Wireless Sensor Networks lecture presented in the Fall of 2005. Covering the following: data-dissemination schemes, media access control schemes, distributed algorithms for collaborative processing, and architecture for a wireless sensor network.
INTRODUCTION TO WIRELESS SENSOR NETWORKS.
This powerpoint generally defines Wireless Sensor Networks, the advantages, disadvantages and the general types.
Design Issues and Applications of Wireless Sensor Networkijtsrd
Efficient design and implementation of wireless sensor networks has become a hot area of research in recent years, due to the vast potential of sensor networks to enable applications that connect the physical world to the virtual world. By networking large numbers of tiny sensor nodes, it is possible to obtain data about physical phenomena that was difficult or impossible to obtain in more conventional ways. In future as advances in micro-fabrication technology allow the cost of manufacturing sensor nodes to continue to drop, increasing deployments of wireless sensor networks are expected, with the networks eventually growing to large numbers of nodes.Potential applications for such large-scale wireless sensor networks exist in a variety of fields, including medical monitoring, environmental monitoring, surveillance, home security, military operations, and industrial machine monitoring etc. G. Swarnalatha | R. Srilalitha"Design Issues and Applications of Wireless Sensor Network" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-6 , October 2017, URL: http://www.ijtsrd.com/papers/ijtsrd4688.pdf http://www.ijtsrd.com/engineering/computer-engineering/4688/design-issues-and-applications-of-wireless-sensor-network/g-swarnalatha
in this paper authors made the study of basic clustering algorithm Leach. A comparison is made between Leach and Leach.wireless sensor network advantages, and wireless sensor network dataset
INTRODUCTION TO WIRELESS SENSOR NETWORKS.
This powerpoint generally defines Wireless Sensor Networks, the advantages, disadvantages and the general types.
Design Issues and Applications of Wireless Sensor Networkijtsrd
Efficient design and implementation of wireless sensor networks has become a hot area of research in recent years, due to the vast potential of sensor networks to enable applications that connect the physical world to the virtual world. By networking large numbers of tiny sensor nodes, it is possible to obtain data about physical phenomena that was difficult or impossible to obtain in more conventional ways. In future as advances in micro-fabrication technology allow the cost of manufacturing sensor nodes to continue to drop, increasing deployments of wireless sensor networks are expected, with the networks eventually growing to large numbers of nodes.Potential applications for such large-scale wireless sensor networks exist in a variety of fields, including medical monitoring, environmental monitoring, surveillance, home security, military operations, and industrial machine monitoring etc. G. Swarnalatha | R. Srilalitha"Design Issues and Applications of Wireless Sensor Network" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-6 , October 2017, URL: http://www.ijtsrd.com/papers/ijtsrd4688.pdf http://www.ijtsrd.com/engineering/computer-engineering/4688/design-issues-and-applications-of-wireless-sensor-network/g-swarnalatha
in this paper authors made the study of basic clustering algorithm Leach. A comparison is made between Leach and Leach.wireless sensor network advantages, and wireless sensor network dataset
Wireless Sensor Networks (WSNs) are distributed and independent sensors that are connected and worked together to measure quantities such as temperature, humidity, pressure, noise levels or vibrations. WSNs can measure vehicular movement (velocity, location, etc.) and monitor conditions such as lightning condition, soil makeup and motion. Nowadays, WSNs are utilized in many common applications such as vehicle applications. Some of vehicle applications are: vehicle tracking and detection, tire pressure monitoring, vehicle speed detection, vehicle direction indicator, traffic control, reversing aid sensors etc. Such applications can be divided in major categories such as safety, security, environment and logistics. To implement WSN in an application and have an efficient system, we need to consider about WSN technology, and its components. This paper is aimed at providing reliable software architecture of WSN that could be implemented for better performance and working.
sensors are what we experience the most in our life. they are even working in our body in different aspects. they may be as eyes, ears, skin, tongue etc. when we combine them they make a network. it may be a human sensor network. but i have shared something interesting about wireless sensor networks.
Wireless Sensor Networks (WSNs) are distributed and independent sensors that are connected and worked together to measure quantities such as temperature, humidity, pressure, noise levels or vibrations. WSNs can measure vehicular movement (velocity, location, etc.) and monitor conditions such as lightning condition, soil makeup and motion. Nowadays, WSNs are utilized in many common applications such as vehicle applications. Some of vehicle applications are: vehicle tracking and detection, tire pressure monitoring, vehicle speed detection, vehicle direction indicator, traffic control, reversing aid sensors etc. Such applications can be divided in major categories such as safety, security, environment and logistics. To implement WSN in an application and have an efficient system, we need to consider about WSN technology, and its components. This paper is aimed at providing reliable software architecture of WSN that could be implemented for better performance and working.
sensors are what we experience the most in our life. they are even working in our body in different aspects. they may be as eyes, ears, skin, tongue etc. when we combine them they make a network. it may be a human sensor network. but i have shared something interesting about wireless sensor networks.
