The Application of Direct RF Sampling System on Cavity BPM Signal Processing

Cavity BPM signal processing system normally consists of two modules, first one is RF conditioning module(RF front end) to down convert the BPM signal to IF, second one is IF signal digitizer and digital signal processing module (DAQ) to calculate beam position and communicate with control system. The RF front end complicates the system and introduces noise. A direct RF sampling system has been constructed to process the cavity BPM signal, which structure is more concise and performance is better compared to the conventional system. The evaluation tests and an on-line RF DAQ system will be introduced in this paper.