GSM系统无线网络的优化

介绍了无线网络优化的基本内容和基本方法,对无线网络指标优化进行了详细的阐述。     

Design and performance of a compact forward-coupled HTS microstrip filter for a GSM system

A practical design technique for a compact forward-coupled microstrip bandpass filter structure is introduced based on a computer-aided simulation and optimization software TUMIC. The structure consists of a parallel array of fully aligned half-wavelength resonators. Aimed at the application in the front-end receiver of a GSM base station, a 9-pole high-temperature superconductor filter with 2.6% fractional bandwidth at 1732.5 MHz was designed and fabricated using double-sided YBCO thin films on a 30-mm/spl times/30-mm/spl times/0.5-mm LaAlO/sub 3/ wafer. The S-parameter measurements show a good agreement with the simulated results. At 30 K, the filter has less than 0.4-dB insertion loss, 0.3-dB passband ripple, and better than 12-dB return loss.     

解决GSM小区拥塞的方法

分析了GSM小区拥塞问题 ,提出解决拥塞问题的几种方法     

基于Internet和GSM的智能家居网关设计与实现

针对智能家居的特点及功能,提出基于Internet和GSM的智能家居网关的设计方案。系统采用三星公司的ARM9芯片S3C2440作为硬件平台,并搭载嵌入式Linux操作系统。通过在ARM9硬件平台上搭建boa服务器,实现家庭内网与Internet的通信。系统重要的报警信息通过手机模组,以短信的形式,及时发送到用户的手机上。经测试,该系统工作稳定,能够实现家庭内网与手机和计算机终端的通信。     

Overview of the GSM system and protocol architecture

The global system for mobile telecommunications (GSM), which provides terminal mobility, with personal mobility provided through the insertion of a subscriber identity module (SIM) into the GSM network, is discussed. Cellular mobile communications, the cellular network infrastructure, and the specification of network databases and standards are described. The GSMs, numbering plan, radio channel structure, mobility management, call routing and signaling, protocol layering architecture, signaling transport protocols, and paging messaging systems are also described     

基于GSM的家庭安全报警系统设计

设计了一种基于GSM电信网络的家庭安全远程报警系统,主要有数据采集模块、单片机STC89C52RC为核心的数据处理模块和TC35i为核心的GSM无线网络接入模块。系统能够实现防盗、防火灾、防漏水、防天然气或煤气泄漏等功能,并能够将报警信息通过GSM网络实时发送至用户和物业管理中心,用户可以通过手机对系统进行远程控制。     

一种GSM光纤室内直放站系统设计与开发

分析研究了一种改进的GSM光纤室内直放站的解决方案和测试系统,主要解决城市群楼区、机场等大型建筑物的移动通信的室内覆盖问题.     

基于GSM和ARM的远程监控系统的研究

本文提出一种GSM短消息的远程监控系统的解决方案,用GSM网络的短消息业务实现了计算机与远程ARM为中心的嵌入式系统的通讯,对远程终端的硬件结构和控制程序设计进行了介绍,研究表明本系统完全可以用于数据流的稳定传送,且可靠性高.     

GSM数字移动通信系统语音信源编解码技术

依据GSM协议,介绍了GSM系统所采用的语音信源RPE-LTP(规则码激励长期预测)编码技术,详细阐述了相应的信源解码模型和解码算法,并在工程实现中对算法性能进行了大量的测试,验证了解码模型的可行性和算法的有效性。     

基于GSM和GPS的车辆异常监控系统设计

针对在车辆运输过程中可能出现的路线异常和时间异常的情况,提出一种基于GSM和GPS的车辆运输异常监控系统设计方案,该系统具有自动检测及报警功能。另外,由车载单元自行进行检测、判断与报警的运行模式,改变了传统以监控人员对车辆进行监视和分析的模式,从而降低人力资源成本,提高了系统的智能化水平。实践表明,该系统具有开发成本低,扩展性好,可靠性高等特点。     

