本文研究面向可靠的無線傳感器網絡的協議設計，測試和診斷。 / 在協議設計方面，我們集中研究媒體接入層的協議設計。首先，我們為水下無線傳感器網絡提出一個有效的媒體接入層協議RAS 。這個協議利用了水下無線傳感器網絡和地面無線傳感器網絡的媒體傳輸時延的差別，采用了並行傳輸的優先級方法。由于會導致碰撞，這種並行傳輸的方法不能被用在地面無線傳感器網絡中。該方法為高負荷的傳感器節點分配更長的傳輸時間。這種具有優先級的機制也同時提高了公平方面的性能。第二，我們處理水下無線傳感器網絡中由于報文失導致的不可靠的問題。基于之前提出的協議RAS ，我們提出了可靠的RAS 協議。該協議可以在可靠性和有效性方便達到一個平衡。它里面的報文確認和重傳機制同傳統的方法不同，所以它可以在提高可靠性的同時保證吞吐量不會被大幅降低。 / 第三，在協議測試方面，我們設計了RealProct ，一種新的可靠的用于無線傳感器網絡的一致性協議測試(測試協議實現是否符合協議規範)的架構。RealProct 采用了實際的傳感器節點來保證測試盡可能的接近實際部署。為了節省使用大規模實際部署來測試的硬件成本和控制成本， RealProct 使用少量傳感器節點虛擬各樣的拓撲結構和事件。同時，測試執行和裁決算法也用于最小化測試用例執行次數，並保證假陰和假陽錯誤低于給定值。 / 最後，我們提出了MDiag，一種使用移動智能手機巡視無線傳感器網絡並診斷網絡錯誤的方法。由于該智能手機不是無線傳感器網絡的組成部分，因此該診斷不會像其它已有的診斷方法那樣影響原無線傳感器網絡的運行。並且，使用智能手機巡視並診斷無線傳感器網絡比部署另一個用于診斷的網絡更有效。在巡視過程中，無線傳感器網絡所交互的報文被收集起來，然後被我們所設計的報文解析器所分析。然後，我們設計了統計性規則來指導異常現象的診斷。為了提高巡視效率，我們提出了一個巡視方法MSEP。 / 我們做了大量實驗驗證以上提出的方法和算法，結果表明它們在達到可靠性無線傳感器網絡的目標上很有效。 / This thesis investigates the protocol design, testing, and diagnosis of Wireless Sensor Networks (WSNs) to achieve dependable WSNs. / In the aspect of protocol design, we focus on the MAC (Medium Access Control) layer protocol design. First, we propose an efficient MAC protocol RAS (routing and application based scheduling protocol) for underwater acoustic sensor networks (UWASNs), a type of WSNs that are deployed in the water. Utilizing the medium propagation difference between UWASNs and terrestrial wireless sensor networks (TWSNs), RAS performs parallel transmissions which would definitely result in collisions in TWSNs. It schedules the transmissions with different priorities by allocating longer time to heavier-traffic sensor nodes. The priority mechanism also benefits the fairness performance. Second, we tackle the unreliability problem caused by the packet loss in UWASNs. Based on the previously designed RAS, we propose a reliable RAS called RRAS that obtains a tradeoff between the reliability and the efficiency. RRAS applies an ACK and retransmission mechanism that is different from the traditional one, so that it can maintain a comparable throughput while improving reliability. / Third, in the area of protocol testing, we design RealProct (reliable Protocol conformance testing with Real sensor nodes), a novel and reliable framework for performing protocol conformance testing in WSNs, i.e., testing the protocol implementations against their specifications. With real sensor nodes, RealProct can ensure that the testing scenarios are as close to the real deployment as possible. To save the hardware cost and control efforts required by testing with large-scale real deployments, RealProct virtualizes a network with any topology and generates non-deterministic events using only a small number of sensor nodes. In addition, test execution and verdict are optimized to minimize the number of test case runs, while guaranteeing satisfactory false positive and false negative rates. / Finally, we propose MDiag, a Mobility-assisted Diagnosis approach that employs smartphones to patrol the WSNs and diagnose failures. Diagnosing with a smartphone which is not a component of WSNs does not intrude the execution of the WSNs as most of the existing diagnosis methods. Moreover, patrolling the smartphone in the WSNs to investigate failures is more efficient than deploying another diagnosis network. During the patrol, packets exchanged in the WSNs are collected