Clustering Algorithm to Prolong the Lifetime in Wireless Sensor Network

摘要

The Wireless Sensor Networks (WSNs) have become one of the active technologies and been exploited by the various applications.In WSNs, the data, which are sensed by the randomly distributed sensors, are transmitted to the Base Station (BS) where the data were further processed.A typical WSN usually consists of the randomly distributed sensors in the sensing field to monitor environmental conditions, such as temperature, sound, vibration, pressure, motion.The main challenge in the WSNs is the limited energy of the nodes.As an important strategy, the clustering algorithm can help the WSNs to prolong the network lifetime, provide recommendations to application developers and may optimize the energy consumption of the applications in the WSN.A simple efficient method to extend the network lifetime is discussed with the help of the Mobile Element (ME).The MEs act as the mechanical carriers, which move around in the sensing field, collect the data from the sensors and transmit the data to the BS.An energy-efficient mechanism to prolong the network lifetime is required.To address the problem of fast depletion of battery life, we design a clustering algorithm with considering the energy depletion speed.The main contributions of this dissertation including: 1) We investigate the clustering algorithm, design a new method for the cluster-head selection.2) We also set up the cluster according to K-means algorithm and suggest using the Beacon Node (BN) to prolong the network lifetime.3) Modification of LEACH-m to improve the disadvantages of the LEACH.4) The ME collects data from the CHs on the planned tour.With an effective cooperation between MEs and BN, the data will be uploaded to the sink.We conduct an extensive simulation.The results of the simulation show that compared with the LEACH and LEACH-m, the cluster algorithms with the MEs outperform that without the help of the MEs in terms of the network lifetime.

目录

声明

Abstract

Table of Contents

List of Figures

CHAPTER 1 INTRODUCTION

1．1 Background

1．2 The Technologies of WSNs

1．3 The Applications in WSNs

1．4 The Challenges in WSNs

1．5 The Motivations and Objectives

1．6 Overview of Data Collection in WSNs

1．6．1 The traditional data collection methods

1．6．2 The methods and benefits of the mobile data collection

1．7 Thesis organization

CHAPTER 2 RELATED WORK AND LITERATURE REVIEW

2．1 Introduction

2．2 The Clustering methods

2．3 The advantages of the modified LEACH

2．4 WSN with Mobile Elements

2．4．1 Relocatable Nodes

2．4．2 Mobile Data Collectors(MDCs)

2．4．3 Mobile Peers

2．5 Overview of the data collection methods in WSN-ME

2．6 Medium Access Control

2．7 Summary

CHAPTER 3 CLUSTERING AND CLUSTER HEAD SELECTION

3．1 Introduction

3．2 The Clustering methods in WSNs

3．2．1 The K-means Method

3．2．2 Cluster Setup

3．2．3 The selection of the Cluster Head

3．3 Multi-hop Routing

3．4 Summary

CHAPTER 4 ME-ASSISTED DATA COLLECTION SCHEME

4．1 Introduction

4．2 The selection of the Beacon Node

4．3 The Traverse Path Computation of ME

4．3．1 The Travelling Salesman Problem(TSP)

4．3．2 The Visiting Order in a Cluster

4．4 Data Collection from each visiting CH

4．5 Summary

CHAPTER 5 SIMULATIOM AND ANALYSIS

S．1 The model of the Cluster algorithm

5．2 Radio energy consumption model

5．3 Evaluation of the proposed algorithm

5．3．1 The ratio of the death node

5．3．2 The Network’s Lifetime

5．4 Analysis of residual energy

5．5 Summary

CHAPTER 6 CONCLUSTION AND FUTURE WORK

6．1 The summary of the Thesis

6．2 The future work

REFERENCES

ACKNOWLEDGEMENTS