Master’s Thesis in Computer Systems Engineering
Integration of Positioning Capabilities into an existing active RFID System
Andreas FranzWolfgang JohnPhilipp Nagele
Supervisor: Per-Arne Wiberg
Halmstad, 4th June 2004
Integration of Positioning Capabilities into an existing RFID System
2/16
Overview
• General apsects• Project objectives• System concept• Positioning algorithm• Simulation results• Use case
Integration of Positioning Capabilities into an existing RFID System
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Project Objective
• Enhancing the existing RFID system with positioning functionalities
• Designing a concept for - an indoor communication protocol- a positioning algorithm on a central back-end
system• Implementing the proposed algorithm• Proving the feasibility by simulations• Analysing system characteristics
Integration of Positioning Capabilities into an existing RFID System
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System Components
• Tag - saves received angular data (AoA)
• Reader- collects data from tags - forwards data to the backend system
• Directional Unit (DU)- provides angular information (AoA)
• Backend system (PC)- computes positioning algorithm
Integration of Positioning Capabilities into an existing RFID System
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Communication Protocol
DU 1
DU 2
DU 3
DU 4
f
t21
Tag Memory:
DU 1 | 85° | 1 |DU 2 | 225° | 2 |
Reader
Backend system
45280
85225
Integration of Positioning Capabilities into an existing RFID System
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Communication Protocol
DU 1
DU 2
DU 3
DU 4
f
t4321
Tag Memory:
DU 1 | 85° | 1 |DU 2 | 225° | 2 |DU 3 | 46° | 3 |
Reader
Backend system
46281
86226
Integration of Positioning Capabilities into an existing RFID System
7/16
Communication Protocol
DU 1
DU 2
DU 3
DU 4
f
t4321 5 6
Tag Memory:
DU 1 | 85° | 1 |DU 2 | 225° | 2 |DU 3 | 46° | 3 |DU 2 | 227° | 6 |
Reader
Backend system
47
282
87227
Integration of Positioning Capabilities into an existing RFID System
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Communication Protocol
DU 1
DU 2
DU 3
DU 4
f
t4321 5 6
Tag Memory:
DU 1 | 85° | 1 |DU 2 | 225° | 2 |DU 3 | 46° | 3 |DU 2 | 227° | 6 |DU 3 | 48° | 7 |DU 4 | 283° | 8 |
Reader
Backend system
48
283
88 228
7 8
Integration of Positioning Capabilities into an existing RFID System
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Positioning Algorithm
Integration of Positioning Capabilities into an existing RFID System
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Example
Integration of Positioning Capabilities into an existing RFID System
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Simulation of the Protocol
• Communication protocol modelled in Matlab
• Modular design- Free DU placement- Variable multipath and propagation effects- Adjustable system parameters
• Optimisation of system parameters• Power consumption• Memory considerations
Integration of Positioning Capabilities into an existing RFID System
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Use Case
req. Accuracy
Multipath Effects
DU/ 100m2
Assembling Area
Low -Proximity
Medium 0,375
Warehouse
Medium - Palette
High 0,9375
Loading Zone
High - Goods
Low 3
Integration of Positioning Capabilities into an existing RFID System
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Use Case
req. Accuracy
Multipath Effects
DU/ 100m2
Assembling Area
Low -Proximity
Medium 0,375
Warehouse
Medium - Palette
High 0,9375
Loading Zone
High - Goods
Low 3
Integration of Positioning Capabilities into an existing RFID System
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Use Case
req. Accuracy
Multipath
DU/ 100m2 Mean Error
Assembling Area
Low Medium 0,375 77.0 cm
Warehouse Medium High 0,9375 55.1 cmLoading Zone High Low 3 20.6 cm
Integration of Positioning Capabilities into an existing RFID System
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Conclusion
• Positioning achieved with minor hardware adaptations
• Implementation of a positioning algorithm- Plausibility weighting
• High scalability due to flexible DU placement
• Promising accuracy results for a future experimental setup
Integration of Positioning Capabilities into an existing RFID System
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Thank you for your attention!