动环监控系统无线传输组网方案的选择研究

凭借智能手机和4G网络的普及,移动通讯行业得到了迅猛的发展,为了满足人们生活的高效化,通讯行业不断的扩大网络覆盖面积,增强通讯传输速度,无线通讯的基站覆盖率不断提升,动环监控系统所能采用的传输资源环境也随之愈发复杂.动环监控系统在基站传输条件下缺少可以使用的固定链路,为了保证动环监控系统的正常有序工作,无线传输组网成为了必然选择,本文将在明确了动环监控系统组网的基本原理后,分析其短信组网、GPRS组网以及短信+GPRS混合组网的基本方案,探讨无线传输方案对动环监控系统的基本影响和发展方向.     

基于无线GPRS/SMS方式的移动基站动力环境监控系统

基于无线GPRS/SMS方式的移动基站动环监控系统,利用GSM短信和GPRS无线数据作为传输平台,实现对移动基站机房的动力环境信息的远程遥测、遥控、遥调和遥信,是基站动环监控的有效解决方案,特别是对边际基站、室内覆盖基站的监控,克服了有线方式下投资大、建设周期长的不足,实现了投资效益最大化。     

基于短信和GPRS／CDMA-1X的基站动力环境远程监控系统

基于短信和GPRS／CDMA-1X的基站动力环境远程监控系统,充分利用了公共移动网络,克服了传统方式数据非实时性、通信性能差、组网不灵活、设备成本高等缺点。系统采用分层结构设计,借助短信和GPRS／CDMA-1X无线数据网络作为传输平台,并结合GIS技术,实现了对基站工作环境的实时、连续、无人值守监控,提高了基站维护的效率。     

基于短信和GPRS／CDMA-1X的基站动力环境远程监控系统

基于短信和GPRS/CDMA-1X的基站动力环境远程监控系统,充分利用了公共移动网络,克服了传统方式数据非实时性、通信性能差、组网不灵活、设备成本高等缺点.系统采用分层结构设计,借助短信和GPRS/CDMA1X无线数据网络作为传输平台,并结合GIS技术,实现了对基站工作环境的实时、连续、无人值守监控,提高了基站维护的效率.     

基于PTN传输的基站动环监控的研究

当前以SDH/MSTP技术为基础的基站传送网已经满足不了3G、4G业务的发展需求,传输网络IP化将是电信业界的发展趋势,因此基于分组交换内核的传送技术PTN有望成为替代SDH的下一代主流技术.文章通过对基站动环监控PTN传输的组网方案、监控设备选型、组网成本、应用测试等几方面的研究,论述了基于PTN传输的基站动环监控的可行性、可靠性和先进性.     

存量基站动环监控单元改造技术方案

通过对三家电信企业交割给中国铁塔存量基站的动环监控系统现状出发,结合中国铁塔制定的基站动环监控系统全国一级架构、数据底端解析、无线信号传输等策略,制定145万个存量基站动环监控单元(FSU)的改造方案,并在中国铁塔动环监控建设当中顺利落地实施,实现国有资产的保值增值.     

多串口转GPRS组网方式的基站监控应用

在无有线传输资源的移动基站中,基站内智能设备通过多串口转GPRS传输方式实现了对基站的远程监控,提高了监控覆盖率。GPRS技术使用方便,成本较低,可以稳定地传送数据,有利于大规模网络的建立。     

TD-LTE基站动环智能监控系统设计方案

通过对中国移动现有动环监控系统的功能实现及组网特点进行分析,结合运营商的视频监控增值业务平台及4G基站IP化接入,提出实现TD-LTE基站动环监控、视频监控、门禁安防等功能的智能监控系统设计方案,并对以后的基站动环监控系统建设提出展望。     

基于MC55的GPRS移动基站告警图像监控系统的研究

基于MC55的GPRS移动基站告警图像监控系统是DSP系统与无线网络在基站监控领域的应用,通过对现代无线远程通信方式的研究,成功设计了应用现有移动无线GPRS网络的数据传输业务将无人值守基站告警图片上传到监控中心的方案。在硬件体系上主要采用DSP处理平台,基站底端图像采集采用DSP芯片,利用DSP高速AD进行视频信号采集,并在内部进行JPEG(数据)压缩,通过AT指令控制MC55模块进行无线数据通信,实现基站图片信号的采集和传输。     

