基于gprs模块的应用设计大学生毕业论文(设计)(设计).doc
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摘 要
GPRS(通用分组无线电业务)是利用包交换的概念发展的一套无线传输方式。GPRS网络是基于现有的GSM(全球移动通信系统)网络实现的。在现有的GSM网络中需要增加一些节点,如GGSN(GPRS网关支持节点)和SGSN(GPRS服务支持节点)。SGSN的主要作用是记录移动终端的当前位置信息,并且在移动终端与GGSN之间完成移动分组数据的发送和接收。GGSN主要起网关作用,可以与多种不同的数据网络连接,如ISDN(综合业务数字网)、PSPDN(包交换公用数据网)和LAN(局域网)等。GGSN可以把GSM网中的GPRS分组数据包进行协议转换,从而把这些分组数据包传送到远端的TCP/IP或X.25网络。
GPRS网不但具有覆盖范围广、数据传输速度快、通信质量高、永远在线和按流量计费等优点,而且其本身就是一个分组型数据网,支持TCP/IP协议,可以直接与Internet互通。因此,CPRS在无线上网、环境监测便携型、交通监控、移动办公等行业中具有无可比拟的性价比优势。
系统软件采用C语言编写,在环境下编译。由于本系统是远程管理终端的一个模块,因此在程序的编写中要遵守一定的协议,这样才能保证正确通信。程序的主体是如何控制GR47的AT命令对GR47进行初始设置和对信息数据的处理。程序总体上可以分为以下几个块:CPRS连接的初始设置、短消息的判断处理、无数据传输时的心跳处理、数据判断转发等。主程序是把这些程序块有机结合到一起,相互控制,无限循环Abstract
GPRS (general packet radio service) is the use of packet switching, the concept of the development of a set of wireless transmission mode. GPRS network is based on the existing GSM (global system for mobile communications) network. Need to add some nodes in the existing GSM network, such as the GGSN (GPRS gateway support node) and SGSN service (GPRS support node). SGSNs main function is to record the current position of mobile terminals, and mobile packet data between mobile terminal and the GGSN in sending and receiving. GGSN main gateway role, with a variety of data network connection, such as ISDN (integrated services digital network), PSPDN (packet switching public data network) and LAN (local area network (LAN), etc. GGSN can put GSM GPRS packet in the packet, protocol conversion, thus the packet packets to the remote TCP/IP or x. 25 network.
GPRS network not only has wide coverage, data transmission speed, high communication quality, always online and charged according to traffic advantages, and its type is itself a packet data network, support TCP/IP protocol, can be directly exchanged with the Internet. As a result, the CPRS in portable wireless Internet access, environmental monitoring, traffic monitoring, mobile office, etc have an unparalleled price advantage.
System software using C language to write, compile under VB
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