This document provides an overview of wireless sensor networks. It discusses wireless communication technologies, the need for wireless communication, and defines wireless sensor networks. It describes the characteristics, architecture, operating systems, applications, and technical challenges of wireless sensor networks. Finally, it discusses some companies that manufacture wireless sensor network products, including Cisco, IBM, and Libelium.

1. WIRELESS SENSOR
Y O G E S H F U L A R A
1 3 2 0 7 0 2 3
P E C U N I V E R S I T Y O F T E C H N O L O G Y
C H A N D I G A R H
NETWORKS

2. INDEX
• Wireless Communication
• Need Of wireless Communication
• Wireless Sensor Network
• Why wireless sensor required now?
• Characteristics
• Architecture
• Operating System for WSNs
• Wireless Sensor Networks Application
• Simulation Software
• Some Technical Challenges
• Manufacturing Company and their products
• Summary and Conclusions

3. WIRELESS COMMUNICATION

4. WIRELESS COMMUNICATION
Wireless communication is the transfer of information between two or
more points that are not connected by an electrical conductor.
Wireless communication is among technology’s biggest contributions
to mankind. Wireless communication involves the transmission of
information over a distance without help of wires, cables or any other forms
of electrical conductors. The transmitted distance can be anywhere between a
few meters (for example, a television’s remote control) and thousands of
kilometres (for example, radio communication).
Types of wireless communication
• AM/FM
• Infrared (IR) wireless communication
• Wi-Fi
• WiMAX
• OpticalWireless Communication

5. BLOCK DIAGRAM OF WIRELESS
COMMUNICATION

6. NEED OF WIRELESS COMMUNICATION
• Flexibility : the benefits of wireless networks over wired
networks and one of the benefits of this flexibility, as radio
waves go through walls and wireless computer you can be in
any domain Point.
• Increased mobility and collaboration
• Roam without losing your connection
• Work together more effectively
• Improved responsiveness
• Connect to the information you need when you need it
• Provide better customer service

7. NEED OF WIRELESS COMMUNICATION
• Better access to information
• Connect hard-to-reach areas
• Improve your processes
• Easier network expansion
• Add users quickly
• Grow your network cost-effectively
• Enhanced guest access
• Give secure network access to customers and business
partners
• Offer a value-added service

8. WIRELESS NETWORK
A wireless network is any type of computer network that uses
wireless data connections for connecting network nodes
• Types of Wireless Network
• Wireless PAN (Personal Area Network)
• Wireless LAN (Local Area Network)
• Wireless mesh network
• Wireless MAN (Metropolitan Area Networks)
• Wireless WAN (Wide Area Network)
• Cellular network
• Wireless Sensor Network

9. WHAT IS A WIRELESS SENSOR
NETWORK?
• Wireless Sensor Node = Sensor +
Actuator + ADC +
Microprocessor + Powering Unit
+ Communication Unit (RF
Transceiver)
• An ad hoc network of self-powered
and self-configuring
sensor nodes for collectively
sensing environmental data and
performing data aggregation and
actuation functions reliably,
efficiently, and accurately.
GPS Sensor Node

10. WIRELESS SENSOR NETWORK
Definition
“A wireless sensor network (WSN) is a wireless network
consisting of spatially distributed autonomous devices using
sensors to cooperatively monitor physical or environmental
conditions, such as temperature, sound, vibration, pressure,
motion or pollutants, at different locations.”

11. WIRELESS SENSOR NETWORKS
• Formed by hundreds or thousands of nodes that communicate
with each other and pass data along from one to another
• Research done in this area focus mostly on energy aware
computing and distributed computing
Super Node
Links to Other networks or
Similar Super Nodes
Motes

12. WIRELESS SENSOR NETWORKS
• Sensor networks are the key to gathering the information
needed by smart environments, whether in buildings,
utilities, industrial, home, shipboard, transportation systems
automation, or elsewhere. Recent terrorist and guerilla
warfare countermeasures require distributed networks of
sensors that can be deployed using, e.g. aircraft, and have
self-organizing capabilities. In such applications, running
wires or cabling is usually impractical. A sensor network is
required that is fast and easy to install and maintain.

13. WHY WIRELESS SENSORS NOW?
• Moore’s Law is making sufficient CPU performance available
with low power requirements in a small size.
• Research in Materials Science has resulted in novel sensing
materials for many Chemical, Biological, and Physical sensing
tasks.
• Transceivers for wireless devices are becoming smaller, less
expensive, and less power hungry.
• Power source improvements in batteries, as well as passive
power sources such as solar or vibration energy, are expanding
application options.

