Foundation Fieldbus H1 physical layer diagnosis improvement

Fieldbus networks have been widely used for process controlling, automation and many other applications. These types of network designed to work reliably and timely. But Fieldbuses usually works under harsh conditions which can degrade the expected features. Quality of communication on the links can be decreased in these environments and cause to physical layer malfunction. In order to detect such degradations, physical layer diagnostic systems have been developed. In this paper present systems have been investigated and tried to improve them. For improvement, two suggestions have been offered; moving the system and using new diagnostic parameter. We have examined the performance of previous and proposed diagnostic parameters for the first time and found significant improvements.