Wireless sensor Network Text Book: Kazim Shorbay Chapter 1

1. Wireless Sensor Networks
Prepared By: Dr. Nagarathna and Deepika
Dept. of CS & E
PESCE, Mandya
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2. APPLICATIONS OF WIRELESS
SENSOR NETWORKS
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3. Introduction
• WSNs are collections of compact-size ,relatively inexpensive
computational nodes that measure local environmental
conditions or other parameters and forward such information
to a central point for appropriate processing.
• WSNs nodes(WNs) can sense the environment ,can
communicate with neighboring nodes, and can ,in many
cases, perform basic computations on the data being
collected.
• WSNs support wide range of applications.
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4. Two categories of WSN’s
• C1WSN(category 1 WSN)
• C2WSN(category 2 WSN)
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5. Category 1 WSNs (C1WSNs)
• Mesh-based systems
– Multihop radio connectivity among or between
WNs
– Dynamic routing in both the wireless and wireline
portions of the network.
– Ex: Military applications
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6. Category 1 WSNs
• Consist of hundreds (even thousands) of inexpensive WNs
• WNs have operate in an unattended mode
• Battery: piezo electrically or solar-powered
• End devices may be at more than one radio hop away from a routing or forwarding
node
• The forwarding node is a wireless router that supports dynamic routing
• Wireless routers are often connected over wireless links.
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7. Category 1 WSNs
The important characterizations are
 Sensor nodes can support communications on behalf of other (repeaters)
 The forwarding node supports dynamic routing with more than one physical link
to the rest of the network
 The radio links are measured in thousands of meters
 The forwarding node can support data processing or reduction on behalf of the
sensor nodes
Complex and ‘‘meshy’’ wireless systems
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8. Category 1 WSNs
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9. Cooperative and Non cooperative
Nodes
Two types of behavior by intermediate nodes
Cooperative (when a node forwards information on behalf of another node)
Non cooperative (when a node handles only its own communication) .
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10. Category 2 WSNs
• Point-to-point or Multipoint-to-point (star based)
single-hop radio connectivity
• Static routing over the wireless network
• Typically only one route from the WNs to the
companion wire line forwarding node
• Residential control systems typically belong to this
category
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11. Category 2 WSNs
• End devices are one radio hop away from
a terrestrially homed forwarding node.
• Forwarding node (wireless router) is
connected to the terrestrial network via
either landline or a point-to-point
wireless link.
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12. C2WSN
Important characterizations
• Sensor nodes do not support communications on behalf of other
• Forwarding node supports only static routing to the terrestrial network
• Only one physical link to the terrestrial network present from each node
• Radio link is measured in hundreds of meters
• Forwarding node does not support data processing on behalf of the
sensor nodes
Relativelysimplewirelesssystems
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13. C2WSNs
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14. Applications Categories
• Commercial building control
• Environmental (land, air, sea) and agricultural wireless sensors
• Home automation, including alarms (e.g., an alarm sensor that triggers a call to a
security firm)
• National security applications: chemical, biological, radiological, and nuclear
wireless sensors (sensors for toxic chemicals, explosives, and biological agents)
• Industrial monitoring and control
• Metropolitan operations (traffic, automatic tolls, fire, etc.)
• Military sensors
• Process control
• Wireless automated meter reading and load management
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15. RANGE OF APPLICATIONS
• Air traffic control
• Area and theater monitoring (military)
• Automatic control of multiple home systems to improve conservation, convenience, and safety
• Automatic meter reading
• Automating control of multiple systems to improve conservation, flexibility, and security
• Automotive sensors and actuators
• Battlefield management
• Biological monitoring for agents
• Biomedical applications
• Borders monitoring (Mexican and Canadian borders)
• Bridge and highway monitoring (safety)
• Capturing highly detailed electric, water, and gas utility usage data
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16. RANGE OF APPLICATIONS
• Civil engineering applications
• Control of temperature
• Controlling the spread of wild fires
• Defense systems
• Detecting an impulsive event (e.g., a footstep or gunshot) or vehicle (e.g., wheeled or tracked, light
or heavy)
• Earthquake detection
• Electricity load management
• Environmental (land, air, sea) and agricultural wireless sensors
• Environmental control (e.g., tracking soil contamination, habitat monitoring)
• Flexible management of lighting, heating, and cooling systems from anywhere in the home
• Food safety
• Gas, water, and electric meters
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17. RANGE OF APPLICATIONS
• Habitat monitoring
• Habitat sensing
• Health care
• Home automation, including alarms (e.g., an alarm sensor that triggers a call to a
security firm)
• Home monitoring for chronic and elderly patients (collection of periodic or continuous
data and upload to physicians)
• Home security
• Industrial and building monitoring
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18. RANGE OF APPLICATIONS
• Industrial and manufacturing automation
• Inventory control
• Localization
• Military vigilance for unknown troop and vehicle activity
• Mobile robotics
• Monitoring for explosives
• Monitoring for toxic chemicals
• Remotely-controlled home heating and lighting
More and More……………..
