Journal of the Korea Institute of Information and Communication Engineering (한국정보통신학회논문지)

The Korea Institute of Information and Commucation Engineering (한국정보통신학회)
권호 표지
DOI QR코드

DOI QR Code

Exploiting Spatial Reuse Opportunity with Power Control in loco parentis Tree Topology of Low-power and Wide-area Networks

대부모 트리 구조의 저 전력 광역 네트워크를 위한 전력 제어 기반의 공간 재사용 기회 향상 기법

  • Byeon, Seunggyu (Department of Artificial Intelligence, Silla University) ;
  • Kim, Jong Deok (School of Computer Science and Engineering, Pusan National University)
  • Received : 2021.11.26
  • Accepted : 2021.12.25
  • Published : 2022.02.28
Download PDF
⟨ Previous Next ⟩

Abstract

LoRa is a physical layer technology designed to secure highly reliable long-range communication with introducing loco parentis tree network and chirp spreading spectrum. Since since a leaf can send message to more than one parents simultaneously with a single transmission in a region, packet delivery ratio increases logarithmically as the number of gateways increases. The delivery ratio, however, dramatically collapses even under loco parentis tree topology due to the limitations of ALOHA-like primitive MAC, . The proposed method is intended to exploit SDMA approach to reuse frequency in an area. With the view, TxPower of each sender for each message in a concurrent transmission is elaborately controlled to survive the collision at different gateway. Thus, the gain from the capture effect improves the capacity of resource-hungry Low Power and Wide Area Networks.

LoRa는 네트워크에 대부모 트리 구조와 처프 확산 스펙트럼을 도입한 물리 계층 기술로 높은 신뢰도의 장거리 통신을 제공한다. LoRa의 트리 네트워크에서 자식 노드는 단일 부모가 아닌 여러 노드에게 동시에 메시지를 전송할 수 있기 때문에 동일 부하가 네트워크에 가해진다면 패킷 전달률은 게이트웨이의 수의 증가에 따라 증가한다. 하지만 알로하류의 원시적 매체 접근 제어의 한계 때문에 이러한 트리 환경에서도 부하의 증가에 따라 네트워크의 이용률은 하락한다. 본 논문에서는 동일 주파수를 동일 시간대, 동일 지역에서 사용하는 공간 분할 다중 접근 방식을 제안한다. 본 기법은 수집된 신호 세기의 분포로부터 송신 전력을 도출하여 같은 시간, 다른 게이트웨이에서 각기 다른 패킷이 수신되도록 제어한다. 즉, 포획 효과를 의도적으로 활용하여 저전력 광역 네트워크의 노드 수용력을 향상시킨다.

Keywords

References

  1. M. C. Bor, T. Voigt, and J. M. Alonso, "Do LoRa low-power wide-area networks scale?," in Proceedings of the 19th ACM International Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems, ACM, Malta, pp. 59-67, Nov. 2016.
  2. M. C. Bor, J. Vidler, and U. Roedig, "LoRa for the Internet of Things," in Proceedings of the 2016 International Conference on Embedded Wireless Systems and Networks, Graz: Austria, pp. 361-366, Jan. 2016.
  3. A. I. Pop, U. Raza, P. Kulkarni, and M. Sooriyabandara, "Does bidirectional traffic do more harm than good in LoRaWAN based LPWA networks?," in GLOBECOM 2017-2017 IEEE Global Communications Conference, Singapore, pp. 1-6, Dec. 2017.
  4. B. Vgaard, M. Lauridsen, H. Nguyen, I. Z. Kovacs, P. Mogensen, and M. Sorensen, "Interference impact on coverage and capacity for low power wide area IoT networks," in Wireless Communications and Networking Conference (WCNC), San Francisco: CA, pp. 1-6, Mar. 2017.
  5. O. Georgiou and U. Raza, "Low power wide area network analysis: Can LoRa scale?," IEEE Wireless Communications Letters, vol. 6, no. 2, pp. 162-165, Apr. 2017. https://doi.org/10.1109/LWC.2016.2647247
  6. A. Augustin, J. Yi, T. Clausen, and W. M. Townsley, "A study of LoRa: Long range & low power networks for the internet of things," Sensors, vol. 16, no. 9, pp. 1466, May. 2016. https://doi.org/10.3390/s16091466
  7. J. Petajajarvi, K. Mikhaylov, A. Roivainen, T. Hanninen, and M. Pettissalo, "On the coverage of LPWANs: range evaluation and channel attenuation model for LoRa technology," in 14th International Conference on ITS Telecommunications (ITST), Copenhagen, pp. 55-59, Dec. 2015.
  8. T. Voigt, M. Bor, U. Roedig and J. Alonso, "Mitigating inter-network interference in LoRa networks," in Proceedings of the 2017 International Conference on Embedded Wireless Systems and Networks, Uppsala, pp. 323-328. Feb. 2017.
  9. D. Croce, M. Gucciardo, S. Mangione, G. Santaromita, and I. Tinnirello, "Impact of LoRa imperfect orthogonality: Analysis of link-level performance," IEEE Communications Letters, vol. 22, no. 4, pp. 796-799, Jan. 2018. https://doi.org/10.1109/lcomm.2018.2797057
  10. C. Isensee and G. Horton, "Approximation of discrete phase-type distributions," in Proceedings of IEEE 38th Annual Simulation Symposium, San Diego: CA, pp. 99-106, Apr. 2005.
  11. Y. Hasegawa and K. Suzuki, "A Multi-User ACK-Aggregation Method for Large-Scale Reliable LoRaWAN Service," in ICC 2019-2019 IEEE International Conference on Communications (ICC), Shanghai, pp. 1-7, May. 2019.
  12. LoRa Alliance [Online]. Available: https://lora-alliance.org/.
  13. SEMTECH. LoRa End Devices and Indoor/Outdoor Gateway Specification and Parameters [Online]. Available: https://www.semtech.com/.