直接序列扩频通信系统，实现PN码同步，采用串行滑动相关捕获相关峰-Direct sequence spread spectrum communication system, and PN code synchronization, sliding-related capture serial correlation peak

pn结模拟：一维PN结的模拟 ，有限元法 结合耦合法，新手求交流(Pn junction simulation: one-dimensional pn junction simulation, finite element method combined with coupling method, novice for communication)