Software Layer for SIMCON ver. 1.1., FPGA based TESLA Cavity Control System; USER'S MANUAL

The paper describes design and practical realization of low and high level software for laboratory purposes to control FPGA-based LLRF electronic equipment for TESLA. There is presented a universal solution for particular functional devices of the control system with FPGA chips. The paper describes architecture of software layers and programming solutions of hardware communication based on the proprietary Internal Interface (II) technology. Such a solution was used for the Superconducting Cavity Controller and Simulator (SIMCON) for TESLA experiment (Test Facility) in DESY. The examples of the build and tested software blocks were given in this paper. This documentation is a unity with TESLA Reports published in 2004 by the Elhep and describing the SIMCON hardware, ver.1.0. The paper was written in a form of a User’s Manual

TESLA Report 2004-10 Software layer for FPGA-based TESLA cavity control system (part I)

The paper describes design and practical realization of software for laboratory purposes to control FPGA-based photonic and electronic equipment. There is presented a universal solution for all relevant devices with FPGA chips and gigabit optical links. The paper describes architecture of the software layers and program solutions of hardware communication based on Internal Interface (II) technology. Such a solution was used for superconducting Cavity Controller and Simulator (SIMCON) for the TESLA experiment in DESY (Hamburg). A number of practical examples of the software solutions for the SIMCON system were given in this paper

DOOCS environmentfor FPGA-based cavity control systemand control algorithms development

The paper describes the concept and realization of the DOOCS control software for FPGAbasedTESLA cavity controller and simulator (SIMCON). It bases on universal softwarecomponents, created for laboratory purposes and used in MATLAB based controlenvironment. These modules have been recently adapted to the DOOCS environment toensure a unified software to hardware communication model. The presented solution can bealso used as a general platform for control algorithms development. The proposed interfacesbetween MATLAB and DOOCS modules allow to check the developed algorithm in theoperation environment before implementation in the FPGA. As the examples two systemshave been presented

Experimental Evaluation of Sub-Sampling IQ Detection for Low-Level RF Control in Particle Accelerator Systems

The low-level radio frequency (LLRF) control system is one of the fundamental parts of a particle accelerator, ensuring the stability of the electro-magnetic (EM) field inside the resonant cavities. It leverages on the precise measurement of the field by in-phase/quadrature (IQ) detection of an RF probe signal from the cavities, usually performed using analogue downconversion. This approach requires a local oscillator (LO) and is subject to hardware non-idealities like mixer nonlinearity and long-term temperature drifts. In this work, we experimentally evaluate IQ detection by direct sampling for the LLRF system of the Polish free electron laser (PolFEL) now under development at the National Centre for Nuclear Research (NCBJ) in Poland. We study the impact of the sampling scheme and of the clock phase noise for a 1.3-GHz input sub-sampled by a 400-MSa/s analogue-to-digital converter (ADC), estimating amplitude and phase stability below 0.01% and nearly 0.01°, respectively. The results are in line with state-of-the-art implementations, and demonstrate the feasibility of direct sampling for GHz-range LLRF systems

The European XFEL LLRF System

The European X-Ray free electron laser accelerator consists of 808 superconducting cavities grouped in 25 RF stations. The challenges associated with the size and complexity of this accelerator require a high-precision, modular and scalable low level RF (LLRF) system. The Micro TCA technology (MTCA.4) was chosen to support this system and adapted for RF standards. State-of-the-art hardware development in close collaboration with the industry allowed for the system continuity and maintainability. The complete LLRF system design is now in its final phase and the designed hardware was installed and commissioned at FLASH. The MTCA.4 LLRF architecture and system performance results will be shown. Operation strategies and future automation algorithms for performance optimization will also be presented in this paper. Copyright © 2012 by IEEE.status: publishe

Recent developments of the European XFEL LLRF system

The European X-ray free electron laser (XFEL) [1] comprised more than 800 TESLA-type super-conducting accelerator cavities which are driven by 25 high-power multibeam klystrons. For reliable, reproducible and maintainable operation of the linear accelerator (linac), the low-level radio frequency (LLRF) system will process more than 3000 RF channels. Furthermore, stable FEL operation demands field stability better than 0.01 deg. in phase and 0.01 % in amplitude. To cope with these challenges, the LLRF system is developed on a MTCA.4 [2] platform. In this paper, we give an update on the latest electronics developments, improvements of the feedback controller algorithm and measurement results at FLASH. Copyright © 2013 by JACoW- cc Creative Commons Attribution 3.0 (CC-BY-3.0).status: publishe