The Research Of Data Compression On Abis Interface Of GSM Network

On the Abis interface which is between BSC(Base Station Controller) and BTS(Base Transceiver Station), the throughput of data is fixed at 2Mbps. As networks become larger and larger, and there are more and more uesrs, signals may be blocked and data may be lost at network when it is busy. And since the half rate technology has been widely used, the bandwidth of the LAPD(Link Access Protocol on the DM Channel) on the Abis interface is becoming limited. As the reason given above, it is very important and useful to increase the throughput of the Abis interface.In order to double the throughput of the Abis interface, the software compression technology is used, which is always used in upper layer of OSI model.This paper proposed a new compression algorithm called LZ77++, taking considering of the latest GSM transport protocol, characteristics of data in the Abis interface. Data in Abis interface is de-muxed and compressed at one side. And the data will be muxed and decompressed at the other side.The proposal described in this paper has been implemented in the A-Bis over IP Gateway system of BroadBand High Technology Inc. The experiemental result has proven that it could increase the throughput of the Abis interface significantly, and it is worthy for further research.