摘要
利用数字系统来实现数字音频测量系统中的正交检波分析,其关键在于如何选取当分析待测正弦信号中频域特性时的窗函数。在研究过程中,主要运用了BH窗、Blackman窗、三阶矩形自卷积窗和四阶矩形自卷积窗,同时使用Matlab进行了数值仿真计算,从而获得窗函数类型和加窗长度对于幅度及相位分析精度的影响,得出在数字音频测量系统中研究频率响应和失真时加余弦窗得到的精度比加矩形自卷积窗要高,这对保证测量结果的精确性很重要。为正弦稳态分析方法的正确使用提供了有意义的理论指导。
The orthogonal detection analysis of the digital audio measurement system was implemented by digital systems. The selection of window function is key step when the frequency domain characteristics of sinusoidal signal under test is ana- lyzed; In the process of the study, BH window, Blackman window, third-order convolution rectangular windows and four-order convolution rectangular window are employed, and the numerical simulation calculation is performed with Matlab. The effect of window function types and windowing function length on the extent and accuracy of the phase analysis is obtained. When the digital audio-frequency response and distortion of the digital audio-frequency detection system is studied, it is found that the accuracy detected by the cosine window is higher than that detected by the rectangular convolution window. It is important for ensuring the accuracy of measurement.
出处
《现代电子技术》
2010年第17期108-110,共3页
Modern Electronics Technique
关键词
频域特性
窗函数
相位分析
正弦稳态
frequency domain characteristic
window function
phase analysis
sinusoidal steady state
