原子能科学技术2026，Vol.60Issue(3)：724-732,9.DOI:10.7538/yzk.2025.youxian.0443
基于锁相采样的合肥光源逐束团束长测量系统研制
Development of Bunch-by-bunch Bunch Length Measurement System for Hefei Light Source Based on Phase-locked Sampling
摘要
Abstract
To investigate input transients and longitudinal beam instabilities in high-energy electron accelerator storage rings,the beam diagnostics team at the Shanghai Synchrotron Radiation Facility(SSRF)developed a bunch-by-bunch bunch length measurement system based on oscilloscope random sampling.This system utilizes a high-speed oscilloscope to capture raw beam position monitor(BPM)signals,which are subsequently processed by data analysis scripts for bunch length calculations.However,the computational efficiency and real-time performance of this system were limited.The process is cumbersome and computationally inefficient.In the case of multiple bunches,calculating a set of data can take up to two hours,which greatly inconveniences real-time monitoring of the machine status.To optimize computational efficiency and real-time performance,a bunch-by-bunch bunch length measurement system was developed based on phase-locked sampling with a processor.This system directly acquires raw beam signals through the processor and performs bunch length calculations in real time.It can significantly streamline the data processing flow and reduce computation time.Nevertheless,the processor's analog-to-digital converter(ADC)acquisition board faced the challenge of low sampling rates.Given that the processor is equipped with eight sampling channels,a one-to-eight equal-power-division delay signal conditioning front-end which equally spaced delays to the eight-way power-divided signals was designed.This method increased the system sampling rate eightfold through interleaved sampling.Additionally,by calibrating the consistency of each channel in the measurement system and the system's transmission impedance,the system is able to accurately reconstruct the original BPM signal waveforms.For Gaussian-distributed beams,the system achieves a bunch-by-bunch,tum-by-tum bunch length measurement accuracy of 0.17 ps,with a dynamic range spanning thousands of turns.Furthermore,this measurement system has been successfully deployed at the Hefei Light Source(HLS)and used to observe beam instabilities in the storage ring.This system can improve the computational efficiency of bunch length measurements and enable real-time observation of bunch length variations in the storage ring.It holds potential for future deployment in other storage rings.关键词
逐束团诊断/锁相采样/束长测量/纵向不稳定性Key words
bunch-by-bunch diagnostics/phase-locked sampling/bunch length measurement/longitud-inal instability分类
能源科技引用本文复制引用
汪宏双,冷用斌..基于锁相采样的合肥光源逐束团束长测量系统研制[J].原子能科学技术,2026,60(3):724-732,9.基金项目
中国科学院大科学装置维修改造项目 （）
