最新刊期
      卷 ， 期 5 ， 2006
      • Lü Jianxin
        Issue 5, Pages: 1-4(2006) DOI: 10.13756/j.gtxyj.2006.05.001
        摘要：With the rapidly growing need of information transmission,40 Gbit/s optical transmission becomes the natural choice for the next generation communication networks.This paper describes the principle and structure of 40 Gbit/s（STM-256） SDH transmission equipment,analyzes the key technologies for their manufacture and presents the latest research results achieved by FiberHome Telecommunication Technologies Co.,Ltd..  
        关键词：40 Gbit/s;SDH;STM-256 framer;cross connection   
        2
        |
        106
        |
        3
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514549 false
        发布时间：
      • Issue 5, Pages: 4(2006)
          
        2
        |
        23
        |
        0
        <HTML>
        <Meta-XML>
        <引用本文> <批量引用> 27514380 false
        发布时间：
      • Liu Guohui,Mao Qian
        Issue 5, Pages: 5-8(2006) DOI: 10.13756/j.gtxyj.2006.05.002
        摘要：In recent years,a rapid growth of data services has been seen in China.This article analyzes the trend of SDH evolution in IP-based information networks and predicts that SDH will continue to play a main role in transmission networks for fairly long period of time and the transmission network technology will gradually evolve towards the co-existence of packet transmission technology with SDH technology in the long term.Then it studies the influence of this trend on the SDH network structure and finally gives out the strategy and steps of the evolution of SDH ring net to mesh net.  
        关键词：SDH;MSTP;IP-based;network evolution   
        3
        |
        80
        |
        2
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514608 false
        发布时间：
      • Xu Yunbin
        Issue 5, Pages: 9-10(2006) DOI: 10.13756/j.gtxyj.2006.05.003
        摘要：Object models for control plane components,such as CallC,CC,RC,LRM,have been proposed in ITU-T G.7718,but no appropriate object model for control network element management has been given.With reference to the domain definition in Section（7.3） of ITU-T G.7718,a new control network element object for control plane management is introduced in this paper.  
        关键词：ASON;control network element;object model   
        2
        |
        53
        |
        2
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514428 false
        发布时间：
      • Liu Yuan,Zhang Pei,Gu Wanyi
        Issue 5, Pages: 11-12(2006) DOI: 10.13756/j.gtxyj.2006.05.004
        摘要：With the rapid commercial applications of the WDM technology and the explosive growth of the transmission bandwidth of backbone networks,network survivability has become increasingly more important.The traditional network survivability includes protection and restoration mechanisms and the latter has direct effects on the reliability of the traffics on the failure of networks.Based on the research results in this field,we present three different restoration algorithms from three angles and analyze their performances in terms of restoration probability and resource utilization through simulation data.  
        关键词：WDM;network survivability;restoration mechanism   
        2
        |
        92
        |
        2
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514477 false
        发布时间：
      • Liu Fue,Bu Shi,Ge Ning,Zhou Zucheng
        Issue 5, Pages: 13-15(2006) DOI: 10.13756/j.gtxyj.2006.05.005
        摘要：Making the bandwidth distribution in Metropolitan Area Transport Network more flexible and stable,Link Capacity Adjustment Scheme（LCAS） is a function that the new generation Multi-Service Transport Platform（MSTP） products must have.In this paper,the simulation of LCAS based on imbedded processors combined with FPGA is presented and a number of technical problems in the simulation by finite state machines explored.  
        关键词：LCAS;embedded processor;state machine;random vector   
        2
        |
        46
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514384 false
        发布时间：
      • Zhong Shan~1,Yue Xiang~2
        Issue 5, Pages: 16-18(2006) DOI: 10.13756/j.gtxyj.2006.05.006
        摘要：It is often necessary to fairly allocate bandwidth among services with different requirements in high-speed packet switching circuits while meeting their QoS parameters.When queues of such services are multiplexed to a single output link,a variety of traffic scheduling algorithms are used for this purpose.Weighted Fair Queuing（WFQ） is a commonly used scheduling algorithm,which can not only ensure fairness,but also provide good delay performance.This paper discusses the basic principle of WFQ in detail.  