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19. Home Control(C2WSN)
Home control applications provide
 control, conservation, convenience, and safety
Sensing applications
• Enable management of lighting, heating, and cooling systems
• Highly detailed electric, water, and gas utility usage data
• Embed intelligence to optimize consumption of natural resources
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20. Home Control
 Enable the installation, upgrading, and networking of a home control system
without wires
 Enable to configure and run multiple systems from a single remote control
 Support the straightforward installation of wireless sensors to monitor a wide
variety of conditions
 Facilitate the reception of automatic notification upon detection of unusual
events.
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21. Home Control
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22. Home Control (Medical Sensor)
• Body-worn medical sensors (e.g., heartbeat sensors)
• Battery-operated devices with network beacons occurring
every few seconds
• Worn by home-resident elderly or people with other medical
conditions
• Sensors have two ongoing processes:
– Heartbeat time logging
– Transmission of heart rate and other information (instantaneous
and average heart rate, body temperature, and battery voltage) 22

23. Building Automation
• Wireless lighting control can easily be accomplished with
ZigBee technology in C2WSNs with
– Dimmable ballasts
A solid-state ballast that can provide variable light output in
response to a signal (from a photo sensor)
Benefits : reduces electricity use , reduces flicker, weight and
noise and generates less heat
– Controllable light switches
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24. Building Automation
Sensing applications enable
• Centralize management of lighting, heating, cooling, and security
• Reduce energy expenses through optimized Heating, ventilation, and air-
conditioning (HVAC).
• Allocate utility costs equitably based on actual consumption
• Extension and upgrading of building infrastructure with minimal effort
• Network and integrate data from multiple access control points
• Deploy wireless monitoring networks to enhance perimeter protection
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25. Building Automation
• Wireless motes installed in individual lighting fixtures in conjunction
with a remote wireless switch capable of controlling the light fixtures
• Integrated sensor communication and i.e., Multiple sensing of
temperature, light, sound, flow, and localization
• Wireless network interface allows the node to be self-contained and to
operate independently
• Support building control applications software
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26. Indoor lighting control
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27. Buildings Energy Scavenging
• Environmental control for buildings energy scavenging
– Airflow measurement technology :
• Use of sensor networks for controlling indoor temperature
• Multi sensor and single-actuator control of temperature
• Sensor network that has at least one sensor in each space
• Information from a WSN to control multiple spaces in a building
• Reduce energy consumption and improve comfort at the same time
• The performance improvement is achieved without changing the
actuation
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28. RFID (Radio Sensor)
• RFID tagging is an ID system that uses small radio frequency identification
devices for identification and tracking purposes.
• An RFID tagging system includes
– Tag
– Read/write device
– Host system application for data collection, processing, and transmission.
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29. RFID (Radio Sensor)
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30. RFID (Radio Sensor)
Applications:
Package tracking, security, banking, control.
Example:
 Airbus’s A380 airplane is equipped with about 10,000 RFID chips
 Plane has passive RFID chips on removable parts ( passenger
seats and plane components)
 Benefits of RFID tagging of airplane parts
 Reducing the time for aircraft-inspection reports
 Optimizing maintenance operations.
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31. WSN applications(C1WSN)
• Military sensor networks to detect and gain information
– Enemy movements
– Explosions
– Phenomena of interest
• Law enforcement and national security tracking or nefarious substance monitoring
• Sensor networks to detect and characterize
– Chemical
– Biological
– Radiological
– Nuclear
– Explosive (CBRNE) attacks and material
• Sensor networks to detect and monitor environmental changes in
– Plains
– Forests
– Oceans 31

32. WSN applications(C1WSN)
Wireless sensor networks
• To monitor vehicle traffic on highways
• To provide security in shopping malls, parking garages
• To spot unoccupied parking place parking lot
• Borders monitoring and satellite uplinks
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33. Sensor and Robots
Intel envisions :
• Mobile robots acting as gateways (sink) into wireless sensor
networks
• Robots embody sensing, actuation, and basic robotics
functions
• Two questions of interest
• Can a mobile robot act as a gateway into a wireless sensor network?
• Can sensor networks take advantage of a robot’s mobility and
intelligence?