and then analyzed by our implemented packet decoder. Statistical rules are also designed to guide the detection of abnormal cases. Aiming at improving the patrol efficiency, a patrol approach MSEP (maximum snooping efficiency patrol) is proposed. We compare MSEP with a naive method, the greedy method, and a baseline method, and demonstrate that MSEP is better in increasing the detection rate and reducing the patrol time than other methods. / We perform extensive evaluations to verify the proposed techniques and algorithms, and the results confirm their advantages in achieving dependable WSNs. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Xiong, Junjie. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 136-154). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract --- p.i / Acknowledgement --- p.iv / Chapter 1 --- Introduction and Background Study --- p.1 / Chapter 1.1 --- Wireless Sensor Networks (WSNs) --- p.1 / Chapter 1.1.1 --- Sensor Node --- p.5 / Chapter 1.1.2 --- The Base Station (BS) --- p.8 / Chapter 1.1.3 --- The Operating System (OS) of the Sensor Node --- p.8 / Chapter 1.1.4 --- The Protocol Design of WSNs --- p.11 / Chapter 1.2 --- Thesis Scope and Contributions --- p.20 / Chapter 1.2.1 --- Protocol Design --- p.20 / Chapter 1.2.2 --- Protocol Testing --- p.22 / Chapter 1.2.3 --- Protocol Diagnosis --- p.23 / Chapter 1.3 --- Thesis Organization --- p.23 / Chapter 2 --- An Efficient MAC Protocol Design --- p.25 / Chapter 2.1 --- Introduction --- p.26 / Chapter 2.2 --- Related Work --- p.28 / Chapter 2.3 --- RAS Overview --- p.29 / Chapter 2.3.1 --- Scheduling Element --- p.32 / Chapter 2.4 --- The Scheduling Problem in UWASNs --- p.34 / Chapter 2.4.1 --- Scheduling Principles --- p.34 / Chapter 2.4.2 --- Scheduling Problem Formulation --- p.35 / Chapter 2.4.3 --- Scheduling Problem Analysis --- p.37 / Chapter 2.5 --- RAS Protocol --- p.38 / Chapter 2.5.1 --- Scheduling Algorithm of the RAS Protocol --- p.38 / Chapter 2.5.2 --- Analysis of the RAS Protocol --- p.39 / Chapter 2.6 --- Performance Evaluation --- p.42 / Chapter 2.6.1 --- Schedule Length --- p.42 / Chapter 2.6.2 --- Network Throughput --- p.44 / Chapter 2.6.3 --- Average End-to-end Delay --- p.46 / Chapter 2.6.4 --- Average Maximum Queue Length per Node --- p.47 / Chapter 2.7 --- Discussions and Conclusions --- p.49 / Chapter 3 --- A Reliable MAC Protocol Design --- p.51 / Chapter 3.1 --- Introduction --- p.52 / Chapter 3.2 --- Related Work --- p.54 / Chapter 3.3 --- RRAS Protocol --- p.55 / Chapter 3.3.1 --- Overview of NACK-retransmission Mechanism --- p.56 / Chapter 3.3.2 --- Retransmission Mechanism --- p.57 / Chapter 3.3.3 --- Retransmission Time --- p.59 / Chapter 3.4 --- Performance Evaluation --- p.61 / Chapter 3.4.1 --- Retransmission Time of RRAS --- p.62 / Chapter 3.4.2 --- Working Time of RRAS and RAS --- p.63 / Chapter 3.4.3 --- Success Rate of RRAS and RAS --- p.64 / Chapter 3.4.4 --- Throughput of RRAS and RAS --- p.65 / Chapter 3.5 --- Conclusions --- p.66 / Chapter 4 --- Reliable Protocol Conformance Testing --- p.67 / Chapter 4.1 --- Introduction --- p.68 / Chapter 4.2 --- Related Work --- p.71 / Chapter 4.3 --- Protocol Conformance Testing --- p.73 / Chapter 4.3.1 --- PCT Process --- p.74 / Chapter 4.3.2 --- PCT Architecture --- p.75 / Chapter 4.4 --- Design of the RealProct