最新刊期
卷 32 ， 期 5 ， 2016
- 摘要：2016 is the 50th anniversary of Charles K Kao's proposing using optical fiber communication,the article was written to commemorate the review,in particular,the development review of China's optical fiber communication.Zhao zisen was one of the founders of Chinese optical fiber communication,the development of China's optical fiber communication was reviewed and the successful experiences and failure were absorbed.关键词：optical fiber communication;review;fiber material877|1772|0更新时间：2024-06-05
- 摘要：The rapid progress of optical fiber communication makes it become the key technology for the information society.The active and passive optoelectronic devices are the foundation of the optical communication.The progress and development trend of the key active optoelectronic devices were reviewed,including DFB laser,photonic integrated circuit,980 nm high power laser for EDFA pumping,compound semiconductor photodetector and Si-based long wavelength photodetector.关键词：optical fiber communication;active device;DFB laser;pumping laser;photodetector;avalanche photo diode1093|3435|0更新时间：2024-06-05
- 摘要：As the core of the information network infrastructure,optical network has an irreplaceable important role.The birth process of optical network and the important milestones in its 30 years research and development course were reviewed firstly,then the challenges and possible development trends of optical networks according to future network demands were discussed.关键词：wavelength division multiplexing;automatic switched optical network;software defined network;all-optical network;converged packet-optical network;converged wireless-optical network1028|2067|0更新时间：2024-06-05
- 摘要：Optical fiber communication system is one of the core supporting systems of the modern internet age.Firstly,major recent technological advances in optical fiber communication system were summarized.Then,the driving forces for its future development in the emerging cloud era,the future challenges and opportunities that it faced were analyzed.With the consideration of these challenges and opportunities,the future evolution paths in key areas such as optical fiber communication system overall network architectures,core network technologies,metro network technologies,access network technologiesand novel software-defined optical transport network technologies in the upcoming cloud erawere described,aiming to support future generations of internet,data center interconnect,internet of things and 5G mobile network,as well as the smart home and smart city initiativesmore effectively.关键词：optical fiber communication;cloud era;optical transport network;data center interconnect;5G mobile network;smart home and smart city1742|5364|0更新时间：2024-06-05
- 摘要：Due to the fast growth of internet services,datacenter related traffic has become the major part of the global network traffic.As a main technology for high-speed data transmission,optical communication technologies have been widely used in today's datacenter networks,from a few meter server-to-server interconnects to transoceanic datacenter-to-datacenter optical networks.Here the optical communication technologies for datacenters were reviewed,including technologies connecting datacenters in wider-area networks and metro-area networks as well as optical interconnect technologies within datacenters,and the advantages and disadvantages of some technologies in the networks were discussed.关键词：datacenter;optical communication;wide-area network;metro-area network;optical transceiver1366|3403|0更新时间：2024-06-05
Special topics：50 anniversary of the invention of optical fiber
- 摘要：Cognitive radio technology has achieved the dynamic allocation of spectrum resources,and improves the utilization rate of spectrum resources.Accurate and efficient spectrum sensing is the key step in cognitive radio.Developing a fast and high-performance spectrum sensing method has become an urgent problem to be solved.In recent years,goodness of fit（GOF）theory has been applied widely in the field of spectrum sensing and the effective spectrum sensing technology under small sample point has been implemented.Therefore,the research on spectrum sensing technology based on GOF has very significant value.The development process of GOF in areas of cognitive radio spectrum sensing was summarized,its basic principle common fitting criterion and fitting object were introduced.The simulation comparison of the algorithm was carried under the Gaussian channel and its prospects of further research was forecasted finally.关键词：cognitive radio;spectrum sensing;goodness of fit test;fitting criterion;fitting object544|836|0更新时间：2024-06-05
- 摘要：There are discrete optimization problems for spectrum allocation in cognitive wireless network.A novel combinatorial optimization algorithm called quantum cuckoo search algorithm （QCSA）was proposed,which was based on quantum computing and cuckoo search algorithm.The quantum nest was used to represent multiple dimensionality solution for the optimization problem,and the global optimal position was found according to Lévy flights and quantum mutation strategy.In additional,some classical benchmark functions were employed to prove the effectiveness of QCSA,and a spectrum allocation method based on QCSA was proposed for cognitive network.Compared with classical spectrum allocation methods by using different network utility functions,the global optimal solution can be searched so fast.Simulation results show that the proposed spectrum allocation method based on QCSA is better than other traditional methods under different network utility functions.关键词：cognitive wireless network;spectrum allocation;discrete optimization problem;quantum computing;cuckoo search algorithm381|688|0更新时间：2024-06-05
