A Simulation Model for Industrial Multi-Channel Wireless Sensor Networks

Abstract

The use of Wireless Sensor Networks (WSN) in industrial environments is subject to problems, such as shadowing and fading. In addition, the wireless channel in many industrial environments is non-stationary for a long term, which can cause abrupt changes in the characteristics of the channel over time. A way to deal with those problems is the use of multi-channel protocols. However, it is difficult to evaluate, and compare different approaches because there is no reliable simulation model for industrial environments. This paper presents experimental results that characterize the wireless channel in industrial environments, and proposes a simulation model that captures the effects of fading, shadowing, and the non-stationary characteristics of the channel. It also considers the differences in the behavior of the different channels, and the asymmetry of the links. The model was integrated into the open source simulator Castalia. After the integration, two simulation studies were performed with the proposed model. In the first one, the Tree-based Multi-Channel Protocol was implemented and evaluated, and a comparison was made with the default model from Castalia. In the second case, CSMA/CA protocol, as defined in IEEE 802.15.4 standard, was compared to a protocol based on Time-Slotted Channel Hopping (TSCH) mode of IEEE 802.15.4e standard. The results showed that the use of TDMA and channel hopping is an alternative to deal with the problems of wireless channels in industrial environments.