Framework --- p.76 / Chapter 4.5 --- RealProct Techniques --- p.79 / Chapter 4.5.1 --- Topology Virtualization --- p.80 / Chapter 4.5.2 --- Event Virtualization --- p.81 / Chapter 4.5.3 --- Dynamic Test Execution --- p.85 / Chapter 4.6 --- Generality of RealProct --- p.88 / Chapter 4.7 --- Evaluation --- p.89 / Chapter 4.7.1 --- Detecting New Bugs in TCP --- p.90 / Chapter 4.7.2 --- Detecting Previous Bugs in TCP --- p.94 / Chapter 4.7.3 --- Testing Routing Protocol RMRP --- p.98 / Chapter 4.8 --- Conclusions --- p.99 / Chapter 5 --- Mobility-assisted Diagnosis for WSNs --- p.101 / Chapter 5.1 --- Introduction --- p.102 / Chapter 5.2 --- Related Work --- p.105 / Chapter 5.3 --- MDiag Background --- p.108 / Chapter 5.3.1 --- Network Architecture --- p.108 / Chapter 5.3.2 --- Failure Classification --- p.108 / Chapter 5.4 --- MDiag Framework --- p.109 / Chapter 5.4.1 --- Packet Decoder Input and Output --- p.111 / Chapter 5.4.2 --- Statistical Rules on Packet Analysis --- p.112 / Chapter 5.5 --- Coverage-oriented Smartphone Patrol Algorithms --- p.115 / Chapter 5.5.1 --- Naive Method (NM) --- p.115 / Chapter 5.5.2 --- Greedy Method (GM) --- p.116 / Chapter 5.5.3 --- Maximum Snooping Efficiency Patrol (MSEP) --- p.118 / Chapter 5.6 --- Evaluations --- p.119 / Chapter 5.6.1 --- Permanent Failure Detection --- p.121 / Chapter 5.6.2 --- Short-term Failure Detection --- p.122 / Chapter 5.7 --- Conclusions --- p.130 / Chapter 6 --- Conclusions --- p.132 / Bibliography --- p.136

published_or_final_version / abstract / Electrical and Electronic Engineering / Master / Master of Philosophy

Recent advances in Micro Electro-Mechanical Systems technology, wireless communications, and digital electronics have enabled the development of low-cost, low-power, multifunctional sensor nodes that are small in size and communicate untethered in short distances. These tiny sensor nodes, which consist of sensing, data processing, and communicating components, leverage the idea of sensor networks based on collaborative effort of a large number of nodes. A wide range of applications utilizing low-end sensor nodes to collaborative work together is envisioned for sensor networks. Some of the application areas are health, military, and security. For example, sensor networks can be used to detect foreign chemical agents in the air and the water. They can help to identify the type, concentration, and location of pollutants. In essence, sensor networks will provide the end user with intelligence and a better understanding of the environment. Realization of these and other sensor network applications require certain fundamental protocols and schemes. The objective of this thesis is to provide some of the basic building blocks that are necessary for sensor networks. These basic blocks are in the areas of routing, time synchronization, and localization. The routing protocol allows different types of traffics to be delivered and fused during delivery to lower the amount of information exchange. The time synchronization protocol enables the sensor nodes to maintain a similar time while the localization technique provides a way to find the sensor nodes in the sensor field. The routing, time synchronization, and localization schemes may be used to provide Quality-of-Service when data is gathered from the sensor networks.

