最新刊期
卷 ， 期 1 ， 2008
- 摘要：The performances of the prioritized burst retransmission scheme and the segmentation-based IP retransmission scheme in optical burst switching（OBS） networks are analyzed and compared.The results indicate that the former is an ideal retransmission option as in this option,the frequency of retransmission and the needed size of buffer and the retransmission delay can be effectively reduced,and the network throughput improved.关键词：OBS;burst contention;burst retransmission;IP retransmission
- 2
- |
- 65
- |
- 1
发布时间： - 摘要：Centralized control is usually adopted for the conventional network management platform.This paper introduces a new concept for the design of the distributed fault management module,which is based on the location of the distributed fault points and the span distributed recovery algorithm.The main purpose of this design is to overcome recovery delay and traffic loss due to the previously long time spent for centralized fault and alarm reports.It is applicable to different optical networks.关键词：distributed fault management;alarm;fault location;fault recovery;optical network
- 2
- |
- 90
- |
- 1
发布时间： - 摘要：We first define the framework of the Optical Service Level Agreement（O-SLA） by comparing with SLA from the angle of the service optical network,on the basis of which we center our analysis on its negotiation mechanism,present the concept of a dynamic negotiation and investigate the implementation flow of its mechanism.Then we summarize the crucial technology for the effective implementation of O-SLA and present the implementation flow of O-SLA supporting differentiated services,which provides a new idea of offering customized optical layer services to the edge users.关键词：O-SLA;overall framework;intelligent service optical network;dynamic negotiation mechanism;differentiated service flow
- 2
- |
- 75
- |
- 1
发布时间： - 摘要：ROADM enables the configuration of drop,add and express wavelengths at remote nodes via software control.In this paper,the evolution of ROADM technologies is first presented.Then,WSS-based ROADM with different architectures are compared and different performances obtained by different logical ways of implementation.Finally,approaches for WSS implementation are discussed.关键词：ROADM;WSS;MEMS;PLC
- 2
- |
- 524
- |
- 1
发布时间： - 摘要：With the development of the telecommunication industry,the demand for centralized management has been increasingly urgent and it has become an irreversible trend of development for transport network management to change from the NE level to the end-to-end level.This paper first points out the problems in the circuit search process in general.Then,it specifically analyzes the cross connect and circuit search problems for FiberHome equipment in its on-line projects.At last,it describes the algorithm,operating procedure and project cases of the software Zpath used for circuit search that the author has developed.关键词：cross-connect on NE;end-to-end circuit management;circuit search
- 2
- |
- 27
- |
- 1
发布时间： - 摘要：Large amounts of logic circuits are required for the frame alignment and rearrangement of the input data in the design of ASIC chips for the high-order broadband（STM-16） circuit switching.A frame alignment circuit design by using the pipeline technology is presented and two different circuit design schemes for the above functions given.The test results show that by using this scheme the circuit size is obviously reduced,the chip power consumption decreased and its reliability and performances improved.关键词：SDH;pipeline;frame alignment;data rearrangement
- 3
- |
- 58
- |
- 2
发布时间： - 摘要：By reference to the latest research developments at home and abroad,various conventional wavelength assignment algorithms are investigated in view of the burst resource contentions in Optical Burst Switching（OBS） networks with limited wavelength conversion capabilities.A novel dynamic wavelength assignment algorithm that suits this kind of networks is proposed on the basis of the analysis and comparisons of their characteristics.This algorithm promises still lower burst blocking rate in OBS networks.关键词：optical burst switching;wavelength converter;wavelength assignment algorithm
- 2
- |
- 65
- |
- 2
发布时间： - 摘要：A novel user receiver model is proposed to cope with the existence of NarrowBand Interference（NBI） in a hybrid WDM/OCDMA system.It is theoretically deducted that the NBI between WDM users can be completely suppressed in this scheme.At the same time,simulation results prove that the system BER is significantly lowered,the system performance improved and the BER is the minimum when the normalized threshold is about 0.28.关键词：OCDMA;WDM;hybrid WDM/OCDMA system;NBI;MUI
- 2
- |
- 114
- |
- 1
