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LoS 및 NLoS 환경에서의 경로 손실을 고려한 LoRa의 모의실험 및 실측 결과 분석

Analysis of Computer Simulated and Field Experimental Results of LoRa Considering Path Loss under LoS and NLoS Environment

  • Yi, Dong Hee (Pusan National University, Department of Electrical and Computer Engineering) ;
  • Kim, Suk Chan (Pusan National University, Department of Electrical and Computer Engineering)
  • 투고 : 2017.01.17
  • 심사 : 2017.02.07
  • 발행 : 2017.02.28

초록

최근 사물인터넷 (IoT; Internet-of-things)의 필요성이 급격하게 대두됨에 따라 Low Power Wide Area (LPWA) 표준에 대한 관심이 커지고 있다. 이 논문에서는 LPWA의 표준 중의 하나인 LoRa 기술에 대한 성능을 실측 데이터에 기반하여 분석한다. 특히, Line-of-sight (LoS) 및 Non-line-of-Sight (NLoS) 환경에서 수신 신호의 Received Signal Strength Indication (RSSI) 값을 측정하여 이론적인 경로손실 모형을 적용한 RSSI 값과 비교한다. 이를 위해 다양한 경로손실 모형 중에서 Log-distance 및 Two-ray 모형 그리고 실측 데이터에 기반한 통계적 모형인 Okumura-Hata 모형을 적용한다. 그 결과, LoS 및 NLoS 환경 모두에서 Okumura-Hata 모형이 RSSI 실측 데이터와 가장 근접한 것으로 분석되었다. 이러한 결과는 LoRa를 이용하여 네트워크를 구성할 때 최적의 노드 배치를 위한 기준을 제공하는데 활용될 수 있을 것이다.

Recently, a demand of Internet-of-things (IoT) rises dramatically and an interest in Low Power Wide Area (LPWA) grows larger accordingly. In this paper, performance in LoRa which is included in LPWA standard is analyzed. Particularly, after measuring Received Signal Strength Indication (RSSI) of received signal on Line-of-sight (LoS) and Non-line-of-sight (NLoS) environment and it is compared with RSSI which theoretical path loss model is applied to. Among many path loss models, the simulation for theoretical RSSI use Log-distance, Two-ray model and Okumura-Hata model that is based on the test database. Consequently, the result of Okumura-Hata model is the most similar with the measured RSSI. When a network based on LoRa is built, this result can used to decide optimal node arrangement.

키워드

참고문헌

  1. C.-S. Oh, et al., "Indoor air quality monitoring systems in the IoT environment," J. KICS, vol. 40, no. 5, pp. 886-891, May 2015. https://doi.org/10.7840/kics.2015.40.5.886
  2. S. B. Lee, et al., "A study on the development of platform based on IoT," in Proc. KICS Int. Conf. Commun., pp. 1059-1061. Jeju Island, Korea, Jun. 2016.
  3. J. Park, "Technology and Issue on embodiment of smart factory in small-medium manufacturing business," J. KICS, vol. 40, no. 12, pp. 2491-2502, Dec. 2015. https://doi.org/10.7840/kics.2015.40.12.2491
  4. Semtech Corporation, LoRa TM Modulation Basics(2015), Retrieved Dec. 20, 2016, from http://www.semtech.com.
  5. Andrea Goldsmith, Wireless communications, Cambridge, 2004.
  6. M. Bae, et al., "Measurement and analysis of LOS-based path loss in urban wireless sensor network environments," J. KISS : Inf. Netw., vol. 38, no. 5, pp. 411-416, Oct. 2011.
  7. M. Hata, "Empirical formula for propagation loss in land mobile radio services," IEEE Trans. Veh. Technol., vol. VT-29, no. 3, pp. 317-325. Aug. 1980.
  8. Sylvain Ranvier, Path Loss Models(2004), Retrieved from http://www.comlab.hut.fi.
  9. S. Y. Kim, et al., "Wide range IoT technology and standardization based on LPWA," Electron. Telecommun. Trends, vol. 31, no. 2, pp. 95-106, Apr. 2016.
  10. A. Springer, et al., "Spread spectrum communications using chirp signals," IEEE/ AFCEA EUROCOMM 2000, Inf. Syst. Enhanced Public Safety and Security, pp. 166-170, May 2000.xs
  11. LoRa Alliance, LoRaWAN Specification (2015), Retrieved Dec. 26, 2016, from https://www.lora-alliance.org.
  12. Semtehch Coperation, SX1276/77/78/79 - 137 MHz to 1020 MHz Low Power Long Range Transceiver(2015), Retrieved Dec. 20, 2016, from http://www.semtech.com.
  13. Ministry of Science, ICT and Future Planning, Rules on Radio Equipment(2015), Retrieved Dec. 20, 2016, from http://www.msip.go.kr.
  14. W. C. Huffman and V. Pless, Fundamentals of Error-Correcting Codes, Cambridge, 2003.

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  2. Propagation Map Interpolation Scheme for Identifying Received Signal Strength Shading Areas in Spectrum Management System Based on Block Chain vol.30, pp.9, 2017, https://doi.org/10.5515/kjkiees.2019.30.9.718