GSM Downlink Simulation And It’s DSP Implementation

GSM mobile communication system is the second generation of mobile communication system,and it is widely used in various fields of national economy.GSM mobile communication system is using the frequency hopping,authentication and encryption technique to ensure the safety of the mobile users’ communication.The main content of this dissertation is to explore the down link of the GSM mobile communication system,the research focus on that based on the broadcast channel,common control channel and dedicated control channel,how to deliver messages between the pseudo base station and the mobile station after the mobile station power on.In practical applications,the messages which the pseudo base station send to downlink are continuously,so after the mobile station power on,the first step of the task is to complete the synchronization between the pseudo base station and mobile station by the frequency correction channel and the synchronization channel,and then receive the system’s messages which come from the broadcast channel,and the last is to launch the channel request by the random access channel,while we start to update the position,base on these steps we can complete the mobile station’s resident within the coverage areas of the pseudo base station.We construct the simulation platform for the update of simulation position based on VC6.0,this platform not only can achieve the simulation of down link,but also can analysis the received messages directly.At the same time help the partner to complete DSP software design of the GSM downlink.