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)


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.


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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

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