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通信電子]基于gprs遠(yuǎn)程監(jiān)控系統(tǒng)數(shù)據(jù)終端的研究外文資料翻譯-免費(fèi)閱讀

  

【正文】 4003rd regard for the Baud Rate Setting 38400b/s, default values for 9600b/s. AT+CGCLASS= B。 傳輸數(shù)據(jù) 網(wǎng)絡(luò)協(xié)商之后即可進(jìn)行數(shù)據(jù)傳送, GPRS 網(wǎng)絡(luò)支持 TCP/IP 協(xié)議,所以通過(guò)收發(fā)IP數(shù)據(jù)包來(lái)傳送數(shù)據(jù),此時(shí),終端系統(tǒng)向 GGSN 發(fā)送的所有包含 IP 報(bào)文的 PPP 報(bào)文都會(huì)被傳送給 Inter 網(wǎng)中相應(yīng)的 IP 地址,從而完成終端系統(tǒng)向遠(yuǎn)程監(jiān)控中心通過(guò)互聯(lián)網(wǎng)傳輸數(shù)據(jù)的過(guò)程 。 終端軟件設(shè)計(jì) 數(shù)據(jù)終端必須具備以下基本功能:自動(dòng)登錄 GPRS 網(wǎng)絡(luò),自動(dòng)向數(shù)據(jù)中心注冊(cè)動(dòng)態(tài) IP 地址和 SIM 卡的 IMSI 號(hào),進(jìn)行數(shù)據(jù)傳輸。工業(yè)的遠(yuǎn)程數(shù)據(jù)采集系統(tǒng)就 是一個(gè)比較典型的頻發(fā)小數(shù)據(jù)量的實(shí)時(shí)傳輸系統(tǒng)。 GPRS(通用分組無(wú)線(xiàn)業(yè)務(wù)) , 作為 當(dāng)前的 GSM網(wǎng)絡(luò)向第三代移動(dòng)通信 技術(shù)轉(zhuǎn)換的過(guò)渡技術(shù)( )具有接入 快 速、 時(shí)刻 在線(xiàn)、按流量計(jì)費(fèi)等 優(yōu) 點(diǎn),在遠(yuǎn)程突發(fā)性數(shù)據(jù) 及 時(shí)傳輸中有 不可比擬 的優(yōu)勢(shì)。 2 GPRS 技術(shù) GPRS( General Packet Radio Service)通用分組無(wú)線(xiàn)業(yè)務(wù),是在 GSM 系統(tǒng)的基礎(chǔ)上建立的移動(dòng)網(wǎng)絡(luò)系統(tǒng),他使用分組交換技術(shù),能兼容 GSM,并 且能 在網(wǎng)絡(luò)上傳輸高速數(shù)據(jù), GPRS 在傳統(tǒng)的 GSM 網(wǎng)絡(luò)中引入了 3個(gè)新的 器件 : PCU( Packet Control Unit,分組控制單元)、 SGSN( Serving GPRS Support Node, GPRS 服務(wù)支持節(jié)點(diǎn))和 GGSN( Gateway GPRS Support Node, GPRS 網(wǎng)關(guān)支持節(jié)點(diǎn)) , GPRS 通信具有以下特點(diǎn): 資源利用率高 GPRS 引 進(jìn) 了分組交換的傳輸模式,用戶(hù)只有在發(fā)送或接收數(shù)據(jù)期間才占用資源,這 就是說(shuō) 多個(gè)用戶(hù)可高效率地共享同一無(wú)線(xiàn)通信,從而提高了資源的利用率,而 GSM 傳輸數(shù)據(jù)方式為電路交換模式,在整個(gè)連接 時(shí) 期內(nèi),用戶(hù)無(wú)論是否傳送數(shù)據(jù)都將獨(dú)自占用無(wú)線(xiàn)信道。 3 系統(tǒng)設(shè)計(jì) 系統(tǒng)結(jié)構(gòu) 整個(gè)系統(tǒng)的結(jié)構(gòu)如圖 1所示 。 串口驅(qū)動(dòng) 由于數(shù)據(jù)終端是用單片機(jī)實(shí)現(xiàn)的,必須從底層的串口通信開(kāi)始逐漸實(shí)現(xiàn) GPRS登錄,最終實(shí)現(xiàn)數(shù)據(jù)的傳輸,串口驅(qū)動(dòng)實(shí)現(xiàn)打開(kāi)串口( OpenComm)、關(guān)閉串口( CloseComm)、讀串口數(shù)據(jù)( ReadComm)、向串口寫(xiě)數(shù)據(jù)( WriteComm)、串口中斷( Interrupt UartRxISR)等。 系統(tǒng)實(shí)現(xiàn)的一個(gè)難點(diǎn)是登錄 GGSN 的過(guò)程,即終端系統(tǒng)登錄 GPRS 網(wǎng)關(guān)( GGSN)并與網(wǎng)關(guān)通過(guò) LCP, PAP, IPCP 協(xié)議進(jìn)行協(xié)商的過(guò)程。 4003rd mobile terminals for the B category, with GSM and GPRS Inter voice function, However, they can not use that can automatically switch.. AT+CGDCONT=1, IP, CMNET。s lives has undergone a profound 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 munications technology development in the field of remote monitoring. GPRS (General Packet Radio Service), as the existing GSM work evolution of the transition to the third generation mobile munication technology for (), with rapid access, always online, so by the flowmeter features Remote realtime data transmission in a sudden unmatched advantages. 2 GPRS technology GPRS (General Packet Radio Service) is based on the GSM mobile work systems, the use of packet switching technology, patible with GSM, and highspeed data transmission works, GPRS in the GSM work to introduce a traditional three new ponents : 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) wi
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