Estimation of the waveform of fine structure pulse with resonator

An electron beam of linac consists of fine structure pulse trains with the period of the acceleration frequency. To estimate the waveform of the fine structure pulse, it is necessary to obtain complex amplitude the electric field radiated from electron beam at every frequency. To determine the complex amplitude, we should measure not only the amplitudes but also the phases. Since The Fabry Perot Resonator is an open type resonator, its resonance characteristic of distance between mirrors depend on frequency. Choosing the distance, we can make some types of filter. When we use the non-1inea detector, detecting result of the synthesized two frequency components depend on the distance of phase between them. In this paper, we show the phase detecting system with Fabry Perot Resonator and non-linear detector. (author)