A Wireless Sensor Network (WSN) is composed of a large number of sensor nodes that are densely deployed in an area. One of the main issues addressed in WSNs research is energy efficiency due to sensors' limited energy resources. WSNs are deployed to monitor and control the physical environment, and to transmit the collected data to one or more sinks using multi-hop communication. Energy efficiency protocols represent a key mechanism in WSNs. This dissertation proposes several methods used to prolong WSNs lifetime focusing on designing energy efficient communication protocols. A critical issue for data gathering in WSNs is the formation of energy holes near the sinks where sensor nodes participate more in relaying data on behalf of other sensors. The solution proposed in this dissertation is to use mobile sinks that change their location to overcome the formation of energy holes. First, a study of the improvement in network lifetime when sinks move along the perimeter of a hexagonal tiling is conveyed. Second, a design of a distributed and localized algorithm used by sinks to decide their next move is proposed. Two extensions of the distributed algorithm, coverage and time-delivery requirement, are also addressed. Sensor scheduling mechanisms are used to increase network lifetime by sending redundant sensor nodes to sleep. In this dissertation a localized connected dominating set based approach is used to optimize network lifetime of a composite event detection application. A set of active nodes form a connected set that monitor the environment and send data to sinks. After some time, a new active nodes set is chosen. Thus, network lifetime is prolonged by alternating the active sensors. QoS is another main issue encountered in WSNs because of the dynamically changing network topology. / This dissertation introduces an energy efficient QoS based routing for periodic and event-based reporting applications. A geographic routing mechanism combined with QoS support is used to forward packets in the network. Congestion control is achieved by using a ring or barrier mechanism that captures and aggregates messages that report the same event to the same sink. The main operations of the barrier mechanism are presented in this dissertation. / by Mirela Ioana Fonoage. / Vita. / Thesis (Ph.D.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

Sensors are shaping many activities in our society with an endless array of potential applications in military, civilian, and medical application. They support different real world applications ranging from common household appliances to complex systems. Technological advancement has enabled sensors to be used in medical applications, wherein they are deployed to monitor patients and assist disabled patients. Sensors have been invaluable in saving lives, be it a soldier's life in a remote battlefield or a civilian's life in a disaster area or natural calamities. In every application the sensors are deployed in a pre-defined manner to perform a specific function. Understanding the basic structure of a sensor node is essential as this would be helpful in using the sensors in devices and environments that have not been explored. In this research, patterns are used to present a more abstract view of the structure and architecture of sensor nodes and wireless sensor networks. This would help an application designer to choose from different types of sensor nodes and sensor network architectures for applications such as robotic landmine detection or remote patient monitoring systems. Moreover, it would also help the network designer to reuse, combine or modify the architectures to suit more complex needs. More importantly, they can be integrated with complete IT applications. One of the important applications of wireless sensor networks in the medical field is a remote patient monitoring system. In this work, patterns were developed to describe the architecture of patient monitoring system. / This pattern describes how to connect sensor nodes and other wireless devices with each other to form a network that aims to monitor the vital signs of a person and report it to a central system. This central system could be accessed by the patient's healthcare provider for treatment purposes. This system shows one of the most important applications of sensors and it application which needs to be integrated with medical records and the use of patterns makes this integration much simpler. / by Anupama Sahu. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

