Thesis of Takahiro Fujiwara

A Multihop Wireless Network Architecture for Disaster Communications

Abstract                                                                                                                    i

Acknowledgements                                                                                                   v

Contents                                                                                                                   vii

Chapter 1  Introduction                                                                                              1

Chapter 2  Related Works                                                                                         9

    2.1      Introduction                                                                                                  9

    2.2      Information System in a Disaster                                                                   9

    2.3      Current Wireless Networks                                                                          14

    2.4      Network Model for Disaster Communications                                               20

    2.5      Summary                                                                                                      22

Chapter 3  A Hierarchical Wireless Network for Disaster Communications                 23

    3.1      Introduction                                                                                                  23

    3.2      Network Model                                                                                           24

    3.3      System Design                                                                                              25

    3.4      Experimental System                                                                                    31

    3.5      Propagation Characteristics                                                                          33

    3.6      Interference of Wireless LAN                                                                       36

    3.7      Summary                                                                                                      45

Chapter 4  A Hybrid Wireless Network Enhanced with Ad hoc Networking              46

    4.1      Introduction                                                                                                  46

    4.2      Network Architecture for Disaster Communications                                      47

    4.3      Network Model of ECCA                                                                            49

    4.4      Channel Structure                                                                                         50

    4.5      Routing Protocol                                                                                          53

    4.6      Medium Access Control Protocol                                                                 69

    4.7      Scenario for Route Discovery and Multihopping                                            77

    4.8      Summary                                                                                                      79

Chapter 5  ECCA Wireless Network Performance                                                     80

    5.1      Introduction                                                                                                  80

    5.2      Setup for Experiments                                                                                  80

    5.3      Evaluation Results                                                                                         84

    5.4      Summary                                                                                                      94

Chapter 6  Discussion                                                                                                95

    6.1      Disaster Communications in Cellular System                                                  95

    6.2      Comparison with Multihop Cellular Systems                                                  96

    6.3      Applicability of ECCA for Damage Assessment                                            101

    6.4      Sensor Networks for Disaster Relief                                                             106

Chapter 7  Conclusion                                                                                               109

Appendix -A  An Analytical Model for ECCA Network                                           114

    A.1     Analytical Model with Markov                                                                      114

    A.2     Discussion                                                                                                    117

Bibliography                                                                                                               121

Author's Bibliography                                                                                                 132