Hybrid CSMA/CA for Sub-1 GHz Frequency Band Coexistence of IEEE 802.11ah and IEEE 802.15.4g

    •  Guo, J., Nagai, Y., Sumi, T., Orlik, P.V., Yamauchi, T., "Hybrid CSMA/CA for Sub-1 GHz Frequency Band Coexistence of IEEE 802.11ah and IEEE 802.15.4g", International Workshop on Informatics (IWIN), September 2020.
      BibTeX TR2020-127 PDF
      • @inproceedings{Guo2020sep,
      • author = {Guo, Jianlin and Nagai, Yukimasa and Sumi, Takenori and Orlik, Philip V. and Yamauchi, Takahisa},
      • title = {Hybrid CSMA/CA for Sub-1 GHz Frequency Band Coexistence of IEEE 802.11ah and IEEE 802.15.4g},
      • booktitle = {International Workshop on Informatics (IWIN)},
      • year = 2020,
      • month = sep,
      • url = {}
      • }
  • MERL Contacts:
  • Research Areas:

    Communications, Optimization, Signal Processing


As more and more wireless technologies have been developed to support emerging IoT applications, the coexistence of heterogeneous wireless technologies presents challenges. IEEE 802.11ah and IEEE 802.15.4g are two of such wireless technologies specified for outdoor IoT applications. Due to the constrained spectrum allocation in the Sub-1 GHz (S1G) band, these two types of devices may be forced to coexist, i.e., share frequency spectrum. To investigate coexistence behavior of 802.11ah and 802.15.4g, we first identify coexistence issues using our newly developed NS-3 based S1G band coexistence simulator. Accordingly, we propose a hybrid CSMA/CA mechanism for 802.15.4g to address the identified coexistence issues. The conducted performance analysis shows that the proposed hybrid CSMA/CA improves 802.15.4g performance without degrading 802.11ah performance. The hybrid CSMA/CA also maintain overall 802.11ah packet latency.


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