IPAC2018 - List of Authors (Moreno Arostegui, J.M.M.A.)

Paper	Title	Page
THPML121	Compensation of Transient Beam Loading in Ramping Synchrotrons Using a Fixed Frequency Processing Clock	4957
SUSPL061	use link to see paper's listing under its alternate paper code
	F.J. Galindo Guarch, J.M.M.A. Moreno Arostegui Universitat Politécnica de Catalunya, Barcelona, Spain P. Baudrenghien, F.J. Galindo Guarch CERN, Geneva, Switzerland
	Transient beam loading compensation schemes, such as One-Turn-FeedBack (OTFB), require beam synchronous processing (BSP). Swept clocks derived from the RF, and therefore harmonic to the revolution frequency, are widely used in CERN synchrotrons; this simplifies implementation with energy ramping, where the revolution frequency changes. It is however not optimal for state-of-the-art digital hardware that prefers fixed frequency clocks. An alternative to the swept clocking is the use of a deterministic protocol, for example, White Rabbit (WR): a fixed reference clock can be extracted from its data stream, while enabling digital distribution of the RF frequency among other data. New algorithms must be developed for BSP using this fixed clock and the digital data transmitted on the WR link. This is the strategy adopted for the SPS Low Level RF (LLRF) upgrade. The paper gives an overview of the technical, technological and historical motivations for such a paradigm evolution. It lists the problems of fixed clock BSP, and presents an innovative solution based on a real-time variable ratio re-sampler for implementing an OTFB with the new fixed clock scheme.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML121
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Paper

Title

Page

THPML121

Compensation of Transient Beam Loading in Ramping Synchrotrons Using a Fixed Frequency Processing Clock

4957

SUSPL061

use link to see paper's listing under its alternate paper code

F.J. Galindo Guarch, J.M.M.A. Moreno Arostegui
Universitat Politécnica de Catalunya, Barcelona, Spain
P. Baudrenghien, F.J. Galindo Guarch
CERN, Geneva, Switzerland

Transient beam loading compensation schemes, such as One-Turn-FeedBack (OTFB), require beam synchronous processing (BSP). Swept clocks derived from the RF, and therefore harmonic to the revolution frequency, are widely used in CERN synchrotrons; this simplifies implementation with energy ramping, where the revolution frequency changes. It is however not optimal for state-of-the-art digital hardware that prefers fixed frequency clocks. An alternative to the swept clocking is the use of a deterministic protocol, for example, White Rabbit (WR): a fixed reference clock can be extracted from its data stream, while enabling digital distribution of the RF frequency among other data. New algorithms must be developed for BSP using this fixed clock and the digital data transmitted on the WR link. This is the strategy adopted for the SPS Low Level RF (LLRF) upgrade. The paper gives an overview of the technical, technological and historical motivations for such a paradigm evolution. It lists the problems of fixed clock BSP, and presents an innovative solution based on a real-time variable ratio re-sampler for implementing an OTFB with the new fixed clock scheme.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML121

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)