        关键词：traffic scheduling;WFQ;GPS;PGPS   
        2
        |
        755
        |
        6
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514456 false
        发布时间：
      • Song Wei,Yuan Xinchang,Hu Bo
        Issue 5, Pages: 19-21(2006) DOI: 10.13756/j.gtxyj.2006.05.007
        摘要：To surmount the disadvantages of the existing media server processing in respect of cost and capacity,a HMP-media-server-based media processing method is advanced.Part of the low-side services,e.g.non-mixed voice services,in IP multimedia communications can be processed by single-channel non-real-time code conversion when CPU is not very busy to exchange the capacity of memory recourses for the CPU capability and take off a large amount of workload from the latter and leave it more resources to accommodate high-side or burst services,resulting in a more rational distribution of resources of the entire system and the improvement of processing efficiency and service quality.  
        关键词：media server;softswitch;HMP;voice code conversion   
        2
        |
        34
        |
        3
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514417 false
        发布时间：
      • Huang Ying~1,Zhu Mucheng~2,Li Hui~1
        Issue 5, Pages: 22-24(2006) DOI: 10.13756/j.gtxyj.2006.05.008
        摘要：At present,it has important practical significance to implement the interworking between four kinds of key protocols in softswitch technology for NGN,namely H.323,SIP,MGCP and Megaco（H.248）.On the basis of a brief description of these protocols,this paper presents the solution for the interworking,shows the mappings between parts of the main protocols in line with the variance of the call states and explains the implementation method by practical examples.  
        关键词：softswitch;H.323;SIP;MGCP;H.248;interworking;protocol mapping   
        2
        |
        105
        |
        9
        <HTML>
        <Meta-XML>
        <引用本文> <批量引用> 27514580 false
        发布时间：
      • Wang Chengyi
        Issue 5, Pages: 25-28(2006) DOI: 10.13756/j.gtxyj.2006.05.009
        摘要：On the basis of the analysis of the protection mechanisms for conventional data networks and the line protection mechanism for transport networks,this thesis systematically describes the protection mechanism for Ethernet network services in the Metro Ethernet Network（MEN）,especially its protection reference model and four basic protection mechanisms.Through the typical application scenarios of the protection mechanism for MEN and in connection with the interoperations between the layers of the layered network,it makes a comprehensive analysis of the protections between the layers.  
        关键词：MEN;protection mechanism;protection reference model;layered protection   
        2
        |
        31
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514541 false
        发布时间：
      • Issue 5, Pages: 28(2006)
          
        2
        |
        17
        |
        0
        <HTML>
        <Meta-XML>
        <引用本文> <批量引用> 27514378 false
        发布时间：
      • Li Hanbing~1,Mao Qian~1,Chen Feng~2
        Issue 5, Pages: 29-31(2006) DOI: 10.13756/j.gtxyj.2006.05.010
        摘要：The concepts of P2P（Peer-to-Peer） and FTTH are briefly described in this paper,focusing on the analysis of P2P applications, their required bandwidths and the application features in IPTV systems.A conclusion is arrived at that both the applications of P2P and the popularization of FTTH are inevitable.  
        关键词：P2P application;IPTV;FTTH;bandwidth requirement   
        2
        |
        70
        |
        2
        <HTML>
        <Meta-XML>
        <引用本文> <批量引用> 27514466 false
        发布时间：
      • Huang Lin,Hu Bichun,Liu Wu
        Issue 5, Pages: 32-34(2006) DOI: 10.13756/j.gtxyj.2006.05.011
        摘要：The Ethernet Passive Optical Network（EPON）has become one of the most effective ways of communication for broadband access,for which it is especially important to provide a stable and highly-efficient control software system.This paper gives a brief introduction to the EPON architecture and the basic requirements of its software system.and presents a relevant description of the open source routing suite Quagga that provides TCP/IP routing service.As Quagga naturally satisfies the requirements of the EPON software system and provides the basic functions that its needs,the paper discusses the implementation of the overall software design scheme by reference to the Quagga architecture.  
        关键词：EPON;open source routing suite;CLI;SNMP   
        2
        |
        139
        |
        6
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514594 false
        发布时间：
      • Sui Qing,Li Guangcheng,Tian Guangli
        Issue 5, Pages: 35-37(2006) DOI: 10.13756/j.gtxyj.2006.05.012
        摘要：Breaking through the limitations of the conventional point-to-point solutions,PON technology has been regarded as having the best perspective among all optical access network technologies.Due to the complex application environment of optical access networks,there are many kinds of applicable PON access technologies,among which EPON（Ethernet PON） and GPON（Gigabit PON） are most typical at the present.This paper presents an EPON-and-GPON-converged access solution in line with the requirements of actual FTTH projects.  