Zhou Yangfan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 102-112). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.v / Chapter 1 --- Introduction and Background Study --- p.1 / Chapter 1.1 --- Wireless Sensor Networks --- p.1 / Chapter 1.1.1 --- Wireless Integrated Network Sensors --- p.1 / Chapter 1.1.2 --- Main Challenge of In-situ Sensing with Sensor Nodes: Limited Energy Resource --- p.3 / Chapter 1.1.3 --- Networking the Sensor Nodes --- p.4 / Chapter 1.2 --- Applications of Wireless Sensor Networks --- p.4 / Chapter 1.3 --- Characteristics of Wireless Sensor Networks: A Summary --- p.6 / Chapter 1.4 --- Energy-Efficient and Reliable Wireless Sensor Networks --- p.9 / Chapter 2 --- PORT: A Price-Oriented Reliable Transport Protocol --- p.12 / Chapter 2.1 --- Reliable Sensor-to-Sink Data Communications in Wireless Sensor Networks --- p.14 / Chapter 2.2 --- Related Work --- p.17 / Chapter 2.3 --- Protocol Requirements --- p.20 / Chapter 2.4 --- Design Considerations --- p.25 / Chapter 2.4.1 --- The concept of node price --- p.25 / Chapter 2.4.2 --- Link-loss rate estimation --- p.28 / Chapter 2.4.3 --- Routing scheme --- p.29 / Chapter 2.5 --- Protocol Description --- p.31 / Chapter 2.5.1 --- Task initialization --- p.31 / Chapter 2.5.2 --- Feedback of newly desired source reporting rates --- p.32 / Chapter 2.5.3 --- Feedback of wireless communication condition --- p.32 / Chapter 2.5.4 --- Fault tolerance and scalability considerations --- p.33 / Chapter 2.6 --- Protocol Evaluation: A Case Study --- p.34 / Chapter 2.6.1 --- Simulation model --- p.34 / Chapter 2.6.2 --- Energy consumption comparison --- p.36 / Chapter 2.6.3 --- The impact of reporting sensors' uncertainty distribution --- p.39 / Chapter 2.7 --- Conclusion --- p.40 / Chapter 3 --- Setting Up Energy-Efficient Paths --- p.41 / Chapter 3.1 --- Transmitter Power Setting for Energy-Efficient Sensor-to-Sink Data Communications --- p.46 / Chapter 3.1.1 --- "Network, communication, and energy consumption models" --- p.46 / Chapter 3.1.2 --- Transmitter power setting problem for energy-efficient sensor-to-sink data communications --- p.49 / Chapter 3.2 --- Setting Up the Transmitter Power Levels for Sensor-to-Sink Traffic --- p.51 / Chapter 3.2.1 --- BOU: the basic algorithm --- p.52 / Chapter 3.2.2 --- Packet implosion of BOU: the challenge --- p.53 / Chapter 3.2.3 --- Determining the waiting time before broadcasting --- p.56 / Chapter 3.2.4 --- BOU-WA: an approximation approach --- p.60 / Chapter 3.3 --- Simulation Results --- p.62 / Chapter 3.3.1 --- The comparisons of BOU and BOU-WA --- p.63 / Chapter 3.3.2 --- The approximation of BOU-WA --- p.65 / Chapter 3.4 --- Related Work --- p.67 / Chapter 3.5 --- Conclusion Remarks and Future Work --- p.69 / Chapter 4 --- Solving the Sensor-Grouping Problem --- p.71 / Chapter 4.1 --- Introduction --- p.73 / Chapter 4.2 --- The Normalized Minimum Distance i:A Point-Distribution Index --- p.74 / Chapter 4.3 --- The Sensor-Grouping Problem --- p.77 / Chapter 4.3.1 --- Problem Formulation --- p.80 / Chapter 4.3.2 --- A General Sensing Model --- p.81 / Chapter 4.4 --- Maximizing-i Node-Deduction Algorithm for Sensor-Grouping Problem --- p.84 / Chapter 4.4.1 --- Maximizing-i Node-Deduction Algorithm --- p.84 / Chapter 4.4.2 --- Incremental Coverage Quality Algorithm: A Benchmark for MIND --- p.86 / Chapter 4.5 --- Simulation Results --- p.87 / Chapter 4.5.1 --- Number of Groups Formed by MIND and ICQA --- p.88 / Chapter 4.5.2 --- The Performance of the Resulting Groups --- p.89 / Chapter 4.6 --- Conclusion --- p.90 / Chapter 5 --- Conclusion --- p.92 / Chapter A --- List of Research Conducted --- p.96 / Chapter B --- Algorithms in Chapter 3 and Chapter 4 --- p.98 / Bibliography --- p.102

