Digital Low-Level RF System for the CERN Linac3 Accelerator

A major consolidation of the aging RF system of the CERN Linac3, the ion source for the whole CERN accelerator chain, started during the Long Shutdown II. The main changes were an upgrade of the analogue Low-Level RF system (LLRF) and replacement of the 350 kW tube amplifiers by a solid-state equivalent. The state-of-the-art digital LLRF system enabled new sophisticated features in field manipulations, significantly increased the operational flexibility and improved operational reliability and availability. The paper presents the new architecture, a low noise master clock generator, digital signal processing with direct sampling of the RF signals, pulse parameter measurement or cavity resonance control.