Beam position monitor (BPM) is an important part of beam instrument system

and the algorithm study is of significance to development of a digital BPM system. In this study

with the digital signal process board ICS-1554A-002 (GE Corp.)

raw data from the SSRF storage ring

and a signal generator

were sampled

and processed off line on Matlab. Sum-difference algorithm was applied to the turn-by-turn beam position processing. Based on the Software Radio Theory

three down frequency algorithm were designed

i.e. multilevel decimation

single level decimation and the special algorithm with FFT (Fast Fourier Transform). For each algorithm

the theories and results are discussed and compared. The algorithm best fits to the turn-by-turn signal processing and FPGA implementation is acquired.