Tune Evaluation From Phased BPM Turn-By-Turn Data
  In fast ramping synchrotrons like the Fermilab Booster the conventional methods of betatron tune evaluation from the turn-by-turn data may not work due to rapid changes of the tunes (sometimes in a course of a few dozens of turns) and a high level of noise. We propose a technique based on phasing of signals from a large number of BPMs which significantly increases the signal to noise ratio. Implementation of the method in the Fermilab Booster control system is described and some measurement results are presented. 
Y. Alexahin, E. Gianfelice-Wendt, W. Marsh (Fermilab)
physics.acc-ph