Characterising the Signal Processing System for Beam Position Monitors at the Front End Test Stand

Gary Boorman, Stephen Gibson, J Gale, N. Rajaeifar, Simon Jolly, Scott Lawrie, Alan Letchford

Research output: Chapter in Book/Report/Conference proceedingConference contribution


A number of beam position monitors (BPM) are being installed at the Front End Test Stand (FETS) H– ion source at the Rutherford Appleton Laboratory, UK, as part of the 3 MeV medium energy beam transport. The FETS ion source delivers pulses up to 2 ms long at a rate up to 50 Hz and a maximum current of 60 mA, with a 324 MHz micro-bunch structure imposed by the frequency of the FETS RF acceleration cavity. The response of an in- house designed button BPM has been simulated and then characterised on a wire-based test-rig and the results are presented. The output from a custom algorithm running on a commercial PXI-based FPGA signal processing system is evaluated using test signals from both a function generator and the BPM in the test-rig, to verify the speed and precision of the processing algorithm. The processing system can determine the beam position in eight BPMs, with a precision of better than 20 μm, within one microsecond of the signal sampling being completed.
Original languageEnglish
Title of host publication4th International Beam Instrumentation Conference
Subtitle of host publicationIBIC2015, Melbourne, Australia
Place of PublicationGeneva
PublisherJACoW Publishing
ChapterBPMs and Beam Stability
Number of pages4
ISBN (Electronic)978-3-95450-176-2
Publication statusPublished - Jan 2016

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