近年來感測器、集成電路及無線通信的科技迅速發展，促使IEEE802.15工作小組6（TG6）致力硏究一個新的無線通信標準─人體區域網路（BAN）。這個新標準特別考量在人體上、人體內或人體周邊的應用。雖然BAN至今還未達成最後定案，不同類型的應用方案已被廣泛提出。這些方案可分為醫療應用（例如：生命徵象感測和植入式治療）及非醫療應用（例如：消費性電子、個人娛樂和遙遠控制）。無線感測節點〈WSN）的基本要求包括輕巧、廉價及低耗電量。因此，本論文提出了一個符合以上要求的注入式鎖態發射機。此外，我們設計了三個發射機的內部模組。由於BAN的物理層例如調變方式和頻譜配置還未完全製訂，本文的電路設計將基於IEEE802.15 TG6的初步建議。 / 第一個模組是一個利用同相位雙路輸入及電流再使用技術的次毫瓦、第一次諧波LC注入式鎖態振盪器〈ILO）。該振盪器操作範圍在醫療植入式通訊服務〈MICS）頻段，並已採用了0.13-μm CMOS工藝實現而僅佔有200 m x 380 m芯片面積。實驗結果表明，在輸入動力0 dBm時，其鎖定範圍可達800 MHz (150 950 MHz) 。最重要的是，該ILO擁有-30 dBm的高輸入靈敏度，同時在1-V供電下只消耗660 A靜態電流。超低的靜態電流使WSN能從人體收集能量而變得完全自主。 / 第二個模組是一個低功耗MICS非整數型頻率合成器，其目的在於選擇信道。雖然整數鎖相環由於其低複雜性而被廣泛使用，對MICS頻段而言並不是一項良好方案。主要原因在於其信道寬只有300 kHz，速度、頻率解析度和相位雜訊變得很難平衡。為此，我們採用0.13-μm CMOS製程設計了一個4階第二型和差積分〈Σ-）調變器分數鎖相環。為了抑制混附單頻信號，二階單迴路數字Σ-調變器加入了抖動。仿真結果顯示該頻率合成器能在15 s內鎖定，同時在1.5-V供電下只消耗4 mW功耗。 / 第三個模組是一個高效能、完全集成的E類功率放大器〈PA）。該PA採用了自給偏壓反相器作為前置放大器，操作範圍在MICS頻段及工業、科學和醫學〈ISM）頻段。在0.18-m CMOS工藝下實現的該PA佔有0.9 mm x 0.7 mm芯片面積。實驗結果表明，在1.2-V供電下及操作頻率是433 MHz時，該PA的漏極效率及輸出功率分別可達40.2 %和14.7 dBm。當操作頻率從380 MHz 到460 MHz，該PA仍能保侍最少34.7 %的漏極效率。此設計適用於低數據傳輸率、固定振幅調變，例如：QPSK、OQPSK等。 / Recent technological advances in sensors, integrated circuits and wireless communication enable miniature devices located on, in or around the human body to form a new wireless communication standard called wireless Body Area Network (BAN). Although BAN is still being investigated by the IEEE 802.15 Task Group 6 (TG6), a vast variety of applications has been proposed which can be categorized into medical applications (e.g. vital signs monitoring and implantable therapeutic treatment) and non-medical applications (e.g. consumer electronics and remote control). The basic requirements of each Wireless Sensor Node (WSN) include light weight, small form-factor, low cost and low power consumption. This thesis proposes an injection-locked transmitter which is a potential candidate to minimize the power consumption of the RF transmitter in WSNs. Three circuit blocks in the proposed injection-locked transmitter are designed and implemented. Since the physical layer of BAN, such as modulation scheme and frequency allocation, has still not been finalized yet, the prototypes in this thesis are designed based on the preliminary suggestions made by the IEEE 802.15 TG6. / The first circuit block is a sub-mW, current-reused first-harmonic LC injection-locked oscillator (ILO) using in-phase dual-input injection technique, operating in the Medical Implantable Communications Service (MICS) band from 402MHz to 405 MHz for medical implants. It has been fabricated in a standard 0.13-m CMOS technology; occupying 200 m x 380 m. Measurement results show that the proposed ILO features a wide locking range of 800 MHz (150-950 MHz) at input power of 0 dBm. More importantly, it has a high input sensitivity of -30 dBm to lock the 3-MHz bandwidth of the MICS band, while consuming only 660 W at 1-V supply. This ultra-low power consumption enables autonomous WSNs by energy harvested from the human body. / The second circuit block is a low power MICS fractional-N frequency synthesizer for channel selection. Although integer-N phase-locked loop (PLL) is widely used due to its low circuit complexity, it is not considered as a good solution for MICS band where the channel spacing is just 300 kHz, due to the severe trade-off between speed, frequency resolution and phase noise performance. To solve this issue, a 4th-order type-II Σ- fractional-N PLL is designed using a standard 0.18-m CMOS technology. A 2nd-order single-loop digital Σ- modulator with dither is designed to eliminate the spurious tones. Simulation results verify that the synthesizer achieves 15 s locking time and consumes 4 mW at a power supply of 1.5 V. / Finally, a power-efficient fully-integrated class-E power amplifier with a self-biased inverter used as a preamplifier stage has been implemented in a standard 0.18-m CMOS process, with 0.9 mm x 0.7 mm active area. It operates in both MICS band for implantable devices and Industrial, Scientific and Medical (ISM) band for wearable devices. Experimental results shows that it achieves 40.2 % drain efficiency while output power is 14.7 dBm at 433 MHz under 1.2-V supply. Moreover, the drain efficiency maintains at least 34.7 % over the frequency range from 380 MHz to 460 MHz. This design is suitable for low data-rate, constant envelope modulation, such as QPSK, OQPSK, etc. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Kwan Wai. