非归零型差分相位调制信号建模与仿真分析 ，使用大量的有限元法求解偏微分方程，内含心电信号数据及运用MATLAB写的源代码。- NRZ type differential phase modulation signal modeling and simulation analysis, Using a large number of finite element method to solve partial differential equations, ECG data and includes source code written in MATLAB.