Advertisement

Impact of Spreading Factor Imperfect Orthogonality in LoRa Communications

  • Daniele CroceEmail author
  • Michele Gucciardo
  • Ilenia Tinnirello
  • Domenico Garlisi
  • Stefano Mangione
Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 766)

Abstract

In this paper we study the impact of imperfect-orthogonality in LoRa spreading factors (SFs) in simulation and real-world experiments. First, we analyze LoRa modulation numerically and show that collisions between packets of different SFs can indeed cause packet loss if the interference power received is strong enough. Second, we validate such findings using commercial devices, confirming our numerical results. Third, we modified and extended LoRaSim, an open-source LoRa simulator, to measure the impact of inter-SF collisions and fading (which was not taken into account previously in the simulator). Our results show that non-orthogonality of the SFs can deteriorate significantly the performance especially of higher SFs (10 to 12) and that fading has virtually no impact when multiple gateways are available in space diversity.

References

  1. 1.
    Worldwide connected devices forecast. www.statista.com
  2. 2.
    Semtech: LoRa Modulation Basics. AN1200.22, Revision 2, May 2015. www.semtech.com
  3. 3.
    Bor, M.C., Roedig, U., Voigt, T., Alonso, J.M.: Do LoRa low-power wide-area networks scale? In: Proceedings of MSWiM 2016, pp. 59–67 (2016)Google Scholar
  4. 4.
    Reynders, B., Pollin, S.: Chirp spread spectrum as a modulation technique for long range communication. In: SCVT 2016, Mons, pp. 1–5 (2016)Google Scholar
  5. 5.
    Reynders, B., Meert, W., Pollin, S.: Range and coexistence analysis of long range unlicensed communication. In: ICT 2016, Thessaloniki, pp. 1–6 (2016)Google Scholar
  6. 6.
  7. 7.
    Vangelista, L., Zanella, A., Zorzi, M.: Long-range IoT technologies: the dawn of LoRa. In: Atanasovski, V., Leon-Garcia, A. (eds.) FABULOUS 2015. LNICSSITE, vol. 159, pp. 51–58. Springer, Cham (2015). doi: 10.1007/978-3-319-27072-2_7 CrossRefGoogle Scholar
  8. 8.
    Augustin, A., Yi, J., Clausen, T., Townsley, W.: A study of LoRa: long range & low power networks for the Internet of Things. Senors 16(9), 1466 (2016)Google Scholar
  9. 9.
    Bankov, D., Khorov, E., Lyakhov, A.: On the limits of LoRaWAN channel access. In: 2016 International Conference on Engineering and Telecommunication (EnT), Moscow, pp. 10–14 (2016)Google Scholar
  10. 10.
    Knight, M., Seeber, B.: Decoding LoRa: realizing a modern LPWAN with SDR. In: Proceedings of the GNU Radio Conference, [S.l.], v. 1, n. 1, September 2016Google Scholar
  11. 11.
    Sornin, N., Luis, M., Eirich, T., Kramp, T., Hersent, O.: Lorawan specification v1.0, Technical report, LoRa Alliance, Technical report (2015)Google Scholar
  12. 12.
    Bernard, O., Seller, A., Sornin, N.: Low power long range transmitter. European Patent Application EP 2763321 A1 by Semtech Corporation (2014)Google Scholar
  13. 13.
    Goursaud, C., Gorce, J.M.: Dedicated networks for IoT: PHY/MAC state of the art and challenges. In: EAI Endorsed Transactions on Internet of Things (2015)Google Scholar
  14. 14.
    Semtech Corporation: LoRa SX1272/73 transceiver datasheet (2015)Google Scholar
  15. 15.
    SimPy event discrete simulation for Python. https://simpy.readthedocs.io

Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Daniele Croce
    • 1
    • 2
    Email author
  • Michele Gucciardo
    • 1
  • Ilenia Tinnirello
    • 1
  • Domenico Garlisi
    • 1
    • 2
  • Stefano Mangione
    • 1
  1. 1.DEIMUniversità di PalermoPalermoItaly
  2. 2.CNIT ConsortiumParmaItaly

Personalised recommendations