| With the rapid development of the wireless communication technology to the direction of integrated, small and modular today, distributed base station marks the basic development idea of "the next-generation of base stations". Distributed base station can make the balance between high performances and low cost, which has the capability to be distributed flexibly, and it conforms to the overall communications industry trends. At present the most representative international 3G mobile communication technology standards CDMA2000, TD-SCDMA and WCDMA, and WCDMA has inherent advantages on market, higher spreading gain and global roaming capability, which make WCDMA distributed base station become the hot research field of the current communications problems.Embedded systems have been integrated into daily life, and the density of main memory is rising, while prices are decreasing. And embedded memory database can meet the current situation of shortage of embedded system hardware resources and the requirements of real-time efficiency. So applying the embedded memory database technology to WCDMA distributed base station system to resolve the data real-time synchronization and main/standby switch problems has a very good prospect.The following aspects were proposed in this paper:1,3G base station software platform architecture was introduced in this paper, and this platform is based on embedded real-time operating system VxWorks. This software platform can shield the hardware environment, and support various business software applications, and also support the smooth switching between various embedded operating systems.2,Embedded memory database system for WCDMA distributed base station was proposed, which is to provide real-time, stable and reliable data management and maintenance for the whole system, including data interfaces for other applications, real-time synchronization and reliable main/standby switch. The database system includes the following modules:system power module, fore-background synchronization module, main/standby synchronization module, data saving module, trigger module and data interfaces module. This paper focuses on the algorithms of the fore-background's data synchronization; the main/standby data synchronization and switch of this embedded memory database for WCDMA distributed base station.3,In order to achieve the fore-background real-time data synchronization in WCDMA distributed base station, record-level synchronization algorithm and table-level synchronization algorithm were respectively proposed for situations of single table multiple tables operation by the baceground, which were both based on the main/standby memory idea. The outstanding advantages of the two algorithms were taking into account the parent-child relationship constraint and the exclusive table constraint, which can completely avoid the illegal data synchronization. Experiments proved that this two algorithms have very good real-time nature, and the algorithms can also apply to other distributed base station systems which have fore-background operations.4,In order to improve the reliability of communication systems,1+1 main/standby mechanism is usually applied, which is also used in WCDMA distributed base station. So the realization of main/standby data synchronization and switch is the key of stability of the communication system, and main/standby switch includes main/standby data synchronization.The proposed algorithm is different from the main/standby switch algorithms, which were proposed before. On the one hand, the algorithm does not rely on base station hardware device, which is dependent on the software, and it is portable and greatly reducing the hardware overhead; On the other hand, the algorithm also different from proposed ones by software, it changed the order of main/standby switch, which can avoid two standbys state, and data synchronization is operated before the switch phase, which can greatly reduce the switching time. And the algorithm is suitable for multi-mode communication system, which can adapt well to the future prospects. |
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