浅谈无线接入技术

无线接入技术可分为模拟无一接入技术和数字无线接入技术,数字无线接入系统又有多种解决方案,包括数字直接扩频技术、ＧＳＭ、ＣＤＭＡ、ＤＥＣＴ、ＰＨＳ和ＳＣＤＭＡ等。     

几种宽带接入技术比较及其应用分析

文章介绍了ADSL、以太网、光纤、无线和Cable Modem等当前主流宽带接入技术，分析了每种技术的特点和具体应用场合，最后对宽带接入技术发展进行了展望。     

有线电视网络的发展现状与趋势

双向化改造后的有线电视网络,既是广播电视信号的传输网络,也是宽带业务的承载网络,是有线电视运营商实现业务发展与转型的基础网络.其中有线接入网络是有线电视网络发展的关键,与用户带宽需求和有线接入技术的发展密切相关.通过调研当前国内外有线电视网络的发展现状、有线接入技术及标准的研究进展,分析了有线接入网络的发展趋势,最后对一种自主创新的吉比特同轴接入技术(HINOC)进行了介绍.     

VSAT的技术进展

本文从传输技术、多址接入方式、网络管理和网络体系结构等方面综述了甚小口径卫星地球站在技术上的最新进展。     

接入网光缆工程施工新技术

介绍了当前在接入网光缆工程中出现的各种新的施工技术,如气吹微缆技术、路面微槽光缆敷设技术、排水管道光缆敷设技术,并讨论了这些新技术相关的施工方法、特点。与常规的管道、架空敷设方式相比,这些新的施工技术能灵活地适应接入网的工程环境,具有施工周期短、效率高,光纤容量大,易于扩容等特点,相信在将来的接入网光缆工程中会得到越来越广泛的应用。     

HFC上行信道的通信容量与多址接入方案的比较

HFC上行通信是构建宽带HFC接入网的关键。本文将SCDMA多址接入方案引入HFC通信系统中,在对HFC信道分析的基础上,通过建立Simulink仿真模型比较了SCDMA与TDMA的性能。     

平等接入在住宅区光纤到户工程中的建设探讨

本文结合光纤到户国家标准,对住宅区光纤到户的分工界面、网络系统组网、上联设计、设备间与电信间的选择、光缆入户设计、光分光器部署、工程维护等内容进行了阐述,对住宅区光纤到户如何实现平等接入,保障用户自由选择的权利等关键内容进行了详细描述和探讨。     

接入光缆网在综合业务接入区中的建设应用研究

接入光缆网在5G规模部署下向着固移融合、综合承载的目标架构不断演进.本文通过对于综合业务接入区中光缆网架构的应用研究,详细阐述主干与配线光节点、主干与配线光缆的部署方案,为综合业务接入区中光缆网的规划与建设提供明确的指导意见.通过现有光缆网络在几种场景下的优化以及新技术、新产品在5G前传网络中的应用,从两方面对光缆网络...     

农村地区接入网建设建议

本文根据近年来我国农村地区通信发展的态势,在一线调研的基础上,主要从农村地区接入网建设的角度出发,分析农村地区接入网发展的现状及存在的问题,从市场、技术、运维等角度提出今后农村地区接入网的发展策略,并提出一系列有争议的技术的取向及具体的网络建设原则和建议.     

Smart cards and handheld terminals as applied to field communications

Portable data carriers such as smart cards (Integrated Chip Cards) and handheld terminals allow for the gathering and distribution of information in remote and rural areas where traditional telecommunications systems do not exist. The portable units allow for connection to networks at convenient hubs through a variety of technologies including radio frequency (RF), cellular radio, and very small aperture terminal (VSAT). Applications such as agricultural data access, weather data access, and health care data can be addressed using the portable data carrier as an extension of the network.     

浅谈VSAT系统数据网多址协议

卫星数据网多址协议(access protocol)是发展VSAT数据网的关键技术。依据VSAT数据网所承载的业务特点，ALOHA协议是其采用的重要多址技术，根据端站报文的入网方式，VSAT共享协议可分为固定分配、随机接入、预约三类。主要对这三类共事协议进行扼要的介绍。     

农村有线电视网络双向改造方法研究

通过分析农村有线电视网络和有线电视网络双向改造的技术现状,对有线电视双向网络的结构进行了剖析,对有线电视网络双向网改造的方式进行了比较和分析,最终提出了适用于广大农村现状的有线电视网络双向网改造方式。     

EoC系统在有线电视接入网双向改造中的应用

针对EoC系统在有线电视接入网双向改造中的应用进行分析,阐述EoC系统小区接入网改造中的系统方案,并对系统实现中所遇到的问题加以论述。     

接入网组网与光电缆设备施工标准要求

本文介绍了用户接入网的划分、种类、构成及特点,以及如何组网和光电缆工程施工的标准要求.     

