数字正弦信号失真度测量仪的设计  

Design of sinusoidal signal distortion measurement instrument for digital control

作　　者：丁跃浇[1] 陈松[1] 荣军[1] 谭荣[1] 

机构地区：[1]湖南理工学院信息与通信工程学院,湖南岳阳414006

出　　处：《微型机与应用》2015年第12期64-66,69,共4页Microcomputer & Its Applications

基　　金：国家级"电子信息工程"专业综合改革试点专业(高教司函[2013]5号)

摘　　要：针对模拟控制正弦信号失真度测试仪体积大、测试精度低和使用不方便的缺点,设计了数字控制正弦信号失真度测试仪。该系统以单片机和FPGA相结合为控制核心,运用快速傅里叶变换(FFT)为主要分析工具,对信号输入电路进行程控衰减、放大与预滤波处理,实现了量程自动转换和数据采样,并且成功避免了频率混叠现象。最后,系统完成了软硬件电路设计后,经过测试,该系统能够对输入信号进行总功率和谱功率的测量和分析,并能正确地判断未知信号的周期性并测量出周期信号的周期,也能正确测量规定频率范围内正弦信号的失真度,在高校实验室有广泛的应用价值。For the large volume, low testing precision and inconvenient use of sinusoidal signal distortion measurement instrument for analog control, the paper designs digital control distortion measurement instrument. The system uses single-chip microcomputer and FPGA as the control core, and uses FF＇I＂ as the main analytical tool. The system makes the signals of input circuit programmable attenuation, amplification and pre-filtering process, and also realizes the automatic range switching and data sampling, and successfully avoids the phenomenon of frequency aliasing. At last the system completes the design of software and hardware circuit. After testing, the system can make the measurement and analysis of total power and spectral power, correctly judge the period of unknown signal periodicity, and correctly measure the distortion of sinusoidal signal with specified frequency. It has a wide range of value of application in the university laboratory.

关 键 词：失真度 数字控制 频谱 频率混叠 

分 类 号：TM46[电气工程—电器]