In a multi-hop mobile ad hoc network (MANET), IEEE 802.11 power management may fail if power-saving (PS for short) stations are out of synchronization. To fix this problem, [8, 12, 15, 16] proposed various cyclic quorum-based power management (CQPM) protocols, which, however, may also completely fail if some PS stations have different schedule repetition intervals (SRIs). This implies that, from the viewpoint of duty cycle, CQPM is non-adaptive. Hence the authors of [1] proposed the first adaptive power management protocol, called AQEC. However, in AQEC, the values of SRI must be squares. This implies the adaptiveness (i.e., the number of tunable SRIs) of AQEC is very limited. Hence the authors of [14] proposed the first fully adaptive power management protocol, called HQS. However, in HQS, the duty cycle of a station is not optimal. To conquer all these problems, we propose the OFAA (optimal fully adaptive asynchronous) power management protocol, which has the following attractive features. (i) By means of novel beacon interval structures and the factor-hereditary quorum space techniques, OFAA ensures that two PS neighbors can discover each other in finite time regardless of their clock difference and their individual SRIs. (ii) Given the maximum SRI, Smax, the number of tunable SRIs for every PS station is Smax. (iii) The idle duty cycles for all SRIs are minimal. (iv) The time complexity of OFAA neighbor maintenance is constant. (v) A cross-layer SRI adjustment scheme is proposed such that a PS station can adaptively tune its SRI according to traffic QoS requirements. Both theoretical analysis and simulation results show that OFAA achieves better energy efficiency than existing adaptive CQPM protocols, including AQEC [1] and HQS [14].

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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.

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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.