摘要
分析工业CT探测系统的噪声特性,并且对该探测系统噪声的来源、影响因素等进行详细研究。首先,对噪声处理的一般方法进行介绍。然后,针对低能的工业CT系统,设计了一组实验,测试其信号功率与噪声功率。最后,对测得的数据进行处理与统计,计算信号与噪声的大小,总结噪声的统计规律。实验结果证明:本底噪声的大小基本不会变化;噪声与积分时间、放大倍数有关;DDC118环节引入的噪声很小。探测系统噪声主要由前端模拟电路以及射线源部分引入,其成分主要有低频噪声与白噪声,因此可以通过降低系统带宽的方法削弱噪声、提高信噪比。
After analyzing the noise characteristics of industrial CT detecting system, this paper researches particularly the sources and influencing factors of the detecting system noise. Firstly, the general method of data processing was introduced. Secondly, a series of experiments based on low-energy industrial CT system were designed to test the signal power and noise power. Finally, experimental data were processed by statistical method, including computation of signal level, noise level and rule of noise. The experimental results show that：background is stable, noise level is related to integration time and amplification, noise introduced by DDC118 is low. The noise of detecting system is mainly caused by analog circuit and ray-source, which is composed of low frequency.noise and white noise. Therefore, signal-to-noise ratio （SNR） can be improved by reducing system bandwidth.
出处
《核电子学与探测技术》
CAS
CSCD
北大核心
2010年第7期929-934,共6页
Nuclear Electronics & Detection Technology
基金
重庆市科技攻关项目(CSTC2009AC3047)