运用接入新技术组建农村用户接入网

运用接入新技术且建农村用户接入网已势在必行。本文首先对接入网的基本概念和Ｖ类接口作了说明。继而对接入技术的发展动向作了介绍。最后对组建我国农村用户搪入网的有关策略进行了论述。     

SCDMA--一种创新的无线用户环路系统

介绍了ＳＣＤＭＡ系统的特点,它用在市话接入网中的优势,ＳＣＤＭＡ所使用的３种新技术——智能天线、同步ＣＤＭＡ、软件无线电技术。     

Crossing the digital divide: cost-effective broadband wireless access for rural and remote areas

The use of wireless, DSL, and cable for broadband access has become increasingly prevalent in metropolitan areas. While these technologies are being successfully utilized in terms of both service quality and economics in densely populated areas, there are still vast geographic regions where broadband services are either prohibitively expensive or simply unavailable at any price. The article examines several alternatives for using 2.4 GHz 802.11b (WiFi) technology to provide fixed broadband access in rural areas consisting of towns, smaller remote communities, clusters of subscribers separated by large intercluster distances, as well as widely scattered users. Our approach is to model a network based on realistic demographics, equipment and operations costs, service revenues, and customer demand and usage, and calculate the lifecycle economics in terms of capital investment and profitability. We consider the cost benefits of several emerging technologies and architectures, including high gain antennas, dynamically steerable beamforming antennas, and multihop routing. Our results show that cost-effective affordable high-speed wireless Internet access can be provided in rural and remote areas using nontraditional and innovative approaches, bridging the so-called digital divide.     

Simulation models for performance evaluation of satellite multipleaccess protocols

Simulation models are described for the performance evaluation of satellite multiple-access protocols used in VSAT (very small aperture terminal) data networks. Since the design of VSAT-based wide-area networks for interactive applications is critically dependent on the delay-throughput characteristics of the channel access protocol used, detailed simulation models have been developed to augment analytical performance-evaluation methods. Simulation models for several candidate VSAT access protocols, including random-access techniques such as Aloha, selective reject Aloha and slotted Aloha and demand-assignment multiple-access based techniques, are discussed in terms of traffic-source models, access algorithms, and performance-evaluation criteria. Numerical results for a realistic interactive data VSAT network environment are presented     

Investigation of capacity and call admission control schemes in TD‐SCDMA uplink systems employing smart antenna techniques

Due to the TDMA (time division multiple access)/time division duplex (TDD) specialization in the uplink (UL) of code division multiplex access (CDMA) systems, some advanced techniques, such as smart antenna (SA) and multi‐user detection (MUD), are utilized conveniently in time division‐synchronous code division multiplex access (TD‐SCDMA) systems. These advanced techniques have great impacts on the capacity and radio resource management (RRM) schemes. In this paper, the UL capacity and load models specified for TD‐SCDMA systems are proposed, in which the impacts from SA and MUD techniques are considered, and the UL load can be estimated based on the total received power in the base station. According to the proposed theoretical capacity and load evaluation models, the call admission control (CAC) strategies suitable for TD‐SCDMA systems are presented. Since there are two kinds of SA schemes (i.e., tracking beam antenna (TBA) and switched beam antenna (SBA)) utilized in TD‐SCDMA systems, the efficient CAC algorithms suitable for these two SA schemes are designed and evaluated, which are based on principles of the interference increase estimation. All simulation results show that the proposed CAC strategies can work efficiently and improve performances of TD‐SCDMA systems dramatically. Copyright © 2009 John Wiley & Sons, Ltd.     

卫星互联网下的VSAT卫星通信

本文介绍了VSAT通信在卫星互联网下的新发展,分析了VSAT系统的互联网接入方式,研究了卫星互联网的技术热点,展望了卫星互联网的发展前景.