        关键词：EPON;GPON;FTTH   
        2
        |
        143
        |
        8
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514407 false
        发布时间：
      • Liu Wu,Hu Baomin,Liu Deming,Lu Xi
        Issue 5, Pages: 38-40(2006) DOI: 10.13756/j.gtxyj.2006.05.013
        摘要：Dynamic Bandwidth Allocation（DBA） is crucial in EPON systems.In this paper,a fairness-guaranteed scheme is introduced for DBA in EPON,which is of moderate computational complexity and guarantees both the efficiency and fairness of DBA.The optimum algorithm is given through deduction and the simulation results from using synthetic traffic confirm its good performance against the existing bandwidth allocation schemes.  
        关键词：Ethernet PON（EPON）;Dynamic Bandwidth Allocation（DBA）;Quality of Service（QoS）;self-similarity.   
        2
        |
        125
        |
        1
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514490 false
        发布时间：
      • Zhang Pengcheng,Su Li,Jin Depeng,Zeng Lieguang
        Issue 5, Pages: 41-44(2006) DOI: 10.13756/j.gtxyj.2006.05.014
        摘要：Circuit emulation provides a seamless migration approach to backbone PSNs without interruption of legacy services.In this paper,the design of a specific chip for circuit emulation based on IP is put forward and realized and the main functional modules and the key algorithms including an all-digital adaptive clock recovery method and a dynamic depth buffer algorithm are described in detail.The design has been verified and tested in actual networks.  
        关键词：circuit emulation;clock recovery;dynamic depth buffering   
        4
        |
        43
        |
        2
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514396 false
        发布时间：
      • Li Qi,Wang Yuqiang,Li Hui
        Issue 5, Pages: 45-47(2006) DOI: 10.13756/j.gtxyj.2006.05.015
        摘要：In recent years,along with super-speed developments of our country telecommunication network,the scale of the network is from strength to strength,the structure is also gradually complicated.How to increase the operational level of the telecommunication network everywhere,how to complete the communication guarantee responsibility given from the superior,how to keep the high level service quality,how to manage the equipments of the different manufactory in unification,have become to the problem that people pay attention to be resolved urgently.The article is going to introduce the solution that aims at the problem,and set forth the design principle,the adoption technique,the module of function,the developments object in detail.  
        关键词：emergency communication;GIS;network resource management;establish   
        2
        |
        175
        |
        6
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514435 false
        发布时间：
      • Liu Jiaoyu,Zhang Guangfu
        Issue 5, Pages: 48-50(2006) DOI: 10.13756/j.gtxyj.2006.05.016
        摘要：The design and realization of an ARM-based embedded Ethernet access scheme is introduced,the hardware and software for the scheme expatiated on and the remote data transmission and monitoring by the microprocessors through the Ethernet realized.In this project,the characteristics of the embedded system with applications as the center and computer technology as the basis and of software/hardware clipping are fully revealed.Ethernet also has superiorities in its applications in the industrial control field.Embedded internet termination brings about a good combination of the embedded control systems and equipment.  
        关键词：Ethernet;TCP/IP;embedded system   
        2
        |
        332
        |
        23
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514502 false
        发布时间：
      • Zou Qingyan
        Issue 5, Pages: 51-53(2006) DOI: 10.13756/j.gtxyj.2006.05.017
        摘要：Along with the rapidly increasing number of Internet users,we have seen a continuously growing need for access network bandwidth.GEPON（Gigabit Ethernet Passive Optical Network） technology has become an "upstart" for access networks.It is an integrated access solution incorporating high-rate data,video and voice services.Making use of FTTH/FTTB/FTTC（Fiber to the Home/Building/Curb）,it can provide the residential and business subscribers with the highest bandwidth of up to 1 Gbit/s.Characteristic of economical cost of construction,convenient access,easy maintenance and simple network architecture,it has received support and approval from more and more telecom operators and manufacturers.This paper describes the solution of district GEPON by Shenzhen Netcom.  