Optimization of Transmission Schemes in Energy-Constrained Wireless Sensor Ne...IJEEE
This paper reviews medium access control
(MAC) in wireless sensor network (WSN),and different
management methods to save energy.MAC protocol
controls how sensors access a shared radio channel to
communicate with neighbours.
Energy Efficient Data Aggregation in Wireless Sensor Networks: A Surveyijsrd.com
The use of Wireless Sensor Networks (WSNs) is anticipated to bring lot of changes in data gathering, processing and dissemination for different environments and applications. However, a WSN is a power constrained system, since nodes run on limited power batteries which shorten its lifespan. Prolonging the network lifetime depends on efficient management of sensing node energy resource. Energy consumption is therefore one of the most crucial design issues in WSN. Hierarchical routing protocols are best known in regard to energy efficiency. By using a clustering technique hierarchical routing protocols greatly minimize energy consumed in collecting and disseminating data. To prolong the lifetime of the sensor nodes, designing efficient routing protocols is critical. In this paper, we have discussed various energy efficient data aggregation protocols for sensor networks.
UNIT IV WIRELESS SENSOR NETWORKS (WSNS) AND MAC PROTOCOLS 9 Single node architecture: hardware and software components of a sensor node - WSN Network architecture: typical network architectures-data relaying and aggregation strategies -MAC layer protocols: self-organizing, Hybrid TDMA/FDMA and CSMA based MAC- IEEE 802.15.4.
Designing an Energy Efficient Clustering in Heterogeneous Wireless Sensor Net...IJCNCJournal
Designing an energy-efficient scheme in a Heterogeneous Wireless Sensor Network (HWSN) is a critical issue that degrades the network performance. Recharging and providing security to the sensor devices is very difficult in an unattended environment once the energy is drained off. A Clustering scheme is an important and suitable approach to increase energy efficiency and transmitting secured data which in turn enhances the performance in the network. The proposed algorithm Energy Efficient Clustering (EEC) works for optimum energy utilization in sensor nodes. The algorithm is proposed by combining the rotation-based clustering and energy-saving mechanism for avoiding the node failure and prolonging the network lifetime. This shows MAC layer scheduling is based on optimum energy utilization depending on the residual energy. In the proposed work, a densely populated network is partitioned into clusters and all the cluster heads are formed at a time and selected on rotation based on considering the highest energy of the sensor nodes. Other cluster members are accommodated in a cluster based on Basic Cost Maximum flow (BCMF) to allow the cluster head for transmitting the secured data. Carrier Sense Multiple Access (CSMA), a contention window based protocol is used at the MAC layer for collision detection and to provide channel access prioritization to HWSN of different traffic classes with reduction in End to End delay, energy consumption, and improved throughput and Packet delivery ratio(PDR) and allowing the cluster head for transmission without depleting the energy. Simulation parameters of the proposed system such as Throughput, Energy, and Packet Delivery Ratio are obtained and compared with the existing system.
DESIGNING AN ENERGY EFFICIENT CLUSTERING IN HETEROGENEOUS WIRELESS SENSOR NET...IJCNCJournal
Designing an energy-efficient scheme in a Heterogeneous Wireless Sensor Network (HWSN) is a critical
issue that degrades the network performance. Recharging and providing security to the sensor devices is
very difficult in an unattended environment once the energy is drained off. A Clustering scheme is an
important and suitable approach to increase energy efficiency and transmitting secured data which in turn
enhances the performance in the network. The proposed algorithm Energy Efficient Clustering (EEC)
works for optimum energy utilization in sensor nodes. The algorithm is proposed by combining the
rotation-based clustering and energy-saving mechanism for avoiding the node failure and prolonging the
network lifetime. This shows MAC layer scheduling is based on optimum energy utilization depending on
the residual energy. In the proposed work, a densely populated network is partitioned into clusters and all
the cluster heads are formed at a time and selected on rotation based on considering the highest energy of
the sensor nodes. Other cluster members are accommodated in a cluster based on Basic Cost Maximum
flow (BCMF) to allow the cluster head for transmitting the secured data. Carrier Sense Multiple Access
(CSMA), a contention window based protocol is used at the MAC layer for collision detection and to
provide channel access prioritization to HWSN of different traffic classes with reduction in End to End
delay, energy consumption, and improved throughput and Packet delivery ratio(PDR) and allowing the
cluster head for transmission without depleting the energy. Simulation parameters of the proposed system
such as Throughput, Energy, and Packet Delivery Ratio are obtained and compared with the existing
system.
