Performance of the next timing and triggering system prototype for the XFEL project

The European XFEL project [1] requires a high-speed and high-quality clock and trigger distribution system. The main system frequency will be 1.3 GHz which will be distributed over a distance of more than 3.4 km, and all triggers will be related to it. All the clocks must have adjustable phases so that they can be kept in phase throughout the entire system. Distributing signals over such a long distance is quite challenging. All components are to some degree associated with drifts and additive jitter. Because of the systems extension, drifts in the fiber optics are significant and jitter is accumulated from the large number of components distributed over the system. The basic principles of the concept for the system were already tested in an early prototype board [2], which contained some key technologies, with very good results. The jitter performance was already better than the requirements stated and later even the drift compensation showed very good results. A new prototype board was designed and manufactured to study more features, while also being a fully functional system. Since the board was only available for a relatively short period, the measurements are initial and preliminary.