GPS L2C频段的信号仿真和捕获，包括L2C cm(短码)和cl（长码）的产生及融合，以及最后的捕获获取初始频偏和码相位-GPS L2C signal simulation and capture band, including L2C cm (short code) and cl (long code) generation and integration, and finally get the initial capture and code phase offset