中文说明：
这是一个用FDTD算法计算二维金属方柱散射场RCS的matlab程序。采用UPML吸收边界条件和高斯脉冲源激励，对于学习FDTD方法中的激励源加入，近-远场外推，吸收边界设置等很有帮助。
English Description：
This is a matlab program for calculating the RCS of two-dimensional metal square cylinder scattering field with FDTD algorithm. Using UPML absorbing boundary condition and Gaussian pulse source excitation is very helpful for learning the excitation source addition, near-far field extrapolation, absorbing boundary setting and so on in FDTD method