Engineering Research Publication
Best International Journals, High Impact Journals,
International Journal of Engineering & Technical Research
ISSN : 2321-0869 (O) 2454-4698 (P)
www.erpublication.org
ER Publication,
IJETR, IJMCTR,
Journals,
International Journals,
High Impact Journals,
Monthly Journal,
Good quality Journals,
Research,
Research Papers,
Research Article,
Free Journals, Open access Journals,
erpublication.org,
Engineering Journal,
Science Journals,
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2. Outline
Overview
– Environment Monitoring
– Medical application
Data-dissemination schemes
Media access control schemes
Distributed algorithms for collaborative processing
Architecture for a Wireless Sensor Network
Final Remarks
3. Overview
A Wireless Sensor Network (WSN) consists
of base stations and a number of wireless
sensors (nodes).
5. Overview (Cont.)
Characteristics of Wireless Sensor Networks
Requirements: small size, large number, tether-less, and low cost.
Constrained by
– Energy, computation, and communication
Small size implies small battery
Low cost & energy implies low power CPU, radio with minimum
bandwidth and range
Ad-hoc deployment implies no maintenance or battery replacement
To increase network lifetime, no raw data is transmitted
6. Overview (Cont.)
Ad Hoc Wireless Networks
Large number of self-organizing static or mobile
nodes that are possibly randomly deployed
Near(est)-neighbor communication
Wireless connections
– Links are fragile, possibly asymmetric
– Connectivity depends on power levels and fading
– Interference is high for omnidirectional antennas
Sensor Networks and Sensor-Actuator Networks are
a prominent example.
7. Overview (Cont.)
Distinguishing Features
WSNs are ad hoc networks (wireless nodes that self-organize into
an infrastructureless network).
BUT, in contrast to other ad hoc networks:
Sensing and data processing are essential
WSNs have many more nodes and are more densely deployed
Hardware must be cheap; nodes are more prone to failures
WSNs operate under very strict energy constraints
WSN nodes are typically static
The communication scheme is many-to-one (data collected at a
base station) rather than peer-to-peer
8. Overview (Cont.)
Lifetime
Nodes are battery-powered
Nobody is going to change the batteries. So, each operation
brings the node closer to death.
"Lifetime is crucial!”
To save energy:
Sleep as much as possible.
Acquire data only if indispensable.
Use data fusion and compression.
Transmit and receive only if necessary. Receiving is just as
costly as sending.
9. Overview (Cont.)
Scalability and Reliability
WSNs should
self-configure and be robust to topology changes (e.g., death of
a node)
maintain connectivity: can the Base Station reach all nodes?
ensure coverage: are we able to observe all phenomena of
interest?
Maintenance
Reprogramming is the only practical kind of maintenance.
It is highly desirable to reprogram wirelessly.
10. Overview (Cont.)
Data Collection
Centralized data collection puts extra burden on nodes close to
the base station. Clever routing can alleviate that problem
Clustering: data from groups of nodes are fused before being
transmitted, so that fewer transmissions are needed
Often getting measurements from a particular area is more
important than getting data from each node
Security and authenticity should be guaranteed. However, the
CPUs on the sensing nodes cannot handle fancy encryption
schemes.
11. Overview (Cont.)
Power Supply
AA batteries power the vast majority of existing platforms. They
dominate the node size.
Alkaline batteries offer a high energy density at a cheap price.
The discharge curve is far from flat, though.
Lithium coin cells are more compact and boast a flat discharge
curve.
Rechargeable batteries: Who does the recharging?
Solar cells are an option for some applications.
Fuel cells may be an alternative in the future.
Energy scavenging techniques are a hot research topic
(mechanical, thermodynamical, electromagnetic).
12. Overview (Cont.)
Radio
Commercially-available chips
Available bands: 433 and 916MHz, 2.4GHz ISM bands
Typical transmit power: 0dBm.
Power control
Sensitivity: as low as -110dBm
Narrowband (FSK) or Spread Spectrum communication. DS-SS
(e.g., ZigBee) or FH-SS (e.g., Bluetooth)
Relatively low rates (<100 kbps) save power.
