Impulse Response Determination by Cross Correlation
Impulse Response Determination by Cross Correlation
复制标题
通过互相关确定脉冲响应
DOI：
--
复制
发表时间：
1970
影响因子：
4.4
通讯作者：
Elmer M. Mitchell
中科院分区：
文献类型：
--
作者：
R. Polge;Elmer M. Mitchell
本文介绍了一种数字交叉相关器的设计及其在确定线性系统脉冲响应中的应用。将受噪声激励的线性系统的输入和输出相关联的交叉相关器的输出与线性系统对脉冲的响应相同，该脉冲与噪声自相关相同。脉冲响应误差定义为实际脉冲响应与真实脉冲响应的归一化均方差。数字计算机仿真证实，当输入矩形脉冲的宽度等于噪声自相关函数的宽度时，传统技术与相关技术产生相同的脉冲误差。讨论了数字相关器的工作原理和设计。与通用数字计算机相比，专门设计的数字相关器的一个优点是可以实时运行，没有软件和存储问题。实验和数字计算结果表明，即使存在扰动，数字相关器也能准确地确定脉冲响应。只有相关技术才能在不干扰系统正常运行的情况下测量系统的脉冲响应。提出了简化设计和提高速度（带宽能力）的建议。
This paper describes the design of a digital cross correlator and its application in determining the impulse response in linear systems. The output of the cross correlator, which correlates the input and the output of a linear system excited by noise, is the same as the response of the linear system to a pulse which is identical to the noise autocorrelation. The impulse response error is defined as the normalized mean-square deviation of the actual from the true impulse response. A digital computer simulation confirms that the conventional technique yields the same impulse error as the correlation technique, when the width of the input rectangular pulse is equivalent to the width of the noise autocorrelation function. The operation and design of the digital correlator are discussed. An advantage of the specially designed digital correlator over a general-purpose digital computer is to operate in real time without problems of software and storage. The presented experimental and digitally computed results show that the digital correlator can accurately determine the impulse response, even in presence of perturbations. Only the correlation technique allows measurement of system impulse response without disturbing normal operation. Suggestions are made to simplify the design and improve the speed (bandwidth capability).