        关键词：district GEPON;service;solution   
        2
        |
        55
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514511 false
        发布时间：
      • Deng Liqiong,Xu Wencheng,Chen Weicheng,Wang Xude,Liu Songhao
        Issue 5, Pages: 54-57(2006) DOI: 10.13756/j.gtxyj.2006.05.018
        摘要：The performances of different types of fibers used in current CWDM systems are compared and their advantages and disadvantages evaluated on the basis of the experimental data from the system tests.The reliability of the applications of both standard SMF and NZ-DSF in CWDM systems is confirmed,the superiorities of two types of low-water-peak fibers G.652C/D and G.655B/C in supporting full spectrum CWDM transmission and their potential applications in future network upgrade analyzed and their performances compared with those of the dispersion-shifted fiber,negative dispersion（flattened） fiber and other non-principal fibers.  
        关键词：CWDM;fiber type;low-water-peak fiber;NZDSF   
        2
        |
        107
        |
        1
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514518 false
        发布时间：
      • Fu Yanfeng,Liu Qing,Zou Fengting,Zhang Cuihong,Yin Xinda,Jiang Shan
        Issue 5, Pages: 58-61(2006) DOI: 10.13756/j.gtxyj.2006.05.019
        摘要：Fiber-optic access is a hot spot in recent development of Direct Broadcast Satellite（DBS） covering technology and the development of the optical transmitter and receiver for the transmission of the broadband DBS TV signals from new generation Ka-band satellites has currently become an important research question.On the basis of the analysis of the DBS signals and the principle of the optical receiver and in light of the application features of fiber-optic broadband access networks,a 3 GHz analog optical receiver with fairly high sensibility and large dynamic range has been designed and developed for the optical broadband satellite TV signals.  
        关键词：Direct Broadcast Satellite（DBS）;optical receiver;sensitivity;wideband flat response   
        2
        |
        56
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514558 false
        发布时间：
      • Lin Xuefeng~
        Issue 5, Pages: 62-65(2006) DOI: 10.13756/j.gtxyj.2006.05.020
        摘要：A Fiber Bragg Grating（FBG） with weak feedback is utilized to keep an uncooled 980 nm pump laser operating in a coherence-collapse state,greatly improving the stability of its wavelength and output power. The effects of the main FBG parameters on the output power and spectrum of the laser in the experiment are analyzed,which shows that the optimized FBG parameters can stabilize the laser operating over a range of 070 ℃.  
        关键词：FBG;uncooled 980 nm pump laser;coherence collapse;wavelength stabilization   
        5
        |
        167
        |
        5
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514531 false
        发布时间：
      • Issue 5, Pages: 65(2006)
          
        2
        |
        45
        |
        0
        <HTML>
        <Meta-XML>
        <引用本文> <批量引用> 27514382 false
        发布时间：
      • Cheng Lin,Deng Tao,Yang Kuntao
        Issue 5, Pages: 66-67(2006) DOI: 10.13756/j.gtxyj.2006.05.021
        摘要：This paper begins with the introduction of the basic principles of the cladding pumping technology,the technical approach for the realization of high power amplifiers by using the ytterbium-erbium co-doped dual-clad fiber pumped by the high power multimode pump laser and the comparison with that for the conventional Er-doped fiber amplifiers.Then the authors proposed a novel optical structure,i.e.using the conventional EDFA in the first stage to improve NF and ytterbium-erbium co-doped dual-clad fiber pumped by high power multimode laser diode in the second stage to increase the output power.The prototype amplifier with this structure has output power of 30.9 dBm and NF of 5.2 dB.  
        关键词：cladding pumping;erbium-ytterbium co-doped;fiber amplifier   
        2
        |
        183
        |
        2
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514446 false
        发布时间：
      • Zhou Hua
        Issue 5, Pages: 68-70(2006) DOI: 10.13756/j.gtxyj.2006.05.022
        摘要：This article introduces a 1.25 Gbit/s limiting amplifier manufactured by 0.35 μm BiCMOS process,which has single power supply of 3.3 V,circuit gain of up to 70 dB and power dissipation of 20 mW.Within the input dynamic range of 27 dB,it can maintain a constant output swing of 800 mV.The total area of the chip is 1.30 mm×0.75 mm.  
        关键词：optical receiver;limiting amplifier;BiCMOS process;PECL   
        2
        |
        111
        |
        3
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 27514572 false
        发布时间：
      0