KISS-16V2: a one-chip ASIC DSP solution for GSM

Outlines the requirements for the various digital signal processing functions of the pan-European digital mobile cellular telephone system in terms of computational power and RAM and ROM capacities, and describes a digital signal processor (DSP) solution which is able to integrate all of these digital baseband functions for a hand-held terminal onto one VLSI chip. The KISS-16V2 processor, a low-power CMOS 16-b DSP, is optimized for digital telecommunications, especially for Groupe Speciale Mobile (GSM). A power-down mode together with the capability of memory and multiplier standby operation make this DSP well suited for handheld devices. A design strategy based on the extensive use of cell compilers and synthesis tools reduces the design of further DSP derivations to a minimum.<>     

基于GSM手机的远程无线测控系统设计

在分析SMS短消息工作协议的基础上,对如何利用单片机向手机模块发送AT指令以达到控制手机模块收发短信息的问题进行了较深入的探讨.所设计的系统对应用于工控领域的远程无线数据传输的方法进行了完善和补充,实现了基于GSM网的远程无线测控的目的,具有很高的实用价值.     

基于ZigBee和GSM的高速公路自适应限速系统

为了让驾驶员及时获得不良天气下高速公路车辆限速信息,设计了基于Zig Bee和GSM的高速公路自适应限速系统。系统中MSP430对气象数据进行处理,并根据限速准则计算出当前天气条件下的限速信息,若判断和上1 min计算的值不同则通过GSM网络更新路边装置限速信息。当车辆行驶至路边装置的Zig Bee网络范围内时就会收到限速信息,若限速信息发生变化则车载装置液晶显示并语音播报。测试结果表明:在路边装置Zig Bee网络范围内车载装置能够正常接收到限速信息。     

Internet protocols for multimedia communications. I. IPng-thefoundation of Internet protocols

Surveys recent and current standardization work by the Internet Engineering Task Force (IETF) on Internet communication protocols. The author describes the IPng project and the IPv6 protocol that will form the basis for upper-layer protocols such as resource reservation, transport and application level protocols. The IETF decided in 1992 to develop a new version of the Internet Protocol (IP) because the available address space of IP version 4 (IPv4) will probably run out early in the 21st Century. The need for a new IP version provided the opportunity to redesign the protocol and add new functions     

Overview of GSM: Philosophy and results

The work on GSM, a standardized European second-generation cellular system, was started in 1982 in order to prevent the fragmentation of the first-generation cellular market from continuing into the second generation. The goal was to define a system with open interfaces for Pan-European use that would offer the best compromise between a number of conflicting requirements, such as spectrum economy, high speech quality, low cost, and a large range of services. A broad outline of the novel features is presented, both concerning the architecture of the system and of the services offered, as well as the reasoning behind the more important choices. Finally, some views are presented concerning the future development of GSM and of the third-generation system, the co-called Future Public Land Mobile Telecommunication System, commonly referred to as FPLMTS.     

一种GSM与WCDMA网的协同优化方法研究

为实现GSM与WCDMA网的进一步协同优化,在现有技术的基础上提出了一种新的网络协同优化方案,且在WCDMA到GSM小区重选和WCDMA信号强度过低小区重选过程对该方案进行了验证,结果表明该方法能够较快的完成小区重选的过程,使UE能够以较快的速度进入GSM小区网络,为无线通信技术提供了有力的保障,具有一定的实际应用价值.     

适用于GSM900/GPS系统的双频段低噪声放大器设计

基于SMIC 0.18μm CMOS工艺,设计了一个适用于GSM900和GPS系统的并行式双频段低噪声放大器.电路采用1.8V电源供电,考虑到两级之间的匹配特性,运用了级间电感技术.介绍了输入、输出匹配电路的具体设计方法.运用Cadence中的SpectreRF软件进行仿真,结果表明,增益特性S21在两个频段均大于10...     

应用于GSM直接调制发射机的宽带压控振荡器

设计了一个应用于GSM850/EGSM900/DCS1800/PCS1900四频带直接调制锁相环发射机的宽带电感电容压控振荡器,采用温度计编码控制开关电容阵列,获得了宽频率覆盖范围,通过优化获得了良好的相位噪声性能.整个电路采用TSMC 0.18μm工艺实现,工作电压为3 V.仿真结果表明:压控振荡器的频率范围3 055～4 176 MHz(31%),调谐增益19 MHz/V变化至44MHz/V,相对最大调谐增益的变化值为56.8%,频偏20 MHz处相位噪声达到-155.7 dBc/Hz以下,最大功耗30 mW.