周期信号软件同步采样方法的研究（基于Matlab）

测控论文编号:CK075   论文字数:11627,页数:27

 目录

 摘要 I
1  前言 1
2  三种采样方法 2
2.1  双速率同步采样法 2
2.2  偏差累积增量法 3
2.2.1 上述非均匀同步采样序列的DFT 4
2.2.2 一个较理想的非均匀同步采样法 5
2.3  参数自寻优等间隔同步采样法 6
3  三种采样方法各自的优缺点 10
3.1  双速率采样法的优缺点 10
3.2  偏差累积增量法的优缺点 10
3.3  参数自寻优采样法的优缺点 10
4  软件同步采样的误差分析和频域特性分析 11
4.1  同步采样的误差分析 11
4.2  非整周期采样谐波分析的算法 11
4.3  软件同步采样方法的频域特性分析 12
4.3.1 标准正弦信号的频谱 12
4.3.2 正弦信号中存在谐波干扰时的频谱分析 13
4.3.3 不同同步误差对基波谱线的影响 14
5  新方法探索 15
6 软件同步采样测量法误差研究现况及应用中的问题 20
7 总结 21
致   谢 22
参考文献 23

摘要
 
 利用软件采样法来获取周期模拟信号的数据，并采用一定的计算方法进行数值运算，对信号进行处理，是数字信号处理中常用的一种方法。然而由于采样算法的不尽理想，制约着数字信号处理的准确性。理想的采样方法是均匀同步采样，但是实际采样时，由于受定时器分辨率的影响，实际的采样间隔与理论的采样间隔，存在着截断误差。本文具体介绍了周期信号的三种同步采样法的特点及其在应用中存在的问题，包括双速率同步采样法、偏差累积增量法和参数自寻优等间隔同步采样法，并分析比较各种采样法的优缺点。本文阐述了通过软件同步采样来提高周期信号分析精度的算法。同时对周期信号同步采样误差以及软件同步采样方法的频域特性进行了分析。另外，本文还对软件同步采样方法作了进一步探索，介绍了一种用较低采样频率对高频率周期信号进行采样的方法，能够使用远远低于被采样信号频率的采样频率达到与高频率采样同样的效果。
关键词 软件同步；双速率；偏差累积；参数自寻优
 
Abstract
 
 Obtaining the data of cycle analog signal by using software sampling method, and performing numerical operation to process signal by using a certain calculation method, is a method commonly used of digital signal processing. However, the sampling algorithm is not quite ideal, which restricts the accuracy of digital signal processing. The ideal sampling method is uniform synchronous sampling, but in actual sampling, because of the impact of the timer resolution, there is a truncation error between actual sampling interval and theoretical sampling interval. This thesis details the characteristics of three synchronous sampling methods of the periodic signal and its existing problems in the application, including double rates synchronous sampling method, the deviation cumulative incremental method and parameters of self-optimizing equal interval synchronous sampling method, and analyzes the advantages and disadvantages of various sampling methods. The thesis also details on how to improve the accuracy of periodic signal analysis algorithms through software synchronous sampling methods. At the same time, the thesis analyzes the error of periodic signals synchronous sampling and the frequency domain characteristics of the software synchronous sampling methods. In addition, the thesis further explores the software synchronous sampling methods, introduces a way of using lower sampling frequency for high frequency periodic signal, which can receive the same result of high-frequency sampling through using far less than the frequency of the sampled signal.
Keywords software synchronization; double rates; deviation cumulative; parameters of self-optimizing