Simulation and assessment of wireless fieldbus networks over IEEE802.11

The recent improvement of wireless communication networks has made possible the use of such networks at the lowest levels of factory automation systems, which typically imposes severe requirements in terms of both real-time performance and dependability. However, Industrial plants represent a hostile environment, for communication systems, due to the presence of different kind of noises. The presence of these noises can easily inflict damages on the wireless information signals and creates erroneous interruptions on the data transmitted. In most wireless industrial systems, such errors and interferences are modelled by AWGN and Gilbert-Elliot models. In this paper, we have attempted to assess the performance of the wireless fieldbus network on the aforementioned channels in order to evaluate the potential performance of AWGN and its comparison with the Gilbert-Elliot channel. Furthermore, the handling of asynchronous alarm packets is done by considering two methods of Late and Immediate technique. The NS2 simulation results have proved the superior performance of AWGN model in comparison with Gilbert — Elliot model.