IEEE 802.11e in Industrial Environments: a Quality of Service Survey

The communication between control units and field devices in industrial environments is based on so-called fieldbus technologies networks optimized for the realtime transmission of highly sensitive data for control and monitoring purposes. As a strong need for wireless fieldbus systems arose, the applicability of available wireless standards has been examined. Some specialized wireless systems are arising on the market but so far, no appropriate general solution based on a common standard could be found. In this project, the upcoming standard IEEE 802.11e is analyzed and its applicability tested by means of simulations in the network simulator ns-2. Several traffic scenarios, typical for communications in the automation industry are considered. In order to enhance the achievable performance in an error-prone environment, different algorithms and retransmission procedures are proposed. The obtained results show that, even though IEEE 802.11e is not optimized for industrial applications, it has a potential for realtime applications with some jitter and error margins.