Libera Cavity BPM

Libera Cavity BPM is a beam position monitor readout system designed to be used in linear machines with cavity-type beam position monitor pickups. Libera Cavity BPM is particularly indicated for FEL undulator sections and interaction points where accurate position measurements are required. The system processes the signals form low-Q and high-Q S-band and C-band cavities providing the user a very precise beam position measurements resolved at single bunch level.

Product Description


  • sub-micrometer measurement capabilities
  • directly processing S-band and C-band cavity signals
  • extended dynamic range by means of calibrated variable attenuation
  • single bunch measurements capabilities with low quality factor cavities support down to 16 ns bunch spacing
  • calibrated position readout

Data processing:

Libera CavityBPM acquires the cavity signals by means of frequency conversion and intermediate frequency sampling. Calibrated variable attenuators further increase the instrument dynamic range capabilities. The signals are then processed at FPGA level.

A special deconvolution filtering scheme can be then used to separate partially overlapped bunches. Then a time-domain position calculation algorithm is used to determine the beam position for every single bunch.



Typical position readout standard deviation is < 1µm RMS, at 1mm full scale, for 32 dB dynamic range. (However, it depends also on other factors like: the cavity sensitivity, available signal strength and position measurement range.)

Libera Cavity BPM
Clear filters
Kees Scheidt
Diagnostics Head (ESRF, Grenoble)

On our Booster beam, we collected much data and features, that we could not measure or even detect before.

Engineering Executive
NDA locked

The prototyping and development Instrumentation Technologies has provided for our team has been exceptional.