说明：  仿真源码包括了多层异构蜂窝网络中基于齐次泊松点过程（HPPP）的建模方法，一篇介绍该模型的12年发表在IEEE trans的论文。以及传统六边形建模方法和信道增益矩阵的计算。
(Simulation source code, including the multi-heterogeneous cellular networks based on homogeneous Poisson point process (HPPP) modeling method, a description of the model' s 12-year papers published in IEEE trans. And traditional modeling methods and hexagonal channel gain matrix calculation.)