摘要
在UV(紫外光)通信系统中,噪声对信号会产生比较明显的干扰。为了提高系统的通信性能,文章对UV通信系统中的噪声进行了分析。设计了一个模块对噪声进行采样,并分析了PMT(光电倍增管)暗电流噪声、PCB(印制电路板)热噪声、EMI(电磁干扰)噪声以及电源引入的噪声等4种噪声的时域和频域特性,及其对系统性能的影响。为了克服模拟滤波性能不理想的缺点,在接收端采用FPGA(现场可编程门阵列)设计了一个数字滤波器来抑制噪声。实验结果表明,该数字滤波器对SNR(信噪比)有3~7dB的改善。
Noises in the Ultraviolet (UV) communication system bring about significant interference in signal transmission. In order to improve the system performance, this paper designs a module to sample the noises in the system, including Photomul-tiplier Tube (PMT), dark current noise, PCB hot noise, Electromagnetic Interference (EMI) noise and noises induced by pow-er source and analyze their characteristics in time and frequency domains and their effects on the system performance. To over-come the disadvantages of analog filters, it develops a digital filter at the receiver end by using FPGA to suppress the noise. The experimental results show that this digital filter imoroves the Signal to Noise Ratio (SNR) bv 3-7 dB.
出处
《光通信研究》
北大核心
2013年第2期65-69,共5页
Study on Optical Communications
基金
国家"八六三"计划资助项目(2008AA12Z225)
教育部青年科研创新计划资助项目(2012RC0405)