On the Integration of FieldBus Traffic within IEEE802.11 Wireless LAN

In various process control environments in which FieldBus communication systems are widely used it is often necessary to interconnect them. Unfortunately this interconnection raises several issues that the solutions found so far have not been able to solve satisfactorily. In this paper we propose the use of a wireless LAN based on the IEEE 802.11 draft standard as a backbone system. Suitable modifications are introduced in this draft standard in order to meet FieldBus communication requirements. The problems of integrating the traffic generated by FieldBus systems, which notoriously is featured by urgent time constraints, are dealt with and solved by proposing a simply achieved modification to the 802.11 MAC protocol. Through simulation analysis we then present a performance evaluation of the interconnection system and the cost of the modification proposed.