说明：  该程序用于测量频谱。比如可以从扬声器上产生白噪声，用麦克风接收，接收到的数据经过处理便可以生成一个频谱图，程序中带有滤波器。
(The procedures used to measure the spectrum. White noise, for example, can be generated from the speaker with microphone receiver, the received data can be treated to generate a spectrum chart, the program with the filter.)