Wireless Sensor Networks

Transcription

1 Edgar H. Callaway, Jr. Wireless Sensor Networks Architectures and Protocols A AUERBACH PUBLICATIONS A CRC Press Company Boca Raton London New York Washington, D.C.

2 Chapter 1 Introduction to Wireless Sensor Networks Applications and Motivation Industrial Control and Monitoring Home Automation and Consumer Electronics Security and Military Sensing Asset Tracking and Supply Chain Management Intelligent Agriculture and Environmental Sensing Health Monitoring Network Performance Objectives Low Power Consumption Low Cost Worldwide Availability Network Type Security Data Throughput Message Latency Mobility Contributions of this Book Organization of this Book 17 References 17 Chapter 2 The Development of Wireless Sensor Networks Early Wireless Networks Wireless Data Networks The ALOHA System The PRNET System Amateur Packet Radio Networks Wireless Local Area Networks (WLANs) Wireless Personal Area Networks (WPANs) Wireless Sensor and Related Networks WINS 33

3 2.3.2 PicoRadio uamps Terminodes, MANET, and Other Mobile Ad Hoc Networks Underwater Acoustic and Deep Space Networks Conclusion 35 References 36 Chapter 3 The Physical Layer Introduction Some Physical Layer Examples Bluetooth IEEE b Wireless Sensor Networks PicoRadio WINS (lamps A Practical Physical Layer For Wireless Sensor Networks Cost Power Power Source Power Consumption Simulations and Results Simulations Results Conclusion 59 References 59 Chapter 4 The Data Link Layer, Introduction Medium Access Control Techniques ALOHA Carrier Sense Multiple Access (CSMA) Polling Access Techniques in Wireless Sensor Networks WINS PicoRadio Others The Mediation Device (MD) The MD Protocol The Distributed MD Protocol "Emergency" Mode Channel Access System Analysis and Simulation Duty Cycle 78 viii

4 4.4.2 Latency Conclusion 81 References 82 Chapter 5 The Network Layer Introduction Some Network Design Examples Structure Routing A Wireless Sensor Network Design Employing a Cluster Tree Architecture Network Design Network Association Network Maintenance Routing Simulations Results Throughput (Cumulative Percentage of Messages Arriving at the DD versus Time) Throughput (Cumulative Percentage of Messages Arriving at the DD versus Node Level) Average Message Transmission Time Average Message Latency versus Node Level Packet Collisions versus Time Duty Cycle Duty Cycle versus Level Message Latency versus MD Period Maximum Network Throughput versus MD Period Maximum Network Throughput versus Node Density Conclusion 110 References 110 Chapter 6 Practical Implementation Issues Introduction The Partitioning Decision Transducer Interfaces Integrated Sensors The External Interface Time Base Accuracy and Average Power Consumption Conclusion 135 References 135 Chapter 7 Power Management Introduction Power Sources 138 ix

5 7.2.1 Mains Batteries Lifetime "Low Battery" Detection "Low Battery" Alarm Choice of Cell Chemistry Energy Scavenging Photovoltaic Cells Mechanical Vibration Other Scavengable Energy Sources Loads Power Consumption of Analog Circuits Power Consumption of Digital Logic Power Consumption of Other Loads Voltage Converters and Regulators Types of Voltage Converters Voltage Conversion Strategy Power Management Strategy Conclusion 185 References 186 Chapter 8 Antennas and the Definition of RF Performance Introduction Antennas Antenna Characteristics Efficiency and Antenna Placement Bandwidth Antenna Design Choices RF Performance Definition and Measurement Definition and Measurement Production Issues Conclusion 215 References 216 Chapter 9 Electromagnetic Compatibility Introduction EMC: The Problem Examples of Self-Interference The Physics Associated with EMC Problems The Wideband Spectral View The Narrowband Spectral View Victim Circuits in Receivers The Zero-IF Receiver The Low-IF Receiver The Superheterodyne Receiver 235 x

6 9.4.4 Scope of the Problem Digital-RF Isolation Needed Coupling Mechanisms "Radiated" Coupling "Conducted" Coupling Avoiding Coupling Problems System Level Integrated Circuit Level Circuit Board Level Principles of Proper Layout There is No Ground There is Only Return Current The Layout Process Things to Look for After the Schematics Are Done but Before the Layouts Are Started High-Frequency Voltages and Currents Antenna Placement Power Source Placement Sensor Placement Placement of Oscillators RF Filters, Low-Noise Amplifiers (LNAs), and Power Amplifiers EMC-Aware Layout Procedure Detective/Corrective Techniques The "Hole in the Bucket" Principle Substitution Software to Control Specific MCU Functions Physical Separation The Fallacy of Shields Get to Know the IC Designer Simulation Conclusion 266 References 266 Chapter 10 Electrostatic Discharge Introduction The Problem Examples Failure Modes Physical Properties of the Electrostatic Discharge The Triboelectric Effect Air Breakdown Charge Redistribution The Effects of ESD on ICs Modeling and Test Standards 276 xi

7 The Double Exponential Pulse Human Body, Machine, and Charged Device Models Detailed Requirements of an ESD Standard Performance Standards Product Design to Minimize ESD Problems Prevent Discharges from Entering or Exiting the Housing Avoid Holes in the Housing Locate Circuit Boards and the Metal on Them Away from Housing Holes Eliminate Metal Points and Burrs Once Inside, Design Paths for the Discharge to Travel Reaching the Integrated Circuit Once an ESD Event Occurs, Limit Discernable Effects Conclusion 290 References 291 Chapter 11 Wireless Sensor Network Standards Introduction The IEEE Low-Rate WPAN Standard The ZigBee Alliance The IEEE Wireless Smart Transducer Interface Standard 298 References 299 Chapter 12 Summary and Opportunities for Future Development Summary Opportunities for Future Development 304 References 307 Appendix A Signal Processing Worksystem (SPW) 309 Appendix B WinneuRFon 311 B.I Introduction 311 B.2 Motivation 311 B.3 System Requirements 312 B.4 Supported Features 313 B.5 Current Status and Achievement 313 B.6 Simulation Method and More Potential Functionalities 316 B.7 Proposal for Future Work 318 B.8 Summary 318 Appendix C An Example Wireless Sensor Network Transceiver Integrated Circuit (IQ 319

8 About the Author 325 Index 327 Xlll