14. CHARACTERISTICS OF WSN’S
The main characteristics of a WSNs Include
• Easy to use
• Power Consumption Constraints for nodes using batteries
• Mobility of nodes
• Scalability to large scale of development
• Ability to withstand harsh environmental conditions
• Cross Layer design
• Ability to cope with node Failures

15. GENERAL WSN SYSTEM
ARCHITECTURE

16. GENERAL WSN SYSTEM ARCHITECTURE
– Constructing a platform for WSN falls into the area of embedded system
development which usually consists of developing environment, hardware and
software platforms.
1. Hardware Platform
Consists of the following four components:
a) Processing Unit
Associates with small storage unit (tens of kilo bytes order) and
manages the procedures to collaborate with other nodes to carry out the
assigned sensing task
b) Transceiver Unit
Connects the node to the network via various possible transmission
medias such as infra, light, radio and so on

17. GENERAL WSN SYSTEM ARCHITECTURE
1. Hardware Platform
c) Power Unit
Supplies power to the system by small size batteries which makes the
energy a scarce resource
d) Sensing Units
Usually composed of two subunits: sensors and analog-to-digital
Converters (ADCs). The analog signal produced by the sensors are
converted to digital signals by the ADC, and fed into the processing unit

18. GENERAL WSN SYSTEM ARCHITECTURE
2. Software Platform
Consists of the following four components:
a) Embedded Operating System (EOS)
Manages the hardware capability efficiently as well as supports
concurrency-intense operations. Apart from traditional OS tasks such as
processor, memory and I/O management, it must be real-time to rapidly
respond the hardware triggered events, multi-threading to handle
concurrent flows
b) Application Programming Interface (API)
A series of functions provided by OS and other system-level components
for assisting developers to build applications upon itself

19. OPERATING SYSTEM FOR WSN
• Tiny Os
• Lite Os
• Contiki
• Riot With C & C++
• EPIKA Enterprise

20. WORKING TOOL/ SIMULATOR
• OPNET
• OMNET++
• NETSIM
• WSNET
• NS2
• MATLAB

21. APPLICATIONS OF WIRELESS
SENSORS NETWORK

22. PERVASIVE COMPUTING (SMART HOME /
OFFICE)
• Sensors controlling
appliances and
electrical devices in the
house.
• Better lighting and
heating in office
buildings.
• The Pentagon building
has used sensors
extensively.

23. BIOMEDICAL / MEDICAL
• Health Monitors
• Glucose
• Heart rate
• Cancer detection
• Chronic Diseases
• Artificial retina
• Cochlear implants
• Hospital Sensors
• Monitor vital signs
• Record anomalies

24. MILITARY
Remote deployment of sensors
for tactical monitoring of enemy
troop movements.

25. INDUSTRIAL & COMMERCIAL
• Numerous industrial and commercial applications:
• Agricultural Crop Conditions
• Inventory Tracking
• In-Process Parts Tracking
• Automated Problem Reporting
• RFID – Theft Deterrent and Customer Tracing
• Plant Equipment Maintenance Monitoring

26. TRAFFIC MANAGEMENT & MONITORING
 Future cars could use
wireless sensors to:
– Handle Accidents
– Handle Thefts
Sensors embedded in
the roads to:
–Monitor traffic flows
–Provide real-time route
updates

27. SOME TECHNICAL CHALLENGES

28. NOISY SENSORS
Sensor readings can be inaccurate. Protocols need to recognize
this.
GPS Sensor
Accurate within
2.8 meters
Relative Humidity Sensor
Accuracy of ±5%
±8% at 90% Relative Humidity
±2% with calibration

29. WIRELESS CHANNEL CONDITIONS
• Limitations of wireless channels
• Noisy
• Interference
• Link Contention
• Unidirectional Links
• But inherently a broadcast medium

30. ENVIRONMENTAL FACTORS
• Wireless sensors need to operate in conditions
that are not encountered by typical computing
devices:
• Rain, sleet, snow, hail, etc.
• Wide temperature variations
• May require separating sensor from electronics
• High humidity
• Saline or other corrosive substances
• High wind speeds

31. NETWORKING ISSUES IN
WIRELESS SENSOR NETWORKS

32. SPECIFIC DESTINATIONS
• Messages mostly
routed to base stations
• Not arbitrary source-destination
pairs
• Opportunities for
optimization
• Network traffic is not
balanced
Sensing Zone with sensor-coordinator,
sensing-collaborators, and backbone nodes

33. HOP-BY-HOP COMMUNICATION
• Energy for wireless
communication grows with
distance d at the rate d2 –
d4.
• Multiple short hops are
cheaper than one long hop.
• Scheduling many nodes
leads to high contention –
not scalable.

34. TIME SYNCHRONIZATION
• Data aggregation assumes time synchronization!!!
• Need to know events at different sensors
are temporally related.
• Allows one to distinguish multiple targets.
• Not trivial to accomplish in the
constrained environment of sensor
networks.

35. SCALABILITY!
• Size of sensor networks will grow because:
• Sensors more affordable as cost decreases
• Redundant sensors provide
• Reliability
• Fault tolerance
• Longer network lifetime
• Protocols will support large networks
• Applications will exist for larger networks

36. SERVICE DISCOVERY PROTOCOL
Anyone need
a printer?

37. SERVICE DISCOVERY PROTOCOL
• For a wireless sensor network, service discovery provides:
• Automated calibration of new devices
• Highly dynamic system configurations
• Cooperation among resource poor devices
• Solves resource sharing device
• Storage and long-range networking services can be obtained
from a nearby server
• Reduces duplication of functionality
• Supports novel interactions in the future

38. SECURITY ISSUES
• Concerns about misuse and privacy
• Privacy issues may slow consumer adoption of technology
• User tracking – RFID concerns
• Has not proved true on the Internet!
• Authentication and privacy are not always complementary
objectives
• Do not want your medical sensor hacked!!
• Data tampering and computer viruses could be a nightmare!

