中文说明：
介绍了喷泉码中LT 码的编码译码过程，提供了详细的MATLAB 仿真代码和说明. 通过对三种不同度分布的LT 码进行性能仿真，并对仿真结果进行了分析，同时也对LT 码和Raptor 码进行了适当的比较。
English Description：
This paper introduces the encoding and decoding process of LT codes in fountain codes, and provides detailed matlab simulation codes and instructions. Through the performance simulation of three LT codes with different degree distributions, the simulation results are analyzed, and the LT codes and Raptor codes are properly compared.