The project provides you simple example of the principle signal processing. You can find more details about how to use these code in CSDN blog "信号处理趣学" 。 The author is CSDN bloger "狂小虎". The codes are .m files, and you can run them in MATLAB.
信号处理趣学D7——自功率谱的物理意义&通过自功率谱分析原信号的简谐分量
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