最新刊期
卷 ， 期 1 ， 2019
- 摘要：With the explosive growth of data traffic in communication networks,traditional electrical switches will be difficult to satisfy the requirement of broadband network development due to their limited bandwidth and high-power consumption.With optical switches,data can be directly exchanged in the optical domain without conversion.All-optical switching has many advantages such as high speed,wide bandwidth,transparency,low power consumption and low cost.It can be applied in the next generation all-optical switching networks,data center and high-performance computer interconnect networks.This paper introduces the development status and core technologies of integrated optical switches,including the implementation of optical switches using silicon dioxide,III-V semiconductor materials and silicon materials.Among them,the silicon based integrated optical switches have the advantages of compact size,low power consumption,and compatibility with Complementary Metal-Oxide-Semiconductor（CMOS）technologies,which are suitable for massive low-cost production that can potentially find rich market applications.This paper focuses on the implementation of the elementary devices for silicon based optical switches and several representative optical switch fabrics.The methods for the switch state monitoring and switch chip package are also covered.关键词：silicon photonics;optical switch;optical waveguide;integrated photonics
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发布时间： - 摘要：The development of network applications makes the access network traffic complex and diverse.Fine control of access network data traffic has become an urgent need for service operators and managers.Based on the requirement analysis in Ethernet Passive Optical Network（EPON）traffic identification system,a hardware architecture based on Field Programmable Gate Array（FPGA）is presented.The key design scheme of matching engine module is introduced in detail.The test results show that the prototype system can identify the first 64 bytes fixed fields of 10Gbit/s EPON line data frame in line speed without introducing significant latency.It also completes the matching of Ethernet network data and control,and provides effective support for the back-end analysis system for further data parsing.关键词：EPON;traffic identification;deep packet inspection
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发布时间： - 摘要：The selection of alarm transaction set based on time window directly affects the effectiveness of alarm association rule mining,and the internal correlation of Automatically Switched Optical Network（ASON）alarm makes it have a certain clustering relationship.Therefore,we propose a alarm clustering and correlation method based on business time window selection.The multi-network alarm is first clustered according to the network business configuration.Then the time window is divided to generate a more strongly correlated alarm transaction set by determining the alarm growth period.Finally,we also investigate the alarm association rules.This method can adapt to the characteristics of multi-plane and multi-network alarm internal correlation of intelligent optical network,which has the advantages of effectively compressing the alarm transaction set,higher accuracy of alarm association rules,and support for subsequent fault diagnosis.The feasibility and effectiveness of this method are verified by the practical network data.关键词：ASON;network business;time window;alarm clustering;alarm correlation
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- 109
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发布时间： - 摘要：In order to ensure the good condition of the cable,a lot of manpower have been used to conduct inspections,which are inefficiency for the power companies.Current power outage caused by cable failure seriously affects people’s normal life.Therefore,an effective monitoring system is required to monitor the status of the cable online.In this paper,we propose a cable safety monitoring system based on polarization optical time-domain reflectometer.The system judges the intrusion point by calculating the kurtosis coefficient for the different maps.When the system is operating at a pulse width of 1μs,the error on the intrusion localization is less than 100 m.By setting the ring width appropriately,the false alarm rate can be reduced to be less than 0.5%.In the case of different cable lengths and cable layout environments,the requirements for different users can be satisfied by setting the parameters under different system configurations.关键词：distributed optical fiber sensing;cable health monitoring system;polarization optical time-domain reflectometer;intrusion detection;online monitoring platforms
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发布时间： - 摘要：This paper proposes an automatic bias control algorithm for dual parallel Mach-Zehnder modulator which is proposed for 16 Quadrature Amplitude Modulation（16QAM）formats to solve the working points drifting problem in dual parallel MachZehnder modulators.The algorithm is divided into two parts,which are initialization part and tracking locking part.The purpose of the initialization part is to find a working point close to the bias voltage to reduce the time required to lock the working point in the tracking locking algorithm.The tracking and locking parts use the detection method of dithering signal to find accurate working bias point,and track the offset point varying in real time.Therefore,the bias voltage can always stay at the best bias point with small the range of variation.The factors that affect the results of the algorithm are analyzed in the experiment verification.The measured data show that this algorithm can find the best working bias point of dual parallel Mach-Zehnder modulator in a relatively fast time.It also shows the ability to track and adjust the working bias point in real time.关键词：dual parallel Mach-Zehnder modulator;automatic bias control;initialization;tracking locking
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- 66
