Wireless sensor networks (WSNs) consist of distributed nodes for environmental monitoring, incorporating various sensors and subsystems for processing and communication. Key design factors include fault tolerance, scalability, production costs, hardware constraints, and environmental conditions, which affect node functionality. The document also explores underwater sensor networks, emphasizing the challenges and potential applications in ocean observation and resource monitoring.

2. WIRELESS SENSOR NETWORK
• Sensor network is highly distributed network of
wireless nodes in large number to monitor the
environment.
• Each sensor node have it own limited sensing
region, energy and power.
• Few parameter on basis it works like:– Temperature
– Pressure
– Relatively Humidity.
Contd….

3. WIRELESS SENSOR NETWORK
• Each node of sensor network consist of three sub
system:– The Sensing Sub-System.
– The Processing Sub-System.
– The Communication Sub-System.
• Sensor network consist of different types of sensor
like seismic, thermal, visual and infrared, which
monitored various conditions.

4. WSN DESIGN FACTORS
•
•
•
•
•
•
•
•
Fault Tolerance
Scalability
Production Costs
Hardware Constraints
Sensor Network Topology
Environment
Transmission Media
Power Consumption
Contd…..

5. WSN DESIGN FACTORS
FAULT TOLERANCE
• Each Nodes are prone to unexpected failure
(more than other network)
• Fault tolerance is the ability to sustain sensor
network functionalities without any interruption
due to sensor node failures.

6. WSN DESIGN FACTORS
SCALABILITY
• Size: Number of node (100 ~1000)
• Density : μ(R)=(N R2)/A
• Protocol should
be able to scale to such high degree.
take advantage of the high density of such
networks.

7. WSN DESIGN FACTORS
PRODUCTION COSTS
• The cost of a single node must be low given the
amount of functionalities
• Much less than $1

8. WSN DESIGN FACTORS
HARDWARE CONSTRAINTS
• All these units combined together must
Extremely low power
Extremely small volume

9. WSN DESIGN FACTORS
TOPOLOGY
• Must be maintained specially in very high
densities
Pre-deployment and deployment phase
Post-deployment phase
Re-deployment of additional nodes phase

10. WSN DESIGN FACTORS
ENVIRONMENT
• May be inaccessible
 either because of hostile environment
 or because they are embedded in a structure
• Impact of environment condition
 Temperature
 Humidity
 Movement
 Underwater
 Underground
Contd…..

11. WSN DESIGN FACTORS
ENVIRONMENT
•
•
•
•
•
•
•
Bottom of an ocean
Surface of an ocean during a tornado
Biologically or chemically contaminated field
Battlefield beyond the enemy lines
Home or a large building
Animals
Fast moving vehicles

12. WSN DESIGN FACTORS
TRANSMISSION MEDIA
• RF
• Infrared
• Optical
• Acoustic

13. TYPES OF WSN
• Depending on the environment
1. Terrestrial WSN
• Ad Hoc (unstructured)
• Preplanned (structured)
2. Underground WSN
• Preplanned
• more expensive equipment, deployment, maintenance
3. Underwater WSN
• fewer sensor nodes( sparse deployment)
• more expensive than terrestrial
• acoustic wave communication
– Limited bandwidth
– long propagation delay
– signal fading

14. Why Underwater?
• The Earth is a water planet
– About 2/3 of the Earth covered by oceans
• Largely unexplored, huge amount resources to
discover
• Many potential applications
– Long-term aquatic monitoring
• Oceanography, seismic predictions, pollution
detection, oil/gas field monitoring …
– Short-term aquatic exploration
• Underwater natural resource discovery, antisubmarine mission, loss treasure discovery …

15. UNDER WATER SENSOR NETWORK
• Wireless information transmission through the
ocean is one of the enabling technologies for the
development of future ocean-observation systems
and sensor networks.
• Underwater wireless sensing systems are
envisioned for stand-alone applications and control
of autonomous underwater vehicles (AUVs), and
another is submersibles, also known as remotely
operated vehicles (ROVs).
Contd…..

16. UNDER WATER SENSOR NETWORK
• Among the first underwater acoustic systems was
the submarine communication system developed
in the USA around the end of the Second World
War.

17. 2-TIER ARCHITECTURE

18. HAVE A LOOK !!!
1
2
3
4
5
6
A small chip holding all the
components.
Terminal block for solar panel or
external 12V supply
Molex connector for battery
(paralleled with connector 1)
Debugging interface can be used
to monitor phone communications
using a pc serial port
ICD2 interface for programming
the PIC
Molex connector to mobile phone
Molex connector to underwater
sensor

19. Some Networked Sensor Node
LWIM III
AWAIRS I
UCLA, 1996
UCLA/RSC 1998
Geophone, RFM
Geophone, DS/SS
radio, PIC, star
Radio, strongARM,
network
Multi-hop networks
UCB Mote, 2000
4 Mhz, 4K Ram
512K EEProm,
128K code,
CSMA
half-duplex RFM radio
WINS NG 2.0
Sensoria, 2001
Node development
platform; multisensor, dual radio,
Linux on SH4,
Preprocessor, GPS
Processor
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20. WORKING OF UWSN

21. SOLUTION FOR ENERGY LOSS
• What is the Solution....?
Hardware
Solution
Software
Solution
Energy Efficient Algorithm or
Protocol

22. Comparison of Energy Sources
Power (Energy) Density
Batteries (Zinc-Air)
Batteries(Lithium ion)
Source of Estimates
3
1050 -1560 mWh/cm (1.4 V)
Published data from manufacturers
3
300 mWh/cm (3 - 4 V)
Published data from manufacturers
2
15 mW/cm - direct sun
Solar (Outdoors)
2
0.15mW/cm - cloudy day.
Published data and testing.
.006 mW/cm2 - my desk
Solar (Indoor)
Vibrations
2
0.57 mW/cm - 12 in. under a 60W bulb
3
0.001 - 0.1 mW/cm
Testing
Simulations and Testing
2
3E-6 mW/cm at 75 Db sound level
Acoustic Noise
Passive Human
Powered
9.6E-4 mW/cm2 at 100 Db sound level
1.8 mW (Shoe inserts >> 1 cm )
Published Study.
Thermal Conversion
0.0018 mW - 10 deg. C gradient
Published Study.
2
Direct Calculations from Acoustic Theory
3
80 mW/cm
3
Nuclear Reaction
1E6 mWh/cm
3
300 - 500 mW/cm
Fuel Cells
~4000 mWh/cm
3
Published Data.
Published Data.
With aggressive energy management, ENS might
live off the environment.
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23. FUTURE SCOPE
• Reduce
– Maintenance
– Hardware Size
– Costing
• Increase
– System Life
– Gather more Information
– Future Predictions