扫描相机标定脉冲信号位置的确定及噪声处理  

Calibration pulse position determination and noise processing of streak camera

作　　者：舒桦[1] 傅思祖[1] 黄秀光[1] 马民勋[1] 顾援[1] 

机构地区：[1]中国工程物理研究院上海激光等离子体研究所,上海201800

出　　处：《强激光与粒子束》2007年第10期1667-1670,共4页High Power Laser and Particle Beams

基　　金：国家863计划项目资助课题

摘　　要：扫描相机标定数据处理中的一个关键问题是如何准确确定脉冲信号的位置,实验数据的信噪比和脉冲信号位置的定义方法都会对标定结果的准确性产生影响。采用了取半高宽的方法来确定扫描相机标定脉冲信号的位置,在信噪比比较高(大于100)的情况下,该方法确定标定信号的位置可以达到亚像素水平。对于信噪比比较低(小于10)的实验数据,先采用快速傅里叶变换方法对其进行滤波,通过滤波可以极大地抑制噪声信号的影响,然后采用"半高宽法"确定脉冲信号的位置,最后得出可信的标定结果。当扫描相机定在0.3 ns的扫描档时,通过该方法得到的扫描速度为0.214 ps/pixel,扫描不确定度为0.002 9 ps/pixel,拟合线性相关系数为0.999 7。A key problem in streak camera data processing is how to determine the position of the signal pulse, and the results will be effected by the signal to noise ratio（SNR） of the experimental data and the signal pulse position determination method. In the paper, FWHM（half maximum and half width） method is used to determine the single pulse position. The method could determine the signal pulse position with sub-pixel precision when the SNR more than 100 ： 1. As for the data with bad signal to noise ratio（SNR less than 10 ： 1）, a Fast Fourier Transform method is used to filter the noise first, then the pulse position is determined by the FWHM method. And the streak camera calibration data of the super-fast sweep rate was processed. The sweep speed is （0. 214±0. 002 9）ps/pixel. The linear dependent coefficient is 0. 999 7, which shows the streak camera scanning linearity is good.

关 键 词：扫描相机 标定 快速傅里叶变换 半高宽法 标准具 噪声 

分 类 号：TH714[机械工程—测试计量技术及仪器]