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Distributed UORA Scheme for Autonomous Train Communication in Congested Environment

자율주행 열차의 혼잡 상황 통신을 위한 분산형 UORA 기법

  • Ahn, Woojin (Korea Railroad Research Institute) ;
  • Kim, Ronny Yongho (Department of Railroad Electrical & Electronic Engineering, Korea National University of Transportation)
  • 안우진 (한국철도기술연구원) ;
  • 김용호 (한국교통대학교 철도전기전자공학과)
  • Received : 2019.11.28
  • Accepted : 2019.12.27
  • Published : 2019.12.30

Abstract

Autonomous train is investigated to increase the capacity of railroad, and the reliability of wireless communication plays a critical role in terms of decreasing the inter-train distance. In this paper, we propose a transmission scheme for autonomous train communication in highly congested environment. The proposed scheme, namely distributed uplink orthogonal frequency division multiple access (OFDMA) random access (UORA), applies the triggered uplink access (TUA) and the UORA, introduced in the sixth generation WLAN standard, IEEE 802.11ax, for communication devices on vehicle and platform in a distributed manner. The simulation results show that the proposed scheme efficiently improves the packet transmission success rate in highly congested channel conditions compared to the conventional enhanced distributed channel access (EDCA) transmission scheme.

열차 자율주행은 제한된 열차 선로의 용량을 증가시키기 위한 미래 철도 기술이며, 무선통신의 안정성은 열차간 간격 감소에 있어서 핵심적인 역할을 한다. 본 논문에서는 자율주행열차 통신을 위한 혼잡 환경에서의 전송 기법을 제안하였다. 제안하는 분산 UORA (uplink OFDMA (orthogonal frequency division multiple access) random access) 기법은 최신 6세대 무선랜 표준인 IEEE 802.11ax의 TUA (triggered uplink access) 기법과 UORA 기법을 분산적으로 적용하여 혼잡도가 매우 높은 승강장 진입 환경에서, 승강장 및 차량의 센서가 효율적으로 차량 및 승강장의 수집 장치에게 전달할 수 있도록 한다. 본 논문의 실험 결과에 따르면, 제안하는 기법은 기존 EDCA (enhanced distributed channel access) 방식 대비 혼잡 상황에서 효과적으로 전송 성공률을 향상 시키는 것으로 나타났다.

Keywords

References

  1. T. Parkinson and I. Fisher, "Rail transit capacity," Transportation Research Board, Vol. 13, pp. 1-7, 1996.
  2. S. C. Oh et al., Detail plan for development of train autonomous-driving control core technology, Korea Railroad Research Institute, Aug. 2016.
  3. S. C. Oh et al., A study on the optimization of urban railway train operation system improvement for enhancing the safety and efficiency of train operation, Korea Railroad Research Institute, Oct. 2015
  4. S. H. Kim, "Current Status and Implications of domestic and international railway wireless network construction," KISDI Information & Communications Policy, Vol. 25, No. 9, pp. 1-44
  5. J. Goikoetxea, "Roadmap towards the wireless virtual coupling of trains," in Proceeding of International Workshop on Communication Technologies for Vehicles, San Sebastian: Spain, pp. 3-9, 2016.
  6. IEEE, Draft standard for information technology-telecommunications and information exchange between systems Local and metropolitan area networks-specific requirements, part 11: wireless LAN medium access vontrol (MAC) and physical layer (PHY) specifications, amendment 1: enhancements for high efficiency WLAN, IEEE P802.11ax/D5.1, 2019.
  7. D. Gross, Fundamentals of Queueing Theory, 4th ed. Hoboken, NJ: John Wiley & Sons, 2008.
  8. G. Bianchi, "Performance analysis of the IEEE 802.11 distributed coordination function," IEEE Journal on Selected Areas in Communications, Vol. 18, No. 3, pp. 535-547, March. 2000. https://doi.org/10.1109/49.840210
  9. W. Ahn, R. Y. Kim and Y. Y. Kim, "An energy efficient multi-user uplink transmission scheme in the next generation WLAN for internet of things," International Journal of Distributed Sensor Networks (Online Journal), pp. 1-9, May. 2016.