说明：  本文首先说明了本次课程设计的目的和软硬件环境，然后介绍了J-Sim的编译与配置；接下来，在第四章说明了无线传感器网络各结点的内部结构图，第五章和第六章是我们对J-Sim中无线网络包和传感器网络包所做的总体分析，在阅读第五章和第六章之前，需要先阅读第四章，理解各结点的内部结构图。最后，我们对一个简单的无线传感器网络进行了仿真
(The paper first describes the purpose of curriculum design and hardware and software environment, and then introduced the J-Sim and disposition of the compiler Next, in the fourth chapter describes the wireless sensor network node' s internal structure, in Chapter V and Chapter VI is the J-Sim package of wireless networks and sensor networks made the overall package analysis, read Chapters V and VI before the need to read the fourth chapter, understanding the internal node structure. Finally, we have a simple wireless sensor network simulation)