- 摘要：To solve the existing problems of low recognition rate and noise problem in radar signal recognition,the fusion feature extraction method of time-frequency image and the random forest classifier is applied to the identification of radar signals.The radar signal time-frequency image was firstly extracted the shape features and texture features to anstitute fusion characteristics,into and then input fusioncharacteristics radom forest classifier recognition of the signal classification was realized.The results of simulation experiments for eight kinds of common radar signals to recognition show that recognition accuracy of the method proposed can be achieved more than 90% in SNR -2 dB,so it also verify the effectiveness of the method.关键词：radar signal recognition;ime-frequency image;fusion feature;random forest626|1124|0更新时间：2024-06-05
- 摘要：A resource allocation algorithm based on double slots was proposed to minimize the transmitting power in wireless communications.Being aware of the channel difference between the two adjacent slots,the second slot was allocated in advance partial of the data rate conventionally scheduled to the first slot when the corresponding user had perfect channel state.Consequently,most of the required data was loaded by the sub-carriers with fine channel gain and finally less transmitting power was needed.The simulation results indicate that the proposed algorithm can effectively decrease the transmitting power while meeting the users' target rate requirement.关键词：double slots;rate allocation;sub-carrier allocation;power allocation;power minimization392|799|0更新时间：2024-06-05
- 摘要：A contract-based cooperative spectrum sharing model in cognitive radio network was proposed.In this model,secondary user offers relay service for primary user when primary user's channel is poor.In return,when primary user's channel is good,secondary user can use spectrum with the underlay mode under the condition that the interference is limited.Contract theory in economics was introduced to this framework,the problem of collaboration between the primary and secondary users was modeled as a contract design problem,and the effectiveness function of evaluate primary and secondary users on contract revenue was set up.And the differential evolution algorithm was used to solve the problem.Finally,in different circumstances,primary user collaboration and un-collaboration were contrasted.The results showed that the main users under the condition of no additional input spectrum,not only save the sending power,but also effectively improve the data transfer rate,and improve the energy efficiency and spectrum efficiency.关键词：cooperative spectrum sharing;contract theory;optimization problem;differential evolution algorithm330|618|0更新时间：2024-06-05
- 摘要：Due to the high computational complexity of massive MIMO system,a low-complexity sparse channel estimation algorithm was proposed utilizing the inherent sparsity of the wireless communication channel to improve the estimation performance.The proposed algorithm separated channel tap from noise space based on the traditional discrete Fourier transform by adopting integral separation algorithm.This channel estimation algorithm need only calculate the channel tap,thus markedly reducing complexity of the algorithm.Numerical simulations show that proposed algorithm can approach to the performance of the minimum mean-square error estimator while maintaining lower complexity.关键词：massive MIMO;channel estimation;sparsity;algorithm complexity465|890|0更新时间：2024-06-05
- 摘要：As the problem of fuzzy inquiry and data sparseness cased by intention gap between users and queries,according to the ranking list of possible subtopic from popularity and diversity,subtopic selection and sorting of stratified structure were used for web text mining.Firstly,on the basic of noun phrase and substitute of part query,a simple model was used to extract a variety of related phrases as candidate subtopic.Then,related documents of a web document collection were used to build three-level stratified structure of candidate subtopic.Finally,considering popularity and diversity,the stratified structure and estimated popularity were applied for sorting.Based on 100 Japanese queries from NTCIR-9 library,100 English queries from TREC 2009 library and network tracking diversity task,experiments verify that the proposed method can be effectively applied to a variety of search,and the proposed mining is better than external resources for high ranking subtopics.关键词：data sparseness;text mining;stratified structure;diversity,popularity262|854|0更新时间：2024-06-05
- 摘要：SVM is a typical machine learning algorithm with prefect generalization capacity,which is suitable for the internet traffic classification.At present,there are two approaches,One-Against-All and One-Against-One,proposed for extending SVM to multi-class problem like traffic classification.However,these approaches are both based on a unique feature space.In fact,the separating capacity of a special traffic feature is not similar to different applications.Hence,flexible feature space for extending SVM was proposed,which constructs independent feature space with optimal discriminability for each binary-SVM and trains them under their own feature space.Finally,these trained binary-SVM were ensemble by One-Against-All and One-Against-One approaches.The experiments show that the proposed approach can efficiently improve the precision and callback of the traffic classifier and easily obtain more reasonable optimal separating hyper-plane.关键词：support vector machine;flexible feature space;traffic classification423|628|0更新时间：2024-06-05
