Large-scale real-time signal processing in physics experiments: The ALICE TPC FPGA pipeline
Abstract
For LHC Run 3, the ALICE Time Projection Chamber was upgraded to operate in continuous readout mode. Interaction rates of up to 50 kHz in Pb-Pb collisions require real-time processing of more than 3 TB/s of raw detector data. This requirement is met by a custom FPGA-based processing pipeline that performs the complete front-end data treatment fully in-stream, including common-mode correction, pedestal subtraction, ion-tail filtering, zero suppression, and dense data packing. A central element of the design is a highly parallel common-mode correction algorithm operating directly on the streaming data. It robustly identifies signal-free readout channels on a time-bin basis and applies pad-dependent scaling to compensate for local variations in capacitive coupling in the GEM readout. In combination with pedestal subtraction and ion-tail filtering, this enables accurate baseline restoration under extreme high-occupancy conditions, preventing signal loss while efficiently suppressing noise prior to zero suppression. The pipeline operates continuously at the full detector bandwidth and reduces the raw input rate to about 900 GB/s for Pb-Pb collisions at the target interaction rate. Overall, it represents a large-scale FPGA-based real-time signal-processing implementation for high-energy physics detector readout.
Keywords
Cite
@article{arxiv.2601.15868,
title = {Large-scale real-time signal processing in physics experiments: The ALICE TPC FPGA pipeline},
author = {J. Alme and T. Alt and C. Andrei and V. Anguelov and H. Appelshäuser and M. Arslandok and R. Averbeck and M. Ball and G. G. Barnaföldi and P. Becht and R. Bellwied and A. Berdnikova and B. Blidaru and L. Boldizsár and L. Bratrud and P. Braun-Munzinger and M. Bregant and C. L. Britton and H. Büsching and H. Caines and P. Chatzidaki and P. Christiansen and T. M. Cormier and L. Döpper and R. Ehlers and L. Fabbietti and F. Flor and J. J. Gaardhøje and M. G. Munhoz and C. Garabatos and P. Gasik and Á. Gera and P. Glässel and N. Grünwald and T. Gündem and T. Gunji and H. Hamagaki and J. W. Harris and P. Hauer and E. Hellbär and H. Helstrup and A. Herghelegiu and H. D. Hernandez Herrera and Y. Hou and C. Hughes and M. Ivanov and J. Jäger and Y. Ji and J. Jung and M. Jung and B. Ketzer and S. Kirsch and M. Kleiner and A. G. Knospe and M. Korwieser and M. Kowalski and L. Lautner and M. Lesch and C. Lippmann and G. Mantzaridis and R. D. Majka and A. Marin and C. Markert and S. Masciocchi and A. Matyja and M. Meres and D. L. Mihaylov and D. Miśkowiec and R. H. Munzer and H. Murakami and K. Münning and A. Nassirpour and C. Nattrass and B. S. Nielsen and W. A. V. Noije and A. C. Oliveira Da Silva and A. Oskarsson and K. Oyama and L. Österman and Y. Pachmayer and G. Paić and M. Petris and M. Petrovici and M. Planinic and J. Rasson and K. F. Read and A. Rehman and R. Renfordt and A. Riedel and K. Røed and D. Röhrich and E. Rubio and A. Rusu and S. Sadhu and B. C. S. Sanches and J. Schambach and A. Schmah and C. Schmidt and A. Schmier and K. Schweda and D. Sekihata and D. Silvermyr and B. Sitar and N. Smirnov and H. K. Soltveit and C. Sonnabend and S. P. Sorensen and J. Stachel and L. Šerkšnytė and G. Tambave and K. Ullaland and B. Ulukutlu and D. Varga and O. Vazquez Rueda and B. Voss and J. Wiechula and B. Windelband and J. Wilkinson and J. Witte and A. Yadav and F. Zanone and S. Zhu},
journal= {arXiv preprint arXiv:2601.15868},
year = {2026}
}