发布时间： - 摘要：This paper proposes a novel 60GHz millimeter-wave Radio-Over-Fiber（ROF） downlink system that is based on the harmonics generation technique and employs optical PSK modulation.While millimeter waves are generated at base station,BPSK modulation is realized.In addition,pilot tone injection is implemented by adding a parallel optical DSB-SC modulation path for the millimeter-wave donwnconversion.The simulation results verify the millimeter-wave generation technique and the signal modulation and demodulation,which testify to the feasibility of the proposed millimeter-wave downlink system.关键词：millimeter-wave;harmonic generation;optical PSK modulation;ROF;pilot
- 2
- |
- 330
- |
- 1
发布时间： - 摘要：While considering the fourth-order dispersion and the quintic nonlinearity of optical fibers with losses,we investigate the Cross-Phase Modulation（XPM） instability caused by two beams of lights on the basis of the extended nonlinear Schrdinger equation.The results show that due to of the effect of the fourth-order dispersion,XPM instability may occur in two spectral regions in both the normal and anomalous dispersion regimes of the fibers and the positive and negative quintic nonlinearity will intensify and weaken the XPM instability respectively.关键词：cross-phase modulation instability;fourth-order dispersion;quintic nonlinearity
- 2
- |
- 204
- |
- 4
发布时间： - 摘要：In order to increase the coupling efficiency the pumped light in DCF,we first investigate the effects of the ratio of the core diameter to the inner cladding size on the absorption efficiency in DCF with a constant refractive index.Then,we study the optimization of the offset of the fiber core by simulation of the pumped light.The numerical simulation results show that the absorption efficiency is the maximum when the offset is R-r,i.e.when the core is located in the margin of the inner cladding.Finally,we discuss the effects of the inner cladding of the graded index fiber on the coupling efficiency.关键词：DCF;absorption efficiency;offset
- 2
- |
- 165
- |
- 9
发布时间： - 摘要：The fundamental concept of optical fiber PMD and the factors affecting PMD are introduced in this paper.On the basis of analyzing the relationship between the cladding noncircularity and PMD through a series of tests,it is indicated that in order to control the stability of fiber PMD and the reliability of the PMD values measured when the fiber is rewound on the bobbin,it is necessary to control the cladding noncircularity within a reasonably small range,which can be extended by the fiber spinning technology.关键词：optical fiber;PMD;fiber cladding noncircularity;fiber spinning
- 2
- |
- 178
- |
- 5
发布时间： - 摘要：An MCU-based fuzzy control technique for fiber drawing machines is developed.With the laser caliper gauge as the feedback component and the MCU as the actual carrier of the fuzzy controller,the expert system-based control rules are formulated,realizing the closed-loop control over the drawing machines.The application results indicate that the control system operates as required and has good values in practical applications and popularization.关键词：fiber drawing machine;fuzzy control;MCU;closed-loop control
- 4
- |
- 178
- |
- 1
发布时间： - 摘要：The strict solutions of the elliptical optical waveguide are studied using the polarized light of the incident ray in cylindrical coordinate system,accurate analytical solution of the mode field distribution obtained and the mode characteristic equations derived.When light is transmitted in single mode only in the meridional plane along the long axis,single mode single polarization transmission can be achieved.Compared with the rotundity optical waveguide,the transmission constant of the elliptical optical waveguide changes very little under the same conditions for single mode transmissions.In addition,the effects of wavelength,ellipticity and relative refractive index difference on the transmission constant are briefly analyzed.关键词：elliptical optical waveguide;rotundity optical waveguide;characteristic equation;single mode transmission;transmission constant
- 2
- |
- 205
- |
- 0
发布时间： - 摘要：The Optical Fiber Sensing（OFS） technology has been rapidly developing with the evolution of the optical communication technologies and has become one of the main research subjects in the sensing area,in which the environmental monitoring technology using the wavelength shift of FBG is being perfected.As an effective technique for wavelength testing and characteristic of compact package and high reliability,Optical Performance Monitoring（OPM） module can be used to perform accurate monitoring of wavelength shift.In this article,the working principle of FBG and the technical features of OPM are systematically stated and a sensor testing platform is set up on the basis of combining them.关键词：OPM;OFS;FBG
- 2
- |
- 183
- |
- 1
