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1.
随着网络技术水平和网络需求的不断提高,单一的无线路由或有线网络不能满足需求。为了实现数据共享、资源共用就需要实现网络的整合和连接。笔者根据自己无线桥接知识的积累,再结合本单位实施的无线桥接技术实践对无线桥接的基本理论进行了详细概括,并对无线桥接和有线接入进行了对比。给无线桥接技术的理论研究和应用实践提供了指导和参考。  相似文献   

2.
皮佑国  黎永华  邓荣 《现代电子技术》2009,32(13):150-151,154
在对GSM蜂窝网络及其定位技术进行简要介绍的基础上,提出定位装置的功能需求,设计定位装置的系统方案,完成硬件设计和软件开发.开发的定位装置能够实现无线定位,并通过短信形式报告位置,对当前无线网络不做任何改动,已通过测试并投入使用,满足了移动对象的区域定位需求.  相似文献   

3.
《电子与电脑》2011,(7):71-71
ANADIGICS推出AWB7223小型蜂窝基站功率放大器(PA)。AWB72231是ANADIGICS无线基?站功率放大器产品组l合的新成员.该系列专门针对microcells、picocells和femtocells等小型蜂窝基站应用而优化。Mobile Experts最近发布的一项报告预测,到2014年,这类设备的发货量将从今年的260万件增长到2.000万件以上,  相似文献   

4.
王科 《通讯世界》2017,(5):67-68
移动互联网的快速发展,使得人们对于无线蜂窝通信网络的性能提出了更加严苛的要求.在这种情况下,微微蜂窝基站、毫微微蜂窝基站等小功率基站的出现,使得无线宏蜂窝网络逐渐转变为新兴的异构无线网络,不仅基站的密度有了很大的增加,网络结构也越发复杂,加上有限的频率资源,使得网络的抗干扰和越区切换问题受到了广泛关注,针对这两个问题,本文开展了相应的研究.  相似文献   

5.
PHS系统,是近年来发展迅速的无线通信系统之一。LCS无线定位业务作为PHS网络最重要的业务之一,对PHS系统的无线定位技术提出了要求。本文详细介绍了PHS基于微蜂窝网络的无线定位技术,并对PHS无线定位技术的发展进行了展望。  相似文献   

6.
崔高  戎蒙恬  刘涛 《信息技术》2011,(8):10-12,19
提出一种中继蜂窝网络中基于动态复用分割的无线资源分配方案。该方案在所设计的帧结构基础上,从时间域和频率域进行联合的资源分配。其基本思想是通过小区间的协作使频带资源可以最有效的复用来提高系统性能。仿真结果论证了该方案在小区容量方面可以获得较大的增益。  相似文献   

7.
随着网络技术水平和网络需求的不断提高,单一的无线路由或有线网络不能满足需求。为了实现数据共享、资源共用就需要实现网络的整合和连接。笔者根据自己无线桥接知识的积累,再结合本单位实施的无线桥接技术实践对无线桥接的基本理论进行了详细概括,并对无线桥接和有线接入进行了对比。给无线桥接技术的理论研究和应用实践提供了指导和参考。  相似文献   

8.
随着网络优化工作的深入开展和优化技术的提高,网络优化的范围在不断扩大。随着移动蜂窝无线网络规模的扩大,目前网络优化的重点已经转到室内及热点地方。本主要介绍的就是室内网络的优化及其方法。  相似文献   

9.
宋扬  张增一  石勇  邹臣国 《电声技术》2020,(3):60-60,96
搭载车地无线传输系统的列车能够将列车关键行车数据、列车故障数据及列车累计数据通过专用通道传输至控制中心的地面服务器,通过软件解析并提供WEB访问接口,使相关调度、维护、监控人员在访问终端上能够便捷、快速、随时获知列车行车状态.本文提出一种基于蜂窝移动网络的车地无线传输系统设计方案及在地铁列车上的应用.  相似文献   

10.
有些场景光纤传输部署困难、成本高、周期长,需研究使用无线传输将基站和核心网连通。首先介绍了无线回传的应用场景,详细论述和对比了实现无线回传的可行技术方案,分析了无线回传中头开销、MTU和时延的影响,为特定场景使用无线回传方案提供了参考。  相似文献   

11.
    
