Proc. SPIE. 10034, 11th Conference on Integrated Optics: Sensors, Sensing Structures, and Methods
KEYWORDS: Superconductors, Computing systems, Control systems, Data acquisition, Data processing, Software development, Microelectronics, Particle accelerators, Analog electronics, Free electron lasers
Department of Microelectronics and Computer Science of Lodz University of Technology has long traditions and high expertise in field of design of electronic systems of various kinds and for several applications. DMCS has expertise in design of PCB (Printed Circuit Board) based and ASIC (Application Specific Integrated Circuit) based analog, mixed-signal and digital system designs. DMCS design teams participated in numerous national and international scientific research programs and grants. A series of commercial contracts was also conducted in DMCS. Many of these works finished with introduction of new systems into scientific installations or putting new product into general markets. Several DMCS achievements have been successfully patented. Such extensive experience in connection with wide field of scientific activities, enabled application of DMCS capabilities to quite different and even unusual electronic system applications aimed at work in extreme environments.
LLRF control system consists of a few basic subsystems with the basic aim to give good quality beam from the XFEL laser. Some of the se subsystems, which are described here are: transient detector, finite state machine, precise timing distribution network, EM field stabilization control loop, etc. The paper summarizes the latest developments of these systems done during the last year.
Bremsstrahlung gamma radiation and neutrons are produced during the operation of high-energy linear accelerators. A single circular tunnel is built for the X-ray Free Electron Laser (X-FEL), therefore most of electronic devices used to control the machine are going to be placed in the same vault as the main beam pipe. Therefore, the devices will be subjected to neutron and gamma radiation influence. Knowledge of neutron and gamma doses are crucial to understand and interpret radiation effects on electronic devices and systems dedicated to the operation in the environment of high-energy linear accelerators. Indeed, it is advisable to monitor radiation produced in the tunnel of X-FEL in real time to estimate the danger and the life-time of electronic components and devices. The realtime monitoring system dedicated to measure radiation produced in a linear accelerator tunnel was designed. The system utilizes two different types of detectors to gauge neutron fluence and gamma radiation dose during the operation of the accelerator driving X-FEL. Research described in this paper is focused on real time gamma radiation dosimetry. Silicon-based gamma-sensitive dosimeter RadFET was employed to quantify radiation produced during an operation of a linear accelerator. In order to fully investigate the feasibility of RadFET detector for gamma dosimetry various experiments and gamma radiation exposure tests were carried out using a cesium source and inside FLASH (Free Electron Laser At Hamburg) facility placed in a high-energy Research Centre DESY.
Proc. SPIE. 6159, Photonics Applications in Astronomy, Communications, Industry, and High-Energy Physics Experiments IV
KEYWORDS: Digital signal processing, Field programmable gate arrays, Control systems, Electronic components, Signal processing, Gamma radiation, Electronic filtering, Radiation effects, Error control coding, Control systems design
Radiation produced during the operation of high energy linear accelerators can pose a real danger to electronic devices. The electronics of X-Ray Free Electron Laser (X-FEL) accelerator will be placed in the main tunnel, therefore the system will be subjected to gamma bremsstrahlung radiation and neutrons.
Digital Signal Processors (DSPs) and high-density Field Programmable Gate Array (FPGA) devices are used to design the control system of the X-FEL accelerator. Influence of gamma on electronic systems can be decreased by implementation of suitable shielding. Despite the plurality of available methods protecting digital devices against neutrons influence, designing complex systems dedicated to operate in radiation environments is still a challenge. The mechanisms improving immunity of the digital systems can be achieved as an implementation of hardware redundancy or software algorithms modifications. In both cases additional resources are necessary. This paper highlights a DSP-based development environment, based on Texas Instruments TMS320C67 13 digital signal processor, dedicated to test software in radioactive environment. The master-board of the system is connected to the slave controller through EIA 485 differential interface, which assures reliable transmission for a long distance even in EMI polluted area. The developed programs can be downloaded through the interface and stored in a Flash memory.
Methods allowing improving the immunity to neutrons generated events, particularly Single Event Upsets (SEUs), were developed using triple redundancy, Hamming codes and doubled multipliers. Different experiments were carried out in Linac II accelerator to evaluate the designed programs and examine the whole system.
Proc. SPIE. 5948, Photonics Applications in Industry and Research IV
KEYWORDS: Digital signal processing, Optical amplifiers, Clocks, Interfaces, Power supplies, Field programmable gate arrays, Control systems, Telecommunications, Analog electronics, Free electron lasers
A new version of the SIMCON system is presented in this paper. The SIMCON stands for the microwave, resonant, superconductive accelerator cavity simulator and controller (embracing the hardware and software layers). The current version of the SIMCON is 3.1. which is a considerable step forward from the previous 8-channel version 3.0. which was released at the beginning of 2005 and was made operable in April. Many important upgrades were implemented in SIMCON 3.1. It is a stand-alone VME board (whereas SIMCON 3.0 was modular) based on the Virtex II Pro 30 chip with two embedded Power PCs and DSP blocks. It has Ethernet and multiple gigabit optical I/Os. The Simcon 3.1 board provides 10 ADC channels. The architecture idea and block diagrams of the PCB for SIMCON 3.1. are presented. Some of the applied novel technical solutions, Protel"R" views and schemes are shown. A number of initial conclusions were drawn from a few month experience with the development of this new board. The tables of predicted system parameters are quoted.
Strong fields of bremsstrahlung photons and photoneutrons are produced during the operation of high-energy electron linacs. Therefore, a mixed gamma and neutron radiation field dominates the accelerators environment. The gamma radiation induced Total Ionizing Dose (TID) effect manifests the long-term deterioration of the electronic devices operating in accelerator environment. On the other hand, the neutron radiation is responsible for Single Event Effects (SEE) and may cause a temporal loss of functionality of electronic systems. This phenomenon is known as Single Event Upset (SEU). The neutron dose (KERMA) was used to scale the neutron induced SEU in the SRAM chips. Hence, in order to estimate the neutron KERMA conversion factor for Silicon (Si), dedicated calibration experiments using an Americium-Beryllium (<sup>241</sup>Am/Be) neutron standard source was carried out. Single Event Upset (SEU) influences the short-term operation of SRAM compared to the gamma induced TID effect. We are at present investigating the feasibility of an SRAM based real-time beam-loss monitor for high-energy accelerators utilizing the SEU caused by fast neutrons. This paper highlights the effects of gamma and neutron radiations on Static Random Access Memory (SRAM), placed at selected locations near the Superconducting Linear Accelerator driving the Vacuum UV Free Electron Laser (VUVFEL) of DESY.