Post on 12-Jan-2016
description
PS
Adaptive Computing and Networking Laboratory
WASN 2009
A Counter-Based RFID Anti-Collision Protocol
Using Parallel Splitting
Ming-Kuei Yeh and Jehn-Ruey JiangDepartment of Computer Science and Information Engineering
National Central University
PS
Adaptive Computing and Networking Laboratory
WASN 2009
Outline
• Introduction• Anti-collision protocols• Proposed protocol • Evaluation• Conclusion
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Outline
• Introduction• Anti-collision protocols• Proposed protocol • Evaluation• Conclusion
• Introduction
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Introduction RFID system
• RFID (Radio Frequency IDentification) system
Reader
Tag (Transponder)
Application
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Introduction Application
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Tag 1
reader
Tag 2
Tag 3
Interrogation zone
Introduction Interrogation zone
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Interrogation zone
tag
Tag collision problem: collision occurs when multiple tags respond to the same reader simultaneously
reader
Introduction Tag-to-tag interference
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Outline
• Introduction• Anti-collision protocols• Proposed protocol • Evaluation• Conclusion
• Anti-collision protocols
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Anti-collision protocols category
• Anti-collision protocolsFor solving the tag collision problem
Two classes• ALOHA based • Tree based
– deterministic tree-based
– probabilistic counter-based
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
S1 S2 S3 S4 S5 S6 S7 S8 S9 S10 S11 S12 S13 S14 S15
Tag1
Tag2
Tag3
Tag4
Tag5
Tag6
Tag7
Tag8
Tag9
Tag10
Collision !
Collision !
S: time slotAn example of slotted ALOHA protocol
Anti-collision protocols ALOHA based
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
0 1
0
0
0
1
1
11
1
0
0
Tag1 Tag2 Tag3 Tag4 Tag5 Tag6
An example of bit-by-bit tree protocol
Anti-collision protocols Tree based
ID:0010
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PS
Adaptive Computing and Networking Laboratory
WASN 2009C = 0C= counter
Anti-collision protocols Counter based
C = 0 C =1C = 0 C =2
C = 0 C =1
C = 0
C = 0 C =4
C =3
C =2
C = 0 C =1
Tag1
C = 0
C = 0
C = 0
C = 0
C =3
C =2
C =1
C = 0 C =0
Tag1
C = 0
C = 0
C = 0
C = 0
An example of a counter-based protocol: ISO/IEC18000-6B
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Outline
• Introduction• Anti-collision protocols• Proposed protocol • Simulation• Conclusion
• Proposed protocol
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Proposed protocol
• Parallel Splitting (PS) forRFID Tag Anti-Collision
Counter based anti-collision protocol
Using two schemes• Parallel Splitting
• Adaptive Identification-Tree Height Adjustment
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
C= counter
C = 0
Proposed protocol Parallel Splitting
C = 0 C =1
C = 0
C =1
C = 0 C =1
C = 0
C = 0
C = 2 C =3
C =0
C =0
C =0
C =0
C =1
C =1 C =2 C =3
C =1 C =2 C =3 C =4 C =5 C =6 C =7
C =0 C =1 C =2 C =3 C =4 C =5 C =6 C =7 C =8 C =9 C =10 C =11 C =12 C =13 C =14
Tag1
Just left-shift their counters one bit and add one or zero randomly to the counters.
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PS
Adaptive Computing and Networking Laboratory
WASN 2009• Why do we need to adjust the
identification-tree height?May not be so lucky to split the tags perfectly(to be a full tree)
Proposed protocol Adaptive Identification-Tree Height Adjustment
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
• Analyzing the ratio of the numbers of
leaf nodes that including zero tag, one tag
and multiple tags
p(S): the probability that there are S tags residing at a leaf nodeN: The number of tags in the interrogation zoneL: The number of leaf nodes; ;
Proposed protocol Adaptive Identification-Tree Height Adjustment (cont’)
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Proposed protocol Adaptive Identification-Tree Height Adjustment (cont’)
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Proposed protocol Adaptive Identification-Tree Height Adjustment (cont’)
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Proposed protocol Adaptive Identification-Tree Height Adjustment (cont’)
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Proposed protocol Adaptive Identification-Tree Height Adjustment (cont’)
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Proposed protocol Adaptive Identification-Tree Height Adjustment (cont’)
Let the expected numbers of leaf nodes containing none, one and multiple tags be e(0), e(1) and e(m), respectively.
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Proposed protocol Adaptive Identification-Tree Height Adjustment (cont’)
It is reasonable to assume L>>1 and N>>1, and to take L–1 as L, and N–1, N–2 as N. We have
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
• Analyzing the ratio of the numbers of
leaf nodes that including zero tag, one tag
and multiple tags• The result of analysis
L : The number of leaf nodes N : The number of tags in the interrogation zone
Rule1
Rule2
Proposed protocol Adaptive Identification-Tree Height Adjustment (cont’)
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PS
Adaptive Computing and Networking Laboratory
WASN 2009• The Actions of Adjustment
Rule 1: If N0 > 2*N1 and N1 > 3.4*Nm,
=> all unidentified tags right-shift their counters one bit to divide L by 2.
Rule 2: If 2*N0 < N1 and 1.7*N1 < Nm
=> all unidentified tags left-shift their counters one bit to multiply L by 2, and subsequently add one or zero randomly to the counters.
Proposed protocol Adaptive Identification-Tree Height Adjustment (cont’)
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
• In phase IAll tags are split in parallel until the first tag is identified successfully.
• In phase IITags are identified one by one according to
The normal identification procedure of ISO/IEC 18000-6B protocol.
The reader applies Rule1 or Rule2 for adjusting the number of leaf nodes to approach the actual number N of tags (N is unknown)
• In phase II
Proposed protocol Two Phases of PS Protocol
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Outline
• Introduction• Anti-collision protocols• Proposed protocol • Evaluation• Conclusion
• Evaluation
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Evaluation
• The simulations are programmed
in Java language• Each simulation is performed 1,000 times
and then calculates the average value
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Evaluation
The comparison of the number of iterations for 1,025~2,025 tags.
-The relation between the height of the identification tree and the number of iterations needed
An iteration is defined as a reader sends a command and tags perform corresponding actions
N is the number of tags in the interrogation zone
is the “perfect” height of the identification-tree
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Evaluation-the number of iterations
The comparison of the number of iterations between ISO18000-6B and the PS protocol for 512~2,012 tags.
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Evaluation-System Efficiency
The comparison of PS, query tree (QT), ISO/IEC 18000-6B, and frame slotted ALOHA protocols in terms of system efficiency for 100~1,000 tags
System efficiency is defined as the ratio of the number N of tags to the number S of slots (iterations) required to identify all the tags
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Outline
• Introduction• Anti-collision protocols• Proposed protocol • Evaluation• Conclusion• Conclusion
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Conclusion
• We have proposed a newcounter based anti-collision
protocol (PS) for RFID systems• Two schemes are used in this protocol
parallel splitting
adaptive identification-tree height adjustment
• PS has better performance than ISO-18000 6B
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PS
Adaptive Computing and Networking Laboratory
WASN 2009
Thanks for Your Listening!
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