时频分析，一个频率为100的正弦信号做WVD时频分析,做出图后有两个频率(100Hz和400Hz)-Time-frequency analysis, a sinusoidal signal with a frequency of 100 do WVD time-frequency analysis, make a diagram after the two frequencies (100Hz and 400Hz)

基带信号位一个150-400HZ内，幅度随频率逐渐递减的音频信号。-In a baseband signal 150-400HZ, gradually decreasing the amplitude versus frequency of the audio signal.

比例谐振（PR）控制在逆变电源中的仿真，控制器采用PR控制器，电压外环，电流内环的LABVIEW仿真。输出115V/400Hz交流电- U6BD4 u4F8 u8C0 u632F uFF08PR uFF09 u63A7 u5236 u5728 u9006 u53D8 u7535 u6E90 u4E2D u7684 u4EFF u771F uFF0C u63A7 u5236 u5668 u91C7 u7528PR u63A7 u5236 U56

利用自相关或平均幅度差提取基音原理，帧长160，帧移80。求能量E、过零率Z和基音周期pitch；采用自相关法或平均幅度差法求取基音周期，基音周期范围（80~400hz）；画出能量、过零率和基音曲线。(Pitch principle is extracted by means of autocorrelation or mean amplitude difference)