数字束流位置探测器系统的信噪比需求分析

Signal-to-noise ratio requirement analysis for digital beam position monitor system

摘要: 以高能同步辐射光源（HEPS）对BPM提出的位置测量分辨率要求为出发点，介绍了BPM系统的整体架构并推导出BPM系统的信号链路中各级信号所需达到的信噪比；并根据ADC采样数据的信噪比需求，计算出ADC采样时钟的抖动需求；最后介绍了能够测量BPM信号信噪比和采样时钟抖动的BPM测试平台。各项结论可以作为判断BPM系统各部分能否达到HEPS工程要求的标准。

Abstract: The signal-to-noise ratio (SNR) of DBPM signal is one of the important parameters to measure the performance of BPM, and it plays a decisive role in the resolution of beam position measurement. Based on the position measurement resolution requirements of high energy photon source (HEPS) for BPM, this paper firstly introduces the overall architecture of BPM system and deduces the signal-to-noise ratio of signals at all levels in the signal link of BPM system. Then the calculation method of ADC sampling clock jitter and BPM electronics test platform are introduced. The conclusions in this paper can be used as a standard to judge whether each part of BPM system can meet the requirements of HEPS, which is of great significance to promote the batch application of self-developed BPM electronics in HEPS engineering.