非减性Dither与过采样技术在低频模拟采集系统中的应用  

Application of Non-decreasing Dither and Oversampling Technology in Low Frequency Analog Acquisition System

作　　者：逯宏超 赵冬青 储成群 焦新泉 LU Hongchao;ZHAO Dongqing;CHU Chengqun;JIAO Xinquan(School of Instrument and Electronisc,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学仪器与电子学院,太原030051

出　　处：《实验室研究与探索》2019年第2期95-98,共4页Research and Exploration In Laboratory

基　　金：国家自然科学基金青年科学基金项目(61704160)

摘　　要：Dither技术是提高多通道模拟采集系统动态性能的有效方法。通过分析Dither技术改善采集系统无杂散动态范围(SFDR)的原理,搭建了多通道模拟采集系统测试平台,通过FPGA控制A/DC对输入的满量程正弦信号采样,利用过采样和均值滤波技术来提高采集精度。实验结果表明:采集系统的动态性能明显改善,SFDR从71 dB提高到78 dB,SNR下降了1.2 dB。The Dither method is an effective way to improve the dynamic performance of multi-channel analog acquisition system.By analyzing the principle that Dither technology improves the non spur-free dynamic rage(SFDR)of the acquisition system,a test platform for multi-channel analog acquisition system is built.FPGA controls ADC to collect sinusoidal signals of full scale input,and improves the acquisition accuracy by oversampling and mean filtering.The experimental results show that the dynamic performance of the acquisition system is obviously improved,SFDR increases from 71 dB to 78 dB,and SNR decreases by 1.2 dB.

关 键 词：Dither方法 过采样 均值滤波 杂散动态范围 信噪比 

分 类 号：TN702[电子电信—电路与系统]