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发布时间： - 摘要：The dielectric constant is a physical quantity that characterizes the dielectric properties of a material.With the use of microwave dielectrics in aircraft,ships,vehicles,communications,and other fields,the accurate measurement of dielectric constant has become a hot research topic.In order to improve the measurement accuracy of dielectric constant,a microwave non-destructive planar sensor loaded with hexagonal Complementary Split Ring Resonator（CSRR）is proposed.Comparing with the traditional quadrilateral CSRR microstrip resonator,the analysis results show that the hexagonal CSRR microstrip resonator has higher sensitivity than the quadrilateral CSRR,and the quality factor is also improved.Then,the interaction of the resonant frequency and the dielectric constant of the hexagonal CSRR microstrip resonator is studied.The simulation results show that when the dielectric constant of the measured sample becomes larger,the resonant frequency becomes smaller.The negative quadratic and the dielectric constant are linearly related.The analytical data of the dielectric constant and the resonant frequency are obtained by fitting the data of the simulation data,which are verified by measuring the resonant frequency of the sample when loading the measured sample.The proposed measurement method has important reference value in future engineering design.关键词：dielectric constant;hexagonal CSRR;perturbation method;resonant frequency
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发布时间： - 摘要：Aiming at the air-to-ground channel environment of Unmanned Aerial Vehicle（UAV）,this paper presents a MultiInput Multiple-Output（MIMO）channel model for Three-Dimensional（3D）elliptical column UAV in air-to-ground communication environment.In this paper,the mobility and height of the transmitter are studied based on the proposed channel model.The statistical properties of the proposed channel model are studied by considering the reflection of the ground and roadside environments.Finally,the numerical results show that the proposed channel statistics are consistent with the previous communication channel results.The proposed channel model represented by spatial correlation function provides a novel and practical method for the study of UAV channel communication system.关键词：channel model;UAV;channel modeling;MIMO
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发布时间： - 摘要：In order to improve the accuracy of time delay estimation in wireless channel measurements under multipath conditions,a combination of matched filtering,Method of Direction Estimation（MODE）,and Weighted Fourier transform and RELAXation based（WRELAX）are studied.This paper proposes a MODE with extra Roots,which is based on WRELAX（MODEX-WRELAX）algorithm.The corresponding algorithm derivation is also presented in this paper.The new algorithm can not only resolve multipath delay but also suppress noise and strong interference well.Simulation results show that this method provides higher accuracy and resolution than MODE,WRELAX,and MODE-WRELAX algorithms.It also shows that the MODEX-WRELAX algorithm can approach the corresponding Cramer-Rao Bound（CRB）.关键词：multipath channel;delay estimation;WRELAX algorithm
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- 327
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发布时间： - 摘要：In self-organizing networks,nodes are less self-identical,while self-serving nodes do not do their best to forward data to reduce the reliability of the network.Based on this,the joint game theory is established in the dynamic Bayesian framework,and a data transmission algorithm based on Bayesian game is formed.The algorithm first finds out the bad nodes according to the beliefs of each node,and then calculates the joint belief probability of each predicated environment and normalizes the joint existence probability according to the prediction of the network environment by the bad nodes.Next,we calculate the security benefit values of each joint under each joint,and obtain the corresponding contract.Then we use a priori medium to refuse to find the Bayesian steady state contract.Finally,the bad nodes are punished by setting the security capacity to calculate the weights,to ensure that the security capacity and benefits of each node in the federation are maximized and the data is effectively forwarded.The simulation results show that,compared with the other two algorithms,the proposed algorithm not only has less routing delay and control overhead,but also has a higher packet delivery rate,which effectively reduces the adverse effects of the bad nodes on the network.关键词：wireless network;game theory;Bayesian rule;Nash equilibrium;selfish node;punishment mechanism
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发布时间： - 摘要：In a millimeter wave massive Multiple-Input Multiple-Output（MIMO）system,hybrid precoding has become a hot research topic because it can greatly reduce the use of radio frequency links,and solve the hardware loss caused by full digital precoding.In addition,the performance is close to full digital precoding.This paper proposes to use an adaptive connection network,using Zero-Forcing（ZF）algorithm in both analog and digital domains,which can further reduce the hardware costs.The proposed algorithm is simulated on the Rayleigh fading channel and the sparsely scattered millimeter wave channel.The simulation results show that the proposed algorithm can achieve better performance in the adaptive connection network structure,and has higher spectral efficiency than the same structure adaptive algorithm.It also shows that the performance is closer to full digital precoding.关键词：massive MIMO;millimeter wave;hybrid precoding;adaptive connection;analog precoding
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发布时间： - 摘要：This paper proposes the advanced stage after industrial,Internet interconnection:Enterprise-AI Agent（EAI）.It is totally different from intelligent enterprises in attributes,history,relationships,evolution,statistics,centralized control,etc.The definition of EAI,"Why should we build EAI","What are the characteristics of EAI","How to construct at this stage","What is the engineering science and technology of EAI"are given in detail.Among them,this paper emphasizes that an EAI should build two related factories:intelligent and physical（perception part）."Physical factory+ Enterprise Cloud Network+equipment+sensing+big data+algorithm+artificial intelligence"is the basic element.EAI will greatly break through the limitations of traditional enterprises’ capabilities,informational power,space and time.It will reshape enterprise development mode and enterprise organizational structure,and improve the accuracy,efficiency and predictability of enterprise management.关键词：EAI;environmental perception;physical world perception;human social perception;cyberspace perception;smart factory;industrial Internet
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