题目名称：音频信号分析仪（A 题） 摘要： 本音频信号分析仪由 32 位 MCU 为主控制器，通过 AD转换，对音频信号进行采样，把连续信号离散化，然后通过 FFT 快速傅氏变换运算，在时域和频域对音频信号各个频率重量以及功率等指标进行分析和处理，然后通过高分辨率的 LCD 对信号的频谱进行显示。该系统能够精确测量的音频信号频率范围为 20Hz-10KHz，其幅度范围为 5mVpp-5Vpp，分辨力分为 20Hz 和 100Hz 两档。测量功率精确度高达 1%,并且能够准确的测量周期信号的周期，是理想的音频信号分析仪的解决方案。关键词： FFT MCU 频谱 功率 Abstract: The audio signal analyzer is based on a 32-bit MCU controller, through the AD converter for audio signal sampling, the continuous signal discrete, and then through the FFT fast Fourier transform computing, in the time domain and frequency domain of the various audio frequency signal weight and power, and other indicators for analysis and processing, and then through the high-resolution LCD display signals in the spectrum. The system can accurately measure the audio signal frequency range of 20 Hz-10KHz, the range of 5-5Vpp mVpp, resolution of 20 Hz and 100 Hz correspondent. Power measurement accuracy up to 1%, and be able to accurately measuring the periodic signal cycle is the ideal audio signal analyzer solution.Keyword: FFT MCU Spectrum Power1 方案论证与比较......................................................................................................31.1 采样方法方案论证..........................................................................................31.2 处理器的选择方案论证..................................................................................31.3 周期性判别与测量方法方案论证..................................................................32 系统设计..................................................................................................................42.1 总体设计.................