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract of thesis entitled: --- p.I / 摘要 --- p.IV / Contents --- p.VI / List of Figures --- p.XI / List of Tables --- p.XVII / Acknowledgement --- p.XVIII / Chapter CHAPTER 1. --- Introduction --- p.1 / Chapter 1.1 --- Motivation for body area network (BAN) --- p.1 / Chapter 1.2 --- Standardization of BAN and its positioning between different communication technologies --- p.3 / Chapter 1.3 --- Classification of BAN and its potential applications --- p.5 / Chapter 1.4 --- Requirements and challenges of BAN --- p.7 / Chapter 1.5 --- Research objectives and organization of this dissertation --- p.9 / References --- p.11 / Chapter CHAPTER 2. --- Background information of biomedical transceivers --- p.12 / Chapter 2.1 --- MICS band --- p.12 / Chapter 2.1.1 --- Frequency allocation --- p.12 / Chapter 2.1.2 --- Output power --- p.13 / Chapter 2.1.3 --- Transmit spectral mask --- p.14 / Chapter 2.1.4 --- Transmit center frequency tolerance --- p.14 / Chapter 2.1.5 --- Channel model --- p.15 / Chapter 2.1.6 --- Link budget --- p.17 / Chapter 2.2 --- Fundamental figure of merits for transceivers --- p.18 / Chapter 2.2.1 --- Noise figure, noise floor and receiver sensitivity --- p.18 / Chapter 2.2.2 --- Transmitter energy efficiency --- p.19 / References --- p.20 / Chapter CHAPTER 3. --- Review of transmitter architectures --- p.21 / Chapter 3.1 --- Overview --- p.21 / Chapter 3.2 --- Architectures --- p.22 / Chapter 3.2.1 --- Quadrature --- p.22 / Chapter 3.2.2 --- Polar --- p.23 / Chapter 3.2.3 --- PLL-based --- p.24 / Chapter 3.2.4 --- Injection-locked --- p.26 / Chapter 3.3 --- Radio architecture selection for biomedical systems in BAN --- p.27 / Chapter 3.3.1 --- Data-rate --- p.27 / Chapter 3.3.2 --- Modulation scheme --- p.28 / Chapter 3.3.3 --- Proposed transmitter architecture --- p.28 / References --- p.31 / Chapter CHAPTER 4. --- Design of sub-mW injection-locked oscillator --- p.33 / Chapter 4.1 --- Introduction --- p.34 / Chapter 4.2 --- Circuit design and analysis --- p.34 / Chapter 4.3 --- Experimental results --- p.47 / Chapter 4.4 --- Summary --- p.55 / References --- p.56 / Chapter CHAPTER 5. --- Design of low-power fractional-N frequency synthesizer --- p.58 / Chapter 5.1 --- Synthesizer architectures --- p.59 / Chapter 5.2 --- PLL design fundamentals --- p.63 / Chapter 5.2.1 --- Stability --- p.63 / Chapter 5.2.2 --- Phase noise --- p.65 / Chapter 5.3 --- Proposed architecture --- p.67 / Chapter 5.4 --- System design --- p.68 / Chapter 5.4.1 --- Stability --- p.68 / Chapter 5.4.2 --- Phase noise --- p.73 / Chapter 5.5 --- Σ modulation in fractional-N synthesis --- p.75 / Chapter 5.5.1 --- Basic operating principles --- p.76 / Chapter 5.5.2 --- An accumulator as a first-order Σ- modulator --- p.78 / Chapter 5.5.3 --- Noise analysis --- p.80 / Chapter 5.5.4 --- Architectures --- p.84 / Chapter 5.5.5 --- Design and modeling --- p.87 / Chapter 5.5.6 --- Digital circuit implementation --- p.99 / Chapter 5.5.7 --- Measurement results --- p.104 / Chapter 5.6 --- Time domain behavioral modeling --- p.104 / Chapter 5.7 --- Design of building blocks --- p.106 / Chapter 5.7.1 --- VCO --- p.107 / Chapter 5.7.1.1 --- Principles --- p.107 / Chapter 5.7.1.2 --- Circuit design --- p.111 / Chapter 5.7.2 --- PFD --- p.131 / Chapter 5.7.2.1 --- Principles --- p.131 / Chapter 5.7.2.2 --- Circuit design --- p.133 / Chapter 5.7.3 --- CP --- p.136 / Chapter 5.7.3.1 --- Principles --- p.136 / Chapter 5.7.3.2 --- Circuit design --- p.137 / Chapter 5.7.4 --- Frequency divider --- p.138 / Chapter 5.7.4.1 --- Principles --- p.138 / Chapter 5.7.4.2 --- Circuit design --- p.145 / Chapter 5.7.5 --- Loop filter --- p.148 / Chapter 5.8 --- Layout issues --- p.149 / Chapter 5.9 --- Overall simulation results --- p.150 / Chapter 5.1 --- Summary --- p.152 / References --- p.153 / Chapter CHAPTER 6. --- Design of high-efficient power amplifier --- p.154 / Chapter 6.1 --- Classification of PAs --- p.154 / Chapter 6.2 --- Circuit design considerations --- p.158 / Chapter 6.3 --- Experimental results --- p.160 / Chapter 6.4 --- Summary --- p.164 / References --- p.166 / Chapter CHAPTER 7. --- Conclusions and future work --- p.167 / Chapter 7.1 --- Conclusions --- p.167 / Chapter 7.2 --- Future work --- p.168 / References --- p.171

