用Fourier變換求取信號的功率譜---周期圖法
用Fourier變換求取信號的功率譜---分段周期圖法
用Fourier變換求取信號的功率譜---welch方法
功率譜估計----多窗口法（multitaper method ,MTM法）
功率譜估計----最大熵法（maxmum entmpy method,MEM法）
功率譜估計----多信號分類法（multiple signal classification,music法）Fourier transform to strike a signal to the power spectrum - the cycle of plans
Fourier transform to strike a signal to the power spectrum - Sub-cycle Method
Fourier transform to strike a signal to the power spectrum --- welch method
Power spectrum estimated more than window ---- Law (multitaper method, MTM)
---- Power spectrum estimate of maximum entropy (maxmum entmpy method, MEM)
---- More than the estimated power spectrum signal classification (multiple signal classification, music)
替代加密:
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I HAVE A DREAM！#
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用ARM編程實現替代加密。
