摘要
介绍了音频信号分析仪的硬件结构和软件设计。该设计在MATLAB计算、仿真的基础上,搭接了以单片机MSP430F5438为核心器件的控制电路,利用快速傅里叶变换(FFT)的方法对采集的音频信号进行频谱、功率值、正弦信号失真度等分析。该系统能够精确测量频率范围为20 Hz^10 k Hz,其幅度范围为100 m Vpp^5 Vpp的音频信号,频率分辨率达到20Hz,检测出的各频率分量的功率之和不小于总功率值的95%,单个频率功率误差小于7%,并能够准确地判断输入信号的周期性或非周期性,提供了较为理想的音频信号分析仪的解决方案。
This article introduces the hardware architecture and software design process of the audio signal analyzer. On the foundation of MATLAB computation and simulation, MSP430F5438 MCU is taken as the core to design the control circuit and the fast Foumier transformation (FFT) method is used to analyze the frequency spectrum, power value and distortion degree of the sampled signal. This system can be used to preciously measure the frequency range and the amplitude range of the audio signal. Its frequency resolution is high and its meacurement error is little. Furthermore, the analyzer can be used to accurately discriminate the periodicity or aperiodicity of the input signal. The ideal solution is provided for the audio signal analysis.
出处
《机械制造与自动化》
2015年第6期185-188,共4页
Machine Building & Automation