MTCA.4 LLRF system for the European XFEL

Due to its scale and tight specifications, the European XFEL poses real challenges in the field of low-level radio-frequency (LLRF) control. The implementation of this semi-distributed control system on the microTCA for physics (MTCA.4) platform triggered numerous designs of electronic boards and helped refine the usage of MTCA.4 technology for physics and control systems. This paper presents an overview of the MTCA.4-based LLRF system for the European XFEL with an emphasis on the system architecture decisions. The multiple functionalities of this highly modular design will be explained as well as the opportunities of the MTCA.4 technology for other applications.