摘要
目的 介绍数据采集系统采集速率的一种简单实用的精确评价方法 ,即正弦波拟合评价法 .方法 核心技术除了采用最小二乘波形拟合手段外 ,还采用了一种性能独特的单频数字滤波器技术 ,该滤波器仅对噪声和谐波有滤除作用 ,从原理上说 ,对于正弦信号的幅度、相位、频率和直流分量 4个参数均无影响 .讨论了评价过程的误差来源 ,以及减小其评价误差的几种对策 ;并阐述了滤波方法及过程 ,同时 ,以滤波前后效果对比的方式给出了评价过程的计算机仿真结果 .结果 使用该方法评价采集速率 ,结果不确定度可达到 1 0 - 6量级 ,加上数字滤波器后 ,不确定度可降低一半以上 .
Aim\ The sine wave curve fit method is introduced which is a simple and useful evaluation method to evaluate the sampling rate of data acquisition systems. Methods\ Besides filtering the noise and harmonic distortion of the sine wave, there is not any effects on the four parameters of sine wave in filtering in principle. The error sources are described, and finally some methods to reduce the uncertainty of evaluation are discussed. The imitation and expriment results before and after filtering are given. Results\ By using the method in this paper, the uncertainty of sample rates evaluation results can be to 10\+\{-6\} magnitude level. After filtering, it can be to half or lower. Conclusion The method in this paer can be used to precisely evaluate sampling rates.
出处
《华北工学院测试技术学报》
2000年第3期148-153,共6页
Journal of Test and Measurement Technology
关键词
数据采集系统
采集速率
通道
评价
data acquisition
sampling
rates
measurement method
evaluation
error analysis
