Preface

A Wireless Sensor Network (WSN) represents the next technological revolution which distinguishes from other wireless or wired networks through its capability of interaction with the environment. This network has been proposed for various applications including monitoring the environment, home and business smart environments, better management of cities in areas like traffic control, intelligent transportation, search and rescue, disaster relief, and localization systems. These applications require a large amount of battery-powered wireless sensors, and are usually designed for long-term deployments with no human intervention. Subsequently, energy efficiency is one of the main design objectives for these sensor networks. This book offers the basics as well as advanced research materials for wireless sensor networks.

Chapter 1 deals with the proper node placement in the monitored field to ensure good sensing coverage and communication connectivity. It presents and analyzes four specific ways that nodes can be placed on a grid and compares the performance of congestion control algorithms under these placements.

Chapter 2 attempts various possible approaches that designers might adopt in order to provide energy efficient WSN. Some approaches offer to define a trade-off between opposing aims, such as QoS and energy consumption. Each approach presented in this Chapter is aiming at solving at least one identified cause of extensive energy consumption. The approaches are using the WSN's different design levels to increase the network's lifetime, QoS, and/or optimize other points that may or may not suit the designer.

Chapter 3 examines a radio-triggered wake-up circuit and explores its application in the power management of the WSNs. It should be mentioned that the radio-triggered wake-up circuit can be used in other applications, such as the synchronization of the WSNs.

Chapter 4 designs some MAC solutions to deal with real time applications in WSNs where mobile nodes are implemented in the network. WSN MAC protocols are application dependent and focus on energy consumption and transmission latency.

#### XII Preface

Chapter 5 explains how the cluster-tree structure impacts the network capacity and the energy Consumption. This chapter also presents a localized algorithm to find autonomously accurate parameters values, to operate always around the optimal situation.

Chapter 6 deals with the problem of reliability modelling with wireless sensor network (WSN), which is rapidly becoming a platform for applications including antiterrorism, smart spaces, numerous military sensing and command and control applications, and entertainment. Inherent in these safety-critical applications is a priority and urgency of the information or messages. To the best of the authors' knowledge, there is no systematical research done so far to unify energy consume and message delay into reliability modelling for WSN. The work in this chapter differs from the previous work in that it proposes a model of the system and an integrated model of the task which consider energy consume and message delay for the safetycritical application, introduces both the energy factor function and time factor function, and also establishes an integrated reliability model of WSN based on a task. The illustration of modelling suggests that the method studied has a directive influence to both task division and topology selection of WSN system.

Chapter 7 introduces a framework for integrating WSNs and the Internet at service level, by allowing the interoperability of their services.

Chapter 8 presents data reduction process in WSN which is a challenging task as data exists in the form of continuous stream (infinitely large data set) where the adaptation and prediction has to be performed online i.e. at a given instance of time not all the information is available for processing. Typically, the spatial and temporal relations among the data sources in WSN are exploited to achieve fair data reduction rates. In essence, it can be said that data reduction is one of the most effective ways to conserve energy in Wireless Sensor Networks.

Chapter 9 presents computationally low power, low bandwidth, and low cost filters that will remove the noise and compress the data so that a decision can be made at the node level.

Chapter 10 presents clustering scheme which is based on selecting the node that reduces the packet size among all the active nodes in the system. The sink selects the node which minimizes the total amount of data as a cluster head (CH), therefore increasing the efficiency of the compression technique by sending only the difference, rather than the complete data value, to the CH.

Chapter 11 focuses on some of the main concerns for design in mission-critical monitoring application scenarios, and brings forward efficient methods and solutions according to network connectivity, dynamic application scenarios. Major research challenges and open research issues in mission-critical monitoring applications of WSNs are also outlined.