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34. Sensor and Robots
To affect this convergence
• Inexpensive standards-based hardware
• Open-source operating systems
• Connectivity modules are required
– Intel XScale microprocessors
– Intel Centrino mobile technology
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35. Sensor and Robots
• Major issue : communication between the robot and the sensor network
• Sensor network equipped with IEEE 802.11 capabilities to bridge the gap between robotics and
wireless networks
• Intel demonstrated with few motes equipped with 802.11 wireless capabilities added to a
sensor network to act as wireless hubs (switch )
• Other motes in the network then utilize each other as links to reach the 802.11-equipped hubs
• The hubs forward the data packets to the main 802.11-capable gateway ( PC or laptop).
• Using some motes as hubs
– Reduces the number of hops that any one data packet has to make to reach the main
gateway,
– Reduces power consumption across the sensor network.
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36. Sensors in a Vineyard(Intel)
• Small sensors in a vineyard in Oregon to monitor microclimates
• Sensors measured temperature, humidity, and other factors to monitor the growing
cycle of the grapes
• Sensors transmitted the data via Multihop to reached a gateway
• Data interpreted at gateway and used to help prevent
– Frostbite (Injury to any part of the body after excessive exposure to extreme cold) ,
– Mold (Microscopic fungi ) and other agricultural problems
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37. Sensors in semiconductor manufacturing fab
At Intel’s semiconductor fabs to predict machines failure ( about to )
 Thousands of sensors track vibrations coming from various pieces of equipment
 Sensor data manually gathered from each node periodically
(schedule determined by the expected failure rate of the equipment)
 Managers determine the particular signature that a well functioning machine should
have
Application of sensor network
 Networking the sensors could make the process more efficient and cost-effective.
 Intel plans to make use of the mote technology to build an application that acquires
data automatically
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38. Intel fab environment with WSNs
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39. Civil and Environmental Engineering Applications
• Sensor technology applicable for
– Buildings, bridges and other structures
• To develop ‘‘smart structures’’
– To self-diagnose potential problems
– Self-prioritize requisite repairs
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40. WSN for Earthquake Zones
• Routine mild tremors
– May not cause visible damage
– Give rise to hidden cracks that could eventually fail during a
higher-magnitude quake
• After a mild earthquake
– Building’s true structural condition may not be extensively visible
without some ‘‘below-the-skin’’ measurement
– Dynamic response sensing sensors
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41. Smart Dust motes
Developed by UC–Berkeley engineers
– Tiny
– Inexpensive
– Battery-powered matchbox-sized WNs
– Operating on TinyOS are designed
– Sense number of factors
• Light & Temperature (for energy-saving applications)
• Dynamic response (for civil engineering analysis)
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42. Motes[UC–Berkeley]
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43. Classification Factors
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44. Classification Factors
Size of the system
 Number of sensors used
 Average (and/or maximum) distance (in hops)
of the sensors to the wired infrastructure
Distribution of the sensor nodes
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45. ANOTHER TAXONOMY OF WSN
TECHNOLOGY
Three types of WSN system (technology) that have been described in are:
1. Nonpropagating WSN systems
2. Deterministic routing WSN systems
a. Aggregating
b. Nonaggregating systems
3. Self-configurable and self-organizing WSN systems
a. Aggregating
b. Nonaggregating systems
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46. Nonpropagating WSN
 No support of dynamic routing to end systems
 Close proximity (one hop) to the wired infrastructure
 Collect and report sensor measurements to nodes connected to
the wired network intern to the end system
 Manually configurable and highly deterministic in deployment
 Environmental sensors deployed in buildings belong to this
category.
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47. Deterministic routing WSN
o The wired and wireless infrastructures play an active
role in routing packets.
o The WNs route - wireless multi hops
o The routes to the wired infrastructure
o Deterministic
o Configured manually
o The number of nodes usually small.
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48. Aggregating systems
 WNs aggregated and forwarded Information received from
‘‘downstream’’
 Intermediary nodes - ability to fuse the information
received from downstream sources
 Weather monitoring systems are examples of aggregating
WSNs
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49. Non aggregating systems
 Information gathered by source node is independent and is transmitted
separately.
 Toll-badge-reading (Tag)systems are examples of non aggregating WSNs
 Nodes are one hop away from the wired node
 No in-network aggregation issue.
 Aggregation functionality is performed in the
 wired infrastructure
 gateway
 No specialized aggregating functionality to be embedded into the WSN
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50. Self-configurable and Self organize systems
 WNs need to self organize themselves (initially or as time goes by) into a
connected network
 Nondeterministic in topological deployment
 Number of nodes can be from hundreds to hundreds of thousands
 Gateway WNs have connectivity to the wired infrastructure for transferring
information to the end systems
 Security network (a target-tracking ) system is an example of a deterministic and
configurable systems ( self-configurable )WSN
 In self-configurable WSNs, the nodes may also aggregate data
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