基于微信小程序的语音频谱分析实验教学系统设计

Design of speech spectrum analysis experimental teaching system based on WeChat applet

为解决高校电子信息类专业通信类课程教学实验时长受限、地点受限等问题,帮助学生更好地理解频谱分析原理,开发基于小程序的信号发生器与频谱分析仪,利用互联网的优势,实现随时开展实验教学的效果。信号发生器可产生一定频率范围内的正弦波、方波、三角波、随机噪声、洛伦兹脉冲以及辛普森脉冲共6种常用的信号,并通过手机扬声器或耳机孔输出;频谱分析仪可对手机麦克风接收到的语音进行加窗频谱分析,并把频谱结果展现在屏幕上。使用固定型号手机进行测试,结果表明,信号发生器在产生100 Hz~10 kHz的正弦波时频率相对误差为0%,产生其它波形的频率相对误差≤1%;频谱分析仪在对正弦波音频输入做频谱分析时,峰值频率测量误差在5 Hz以内,具有良好的实验教学指导意义与现场应用适用性。

In order to solve the problems of limited duration and location of communication experiments of the Electronic Information Specialty in Universities and help students better understand the principle of spectrum analysis,a small program-based signal generator and spectrum analyzer were developed,and the advantages of the Internet were used to realize the effect of conducting experiments at any time.The signal generator can generate 6 kinds of commonly used signals including sine wave,square wave,triangle wave,random noise,Lorentz pulse and Simpson pulse in a certain frequency range,and output them through the mobile phone speaker or headphone jack.The speech received by the microphone is subjected to windowed spectral analysis,and the spectral results are displayed on the screen.Using a fixed type of mobile phone to test,the results show that the relative error of the frequency of the signal generator is 0% when generating a sine wave of 100 Hz to 10 kHz,and the relative error of the frequency of other waveforms is less than 1%.During spectrum analysis,the peak frequency measurement error is within 5 Hz,which has good experimental teaching guiding significance and field application applicability.