Sub-??s synchronization accuracy in distributed measurement system by PDA and PC triggers realignement

This paper deals with the synchronization of the measurement instruments cooperating in the distributed measurement system interfaced to the network node by wireless devices, Personal Digital Assistants or PC. The different hardware and software architecture of the wireless devices and PCs delays the triggering of the measurement instruments in unpredictable wide range that introduces a new problem respect to the case the node interfaces are all PCs or all wireless devices. The paper proposes the use of the Embedded Synchronizing Hardware (ESH) as middleware between the node interfaces and the measurement instruments to align the trigger signals. Suitably setting procedure of the ESH is pointed out based on the probability reduction that the unpredictable wide range of the delay occurs. Experimental results validate the suitability of the ESH to reach the sub-μs synchronization accuracy without dependence from the node interface.