.800 Mhz Cdma Fiber Optic Repeater Design And Realization

One of the key problem of CDMA mobile communication system has to settle is the coverage efficiency. In the beginning of CDMA system construction, some area can not be covered because of lacking Base Stations.,and also in special places such as underground and tunnels. So one good solution for wireless network optimization is necessary. Repeater is one relay station. Repeater can be grouped under wireless repeater and fiber-optic repeater.. At first, the paper put forward one scheme and develop one type of 800M Hz CDMA fiber-optic repeater which bases on theory analyze and requirement. Secondly, we developed the network control unit. The network control unit select AMTEL AT89C52 as the master CPU and programmed with assembly langue. It has good function and executive efficiently. The network control unit can control interior modules function, such as power control, switch control and alarm disposal. The two network control units in the system need to intercommunicate. At the same time, the network control unit can communicate with outer network control center in a manner of serial communication. The outer network control center can implement parameter setting, data query and alarm disposal. This part is designed by standard interface which is prescribed by China Unicom and has good compatibility. As we see, the design and use of network control unit meet the needs of administrable and controllable for CDMA repeaters, and it is a new character of the new generation repeater. On the other hand, The system debugging ,testing and result analyze was performed after system integration. The influence of system noise figure and intermodulation caused by repeaters to base station are analyzed. Some solutions are put forward. According to the application of this type CDMA repeater, we can see that this type repeater is viable and effective both in theory and technique.