题目名称:数控直流电流源(F[键入文档副标题]题目名称:音频信号分析仪(A题)华南理工大学电子与信息学院参赛队员:陈旭张洋林士明摘要: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分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:FFTMCU频谱功率Abstract:Theaudiosignalanalyzerisbasedona32-bitMCUcontroller,throughtheADconverterforaudiosignalsampling,thecontinuoussignaldiscrete,andthenthroughtheFFTfastFouriertransformcomputing,inthetimedomainandfrequencydomainofthevariousaudiofrequencysignalweightandpower,andotherindicatorsforanalysisandprocessing,andthenthroughthehigh-resolutionLCDdisplaysignalsinthespectrum.Thesystemcanaccuratelymeasuretheaudiosignalfrequencyrangeof20Hz-10KHz,therangeof5-5VppmVpp,resolutionof20Hzand100Hzcorrespondent.Powermeasurementaccuracyupto1%,andbeabletoaccuratelymeasuringtheperiodicsignalcycleistheidealaudiosignalanalyzersolution.Keyword:FFTMCUSpectrumPower1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.....................................................................................................................................42.2单元电路设计.............................................................................................................................52.2.1前级阻抗匹配和放大电路设计.............................................................................................52.2.2AD转换及控制模块电路设计...............................................................................................62.2.3功率谱测量单元电路设计.....................................................................................................63软件设计.............................................................................................................................................74系统测试.............................................................................................................................................85结论.....................................................................................................................................................9参考文献:...............................................................................................................................................9附录:.....................................................................................................................................................