The ppt describes the WSN clustering with the detailed description of the sensor node used in the network.

1. SENSOR NODE ARCHITECTURE
AND WSN CLUSTERING
Presented By:
Shubhi Singh
P14EC021

2. REVIEW
• Getting Known to WSN Environment
• Applications of WSN
• Differences with ad hoc networks
• Characteristics
• Challenges
• Sources of energy Inefficiency
• WSN Routing Protocols
• Future
• Hardware Setup Overview

3. OUTLINE
 What is sensor node?
 Sensor node architecture
 Description of Main components of a wireless
sensor node
 Processor, radio, sensors, batteries
 Energy supply
 WSN Clustering
 Clustering Objective
 Brief Of Leach Protocol

4. SENSOR NODE
A sensor node, also
known as
a mote (chiefly in
North America), is a
node in a
wireless sensor network
that is capable of
performing some
processing, gathering
sensory information
and communicating
with other connected
nodes in the network.
MICA2 NodeMICA2 Node

5. MAIN COMPONENTS
NODE ARCHITECTURENODE ARCHITECTURE

6. ADC converts the output of a sensor - which is aADC converts the output of a sensor - which is a
continuous, analog signal - into a digital signal. It requirescontinuous, analog signal - into a digital signal. It requires
two steps:two steps:
1.1. the analog signal has to be quantizedthe analog signal has to be quantized
 allowable discrete values is influenced :allowable discrete values is influenced :
(a) by the frequency and magnitude of the signal(a) by the frequency and magnitude of the signal
(b) by the available processing and storage resources(b) by the available processing and storage resources
2.2. the sampling frequencythe sampling frequency
 Nyquist rate does not suffice because of noise and transmission errorNyquist rate does not suffice because of noise and transmission error
 resolution of ADC - an expression of the number of bits that can be used toresolution of ADC - an expression of the number of bits that can be used to
encode the digital outputencode the digital output
where Q is the resolution in volts per step (volts per outputwhere Q is the resolution in volts per step (volts per output
code);code); EppEpp is the peak-to-peak analog voltage;is the peak-to-peak analog voltage; MM is the ADC’sis the ADC’s
resolution in bitsresolution in bits
Sensor SubsystemSensor Subsystem

7. PROCESSOR SUBSYSTEM
 The processor subsystem
 interconnects all the other subsystems and some
additional peripheries
 its main purpose is to execute instructions pertaining
to sensing, communication, and self-organization
 It consists of
 processor chip
 nonvolatile memory - stores program instructions
 active memory - temporarily stores the sensed data
 internal clock

8.  Major Options For Processors:
Microcontroller – general purpose processor,
optimized for embedded applications, low power
consumption
DSP – optimized for signal processing tasks, not
suitable here(some tasks require protocols (and not
numerical operations) that require periodical
upgrades or modifications (i.e. the networks should
support flexibility in network programming)
FPGA – may be good for testing(complex and
costly)
ASIC – only when peak performance is needed, no
flexibility (high development costs and lack of re-
configurability)

9. COMPARISON
Working with a micro-controller is preferred if the design goal isWorking with a micro-controller is preferred if the design goal is
to achieve flexibilityto achieve flexibility
Working with the other mentioned options is preferred if powerWorking with the other mentioned options is preferred if power
consumption and computational efficiency is desiredconsumption and computational efficiency is desired
DSPs are expensive, large in size and less flexible; they are bestDSPs are expensive, large in size and less flexible; they are best
for signal processing, with specific algorithmsfor signal processing, with specific algorithms
FPGAs are faster than both microcontrollers and digital signalFPGAs are faster than both microcontrollers and digital signal
processors and support parallel computing; but their productionprocessors and support parallel computing; but their production
cost and the programming difficulty make them less suitablecost and the programming difficulty make them less suitable
ASICs have higher bandwidths; they are the smallest in size,ASICs have higher bandwidths; they are the smallest in size,
perform much better, and consume less power than any of theperform much better, and consume less power than any of the
other processing types; but have a high cost of production owingother processing types; but have a high cost of production owing
to the complex design processto the complex design process

10. COMMUNICATION INTERFACES
 The choice is often between serial interfaces :
 Serial Peripheral Interface (SPI)
 General Purpose Input/Output (GPIO)
 Secure Data Input/Output (SDIO)
 Inter-Integrated Circuit (I2
C)
 Among these, the most commonly used buses are SPI and
I2
C

12. TRANSCEIVER CHARACTERISTICS
 Service to upper layer: packet,
byte, bit
 Power consumption
 Supported frequency, multiple
channels
 Data rate
 Modulation
 Power control
 Communication range
 etc.