- 摘要：In order to prevent personal data from being lacked and improve the existing mobile network roaming anonymous authentication scheme,anonymous security authentication scheme using elliptic curve cryptography and hash functions in mobile network was proposed.With elliptic curve cryptography and hash functions,random numbers were used to replace public key encryption and time stamp.Firstly,before using the roaming services of a foreign agent（FA）,hash function was calculated.A host agent（HA）was used by mobile user to register.Then,authentication and session key were set up with elliptic curve encryption.If HA is always in FA,MU can update the session key with FA.Finally,through a common channel,MU could utilize HA to change their passwords.The analysis of the performance and safety shows that,compared with other similar programs,the proposed scheme has significantly improved efficiency and safety.And the virtual computing time is only 2.000 85 seconds,which sharply reduces the cost of computing.关键词：mobile network;anonymous security authentication;elliptic curve cryptography;hash function;impersonation attack371|604|0更新时间：2024-06-05
- 摘要：For the issues that the existing RFID security authentication scheme based on elliptic curve cryptography （ECC）can not meet the requirements of mutual authentication,privacy protection and forward security,a RFID security authentication scheme based on Montgomery-form elliptic curve cryptography was proposed.This scheme uses the Montgomery elliptic curve to reduce the amount of computation,and to provide mutual authentication between the label and the server,and anonymity and forward security.The analysis showed that the scheme could resist replay attack,tag camouflage attack,server cheat attack,DoS attack,position tracking attack and clone attack.Compared with the existing schemes,the proposed scheme provides high security performance under low memory,computation and communication requirements,and it can meet the security requirements of the RFID system.关键词：RFID;security authentication;elliptic curve cryptography;Montgomery;forward security458|710|0更新时间：2024-06-05
- 摘要：Using Meijer-G function,exact expression for the random coding error exponent,ergodic capacity,cutoff rate,expurgated exponent of TAS/MRC Nakagami-m fading channel were derived.Numerical results show that the random coding error exponent is related to channel fading coefficient,coding rate,the number of transmitting and receiving antennas,and signal symbol period.With the coding rate,the number of the receiving and transmitting antennas and the average signal to noise ratio increasing,the RCEE of the system will become larger and the BER performance of the system will be better.For a given decoding error probability of a wireless communication system,necessary coding length,number of antennas,channel coherence time,and spatial fading correlation could be estimated by computing the random coding error exponent.关键词：Nakagami-m fading channel;TAS/MRC technology;random coding error exponent;ergodic capacity;cutoff rate;expurgated exponent333|681|0更新时间：2024-06-05
- 摘要：Android system has occupied the majority share of smart mobile operating systems.However,Android system has worrying security issues.It frequently bursts high-risk vulnerabilities in recent years,which is a big security risk to the majority of Android users.Android system vulnerabilities were studied,and a rapid detection method of Android system vulnerabilities based on matching was proposed.A script-based vulnerability scanning tool was also designed.Through the evaluation of experiments,the tool is running well.关键词：Android;matching;vulnerability detection685|1459|0更新时间：2024-06-05
- 摘要：The emerging fiber-wireless（FiWi）broadband access network provides not only the new technological references for flexible broadband access anywhere and anytime,but also the research opportunities for the cost-efficient design of survivable broadband access network.The study of survivable FiWi access network planning was focused on,and an approach of survivable network planning based on wireless-rerouting protection was proposed.When any fiber link cuts,the failed optical network unit（ONU）can transfer its traffic into other normal ONUs.Solving the joint optimization problem of wireless routers placement,backup radios configuration and ONU capacity allocation was put more importance on,aiming to fully protect all traffic with the minimum deployment cost.The method of integer linear programming was employed to obtain the optimal solution for small-scale network planning.The heuristic algorithm was also proposed for the large-scale network planning.Simulation results demonstrate the effectiveness of the proposed approach in reducing network deployment cost.关键词：fiber-wireless;survivable network planning;wireless rerouting;network protection;backup resource437|982|0更新时间：2024-06-05
- 摘要：With the advancement of information and industry strategies,5G technologies,and mobile internet,scarcity of radio spectrum resources highlighted again.Spectrum sharing provides a solution to the problem of spectrum scarcity.It is currently and actively under research by the international mainstream countries.Based on the analysis of domestic and international spectrum sharing research and application,the purposes and challenges of the spectrum sharing were further discussed,feasibility assessment framework for spectrum sharing was provided,and some suggestions were proposed to promote the implementation of spectrum sharing.关键词：spectrum resource;spectrum sharing;radio management317|2022|0更新时间：2024-06-05
research and development
