dsp音频信号分析仪.docVIP

基于DSP的音频信号分析仪 摘 要 音频信号分析被广泛用于测量各类音频信号的时域特性、频域特性及其失真特性等，在生产实践和科学研究中有着广泛的应用，而进行比较完整的音频测试分析需要购置各种价格昂贵的专用仪器。随着快速傅里叶变换（FFT）算法和DSP芯片的出现和发展，它们为各式各样的频率问题提供了一个统一的、经济的、单片集成的解决方法，将DSP技术应用到音频分析的设计与制造中，更是给音频分析仪的设计带来了全新的面貌。 本文首先对音频信号的时域处理方法进行分析，在对音频信号的频谱方法研究以及与其他设计方案进行了比较的基础上，提出了一种基于DSP的音频信号分析仪的构思。之后介绍了基于DSP的音频信号分析仪所涉及的各种相关原理，提出了其基本思路是：由DSP芯片TMS320C5402为数据处理器，STC89C51引导并控制DSP芯片，前端音频信号经放大滤波和16位的声卡采样后，DSP芯片对音频信号进行1024个点的实时FFT变换，对音频信号的主频成分进行实时分析，把结果通过HPI总线传给STC89C51进行处理，通过串口传给计算机，在计算机上进行显示。取得较为满意的效果，验证了该系统的可行性。 关键词：音频信号分析仪，数字信号处理，快速傅氏变换，STC89C51，频谱分析 DSP-based audio signal analyzer ABSTRACT Audio signal is widely used to measure all kinds of audio signal character of time domain, the frequency domain properties and its characters of distortion. It is widely used in the production practice and scientific research. But undertake complete audio test analysis needed to purchase all kinds of expensive special apparatus. Along with the fast Fourier transform (FFT) algorithm and digital signal processor (DSP) to emerge and development, they for all kinds of frequency provides a unified, economic, monolithic integrated solutions, DSP technology is applied to the audio analysis of the design and manufacture, is given to the design of the audio analyzer has brought a new look. This paper first analysis the audio signal processing methods of time domain, com- pared with audio signal spectrum research and other design schemes, put forward the conception that based on DSP audio signal analyzer. After the introduction of the audio signal analyzer based on DSP involved all sorts of relevant principle, puts forward the basic idea is: by DSP TMS320C5402 for data processor, STC89C51 to lead and control DSP chip, and at the front end audio signal through enlargement filter and 16 sound card sampling, DSP chip for audio signal 1024 points of real-time FFT transform, for audio signal the main frequency components for real-time analysis, the results through the HPI bus to STC89C51 processing