A distributed algorithm to schedule TSCH links under the SINR model

Abstract

Industrial environments are typically characterised by high levels of interference. Therefore, standards for industrial wireless sensor networks (WirelessHART, ISA 100.11a, and IEEE 802.15.4e) have defined a time division and multichannel-based mode of operation, in which pairs of time slots and channels are assigned to links representing communication between nodes. In IEEE 802.15.4e this mode of operation is called Timed Slotted Channel Hopping. In this paper we describe a distributed algorithm to define such an assignment for a given network. The algorithm is efficient, scalable and was developed for the Signal-to-Interference-plus-Noise-Ratio model, currently considered the most appropriate to analyse algorithms for wireless networks when interference is taken into consideration. In particular, the algorithm provides deterministic communication in the network. Previous approaches to this problem are mainly centralised, based on a simple (or none) interference model, do not provide deterministic communication or do not consider multiple physical channels. In this paper we describe the algorithm and present results of simulation, where we evaluated the number of rounds needed for computing the schedules and the size of the produced schedules. The described algorithm applies also to the Internet of Things, characterised by high scale and presence of interference.