1/24 experimental analysis of area localization scheme for sensor networks vijay chandrasekhar 1,...
TRANSCRIPT
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Experimental Analysis of Area Localization Scheme for Sensor Networks
Vijay Chandrasekhar1, Zhi Ang Eu1, Winston K.G. Seah1,2 and Arumugam Pillai Venkatesh2
1Network Technology DepartmentInstitute For Infocomm Research, A*STAR, Singapore
2National University of Singapore
WCNC2007
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Outline
Introduction Related Work Enhancement To Area Localization Scheme Experimental Setup and Results Conclusions
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Introduction
The location information is important for a large wireless sensor network.
To identify the exact location of every sensor may not be feasible or necessary.
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Introduction
Localization algorithm Range based
Add additional hardware (e.g: GPS) Range-free based
Location information can be obtained RSSI Time of arrival or time difference of arrival Angle of arrival measurements
Probabilistic techniques
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Related Work- ALS Algorithm
Q. Yao, S.K. Tan, Y. Ge, B.S. Yeo, Q. Yin, “An Area Localization Scheme for Large Wireless Sensor Networks”,Proceedings of the IEEE 61st Semiannual Vehicular Technology Conference (VTC2005-Spring), May 30 - Jun 1, 2005, Stockholm, Sweden.
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Related Work- ALS Algorithm
There are three types of nodes in ALS Reference nodes Sensor nodes Sinks
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Related Work- ALS Algorithm
Reference nodes Send out beacon signal to help the sensor nodes
construct their signal coordinates. Equipped with GPS or placed in pre-
determined locations.
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Related Work- ALS Algorithm
Sensor nodes Monitor environment. Use a simple signal coordinate to indicate their
information to the sinks. Only knows its own signal coordinate and attac
h this to the data. Example:
<R1,R2,R3,R4>
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Related Work- ALS Algorithm
Sinks Charge of collecting information from sensor
node and then processing the information. Knows the location of all the reference node
and there respective transmitted power level.
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Related Work- ALS Algorithm
A
B C
D
Reference node
Power Level 1
Power Level 2
<1,0,0,0>
<2,0,0,0>
<0,1,0,0>
<2,2,0,0>
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Related Work- ALS Algorithm
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Related Work- ALS Algorithm
Ideal propagation model
ALS only functions in an ideal radio channel.
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Enhancement To ALS
Shadowing Propagation model
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Enhancement To ALS
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Enhancement To ALS
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Enhancement To ALS
Shadow and fading effects ALS did not consider shadowing and fading.
Use overlapping ranges to construct the signal map.
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Experimental Setup and Results Nodes :MicaZ motes Area size:
Indoor 10m x 10m Multi-purpose hall (MPH)
Outdoor 30m x 30m Open field Park
35 Sensors indoor 30 Sensors outdoor 8 reference nodes
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Experimental Setup and Results
The circular ring between radii √(A/π) and 2√(A/π) is defined as the 1-hop neighboring region of the node.
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Experimental Setup and Results
Summary of experimental results
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Experimental Setup and Results
Actual versus Estimated Locations of Sensors (MPH)
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Experimental Setup and Results
Actual versus Estimated Locations of Sensors (Open Field)
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Experimental Setup and Results
Actual versus Estimated Locations of Sensors (Park with obstacles)
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Experimental Setup and Results
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Conclusions
In this paper, they Modified and implemented the ALS algorithm
on a experimental study. ALS is comparable or better than other
implemented localization scheme, and ALS has lower complexity.
Future works They will incorporate routing protocols on ALS
algorithm.
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