Author: Sytov, S.E.
Paper Title Page
WEPPD046 Digital Delay-Line Periodic FIR Filter Layout of Transverse Feedback in the U70 647
 
  • O.P. Lebedev, N.A. Ignashin, S.V. Ivanov, S.E. Sytov
    IHEP, Moscow Region, Russia
 
  A novel architecture of the wide-band transverse feedback system was successfully beam-tested in the U70 proton synchrotron of IHEP-Protvino. It employs a finite-time impulse response (FIR) non-recursive filter layout based on 3 (or 4, optionally) variable (–10%) multi-turn digital delay lines. Apart of using these natural-to-DSP components, the configuration involved has, at least, two operational advantages: (1) A single beam pickup layout plus acceptability of an arbitrary betatron phase advance between pickup and kicker. (2) A straightforward rejection of hampering DC and higher rotation frequency harmonic signals from beam position readouts. The latter occurs due to a periodic notch nature inherent in the amplitude-frequency in-out open-loop feedback transfer function. The paper reports on technical solutions implemented, problem-oriented R&D studies, and beam observations.