长距离EPON关键技术的研究

在以太无源光网络(EPON)系统中,协议规定了最长传输距离不超过20km。但是在某些应用中,光纤线路的距离需要到达几十千米。文章探讨了长距离EPON的实现方法:通过对EPON系统的物理层和多点媒体访问控制(MPMC)子层的部分修改可以实现所需的传输距离。     

一种延长EPON传输距离的方法

在以太无源光网络（EPON）系统中,光线路终端（OLT）和光网络单元（ONU）之间的最长光纤传输距离为20 km,但在一些较偏远地方,有些镇站距中心机房的距离往往大于20 km,提出一种延长EPON系统传输距离的方法,它在OLT上行采用光纤收发器,实现了大于20 km的EPON传输。     

一种延长EPON传输距离的方法

在以太无源光网络(EPON)系统中,光线路终端(OLT)和光网络单元(ONU)之间的最长光纤传输距离为20km,但在某些光纤到村(FTTV)之类的应用中,光纤线路的距离达到了80km甚至更远.文章提出了一种延长EPON系统传输距离的方法,它实现了一种适用于EPON系统的光功率放大器,且对EPON的注册发现窗口,上行带宽分配周期等参数进行了调整.     

EPON专用芯片设计

文章介绍了集成化设计以太网无源光网络(EPON)产品中传输汇聚(TC)子层芯片的结构设计框图,详细介绍了光线路终端(OLT)和光网络单元(ONU)的TC子层芯片设计.在此结构框架下,对EPON系统性能进行了仿真,发现在相同业务负载的情况下,EPON系统业务延迟小于以ATM为基础的无源光网络(ATM PON)系统中的相应延迟.     

多业务长距离电力EPON系统的设计与应用

结合益阳电业局县级通信系统建设需求,合作开发了支持多业务长距离传输的电力EPON系统,集成多种业务接口,满足电力系统二次安全防护的技术要求,在1:16分支比的情况下,最大传输距离为54km.文章重点描述了电力EPON系统的技术特点及设计方案.该系统已经在益阳电业局的南县电力局试运行,目前系统运行稳定.     

基于EPON技术下的宽带接入网应用初探

近几年,宽带接入技术突飞猛进,特别是光纤接入技术（FTTX）采用光纤作为传输介质,具有传输量大、传输质量高、高可靠性、传输距离长等优点。目前EPON是FTTX的主流实现方式,能够通过单一光网络平台实现数据、语音和视频业务。     

EPON中测距技术的研究

以太网无源光网络(EPON)将千兆以太网与无源光纤接入的优势相结合,实现低成本、高速、远距离接入.EPON中光分路器/耦合器(Splitter/Couple)与每个光网络单元的距离各不相同,传输延时也不同,来自不同ONU的数据帧可能在OLT处出现碰撞冲突.为实现EPON系统上行TDMA接入,用OPNET创建了一个光网络...     

SNMP和OAM在EPON网元管理系统中的研究与实现

提出了一种EPON网元管理系统的设计方法,该方法充分考虑了OAM和SNMP协议各自的特点,并将OAM和SNMP结合起来实现了对汇源开发的EPON系统的管理.本文详细介绍了SNMP Agent基于linux的实现,并描述了EPON系统OAM子层的功能、特点.     

EPON中测距技术的研究

以太网无源光网络（EPON）将千兆以太网与无源光纤接入的优势相结合,实现低成本、高速、远距离接入。EPON中光分路器耦合器（Splitter／Couple）与每个光网络单元的距离各不相同,传输延时也不同,来自不同ONU的数据帧可能在OLT处出现碰撞冲突。为实现EPON系统上行TDMA接入,用OPNET创建了一个光网络节...     

EPON接入技术在海底观测网络中的应用

EPON接入是一种应用于光网络的新型的宽带接入技术。分析了EPON技术以其传输速率高、损耗低、兼容性强等优势应用于海底观测通信网络中的可行性,利用OptiSystem仿真软件搭建了EPON光传输链路的仿真模型,并对1.25Gb/s上下行信号的传输性能及Q因子、误码率、眼图等参数进行分析,进而验证了EPON系统较高的传输性能。     

Technology for extending transmission distance of EPON system

At present, the maximal transmission distance between the optical line terminal (OLT) and opticalnetwork unit (ONU) of an Ethemet passive optical network (EPON) system is 20 km.However, this distance should be extended to 50 km or even longer in some applications such as fiber to the village (FTTV).A method for extending the transmission distance of an EPON system is proposed in this paper, in which the optical power amplifier and the adjustment of dynamic bandwidth allocation (DBA) are the key technologies.     

A study of quality of service in the universal DBA algorithm using a PIC-based EPON testbed

Ethernet Passive Optical Network (EPON) has emerged as a promising technology since it offers high bandwidth at a distance that can go up to 20 km. In the upstream EPON transmission, a dynamic bandwidth allocation (DBA) algorithm is needed to avoid collisions and to efficiently allocate the bandwidth. This paper proposes an algorithm called as a Universal DBA (UDBA) algorithm that can support the priority universally in the entire EPON system. A peripheral interface controller (PIC)-based EPON testbed is used to test the algorithm within the mulipoint control protocol environment. For the performance study, we have compared the results achieved using UDBA in terms of delay, throughput, and fairness with two other DBA algorithms. UDBA shows improvements in terms of expedited forwarding, assured forwarding and best effort delay as much as 43.9, 42.6, 20 % over User-oriented Hierarchical Bandwidth Scheduling with Single Cycle (UHSA-S) and 37.5, 20.2, 25.3 % over Modified Smallest Available Report First (MSARF), respectively. Throughput is improved as high as 17.9 % over UHSA-S and 12.8 % over MSARF. In addition, the fairness index of UDBA is higher up to 14 % as compared to UHSA-S and 2.7 % as compared to MSARF.     

QoS Control Schemes for Two-Stage Ethernet Passive Optical Access Networks

Ethernet passive optical networks (EPONs) have emerged as the one of the most promising candidates for next-generation access networks. These new architectures couple low-cost optics with advanced edge electronics to offer vastly improved scalability over competing digital subscriber line and cable modem offerings. This paper proposes several novel architectural enhancements for EPON, which will help increase the viability of optical access over a broader range of subscriber access scenarios. Specifically, this paper proposes a two-stage EPON architecture that allows more end-users to share an optical line terminal link, and enables longer access reach/distances (beyond the usual 25 km distance). In addition, a new dynamic bandwidth allocation (DBA) algorithm is proposed to effectively allocate bandwidths between end users. This DBA algorithm can support differentiated services in a network with heterogeneous traffic. We conduct detailed simulation experiments to study the performance and validate the effectiveness of the proposed architecture and algorithms.     

10G EPON最新进展及在三网融合中的应用

随着三网融合的具体实施,用户对带宽的需求不断提升,10 G EPON作为下一代宽带接入技术备受关注。10 G EPON具备高带宽、大分光比、长距离的特点,满足＂三网融合＂后以视频业务为主的高带宽发展需求,满足FTTH、FTTB、FTTO、FTTN各种高带宽需求的应用场景,从10 G EPON的进展情况、10 G EPON的关键技术及其实际应用等几个方面进行了分析。     

宽带以太网PON(EPON)技术介绍

阐述了EPON技术中媒体接入控制MAC以及OLT和ONT之间的通信过程和技术规范,介绍前向纠错技术FEC在EPON中的应用实践,延长了EPON的传输距离和增加最大分路比,同时根据各地的用户及分布情况、投资收益分析比数据、网络生命周期成本等,合理选择双向网络改造技术方案。