and Evaluation of Multi-Rate IEEE802.11 WLANs --- p.15 / Chapter 3.1 --- Theoretical Analysis of Multi-Rate IEEE 802.11 WLANs --- p.15 / Chapter 3.1.1 --- Markov Chain Model for Backoff Process --- p.15 / Chapter 3.1.2 --- Saturation Throughput --- p.18 / Chapter 3.1.3 --- Theoretical Throughput Limit and Dynamic Backoff --- p.20 / Chapter 3.2 --- Performance Evaluation of Multi- Rate WLANs --- p.22 / Chapter 3.2.1 --- Model Validation --- p.22 / Chapter 3.2.2 --- Theoretical Throughput Limit --- p.24 / Chapter Chapter 4 --- Rate-aware DCF Protocol --- p.30 / Chapter 4.1 --- Proposed R-DCF Protocol --- p.30 / Chapter 4.2 --- Theoretical Analysis of R-DCF --- p.34 / Chapter 4.2.1 --- Markov Chain Model for Backoff Process --- p.34 / Chapter 4.2.2 --- Saturation Throughput --- p.36 / Chapter 4.2.3 --- Simplified Models --- p.39 / Chapter 4.3 --- Performance Evaluation --- p.41 / Chapter 4.3.1 --- Model Validation --- p.41 / Chapter 4.3.2 --- R-DCF with Homogeneous Users --- p.42 / Chapter 4.3.3 --- R-DCF in Fixed-Rate WLANs --- p.49 / Chapter Chapter 5 --- Performance Enhancement of the R-DCF Protocol --- p.52 / Chapter 5.1 --- Maximizing Throughput of R-DCF --- p.52 / Chapter 5.2 --- Offline Adaptive Backoff Methods --- p.55 / Chapter Chapter 6 --- Conclusions --- p.60 / Bibliography --- p.62

Chan, An. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 80-84). / Abstracts in Chinese and English. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Motivations and Contributions --- p.1 / Chapter 1.2 --- Related Works --- p.3 / Chapter 1.3 --- Organization of the Thesis --- p.4 / Chapter Chapter 2 --- Background --- p.5 / Chapter 2.1 --- IEEE 802.11 --- p.5 / Chapter 2.1.1 --- Basic IEEE 802.11 Standards --- p.5 / Chapter 2.1.2 --- Types of Networks --- p.7 / Chapter 2.2 --- Voice over IP (VoIP) Codecs --- p.8 / Chapter 2.3 --- VoIP over WLAN --- p.9 / Chapter 2.3.1 --- System Architecture of VoIP over WLAN --- p.9 / Chapter 2.3.2 --- VoIP Capacity over an Isolated WLAN --- p.10 / Chapter Chapter 3 --- VoIP Capacity over Multiple WLANs --- p.12 / Chapter 3.1 --- Topology Settings and Assumptions --- p.12 / Chapter 3.2 --- Low VoIP Capacity Found in NS2 Simulations --- p.16 / Chapter 3.3 --- Applying Frequency Channel Assignment --- p.18 / Chapter Chapter 4 --- Clique Analysis and Call Admission Control --- p.21 / Chapter 4.1 --- Conflict Graph Model and Cliques --- p.21 / Chapter 4.2 --- Cliques in Multi-Cell WLANs --- p.22 / Chapter 4.3 --- Clique-Based Call Admission Control Algorithm --- p.24 / Chapter 4.3.1 --- Algorithm Description --- p.24 / Chapter 4.3.2 --- Algorithm Performance Evaluation --- p.27 / Chapter 4.3.3 --- Clique-Based Admission Control in Three-Frequency- Channel WLAN --- p.29 / Chapter Chapter 5 --- Time Division Multiple Access (TDMA) on IEEE 802.11MAC --- p.32 / Chapter 5.1 --- Coarse-Grained Time-Division Multiple Access (CTDMA) --- p.33 / Chapter 5.1.1 --- Basic Ideas of CTDMA --- p.33 / Chapter 5.1.2 --- Conflict Graph Modeling of CTDMA --- p.35 / Chapter 5.1.3 --- Parameter Values in CTDMA --- p.41 / Chapter 5.2 --- Possible Realization of TDMA on 802.11 Standards --- p.47 / Chapter Chapter 6 --- Coloring Problem in Wireless Networks: A Theoretical Treatment --- p.52 / Chapter 6.1 --- Coloring of One-Dimensional Linear Network --- p.53 / Chapter 6.1.1 --- Network with Same Link Length --- p.53 / Chapter 6.1.2 --- Network with Variable Link Length --- p.54 / Chapter 6.2 --- Coloring of Two-Dimensional Network --- p.63 / Chapter Chapter 7 --- Conclusion --- p.66 / Appendices --- p.69 / References --- p.80

Thesis (M.S. in Computer Science)--Naval Postgraduate School, March 2004. / Thesis advisor(s): Geoffrey Xie. Includes bibliographical references (p. 121-122). Also available online.

IEEE 802.11 is an economical and efficient standard that has been applied to vehicular networks. However, the long handoff latency of the standard handoff scheme for IEEE 802.11 has become an important issue for seamless roaming in vehicular environments, as more handoffs may be triggered due to the higher mobility of vehicles. This thesis presents a new and fast location-based handoff scheme particularly designed for vehicular environments. With the position and movement direction of a vehicle and the locations of the surrounding APs, our protocol is able to accurately predict several possible APs that the vehicle may visit in the future and to assign these APs different priority levels. APs on higher priority levels will be first scanned. Once a response to scanning from an AP is received, the scanning process ends immediately. A blacklist scheme is also used to exclude those APs that showed no response to the scanning during previous handoffs. Thus, time spent on scanning APs is supposed to be significantly reduced. The simulation results show that the proposed scheme attains not only a lower prediction error rate, but also a lower MAC layer handoff latency, and that it has a smaller influence on jitter and throughput; moreover, these results show that the proposed scheme has a smaller total number of handoffs than other handoff schemes.

Thesis (M.S. in Systems Engineering)--Naval Postgraduate School, September 2004. / Thesis advisor(s): Rex Buddenberg. Includes bibliographical references (p. 69-70). Also available online.

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xiii, 97 p.; also includes graphics (some col.). Includes bibliographical references (p. 94-97).