The Application And Implementation Of Mapx And Gps Technology In Cmmb Signal Tester

This paper introduces the background knowledge and theories of GPS and MapX technology,and then establish the GPS navigation system based on MapX by using VC++6.0. It can achieve real-time tracking to the navigation target and can store and manage the locating information of the navigation target by using Access database and DAO technology. This paper includes the following:1. achieve some of the basic function of the map by using MapX electronic map which created by VC++;2. realize the serial communication between the computer and the GPS module by using multiple threads and MSComm control technology;3. get the navigation targets'latitude and longitude information by analyzing the GPS information data, and store and manage the data by using Access database technology;4. achieve dynamic tracking to the navigation target and real-time display the location of the navigation target on the electronic map by combining the GPS and MapX technology;5. store the action path of the navigation target and realize the echo path on the electronic map by using Access database and MapX technology;6. achieve the conversion between the screen coordinates and geographic coordinates, and on this basis, design and realize the Overview Map function;7. get the CMMB Signal Strength Distribution Chart by combine the system and CMMB Signal System, so that the users are clear the trends of the CMMB signal strength at a glance.Field tests proved that the system is highly scalable and versatile. It also has a high practical value and social value. Test results show that the system runs stable, reliable, achieves the real-time display of the navigation targets'position, dynamic tracks the navigation target. This system was used in the products"CMMB Signal System"in our laboratory, and it has achieved the desired results. It also proves the value of this research as well as the practicality of this navigation system.