同步辐射光与束流信号具有相同的时间结构,测量同步辐射光并基于频域的信号处理方法可得到束团的长度。基于该原理,研制了采用谐波法测量束团长度的系统。该系统用高速光电接收器将同步光转换为电信号,然后采集该信号的四路频率分量,计算得到束团长度。阐述了该系统的软硬件设计,并应用该系统测量了束团长度随流强的变化规律,与条纹相机的测量结果相吻合。
The time structure of the synchrotron light is same as beam signal in the storage ring.Therefore,the bunch length measurement can be done by measuring the optical pulse in frequency-domain.Based on the principle,the bunch length measurement system was developed using harmonic method.The system used the high-speed photoreceiver that converted optical signal to electrical signal,collected four of the signal frequency components,and then calculated the bunch length.The hardware and software design of the system was presented.The variation of bunch length with beam current was measured using the system,which was consistent with the measurement result of the streak camera.