Installation and Evaluation of RFID Readers on Moving Vehicles

1. Installation and Evaluation of RFID Readers on Moving Vehicles VANET 2009 Eun Kyu Lee, Young Min Yoo, Chan Gook Park, Minsoo Kim, and Mario Gerla

2. Agenda • RFID applications • RFID-enabled vehicular applications • RFID system • RFID read performance • Installation of RFID system on vehicle • Road test • Conclusion

3. RFID Applications Supply Chain & Warehouse ePassport www.infoworld.com

4. Human implant RFID Applications www.wikipedia.org Automatic toll collection www.ezpass.com Smart payment www.ti.com

5. 2. Radio Frequency Identification (RFID) • RFID system review • RFID communication

6. Radio Frequency Identification (RFID) • What is RFID? • Identify physical objects • through a radio interface • Identification? • Assign ID to each object • Bar code, license plate, student ID • How does RFID work? • RFID tag + RFID reader + antenna • Backscattering coupling (UHF) Antenna Chip 02.3DFEX4.78AF51 EasyToll card #816

7. Radio Frequency Identification (RFID) • Tag type • Radio frequency range www.hitachi.com & www.vicariousconversations.com

8. RFID Communication • Framed slotted Aloha (FSA) A response from one RFID tag Slot .. .. . CW Query Cycle Power down CW Query Cycle Power down .. .. ..

9. 3. RFID in Vehicular Applications • RFID-enabled Vehicular Applications • On-board RFID reader system

10. RFID-enabled Vehicular Applications • Methodology of data producer/consumer • RFID tag • Stores data in memory, which is provided to RFID readers • A data producer • RFID reader • Obtains RFID data from tags and utilizes it for further programs • A data consumer Each vehicle is a data producer !!

11. RFID-enabled Vehicular Applications cs.rutgers.edu • Tag on vehicle (data producer) • Readers are on the roadside • Automatic toll collection • Intelligent traffic signal system • Electronic license plate • Priority lane management • Lane reservation and enforcement Reservation/ Enforcement System www.ti.com Enforce Enforce Reserve Reserve RFID Reader/ Camera Low-Priority Lanes Lane Entrance Assistance System High-Priority Lane

12. RFID-enabled Vehicular Applications • Reader on vehicle (data consumer) • Tags on the roadside units (road surface, sign post, direction sign) • RFID positioning and Road beacon system (RBS) • Lane-level GPS (Donath’06) • RFID tags along each lane contains useful data (e.g., position) • Intersection collision avoidance, • Enhancement of driver’s situation awareness, • Lane by lane incident management RFID reader RFID tag

13. RFID-enabled Vehicular Applications • Tag/reader on vehicle (data prosumer) • Intelligent priority lane management • Peer localization RFID tag RFID reader

14. On-board RFID Reader System • Challenges • High vehicle speed • Faster than 100Km/h on a freeway • Short communication distance • Much less chance of RFID communication • Random mobility of reader • Reader position affects performance significantly than tag placement • Random fading effects 0.3m RFID tag 3m~4m RFID reader

15. On-board RFID Reader System • Motivation • Initial deployment of RFID reader/tag is important for better performance • Necessary to measure performance in a real test road • In this work, we • Install RFID reader on a vehicle and tags on a road surface • Evaluate RFID read performance in a laboratory environment • Propose antenna diversity and tag multiplicity for improvement • Conduct a road test to study feasibility of the system

16. 4. Understand RFID Read Rate • Specification of the RFID system • RFID performance • RFID read area • Read latency • RFID read rate

17. RFID System

18. RFID Performance • RFID read area • Size and moving speed Moving speed of RFID area RFID read area For instance, if h=37.5cm and θ=45°, then X1=58.58cm and X2=185.63cm Measured X2≒100cm (1m) RFID communication should occur in 1m read area within 36m

