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Performance Improvement of STAC Protocol by Early Release of Reply Round and Transmission Probability Control

응답 라운드 조기종료와 전송확률 제어를 통한 STAC 프로토콜의 성능 개선

  • Lim, Intaek (Department of Embedded Software, Busan University of Foreign Studies)
  • Received : 2013.07.16
  • Accepted : 2013.08.19
  • Published : 2013.11.30

Abstract

In 13.56MHz RFID system of Auto-ID center, STAC protocol is defined as an anti-collision algorithm for multiple tag reading. In STAC protocol, the reader uses the tag number estimation scheme to determine the number of slots for the next reply round. If errors occur in the estimated number of tags, the identification performances will be degraded due to a lot of collision or idle slots. Therefore, in this paper, we propose an ERPB algorithm that the reader cancels the reply round when it experiences a series of collision or idle slots during the current round. The transmission probability control for the tag is also applied to the proposed algorithm. Through simulations, it is demonstrated that the collision rate for the proposed scheme is about 39% lower than STAC protocol. Therefore, the proposed scheme can achieve faster tag identification time compared with STAC protocol due to the low collision rate.

Auto-ID 센터에서는 13.56MHz RFID 시스템에서 다중 태그를 식별하기 위한 충돌 방지 알고리즘으로 STAC 프로토콜을 제안하였다. STAC 프로토콜에서는 다음 응답 라운드의 슬롯 개수를 결정하기 위하여 태그 수 추정 기법을 적용한다. 이 경우 추정한 태그의 수에 오차가 발생하면 충돌 또는 빈 슬롯이 많이 발생할 수 있으므로 식별 성능이 저하되는 문제점이 있다. 따라서 본 논문에서는 응답 라운드 동안 빈번한 충돌 또는 빈 슬롯이 발생하면 응답 라운드를 종료하는 기법과 태그의 전송확률을 제어하는 기법을 적용한 ERPB 알고리즘을 제안하고, 이에 대한 성능을 분석한다. 시뮬레이션을 통한 성능분석의 결과, 제안한 기법은 충돌률이 STAC 프로토콜에 비하여 39% 정도 낮으므로 태그 식별 시간이 짧음을 알 수 있었다.

Keywords

References

  1. H. Vogt, "Efficient Object Identification with Passive RFID Tags," First International Conf. on Pervasive Computing, LNCS, vol.2414, pp.99-113, Springer-Verlag, 2002.
  2. W. Chen, and G. Lin, "An Efficient Anti-Collision Method for Tag Identification in a RFID System," IEICE Trans Commun., vol.E89-B, no.12, pp.3386-3392, Dec. 2006. https://doi.org/10.1093/ietcom/e89-b.12.3386
  3. Auti-ID Center, "13.56MHz ISM Band Class 1 Rafio Frequency Identificatin Tag Interface Specification: Candidate Recommendation, Version 1.0.0," May 2003.
  4. Auto-ID Center, "860MHz-930MHz Class 0 Radio Frequency Identification Tag Protocol Specification Candidate Recommendation, Version 1.0.0," June 2003.
  5. B. Zhen, M. Kobayashi, and M. Shimizu, "Framed ALOHA for Multiple RFID Objects Identification," IEICE Trans. Commun., vol.E88-B, no.3, pp.991-999, Mar. 2005. https://doi.org/10.1093/ietcom/e88-b.3.991
  6. D. Lee, K. Kim, and W. Lee, "$Q^+$-Algorithm: An Enhanced RFID Tag Collision Arbitration Algorithm," Proc. UIC2007, LNCS, vol.4611, pp.23-32, Hong Kong, China, Jul. 2007.
  7. M. H. MacDaugall, Simulating Computer Systems Techniques and Tools, MIT Press, 1987.
  8. I. Lim, "A Scheme for Estimating Number of Tags in FSA-based RFID Systems," International Journal of KIMICS, vol.7, no.2, pp.164-169, June 2009.
  9. I. Lim, "Transmission Probability Control Scheme in FSA-based RFID Systems," International Journal of KIMICS, vol.8, no.6, pp.677-681, Dec. 2010. https://doi.org/10.6109/jicce.2010.8.6.677