13. Overview (Cont.)
CPU
The Microcontroller Unit (MCU) is the primary choice for
in-node processing.
Power consumption is the key metric in MCU selection.
The MCU should be able to sleep whenever possible,
like the radio.
Memory requirements depend on the application
ATmega128L and MSP430
are popular choices
14. Overview (Cont.)
Sensors
The power efficiency of the sensors is also
crucial, as well as their duty cycle.
MEMS techniques allow miniaturization.
15. Overview (Cont.)
Applications of Wireless Sensor Networks
Military and national security application
Environment monitoring (examples coming)
Medical application (example coming)
Nearly anything you can imagine
16. Environment monitoring (1)
Great Duck Island
• 150 sensing nodes deployed throughout the island relay data
temperature, pressure, and humidity to a central device.
• Data was made available on the Internet through a satellite link.
17. Environment monitoring (2)
Zebranet: a WSN to study the behavior of zebras
• Special GPS-equipped collars were attached to zebras
• Data exchanged with peer-to-peer info swaps
• Coming across a few zebras gives access to the data
18. Medical application
Intel deployed a 130-node network to monitor
the activity of residents in an elder care
facility.
Patient data is acquired with wearable
sensing nodes (the “watch”)
• Vital sign monitoring
• Accident recognition
• Monitoring the elderly
19. Data-dissemination Schemes
Conventional Methods
Direct communication with the base station
– Sensor nodes communicate with the base station directly.
– Energy consuming.
Multi-hop Scheme
– Transmit through some other intermediate nodes.
– Energy consuming.
21. Low Energy Adaptive Clustering
Hierarchy (LEACH)
Designed for sensor networks where an end-user wants to
remotely monitor the environment. Where the data from the
individual nodes must be sent to a central base station, often
located far from the sensor network.
Desirable properties for protocols on these networks:
– Use 100’s – 1000’s of nodes
– Maximize system lifetime
– Maximize network coverage
– Use uniform, battery operated nodes
The use of distributed cluster formation and local processing to
reduce global communication along with randomized rotation of
the cluster-heads allows LEACH to achieve the desired properties
while being energy-efficient.
Data-dissemination Schemes (Cont.)
22. Media Access Control (MAC) Scheme
Two categories of MAC schemes for wireless networks
Contention-based schemes
– Designed for minimum delay and maximum throughput.
– Require transceivers to monitor the channel at all times.
Reservation-based or schedule-based schemes
– Detect the neighboring radios before allocating collision-free
channel to a link.
– TDMA —a natural choice for sensor networks.
23. MAC Scheme (Cont.)
TDMA-based solutions
The self-organizing “super frame” algorithm
– Super frame = TDMA period + BOOTUP period + unused
bandwidth
– Performs well only under the specific conditions.
Power Aware Clustered TDMA (PACT)
– Divide the TDMA structure into control slot and data slot.
– Hard to maintain the cluster when there are mobile nodes.
24. MAC Scheme (Cont.)
Other solutions
Sensor-MAC (SMAC)
– Nodes periodically sleep.
– A node sleeps during transmission period of other
nodes.
– Not suitable for time-critical applications.
25. Architecture for a WSN
Special addressing requirement
Local unique addresses
Data-centric
Example: Each node has an unique number.
Attribute-based naming architecture
Data is named by one or more attributes.
Example: Each node is distinguished by an
attribute – GPS sensors are practical for this.
26. Architecture for a WSN (cont.)
An address-free architecture (AFA)
Advantage
– Randomly select probabilistically unique identifier for each
transaction.
– Spatial locality.
– Temporal locality.
Drawback
– Not applicable when static addressing of nodes is needed.
– Identifier conflict.
27. Final Remarks
Can you think of any applications where a
wireless sensor network would be the best
solution?
Do you foresee wireless sensor networks
becoming ubiquitous within the next ten
years? During your lifetime?
Editor's Notes
ADC - Analog-Digital Converter
industrial, scientific and medical (ISM) : http://en.wikipedia.org/wiki/ISM_band
A microcontroller unit (MCU) is an integrated circuit (IC) that contains many of the functions found in a typical computer system. A microcontroller uses a microprocessor as its central processing unit and incorporates features such as memory, a timing reference, and input/output peripherals, all on the same chip.
Micro-Electro-Mechanical Systems (MEMS) is the integration of mechanical elements, sensors, actuators, and electronics on a common silicon substrate through microfabrication technology.