An Iterative Learning Control Approach for Radio Frequency Pulse Compressor Amplitude and Phase Modulation

Abstract

Radio Frequency (RF) pulse compressors are used in linear accelerators (Linac) to achieve high power levels by shortening the RF pulse length. In their original form, the phase of the incoming pulse is reversed by 180 $^{\circ} $ which generates a high peak power at the output of the pulse compressor, followed by an exponential decay. This pulse shape however is not appropriate with regard to timing stability as well as for having equal energy gain for multi-bunch operation. To achieve flat-topped pulses, a method has been previously proposed that analytically modulates the input phase waveform. In the present contribution an alternative way to producing flat-topped RF pulses is proposed which is based on Iterative Learning Control techniques. This approach manipulates the input waveforms iteratively in order to generate flat-topped amplitude and phase pulses at the output of the pulse compressor.