1. Introduction to
Wireless Sensor Networks
a.Information included in this slides came from multiple sources. We have
tried our best to cite the sources. Please refer to the Table of References
slide (#2) to learn about the sources, when applicable.
b.The slides should be used only for academic purposes (e.g., in teaching a
class), and should not be used for commercial purposes.
1 Introduction to Wireless Sensor Networks
Differences with ad hoc networks
Hardware Setup Overview
3 Introduction to Wireless Sensor Networks
Wireless Sensor Networks are networks
that consists of sensors which are
distributed in an ad hoc manner.
These sensors work with each other to
sense some physical phenomenon and
then the information gathered is
processed to get relevant results.
Wireless sensor networks consists of
protocols and algorithms with self-
4 Introduction to Wireless Sensor Networks
5. Example of WSN
5 Introduction to Wireless Sensor Networks
6. Comparison with ad hoc
Wireless sensor networks mainly use
broadcast communication while ad hoc
networks use point-to-point communication.
Unlike ad hoc networks wireless sensor
networks are limited by sensors limited
power, energy and computational capability.
Sensor nodes may not have global ID
because of the large amount of overhead
and large number of sensors.
6 Introduction to Wireless Sensor Networks
7. Applications of Wireless
The applications can be divided in three
1. Monitoring of objects.
2. Monitoring of an area.
3. Monitoring of both area and objects.
* Classification due to Culler, Estrin,
7 Introduction to Wireless Sensor Networks
8. Monitoring Area
Environmental and Habitat Monitoring
Indoor Climate Control
8 Introduction to Wireless Sensor Networks
9. Example: Precision
• Precision agriculture aims
at making cultural
operations more efficient,
• The information collected
from sensors is used to
evaluate optimum sowing
density, estimate fertilizers
and other inputs needs, and
to more accurately predict
crop yields.9 Introduction to Wireless Sensor Networks
11. Example: Condition-based
Intel fabrication plants
Sensors collect vibration data, monitor
wear and tear; report data in real-time
Reduces need for a team of engineers;
cutting costs by several orders of
11 Introduction to Wireless Sensor Networks
12. Monitoring Interactions between
Objects and Space
Manufacturing Process Flows
12 Introduction to Wireless Sensor Networks
13. Example: Habitat
The ZebraNet Project
Collar-mounted sensors monitor zebra
movement in Kenya
Source: Margaret Martonosi, Princeton University
13 Introduction to Wireless Sensor Networks
14. Characteristics of
Wireless Sensor Networks
Wireless Sensor Networks mainly consists of
sensors. Sensors are -
energy constrained due to their small size.
Wireless networks can also be deployed in
extreme environmental conditions and may
be prone to enemy attacks.
Although deployed in an ad hoc manner they
need to be self organized and self healing and
can face constant reconfiguration.
14 Introduction to Wireless Sensor Networks
15. Design Challenges
The devices deployed maybe of various types
and need to collaborate with each other.
The algorithms need to be centralized as the
processing is carried out on different nodes.
Low Bandwidth Communication
The data should be transferred efficiently
15 Introduction to Wireless Sensor Networks
Large Scale Coordination
The sensors need to coordinate with each other
to produce required results.
Utilization of Sensors
The sensors should be utilized in a ways that
produce the maximum performance and use
Real Time Computation
The computation should be done quickly as
new data is always being generated.
16 Introduction to Wireless Sensor Networks
17. Operational Challenges of
Wireless Sensor Networks
Limited storage and computation
Low bandwidth and high error rates
Errors are common
Node failure are expected
Scalability to a large number of sensor nodes
Survivability in harsh environments
Experiments are time- and space-intensive
17 Introduction to Wireless Sensor Networks
18. Enabling Technologies
Control system w/
Small form factor
Tightly coupled to physical world
Embed numerous distributed
devices to monitor and interact
with physical world
Network devices to coordinate
and perform higher-level tasks
Exploit spatially and temporally dense, in situ, sensing and actuation
18 Introduction to Wireless Sensor Networks
19. Future of WSN
Smart Home / Smart Office
electrical devices in
Better lighting and
heating in office
building has used
19 Introduction to Wireless Sensor Networks
20. Biomedical / Medical
Monitor vital signs
Record anomalies20 Introduction to Wireless Sensor Networks
22. Industrial & Commercial
Numerous industrial and commercial
Agricultural Crop Conditions
In-Process Parts Tracking
Automated Problem Reporting
RFID – Theft Deterrent and Customer Tracing
Plant Equipment Maintenance Monitoring
22 Introduction to Wireless Sensor Networks
23. Traffic Management &
Future cars could use
wireless sensors to:
in the roads to:
–Monitor traffic flows
route updates23 Introduction to Wireless Sensor Networks
24. What are motes?
Motes mainly consist of three parts:-
Mote basically consists of a low cost and
The computer monitors one or more
sensors. Sensors may be for temperature,
light, sound, position, acceleration,
vibration, stress, weight, pressure,
The computer connects to the outside
world with a radio link.
24 Introduction to Wireless Sensor Networks
25. Mica 2 Motes
These motes sold by Crossbow
were originally developed at the
University of California Berkeley.
The MICA2 motes are based on the
ATmega128L AVR microprocessor.
The motes run using TinyOS as
the operating system.
Mica2 mote is one of the most
popular and commercially
available sensors which are
marketed by CrossBow
MICA 2 MOTE
25 Introduction to Wireless Sensor Networks
26. Telosb Motes
Telosb motes have USB programming
An IEEE 802.15.4 compliant, high data rate
radio with integrated antenna, a low-power
There are also equipped with extended
memory and an optional sensor suite
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29. One More Example of Sensor Board
Besides the functions of MTS 300, it mainly adds
29 Introduction to Wireless Sensor Networks