The real-time orbit-position feedback system for the ELETTRA storage ring

To take full advantage of the low emittance and the small insertion-device source sizes, real-time global harmonic and local feedback systems have been designed for the Trieste synchrotron light source (ELETTRA). A fully digital approach has been chosen for data communication and processing, using VME as the standard system bus. The system architecture is presented, showing the open approach which allows a free choice in the use of beam-position monitors and correctors. The design considerations are given, pointing out the advantages in flexibility offered by the digital processing. (orig.)