13. TRANSCEIVER STATES
 Transceivers can be put into different
operational states, typically:
 TransmitTransmit
 ReceiveReceive
 IdleIdle – ready to receive,
but not doing so
 SleepSleep – significant parts
of the transceiver are
switched off
RxRxTxTx IdleIdle
SleepSleep

14. SENSORS
 Main categories
 Passive, omnidirectionalPassive, omnidirectional
 Examples: light, thermometer, microphones,
hygrometer, …
 Passive, narrow-beamPassive, narrow-beam
 Example: Camera
 Active sensorsActive sensors
 Example: Radar
 Important parameter: Area of coverage
 Which region is adequately covered by a given
sensor?

15. ENERGY SUPPLY
 Goal: provide as much energy as possible at
smallest cost/volume/weight/recharge
time/longevity
 In WSN, recharging may or may not be an option
 Options
 Primary batteriesPrimary batteries – not rechargeable
 Secondary batteriesSecondary batteries – rechargeable, only makes
sense in combination with some form of energy
harvesting

16. ENERGY SUPPLY - REQUIREMENTS
 Low self-discharge
 Long shelf life
 Capacity under load
 Efficient recharging at low current
 Good relaxation properties (seeming self-
recharging)
 Voltage stability (to avoid DC-DC conversion)

17. PORTABLE SOLAR CHARGERS
 Foldable Solar Chargers
 http://www.energyenv.co.uk/
FoldableChargers.asp
 Solargorilla
 http://powertraveller.com/iwantsome/primatepowe

18. SUMMARY
 The need to build cheap, low-
energy, (small) devices has various
consequences
 Much simpler radio frontends and
controllers
 Energy supply and scavenging are a
premium resource
 Power management is crucial

19. WHAT IS CLUSTERING
• Nodes divided in virtual group according to some rulesNodes divided in virtual group according to some rules
• Nodes belonging in a group can execute different functionsNodes belonging in a group can execute different functions
from other nodes.from other nodes.
Cluster memberCluster member
ClusterheadClusterhead
Gateway nodeGateway node
Intra-Cluster linkIntra-Cluster link
Cross-clusterCross-cluster
linklink

20. Clustering ObjectivesClustering Objectives::
•Allows aggregationAllows aggregation
•Limits data transmissionLimits data transmission
•Facilitate the reusability of the resourcesFacilitate the reusability of the resources
•CHs and gateway nodes can form a virtualCHs and gateway nodes can form a virtual
backbone for intercluster routingbackbone for intercluster routing
•Cluster structure gives the impression of aCluster structure gives the impression of a
smaller and more stable networksmaller and more stable network
•Improve network lifetimeImprove network lifetime
• Reduce network traffic and the contentionReduce network traffic and the contention
for the channelfor the channel
• Data aggregation and updates take placeData aggregation and updates take place
in CHsin CHs

21. LITERATURE SURVEY OF CLUSTERING
ALGORITHMS
• HEED: A hybrid energy efficient distributed clusteringHEED: A hybrid energy efficient distributed clustering
approach for ad-hoc sensor networksapproach for ad-hoc sensor networks
• MRECA: Mobility resistant efficient clustering approachMRECA: Mobility resistant efficient clustering approach
for ad-hoc sensor networksfor ad-hoc sensor networks
• Energy efficient dynamic clustering algorithm for ad-hocEnergy efficient dynamic clustering algorithm for ad-hoc
sensor networkssensor networks
• LEACH-Energy efficient communication protocol for WSNLEACH-Energy efficient communication protocol for WSN
• EEDC-Dynamic clustering and energy efficient routingEEDC-Dynamic clustering and energy efficient routing
technique for WSNtechnique for WSN

22. LEACH PROTOCOL
LEACH ProtocolLEACH Protocol

23. Intracluster – InterclusterIntracluster – Intercluster
communicationcommunication
HEED ProtocolHEED Protocol

24. REFERENCES
 A hybrid energy efficient distributed clustering approach for ad-hoc sensor networks
 Node Clustering in Wireless Sensor Networks by Considering Structural Characteristics of
the Network Graph, Nikos Dimokas,Dimitrios Katsaros,Yannis Manolopoulos, 4th
ITNG
Conference, Las Vegas, NV, 2-4/April/2007
 On Energy Efficiency in Collaborative Target Tracking in Wireless Sensor Network: A
Review, Demigha, O. ; Ecole Militaire Polytech., Algiers, Algeria ; Hidouci, W.-K. ; Ahmed,
T., IEEE Communications Society, 31 July 2013
 Analysis and design of energy-oriented security protocols for Wireless Sensor
Networks, Guo Xiaowang ; Zhu Jianyong (Electronic and Mechanical Engineering
and Information Technology (EMEIT), 2011 International Conference on ),Volume:
5 , 2011
 Fundamental of Wireless Sensor Network:theory and practical by Waltenegus
Dargie and Christian paullabauer @2010.