A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z  

Geng, Z.

Paper Title Page
WEPMN028 Development of Digital Low-level RF Control System using Multi-intermediate Frequencies 2110
 
  • T. Matsumoto, S. Fukuda, H. Katagiri, S. Michizono, Y. Yano
    KEK, Ibaraki
  • Z. Geng
    IHEP Beijing, Beijing
 
  Digital low level rf (LLRF) control system has been developed in Superconducting RF Test Facility (STF) at KEK to carry out the accelerating electric field stability of 0.3% (rms) in amplitude and 0.3 degree (rms) in phase, respectively. In the digital LLRF system, rf probe signal from cavity is down-converted to intermediate frequency (IF) for acquisition at analog-to-digital converter (ADC) and the number of ADCs required is equal to the number of cavities. In order to decrease the number of ADCs, a new digital LLRF control system is under development. In this LLRF system, rf signals are down-converted to different IF and combined. The combined signal is detected with one ADC and I/Q components of each rf signal are calculated with digital signal processing. This paper describes a result of simulation and estimation using cavity simulator based on FPGA board about this new technique.  
WEPMN029 Status of the Low-Level RF System at KEK-STF 2113
 
  • S. Michizono, S. Fukuda, H. Katagiri, T. Matsumoto, T. Miura, Y. Yano
    KEK, Ibaraki
  • Z. Geng
    IHEP Beijing, Beijing
 
  RF field stabilities of less than 0.3%, 0.3deg. are required at STF llrf system. In order to satisfy these requirements, digital FB system using a FPGA is adopted. The FB system consists of a FPGA (VirtexIIPro30) with ten 16-bit ADCs and two 14-bit DACs. The rf (1.3 GHz) probe signals are downconverted to the IF (10 MHz) and directly acquired at ADCs. Total 8 cavities will be installed at STF-Phase 1 in 2007 and vector sum control of 8 cavity signals will be carried out. The performance of the FB system is examined with electric cavity simulators prior to the rf operation.