几种基本的预失真功率谱仿真，包括直接法，间接法、bartlett法、welch法-Several pre-distortion power spectrum of the basic simulation，Including direct, indirect method, bartlett law, welch method

功率谱密度估计。welch法功率谱密度估计，协方差法估计，Burg法估计。-psd estimate。welch，covariance，Burg。

多进制矩形成型连续相位信号的产生程序并用welch法求其功率谱-Continous phase modulation signal and it s PDF