龚帅杰 外文翻译.docVIP

外文： Long-distance supervisory system data terminal research Based on GPRS 1 introduction With the development of computer technology, Internet technology is particularly extensive and in-depth various aspects of peoples lives. make peoples lives has undergone a profound change.As industrial areas, because of the need to control areas, monitoring of a wide range of objects, hence the need to spend a lot of manpower, material and financial resources for equipment maintenance. Moreover, there are many adverse conditions, it is not easy to stay the occasional moment of arrival or not some field data collection. If the amount of wiring work it is not the economy, is unreasonable. This has helped wireless communications technology development in the field of remote monitoring.  GPRS (General Packet Radio Service), as the existing GSM network evolution of the transition to the third generation mobile communication technology for (2.5G), with rapid access, always online, so by the flowmeter features Remote real-time data transmission in a sudden unmatched advantages. 2 GPRS technology GPRS (General Packet Radio Service) is based on the GSM mobile network systems, the use of packet switching technology, compatible with GSM, and high-speed data transmission networks, GPRS in the GSM network to introduce a traditional three new components : PCU (Packet Control Unit, a control unit). SGSN (Serving GPRS Support Node. GPRS service node support) and GGSN (Gateway GPRS Support Node. Gateway GPRS support node) with the following characteristics : The high utilization rate of resources to the introduction of the GPRS packet switching mode of transmission, Only users send or receive data only during the occupation of resources This means that many users share the same wireless communications and high efficiency, thereby increasing the utilization of resources. GSM circuit switched data transmission methods and models for the entire link period, Whether