39. LIABILITY AND SAFETY CONCERNS
Companies may adopt wireless sensors to
reduce liability, but wireless sensors could
also increase liability:
– Use in critical applications could be limited
• Imagine a medical sensor fails!!
• Or an automotive theft deterrent system failure
– Companies will be slow to adopt technology
that increases their legal exposure
• May delay adoption

40. MANUFACTURING COMPANY AND
THEIR PRODUCTS
• Cisco
• Router/Switches(series 2900 to 5600)
• Wi-Fi
• Cisco Aironet 1552S Outdoor Access Point Data Sheet
• Monitoring a chemical treatment plant while providing
onsite security via wireless video surveillance
• Monitoring the equipment and gauges on an oil rig while
an onsite worker downloads schematics, blueprints, or
work instructions to a handheld Wi-Fi tablet
• Providing real-time information to an onsite engineer
about changes to processes and equipment so that
abnormalities can be dealt with immediately

41. IBM
• Smart Water Sensors to monitor water quality in rivers,
lakes and the sea | Libelium
• Libelium launched a Smart Water wireless sensor platform to simplify
remote water quality monitoring. Equipped with multiple sensors that
measure a dozen of the most relevant water quality parameters, Wasp
mote Smart Water is the first water quality-sensing platform to feature
autonomous nodes that connect to the Cloud for real-time water control.
• The water quality parameters measured include pH, dissolved oxygen
(DO), oxidation-reduction potential (ORP), conductivity (salinity),
temperature and dissolved ions (Na+, Ca+, F-, Cl, Br-, I-, Cu2+, K+,
Mg2+, NO3-).

42. IBM
Open Garden – Hydroponics & Garden Plants Monitoring
for Arduino
• The platform allows to control the state of the plants by sensing
several parameters:
• Soil moisture (Indoor & Outdoor kits)
• Temperature + Humidity + Light (All kits)
• Water sensors: pH, Conductivity, Temperature (Hydroponics kit
• Then it uses different types of actuators to modify the state of the
plants by irrigating them or activating lights and oxygen pumps:
• Water pump + Droppers for Drip Irrigation (Indoor kit)
• Electro valve + Sprinkler for Sprinkling (Outdoor kit)
• Oxygen Pump + Growing Light (Hydroponics kit)

43. IBM
• 400MHz RF transceiver geared for wireless smart
energy apps
• The transceiver is integrated with a highly configurable base band that
enables users to customise transceiver performance for specific
applications ranging from wireless smart energy management and
security control in homes and buildings to long-range remote industrial
monitoring.
• To achieve low power consumption in RF transceiver, performance is
typically sacrificed, resulting in degradations of sensitivity, channel
selectivity and interference immunity during the wireless signal
communication process.

44. LIBELIUM COMUNICACIONES DISTRIBUIDAS S.LTD
• Libelium today announced the availability of a new Smart Lighting
solution for Smart Cities deployments based on the modular Wasp mote
Plug & Sense! wireless sensor network platform. Measuring ambient light
(luminosity) with a new set of direction able sensor probes, Libelium’s
Smart Lighting device also includes temperature and humidity sensors and
is capable of monitoring conditions inside buildings or in tunnels, and
outside, in the streets.

45. • Wireless Sensor Networks to monitor food sustainability
• Food security" refers to the ability of food systems to ensure that everyone has
enough food to live a healthy life. To prevent food insecurity, we require reliable
food systems at each stage of the food cycle: from food production and
harvesting, during transport and distribution, at the shops we buy at and in the
social settings wherever we consume food, and in the management of the
resulting bio-waste outputs. Libelium's Wasp mote sensors can be used to
monitor and control the whole food cycle.

46. • Some other products of Libelium
• Nature Preservation by Monitoring and Studying the Habitat of Bats
with Wasp mote
• New e-Learning Platform for ZigBee sensor networks
• Wireless Sensor Networks enhancing the efficiency and safety of
logistics operations
• Smart City project in Salamanca to monitor Air Quality and Urban
Traffic with Wasp mote
• E.t.c

47. COMPANY
• As the world is growing day by day technology is enhancing
per day for better environment, safe world and easy world.
There are lot of company manufacturing in the field of
wireless sensor
• INTEL
• Microsoft
• Global Markets and Technologies for Wireless Sensors
• and more

48. SUMMARY AND CONCLUSIONS
• Wireless sensor networks have a bright future
• Many applications have been proposed
• Potential to revolutionize human-computer interactions
• Availability of sensors will lead to new and exciting
applications
• A lot of research remains to be done
• Many obstacles to overcome
• Wireless sensors will not evolve into traditional
computers
• Allow realism to guide research efforts