基于多点协作联合传输的超密集组网性能分析

超密集组网的基站高密度特性会带来严重的小区间干扰,多点协作联合传输应用于超密集组网进行干扰管理是目前的研究热点,该文对多点协作联合传输时基站密度对网络性能的影响进行了分析。首先采用随机几何方法推导了3维空间基站与用户距离的概率密度函数,为选取距离用户最近的多个基站联合传输的协作机制提供了基础;然后结合有界双斜率路径损耗模型,进行用户下行链路的干扰建模,进一步推导出用户下行链路覆盖率和网络区域频谱效率的表达式,并分析了协作基站数、基站密度等参数对网络性能的影响。数值仿真表明:协作基站数为2时就可使下行链路覆盖率增加10%,且实现2到3倍的频谱效率的增益,当协作基站数为3时,费效比更优,同时可得到多点协作下的基站密度极限使区域频谱效率最高。该文工作可为下一代移动通信网络的基站部署提供理论支持。     

应用于无线传感器网络的语音传输系统的设计与实现

随着宽带网络和信息技术的日益普及、企业信息化需求的进一步提高,回话网络、Internet以及移动网络三网分离的局面已不能满足企业办公需要,因此需要一种整合多种通信方式,对统一消息数据进行综合管理的企业融合通信技术。另一方面,随着短距离无线通信技术的成熟与发展,短距离无线通信技术同样需要融入固话网络、Internet以及移动网络。本文在分析无线传感器网络技术的基础上,提出了一种新型的VoIP接入网关的设计方案,给出了一种使用IP网络电话的方式;对VoIP接入网关的硬件设计及系统结构做了详细的分析;对VoIP接入网关的整体硬件进行了详细的设计并给出PCB设计实物。     

Analysis of UAV wireless network coverage and handover performance

For the characteristics of unmanned aerial vehicle (UAV),such as high mobility,adjustable height,and high probability of line-of-sight channels,which introduced multiple challenges to the design and deployment of current and future wireless network,and the networking performance of UAV was the focus and difficult issues in the industry,the network coverage and handoff performance of heterogeneous UAV wireless network was analyzed,which provided insights into UAV wireless networking.Specifically,considering the outdated channel state information introduced by the UAV’s mobility,analytical expressions of handover probability,handover error probability,and coverage probability for heterogeneous UAV wireless network were derived by utilizing the tools from stochastic geometry.In addition,the impacts of the UAV’s mobility,height,as well as the density of terrestrial base stations on the aforementioned performance metrics were investigated.It shows that the outdated channel state information caused handover error,which increases first and then decreases with the increase of UAV’s moving speed and density of base stations.Meanwhile,the impact of UAV’s flight height on coverage probability is more significant than that of moving speed.     

无线Mesh网网络层和MAC层相关研究

随着无线网络技术的发展,无线mesh网凭借其多跳通信能力为拓宽WiFi网络的覆盖率提供了有效的途径。利用低发射功率来提高覆盖率和容量的能力,使其在普遍存在的宽带接入中扮演重要角色。凭借其独特的优势,WMN发展非常迅速,并广泛应用于众多领域。为了更好的说明WMN领域存在的挑战,详细描述了无线mesh网的MAC层和网络层研究状况,并且提出了可能提高多跳网络吞吐量的新协议。     

