Theoretical and experimental evaluation of polling times for wireless industrial networks using commercially available components

In the last years, several wireless standards have been profitably tested for possible application in factory communication systems, showing encouraging results even in time-critical applications. However, the achieved performance are clearly related to the specific applications considered and, more important, to the specific wireless components employed. In this paper, we consider the wireless extension of a very popular Real-Time Ethernet network, Ethernet Power-link, and we propose a practical implementation of it based on commercially available IEEE 802.11 Access Points. We first provide a theoretical analysis of the expected polling times and then we compare the obtained results with the outcomes of some experimental sessions carried out on a prototype installation, in order to characterize the behavior of the employed devices.