- 摘要：Smart grid refers to the next generation power grid in which the electricity distribution and management are upgraded by combining the power grid and power communication network（called dual network）.According to the problems,such as the power spatial information sharing of multi-business integration problem,the thematic application and the dynamic display etc,the new power unified spatial information model（PUSIM）was proposed for smart grid dual network.Based on the abstract layer,entity layer and business layer,PUSIM builded the geometric object,topology relationship and the conceptual model and logical model of account property for the dual network,and constructed the unified model,expression and integration management for the dual network based on common information model.关键词：smart grid;dual network;unified spatial information model;conceptual model;logical model525|1204|0更新时间：2024-06-05
- 摘要：An algorithm model conformed to the user behavior,based on the massive IPTV user characteristic data which extract rules and classify IPTV users was proposed.First,IPTV user group description dimension in accordance with the user on demand was put forward.Namely,the user group could be described by basic property and trend of user behavior could be described by users' demand behavior.Then the concept of prediction measurement was put forward,the stability of user group was described,and an algorithm which extracted demand behavior probability on stable user group was proposed.At last,the algorithm model was verified and analyzed by massive IPTV operation data.关键词：IPTV;demand behavior;equivalent class;information entropy;prediction measurement;rule extraction418|1551|0更新时间：2024-06-05
- 摘要：Southbound interface protocol specification I2RS（interface to routing system）appears in the transitional period of traditional network to SDN（software defined networking）.Based on the protocol specification,a method which could get the state and statistics information of network's equipments in a more efficient way was put forward.The design was detailed and adequately testing was performed,which included the speed of getting information about equipments' state and statistics,the numbers of the wrong information as well as the recovery time from exception.The experiment results show that the proposed method improves the speed of getting the information about equipments' state and statistics,which is better than the existed method and when some exceptions happen,the proposed method can recover the situation quickly.The application of the real network environment shows that the proposed method can get the wanted information quickly and stably.关键词：SDN;I2RS;south bound interface;routing equipment;operating system367|624|0更新时间：2024-06-05
- 摘要：According to the analysis requirement of the space probe performance of 2-D spectrum estimation algorithm,a brief introduction of the 2-D spectrum estimation algorithms was given in the view of calculating speed,calculating volume,stability,accuracy and practical application.These algorithms were the spectrum estimation algorithms of the 2-D MUSIC,the 2-D interference and the 2-D MEMP with the L-shaped array.The estimation performance of the algorithms were analyzed by simulations,the angle root mean square error of three algorithms were compared and analyzed.Simulation results show that the performance of the 2-D MEMP is the best,the performance of the 2-D interference algorithm is the worst,and the performance of the 2-D MUSIC is moderate.Meanwhile,the experimental scene was constructed,and the space probe performance of the 2-D spectrum estimation algorithm was analyzed by real data.The experimental results were consistent with the simulation results.Based on this,the 2-D MEMP algorithm may be further applied in the radar and TT＆C system.关键词：space probe;2-D spectrum estimation;array manifold;angle root mean square error;non-cooperative target detection;TT＆C system294|926|0更新时间：2024-06-05
- 摘要：The traditional way was used to qualitatively describe the IPv6 communication capabilities for end-to-end carrier grade network with many old devices.By introducing concepts of IPv6 communication events,IPv6 communication capability index,the algorithms were presented to calculate the IPv6 communication capability index for single node,node set,single path,multi-path and end-to-end network.These algorithms were also used to analyze and evaluate the IPv6 communication capability for end-to-end carrier grade network.关键词：IPv6;IPv6 communication event;IPv6 communication capability index;quantitative analysis method324|779|0更新时间：2024-06-05
- 摘要：The historical trajectory detection plays a vital role and has the practical significance for commercial userbehavior analysis， the identity of the police suspect landing and surveillance of key. Current detection methods usemobile client silence to collect user information， or use operators to shunt data， or shooting combined with artificialanalysis. The ways have many disadvantages such as the sample is limited， the effective information is difficult toextract and the analytical efficiency is low. A historical track detection based on Wi-Fi protocol was proposed， andspecific system design and function relization were given which provided a new way to analyze the behavior of users.关键词：Wi-Fi;trajectory detection;probe request335|1036|0更新时间：2024-06-05
- 摘要：After comparing and analyzing the main business and implementation plan for an enterprise content management platform web service,a technical scheme was put forward,which was using a table interface combined with the CXF framework,taking both responsiveness and stability requirements for web services into account,while also facilitating configuration adjustments due to the frequent change of business requirements.On the basis of that,a web service configuration module was developed to enhance the web service's scalability.关键词：CXF framework;enterprise content management platform;Web service;configurable266|990|0更新时间：2024-06-05
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