Surface acoustic wave (SAW) devices are a solution for today’s ever growing need for passive wireless sensors. Orthogonal frequency coding (OFC) together with time division multiplexing (TDM) provides a large number of codes and coding algorithms producing devices that have excellent collision properties. Novel SAW noise-like re- flector (NLR) structures with pulse position modulation (PPM) are shown to exhibit good auto- and cross-correlation, and anti-collision properties. Multi-track, multi-transducer approaches yield devices with adjustable input impedances and enhanced collision properties for OFC TDM SAW sensor devices. Each track-transducer is designed for optimum performance for loss, coding, and chip reflectivity. Experimental results and theoretical predictions confirm a constant Q for SAW transducers for a given operational bandwidth, independent of device and transducer embodiment. Results on these new NLR SAW structures and devices along with a new novel 915 MHz transceiver based on a software radio approach was designed, built, and analyzed. Passive wireless SAW temperature sensors were interrogated and demodulated in a spread spectrum correlator system using a new adaptive filter. The first-ever SAW OFC four-sensor operation was demonstrated at a distance of 1 meter and a single sensor was shown to operate up to 3 meters. Comments on future work and directions are also presented

A Wireless Sensor Network (WSN) is composed of low-cost electronic devices with sensing, data storage and transmitting capabilities, powered by batteries. There are extensive studies in the field of WSN investigating different algorithms and protocols for data collection. A data collector can be static or mobile. Using a mobile data collector can extend network lifetime and can be used to collect sensor data in hardly accessible locations, partitioned networks, and delay-tolerant networks. The implementation of the mobile data collector in our study consists of combining two different platforms: the Crossbow sensor hardware and the NXT Legos. We developed an application for data collection and sensor querying support. Another important contribution is designing a semi-autonomous robot control. This hardware prototype implementation shows the benefits of using a mobile data collector in WSN. It also serves as a reference in developing future applications for mobile WSNs. / by Pedro L. Heshike. / Thesis (M.S.C.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.

Sensors are used to monitor and control the physical environment. A Wireless Sen- sor Network (WSN) is composed of a large number of sensor nodes that are densely deployed either inside the phenomenon or very close to it [18][5]. Sensor nodes measure various parameters of the environment and transmit data collected to one or more sinks, using hop-by-hop communication. Once a sink receives sensed data, it processes and forwards it to the users. Sensors are usually battery powered and it is hard to recharge them. It will take a limited time before they deplete their energy and become unfunctional. Optimizing energy consumption to prolong network lifetime is an important issue in wireless sensor networks. In mobile sensor networks, sensors can self-propel via springs [14], wheels [20], or they can be attached to transporters, such as robots [20] and vehicles [36]. In static sensor networks with uniform deployment (uniform density), sensors closest to the sink will die first, which will cause uneven energy consumption and limitation of network life- time. In the dissertation, the nonuniform density is studied and analyzed so that the energy consumption within the monitored area is balanced and the network lifetime is prolonged. Several mechanisms are proposed to relocate the sensors after the initial deployment to achieve the desired density while minimizing the total moving cost. Using mobile relays for data gathering is another energy efficient approach. Mobile sensors can be used as ferries, which carry data to the sink for static sensors so that expensive multi-hop communication and long distance communication are reduced. In this thesis, we propose a mobile relay based routing protocol that considers both energy efficiency and data delivery delay. It can be applied to both event-based reporting and periodical report applications. / Another mechanism used to prolong network lifetime is sensor scheduling. One of the major components that consume energy is the radio. One method to conserve energy is to put sensors to sleep mode when they are not actively participating in sensing or data relaying. This dissertation studies sensor scheduling mechanisms for composite event detection. It chooses a set of active sensors to perform sensing and data relaying, and all other sensors go to sleep to save energy. After some time, another set of active sensors is chosen. Thus sensors work alternatively to prolong network lifetime. / by Yinying Yang. / Vita. / Thesis (Ph.D.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.