Implementation of Digital Beam Position Monitor Signal Processing Algorithm in FPGA Based on BEPC Ⅱ

The digital beam position monitor (BPM) algorithm is the core part of the digital BPM system, which plays a decisive role in the accuracy of beam position measurement. Based on the simulation of the digital BPM algorithm with MATLAB, the optimized FPGA algorithm was implemented on the self-made electronic hardware. First, the overall design and implementation scheme of digital BPM algorithm was introduced. Secondly, the design principle of each function module of digital BPM algorithm and its implementation method in FPGA were introduced in detail. Finally, laboratory tests were carried out with the conditions of input signal frequency of 499.8 MHz, intensity of -10 dBm and BPM probe sensitivity coefficient of 23. Test results show that the turn by turn position resolution is 2.96 μm, fast response position resolution is 0.65 μm, and closed orbit position resolution is 0.33 μm. The test results demonstrate that the optimized algorithm has a good performance on the beam position measurement.