电子信息毕业论文话筒频谱特性测量仪设计技术方案.docVIP

摘 要 频谱仪作为一种常用测量工具，广泛的使用在测试计量领域的各个方面，用于射频和微波信号的频域分析，包括测量信号的功率，频率，失真产物等等。现代频谱分析仪能以模拟方式或数字方式两种方式显示分析结果，能分析1赫以下的甚低频到亚毫米波段的全部无线电频段的电信号。此仪器内部采用数字电路和微处理器，具有较强的存储和运算功能，配置标准接口，很容易构成自动测试系统。话筒作为一种常见的接收音频信号的终端设备，话筒分为动圈话筒和电容话筒两大类。其频谱特性对语音识别等研究具有重要价值，因此很多方面都需要话筒。 本文设计了一套简易的话筒频谱测量仪，介绍了以STM32为核心的FFT变换的软件编程来实现对采集到的信号进行频谱的分析，可以实现幅值在0-5V的不同频率输入的音频信号频谱分析。另外系统带有显示功能，可利用液晶模块显示频谱测量结果，可以方便分析。本系统通过揭示信号频率成分特征，可作为语音识别和噪声监测等领域的分析工具，在实际生活中用着重要的实用价值，具有较好的研究价值和应用前景。 关键词：音频；频谱；STM32；快速傅里叶变换 Abstract Spectrum analyzer as a common measurement tool, widely used in all aspects of the test field of metrology, for the frequency domain RF and microwave signal analysis, including measurement signal power, frequency, distortion products, and so on. Modern spectrum analyzer can display the results in an analog mode or digital mode in two ways, one can analyze the following Hz VLF radio frequency band to all electrical sub millimeter band. This instrument uses the internal digital circuits and microprocessors, with a strong memory and computing functions, configuration of standard interfaces, it is easy to form the automatic test system. Microphone terminal device as a common receiving an audio signal, dynamic microphone into the microphone and condenser microphone categories. Its spectral characteristics of great value in speech recognition research, many aspects need microphones. A simple microphone spectrum measuring instrument was designed, and the software which realizes collected signal spectrum analysis based on the STM32 was introduced in this paper. The signal also can be amplified at 0-5V voltage. The system had display function which display measurement results on lattice Screen. The system can reveal the characteristic frequency signal components can be used as voice recognition and noise monitoring in areas analysis tools, with good research value and application prospects. Key Words: Audio; Spectrum; STM32; FFT 目 录 摘 要 I Abstract II 目 录 III 1. 绪论 1 1.1 研究的意义与前景 1 1.2 研究的原理 1 1.3 论文总体结构安排 2