Prototype Digital Beam Position And Phase Monitor For The 100mev Proton Linac Of Pefp

The PEFP (Proton Engineering Frontier Project) at the KAERI (Korea Atomic Energy Research Institute) is building a high-power proton linear accelerator aiming to generate 100-MeV proton beams with 20-mA peak current (pulse width and max. repetition rate of 1 ms and 120 Hz respectively). We are developing a prototype digital BPPM (Beam Position and Phase Monitor) for the PEFP linac utilizing the digital technology with field programmable gate array (FPGA). The RF input signals are down converted to 10 MHz and sampled at 40 MHz with 14-bit ADC to produce 1 and Q data streams. The system is designed to provide a position and phase resolution of 0.1% and 0.1-RMS respectively. The fast digital processing is networked to the EPICS-based control system with an embedded processor (Blackfin).