Yide Zhang  Lemin Li  Bo Li 《ETRI Journal》2006,28(6):799-802
Capacity has always been a major concern in wireless networks. This letter studies the impact of mobility on the overall system capacity in wireless cellular networks. In this letter, we present a simple system model which we developed to capture the inherent relationships among system capacity, new call blocking probability, handoff dropping probability, call terminating probability, and bandwidth utilization rate. We investigate the complex relationship between mobility and capacity‐related parameters. Through simulation, we demonstrate that mobility has a significant impact on capacity and is reversely proportional to the bandwidth reserved for handoff traffic.  相似文献   

12.
蜂窝网无线定位新技术   总被引:2,自引:0,他引:2  
张煦 《电信快报》1999,(3):3-5,24
首先说明移动电话用户紧急情况下需要无线定位业务。接着简述无线定位的几种常用技术,并分别说明时分多址和码分多址两类蜂窝网所用无线定位技术的情况。最后提到无线定位的误差来源。  相似文献   

13.
本文提出了一种基于无线传感器网络的应急通信系统的设计思路,可以有效的在恶劣条件下快速建立通信网络,为救援指挥及时提供所需的决策信息。阐述了系统的功能和组成,最后分析介绍了无线传感器网络的关键技术。  相似文献   

14.
尚杨  吴雪 《信息通信》2007,20(2):74-76
文章首先分别介绍了无线通信网络中的蜂窝网络及Ad Hoc网络的概念、发展及特点,分析了两者的不同及联系.之后又讨论了这两种网络中的信道分配问题:对于蜂窝网络介绍了基本的信道分配策略;对于Adhoc网络介绍了单频、双频和多频各自的频率分配特点.最后展望无线通信网络的发展方向和未来.  相似文献   

15.
    
Wireless communications have always faced the scarceness of bandwidth and until today the cellular division has solved this problem by making radio cells always smaller. However, as cell size is reduced, more users will probably require handoffs, and signaling can overload the system. Further, the decrease in cell dimension cannot ensure the best utilization of system resources, because user density in the cell is not constant over the time. Dynamic allocation might be the solution, but it is a complex task, basically due to complexity of the models for the mobility prediction, especially in those environments where users move very fast (e.g. highways). This last one is a typical environment where high mobility of vehicles does not allow small cell sizes and thus system capacity is intrinsically bounded. In this paper, we deploy an analytical model for a cellular network operating in a high mobility environment. Such a model is capable of representing and forecasting wireless system evolution in terms of channel occupancy, starting from the current state of the mobile network and road traffic. This model has been defined by integrating a vehicular traffic model with a wireless cellular communication one. With such approach the dynamic behaviour of the most critical mobile terminals, those associated with vehicles, are described in a very precise and specific way with respect to mobility. Many results obtained with specific simulation tools and herein reported show the good behaviour of our proposal. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

16.
本文首先简述无线移动通信结合发展潮流 ,从模拟至数字 ,即将过渡至宽带和多媒体通信。为此 ,全国无线通信网将推广使用异步转移模式。接着 ,本文说明移动信息基础结构包含接入网和骨干网 ,而且无线基台处于接入网边缘 ,提供移动手机的无线接入。最后指出低轨道 /中轨道卫星族对全球个人通信将起重要作用。  相似文献   

17.
本讨论新世纪初期固定有线通信和无线移动通信两大类通信网的发展前景,首先说明固定有线通信的核心网向全光网络发展的动向,其次是说明无线移动通信由蜂窝网向宽带网发展的趋势。  相似文献   

18.
Dynamic Adaptive Routing for a Heterogeneous Wireless Network   总被引:2,自引:0,他引:2  
This paper presents an integrated architecture of a Heterogeneous Wireless Network (HWN) and a dynamic adaptive routing protocol (DARP) for a HWN. To allow mobile users versatile communication with anyone or any device at any place and anytime, HWN integrates cellular network with an ad hoc network (independent Basic Service Set) in wireless local area network (WLAN) and reserves advantages of sizable coverage in a cellular network and high data rate in deployable ad hoc network. It also enlarges the scope of communication for ad hoc network and improves the throughput for cellular network. Consequently, nodes in HWN can communicate with each other or access Internet ubiquitously. We also address the routing issues for HWN, because the routing protocol for HWN is different from those used in cellular network or ad hoc network. The dynamic adaptive routing protocol establishes a better path for the source to arrive at the destination across multiple hops or cellular network and provides appropriate QoS (quality of service) in HWN.Through simulation, we will demonstrate the merit of the HWN, proposed routing performance on HWN and overhead of control traffic. A performance analysis of the proposed protocol is depicted. The results of the analysis, and simulations, are presented and discussed.  相似文献   

19.
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.  相似文献   

20.
针对无线传感器网络容易受噪音干扰的问题,在以往的工作基础上提出了一种新的业务流预测算法CAWP(Cellular Annealing-based Wavelet Prediction)。该算法首先利用小波变换对业务流进行分解,并将其小波系数作为抗体群。同时,采用定义的元胞演化规则代替免疫克隆退火中的交叉和变异操作,以获得下一时刻最优的小波系数。最后,通过仿真实验对比分析了该算法与其他算法之间的性能状况,结果表明CAWP具有较好的适应性。  相似文献   

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