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arXiv · 1809.06104

TDMH-MAC: Real-time and multi-hop in the same wireless MAC

Federico Terraneo·Paolo Polidori·Alberto Leva·William Fornaciari
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Abstract

Supporting real-time communications over Wireless networks (WSNs) is a tough challenge, due to packet collisions and the non-determinism of common channel access schemes like CSMA/CA. Real-time WSN communication is even more problematic in the general case of multi-hop mesh networks. For this reason, many real-time WSN solutions are limited to simple topologies, such as star networks. We propose a real-time multi-hop WSN MAC protocol built atop the IEEE 802.15.4 physical layer. By relying on precise clock synchronization and constructive interference-based flooding, the proposed MAC builds a centralized TDMA schedule, supporting multi-hop mesh networks. The real-time multi-hop communication model is connection-oriented, sing guaranteed time slots, and enables point-to-point communications also with redundant paths. The protocol has been implemented in simulation using OMNeT++, and the performance has been verified in a real-world deployment using Wandstem WSN nodes.

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Federico Terraneo, Paolo Polidori, Alberto Leva, William Fornaciari. 2018-09-17. TDMH-MAC: Real-time and multi-hop in the same wireless MAC. https://arxiv.org/abs/1809.06104

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