发布时间： - 摘要：Optical fibers for sensing are first selected for different applications on the basis of in-depth analysis of their physical characteristics.Then a Brillouin scattering spectrum measurement system based on the all fiber Mach-Zehnder interferometer is built,the qualitative measurement of the Brillouin frequency shift of the chosen fibers in normal temperature and the temperature dependence of G.652 fibers respectively performed.Finally,a Brillouin scattering-based time domain reflectometer is designed.关键词：optical fiber sensing;temperature;strain;ocean;tube
- 4
- |
- 309
- |
- 3
发布时间： - 摘要：On the basis of the Attenuated Total Reflection（ATR） principle,a novel solution for the filter design is presented.As we know,high-order guided modes excited in ATR configurations are highly wavelength dependent.Utilizing this characteristic and the electro-optic characteristics of organic polymers,a newly-structured tunable filter is fabricated with merits of lower insertion loss,simpler fabrication process,lower cost and stronger stabilization as compared with other types of tunable filters.Moreover,a narrowband tunable filter with 0.4 nm bandwidth can be obtained by further parameter optimization.关键词：optical device;narrowband filter;ATR;polarized polymer
- 2
- |
- 70
- |
- 0
发布时间： - 摘要：In view of various deformations of ridge waveguide devices in use,we conduct secondary programming by using the finite element PDE toolbox in the Matlab environment to obtain the transmission characteristics of the waveguide in displacement deformation and different deformations under stress.Numerical analysis results indicate that displacement deformation elongates the cutoff wavelength of the ridge waveguide and in the case of single-mode bandwidth,the increase is less than 2%,while greater effect on the ridge waveguide is produced by the deformations under stress in both sides with over 10% changes in its characteristics when the deformation reaches 10%,to which we should pay much attention in practice.关键词：finite element method;ridge waveguide;cutoff wavelength;single-mode bandwidth
- 2
- |
- 101
- |
- 7
发布时间： - 摘要：On the basis of the Helmholtz equation,the 3D Finite-Difference Beam Propagation Method（FD-BPM） is deducted,which is used in AWG simulations to compute and simulate the transmission process of the optical field in the array waveguide.The results show that the computation accuracy is improved by using 3-D BPM.Furthermore,as the 3-D BPM is insensitive to portrait step size,the calculation time can be shortened by increasing the step size,thus improving the accuracy with little effect on the calculation time.关键词：3-D FD-BPM;Helmholtz equation;AWG
- 5
- |
- 150
- |
- 0
发布时间： - 摘要：In this paper,we report a novel method for the control of the photonic band gap of photonic crystals（PC）.PC waveguides can be obtained by infiltrating silicon resin into the air regions in 2D photonic crystals composed of square lattices of dielectric cylinders.The refractive indices of silicon resin can be changed by temperature.Numerical simulation results show that the band gaps of the photonic crystal can be tuned by temperature manipulation,which can be used for making novel optical switches and field-sensitive polarizers in photonic integrated circuits.关键词：photonic crystal;photonic band gap;plane wave expansion method;silicon resin;optical switch
- 6
- |
- 160
- |
- 3
发布时间： - 摘要：On the basis of the investigation of the digital home mode,this paper proposes the model of an intelligent Home Network System（HNS）,which consists of four subsystems for security,monitoring,message transfer and medical care.Their coordinated operations make transparent digital services always and everywhere available in homes.In other words,with the integrated HNS,it is possible to perform remote monitoring of home appliances,automatically sound the alarm and provide medical care by interconnections with the medical facilities.关键词：home network;SMS;remote monitoring;mobile communication
- 4
- |
- 296
- |
- 7
发布时间： - 摘要：From aspects of estimation range,estimation accuracy and calculation complexity,five existing frequency offset estimation algorithms are studies and emulated,and the basis of their selection and detailed analytical results given.On this basis,the joint frequency offset estimation algorithm for TSO-based Midamble code and SYNC-DL code is studied by using the differential correlation method and the estimation range and calculation complexity analyzed.It is found from emulation that frequency offset can be controlled within ±0.05×10-6 by using this algorithm and accurate estimation in the signal acquisition system well achieved.关键词：TD-SCDMA system;frequency offset estimation;performance analysis
- 4
- |
- 297
- |
- 8
发布时间：
- Postal code：430205
- Technical support is provided by Beijing Founder electronics co., LTD 鄂ICP备2022010197
鄂公网安备 42011202002092号 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
- Total Visits：75845
0