Cross-Layer Design for QoS Support in Multihop Wireless Networks

Due to such features as low cost, ease of deployment, increased coverage, and enhanced capacity, multihop wireless networks such as ad hoc networks, mesh networks, and sensor networks that form the network in a self-organized manner without relying on fixed infrastructure is touted as the new frontier of wireless networking. Providing efficient quality of service (QoS) support is essential for such networks, as they need to deliver real-time services like video, audio, and voice over IP besides the traditional data service. Various solutions have been proposed to provide soft QoS over multihop wireless networks from different layers in the network protocol stack. However, the layered concept was primarily created for wired networks, and multihop wireless networks oppose strict layered design because of their dynamic nature, infrastructureless architecture, and time-varying unstable links and topology. The concept of cross-layer design is based on architecture where different layers can exchange information in order to improve the overall network performance. Promising results achieved by cross-layer optimizations initiated significant research activity in this area. This paper aims to review the present study on the cross-layer paradigm for QoS support in multihop wireless networks. Several examples of evolutionary and revolutionary cross-layer approaches are presented in detail. Realizing the new trends for wireless networking, such as cooperative communication and networking, opportunistic transmission, real system performance evaluation, etc., several open issues related to cross-layer design for QoS support over multihop wireless networks are also discussed in the paper.     

无线通信系统异构网络的自动邻区关联方法

主要提出一种宏小区与毫微微小区混合组网的异构无线通信网络,从而设计了一种用于异构无线通信网络中的基站间自动邻区关联的方法,并阐述了具体实施步骤。该方法支持异构网络中的基站自组织功能,基站能够在自动邻区关联的过程中正确地获得邻区基站的ID,从而成功构造邻区关系且无需人工配置,克服了已有方法存在的缺陷。同时,该方法无需修改空口信令,也不会增加空口信令开销。     

行星表面有人探索高速无线网络体系架构及关键技术

针对行星表面有人探索任务对高速无线通信的需求，提出了一种基于异构组网思想的网络体系架构，并对关键技术进行了分析和设计。该架构采用“三网两体制”的设计思路，将整个网络分为高速传输网、多媒体接入网、覆盖扩展网三个组成部分，三层网络分别完成高速骨干传输、多节点多业务接入、覆盖范围灵活改变的功能。根据三个网络不同的节点处理能力和传输需要，设计了高速传输体制、灵活接入体制两种传输体制，及基于无线多跳的覆盖扩展技术、多子网通信切换技术、多体制融合技术等关键技术。该网络架构具有裁剪灵活、协议开销小、支持业务类型多等特点。     

基于数据链的空中平台越区切换方法研究

本文结合数据链技术和组网方式的特点,根据现有的技术体制,全面考虑了战场环境,综合通信基站的通信覆盖范围和与作战飞机之间的通信质量等信息,提出了一种越区切换的实现方法。     

Throughput-range tradeoff of wireless mesh backhaul networks

Wireless backhaul communication is expected to play a significant role in providing the necessary backhaul resources for future high-rate wireless networks. Mesh networking, in which information is routed from source to destination over multiple wireless links, has potential advantages over traditional single-hop networking, especially for backhaul communication. We develop a linear programming framework for determining optimum routing and scheduling of flows that maximizes throughput in a wireless mesh network and accounts for the effect of interference and variable-rate transmission. We then apply this framework to examine the throughput and range capabilities for providing wireless backhaul to a hexagonal grid of base stations, for both single-hop and multihop transmissions for various network scenarios. We then discuss the application of mesh networking for load balancing of wired backhaul traffic under unequal access traffic conditions. Numerical results show a significant benefit for mesh networking under unbalanced loading.     

采用多向散射通信进行可变中心组网研究

无线通信中的可变中心组网研究是一个具有创新性和需求迫切性的研究课题。可变中心组网是指在通信时,通信中心可根据具体情况进行变换,这样比固定通信中心的通信网络具有更大的灵活性和抗毁性。就采用多向散射通信方式进行可变中心组网的网络结构及特点进行了探讨和研究,提出了几种可行的无线、超视距及可变中心组网方案。     

Overlapping coverage with reuse partitioning in cellularcommunication systems

In cellular communication systems overlapping coverage areas of nearby base stations provide some users with access to more than one base. This can be used to improve teletraffic performance. Mobile users who are distant from base stations are helped most by this because they are more likely to be in communication range of other nearby bases. Reuse partitioning, on the other hand, tends to be most helpful to users that are close to base stations, because they can use channels from more partitions. This paper considers the combined use of overlapping coverage and reuse partitioning so that all users gain some advantage. We develop an analytical model for such systems. Theoretical traffic performance characteristics are obtained and compared with those for fixed channel assignment schemes. Priority for handoff calls is considered. Simulation results validate the analysis