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  • Open Access

Modern signal processing techniques for efficient transverse feedback systems operation in hadron accelerators

Gerd Kotzian, Xavier Buffat, and Jani Komppula

Viera Stopjakova

Daniel Valuch*

  • Accelerator Systems Department, CERN, Geneva, Switzerland

  • *Contact author: transverse-feedbacks@cern.ch
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Phys. Rev. Accel. Beams 28, 102801 – Published 28 October, 2025

DOI: https://doi.org/10.1103/szv9-nfd5

Abstract

Transverse feedback systems are essential for stable operation of all hadron accelerators with high intensity beams. An important component of such a system is a powerful digital signal processing unit. Current digital technology enables the implementation of advanced algorithms to process signals and analyze key parameters of both the accelerator and its feedback systems. In the paper, we present a new digital filter, which is suitable for the construction of a single pickup feedback with a larger tune acceptance and higher gain than can be achieved by the traditionally used Hilbert phase-shifter technique. We propose a method to extract key parameters required for optimal feedback operation, such as the closed-loop phase and delay, as well as accelerator parameters like bunch-by-bunch damping time and machine tune. This is achieved solely through active manipulation of the beam by the transverse feedback system and its analysis of acquired data. Accurate knowledge of these parameters is essential for ensuring beam stability and the reliable operation of the accelerator. Easy access to them is important for automated TFB setting up, performance monitoring, or efficient troubleshooting.

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Phys. Rev. Accel. Beams 28, 102801– Published 28 October, 2025
  • Received 2 January 2025
  • Accepted 25 September 2025
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