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TY - CONF AU - Grech, L. AU - Alves, D. AU - Gąsior, M. AU - Jackson, S. AU - Jones, O.R. AU - Levens, T.E. AU - Valentino, G. AU - Wenninger, J. ED - Tavares, Daniel ED - Picoreti, Renan ED - Bruno, Gustavo ED - Marques, Sergio ED - Schaa, Volker R.W. TI - An Alternative Processing Algorithm for the Tune Measurement System in the LHC J2 - Proc. of IBIC2020, Santos, Brazil, 14-18 September 2020 CY - Santos, Brazil T2 - International Beam Instrumentation Conference T3 - 9 LA - english AB - The betatron tune in the Large Hadron Collider (LHC) is measured using a Base-Band-Tune (BBQ) system. Processing of these BBQ signals is often perturbed by 50Hz noise harmonics present in the beam. This causes the tune measurement algorithm, currently based on peak detection, to provide incorrect tune estimates during the acceleration cycle with values that clearly oscillate between neighbouring harmonics. The LHC tune feedback cannot be used to its full extent in these conditions as it relies on stable and reliable tune estimates. In this work we present two alternative tune measurement algorithms, designed to mitigate this problem by ignoring small frequency bands around the 50Hz harmonics and estimating the tune from spectra with gaps. One is based on Gaussian Processes and the other is based on a weighted moving average. We compare the tune estimates of the new and present algorithms and put forward a proposal that can be implemented during the renovation of the BBQ system for the next physics run of the LHC. PB - JACoW Publishing CP - Geneva, Switzerland SP - 162 EP - 165 KW - simulation KW - controls KW - betatron KW - damping KW - feedback DA - 2020/10 PY - 2020 SN - 2673-5350 SN - 978-3-95450-222-6 DO - doi:10.18429/JACoW-IBIC2020-WEPP27 UR - https://www.jacow.org/ibic2020/papers/wepp27.pdf ER -