非归零型差分相位调制信号建模与仿真分析 ，多元数据分析的主分量分析投影，实现了图像的加水印，去噪，加噪声等功能。- NRZ type differential phase modulation signal modeling and simulation analysis, Principal component analysis of multivariate data analysis projection, Realize image watermarking, de-noising, p