Chapter 12 outlines the design, optimization and development of a practical solution for application to the Cultural Heritage monitoring and control. The overall system was addressed in terms of the experiences platform, network issues related both to the node's communication protocol and gateway operations up to the remote user's suitable interface. In particular, the presented solution is installed in several museums and it is used to monitor the art objects during their transport from a museum to another. The experimental results highlight a noticeable performance as far as the data collecting reliability, the system robustness and the usability are involved.

X Preface

situation.

Chapter 5 explains how the cluster-tree structure impacts the network capacity and the energy Consumption. This chapter also presents a localized algorithm to find autonomously accurate parameters values, to operate always around the optimal

Chapter 6 deals with the problem of reliability modelling with wireless sensor network (WSN), which is rapidly becoming a platform for applications including antiterrorism, smart spaces, numerous military sensing and command and control applications, and entertainment. Inherent in these safety-critical applications is a priority and urgency of the information or messages. To the best of the authors' knowledge, there is no systematical research done so far to unify energy consume and message delay into reliability modelling for WSN. The work in this chapter differs from the previous work in that it proposes a model of the system and an integrated model of the task which consider energy consume and message delay for the safetycritical application, introduces both the energy factor function and time factor function, and also establishes an integrated reliability model of WSN based on a task. The illustration of modelling suggests that the method studied has a directive

Chapter 7 introduces a framework for integrating WSNs and the Internet at service

Chapter 8 presents data reduction process in WSN which is a challenging task as data exists in the form of continuous stream (infinitely large data set) where the adaptation and prediction has to be performed online i.e. at a given instance of time not all the information is available for processing. Typically, the spatial and temporal relations among the data sources in WSN are exploited to achieve fair data reduction rates. In essence, it can be said that data reduction is one of the most effective ways to conserve

Chapter 9 presents computationally low power, low bandwidth, and low cost filters that will remove the noise and compress the data so that a decision can be made at the

Chapter 10 presents clustering scheme which is based on selecting the node that reduces the packet size among all the active nodes in the system. The sink selects the node which minimizes the total amount of data as a cluster head (CH), therefore increasing the efficiency of the compression technique by sending only the difference,

Chapter 11 focuses on some of the main concerns for design in mission-critical monitoring application scenarios, and brings forward efficient methods and solutions according to network connectivity, dynamic application scenarios. Major research challenges and open research issues in mission-critical monitoring applications of

influence to both task division and topology selection of WSN system.

level, by allowing the interoperability of their services.

energy in Wireless Sensor Networks.

rather than the complete data value, to the CH.

node level.

WSNs are also outlined.

Chapter 13 presents the application of wireless technologies to the shipboard monitoring system. A measurement campaign has been carried out on board a ferry to determine path loss models. Based on the measurement results and the particularities of the environment, a hierarchical zone-based architecture has been proposed for a large shipboard WSN.

Chapter 14 presents a monitoring system that is applied to underground power electrical substation. The system presented in this chapter allows choosing the desired communication transmission mode: wired, wireless, or both. Performance results show that our system could well be applied for monitoring and fault detection in electrical underground network grid systems.

Chapter 15 presents some solutions to certain road monitoring problems unresolved by several works presented in literature, in which streets monitoring are realized using cameras only. Cameras can produce several problems when weather conditions are not optimal (poor visibility, fog or heavy rain). Road monitoring and WSNs have been extensively explored in their respective domains, however, the combination of them has not been sufficiently studied until recent years. The challenge of this chapter is to advance the state of the art introducing an innovative approach that allows monitoring real-time road traffic and, at the same time, dynamically manages network topology and power consumption through a fuzzy based algorithm.

Chapter 16 introduces some control strategies and concepts from both traffic and control engineering point of view and provides some simulations to support the theoretical discussion.

I hope that this book will serve as a comprehensive reference for graduate students as well as senior undergraduate students and that it will be useful as a learning tool for research in this exciting field.

> **Mohamamd A. Matin** Institut Teknologi Brunei, Brunei Darussalam

**Design and Analysis for Deployment** 

**Chapter 0 Chapter 1**
