Nuclear Science and Techniques

《核技术》(英文版) ISSN 1001-8042 CN 31-1559/TL     2019 Impact factor 1.556

Nuclear Science and Techniques ›› 2013, Vol. 24 ›› Issue (2): 020101 doi: 10.13538/j.1001-8042/nst.2013.02.007


Design and measurement of signal processing system for cavity beam position monitor

WANG Baopeng1,2  LENG Yongbin1,*  YU Luyang1  ZHOU Weimin1  YUAN Renxian1  CHEN Zhichu1   

  1. 1Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jiading campus, Shanghai 201800, China
    2University of the Chinese Academy of Sciences, Beijing 100049, China
  • Received:2012-09-20
  • Contact: LENG Yongbin
  • Supported by:

    Supported by National Natural Science Foundation of China (No.11075198)

WANG Baopeng, LENG Yongbin, YU Luyang, ZHOU Weimin, YUAN Renxian, CHEN Zhichu. Design and measurement of signal processing system for cavity beam position monitor.Nuclear Science and Techniques, 2013, 24(2): 020101     doi: 10.13538/j.1001-8042/nst.2013.02.007


In this paper, in order to achieve the output signal processing of cavity beam position monitor (CBPM), we develop a digital intermediate frequency receiver architecture based signal processing system, which consists of radio frequency (RF) front end and high speed data acquisition board. The beam position resolution in the CBPM signal processing system is superior to 1 μm. Two signal processing algorithms, fast Fourier transform (FFT) and digital down converter (DDC), are evaluated offline using MATLAB platform, and both can be used to achieve, the CW input signal, position resolutions of 0.31 μm and 0.10 μm at –16 dBm. The DDC algorithm for its good compatibility is downloaded into the FPGA to realize online measurement, reaching the position resolution of 0.49 μm due to truncation error. The whole system works well and the performance meets design target.

Key words: Cavity beam position monitor, RF front end, Digital down converter, Fast Fourier transform, FPGA