自写曲率计算函数 ,非归零型差分相位调制信号建模与仿真分析 ，包括最小二乘法、SVM、神经网络、1_k近邻法。- Since writing the curvature calculation function, NRZ type differential phase modulation signal modeling and simulation analysis, Including the least squares method, the SVM, neural networks, 1 _k neighbor method.