19. RFID Performance • Read latency • Time period when one RFID communication occurs • Measured 38.39ms on average • Mostly due to the maximum pause time of the tag: 62.5ms • However, • RFID read area moves at 36ms > 38.39ms • Even 60ms at 60km/h < 62.5ms • RFID read rate High possibility of RFID communication failure <- 36ms 38.39ms # of tags successfully read = ----------------------- total # of tags deployed

20. Laboratory Experiment • Experiment setup • RFID reader antenna • Height • Pitch angle • Antenna diversity • RFID tag • Yaw angle • Pitch angle • Tag multiplicity • Result

21. Laboratory Experiment • Target performance • 0.5m of read area and 18m of read latency • Height of RFID reader antenna h=30cm • Similar performance in h=20~40cm • Height of the test vehicle is 30cm • Installation • RFID reader antenna & RFID tag 18ms of read latency RFID reader antenna RFID tag 30°of tag yaw angle and 30°of antenna pitch angle 0.5m

22. RFID Reader Antenna • Pitch angle • Varying pitch angle of the antennas • Measure the read area given 18ms of read latency • 30° of pitch angle RFID tags are attached on the floor with 0°

23. RFID Reader Antenna RFID Tag 80 cm 78 cm • Antenna diversity • Install one and dual antenna(s) • Measure the read area given 18ms of read latency 43 cm 65 cm RFID Reader Antenna RFID Reader Antenna 2 RFID Reader Antenna 1 1.5m 3m 1 Antenna 2m 0.86m 2 Antennas 1.3m RFID Tag

24. RFID Tag • Yaw angle and pitch angle • Measure the read latency given 0.5m of the read area • Both are set 0° 30° of reader antenna

25. RFID Tag • Tag multiplicity • To mitigate effect of the random pause time • Measure the read latency given 0.5m of the read area • Cluster model 3 having 3 or 4 member tags Cluster 4 Cluster 2 Cluster 3 Cluster 1

26. Results • RFID communication successfully occurs within 0.8m of RFID read area and 18ms of read latency • Antenna diversity and tag multiplicity • Showed improved performance • Estimation of the maximum vehicle speed • At which RFID communication can occur • 161.7km/h • Equivalent to previous researches

27. Road Test • Test road configuration • Effect of antenna diversity • Effect of tag multiplicity

28. Server Test Road RFID Reader RFID Tag RFID Reader Antenna Test scenarios with variables Deployment parameters

29. Road Test • Effect of antenna diversity • Proof of concept in terms of width • Reduced length does not affect performance much Average duplication read 1 Antenna 1.5m 3m 2m 0.86m Average read rate 1.3m RFID Tag 2 Antennas

30. 1 Tag, 2m Interval (Test 2) 1 Tag, 2m Interval (Test 2) Road Test 3 Tags, 2m Interval (Test 3) 3 Tags, 2m Interval (Test 3) 4 Tags, 2m Interval (Test 4) 4 Tags, 2m Interval (Test 4) 3 Tags, 5m Interval (Test 5) 3 Tags, 5m Interval (Test 5) 4 Tags, 5m Interval (Test 6) 4 Tags, 5m Interval (Test 6) 100 30 Average Duplication Read [number] • Effect of tag multiplicity • Tag cluster outperforms single tag (Test 2, 3, and 4) • Tag interval influences performance (Test 3 and 5) • In particular, at high speed • Duplication read dramatically decreases at high speed 90 25 80 70 20 60 50 15 40 10 30 Vehicle Speed [km/h] Average duplication read 20 5 10 0 0 10 20 30 40 50 60 70 80 90 100 10 20 30 40 50 60 70 80 90 100 Average Read Rate [%] Vehicle Speed [km/h] Average read rate

31. Conclusion • Summary • RFID-enabled vehicular applications • On-board RFID reader system • Experiment • In a laboratory • RFID reader antenna and RFID tag • On a test road • Contribution • A different approach to RFID-enabled vehicular system • Address antenna diversity and tag multiplicity • The newest topics for performance improvement • Experiment data from a real test bed

32. Thank you VANET 2009