最新刊期
卷 32 ， 期 9 ， 2016
- 摘要：Device-to-device(D2D)communication is a promising component in the fifth generation systems,and it can significantly improve both system-side and user-side performance.However,the prior works are mainly focused on addressing the system-side metrics.Therefore,a balance was struck between EE and UF by joint consideration of power control(PC)and temporal and spectral scheduling(TSS).Specifically,PC was intended to maximize the EE of the D2D user.Based on the above results,TSS determined the set of admitted D2D users and their allocated spectral resources.Moreover,the weights were updated by the idea of proportional fairness dynamically.Finally,the numerical results show the efficiency of the efficiency mechanism and the tradeoff between EE and UF.关键词：device-to-devicecommunication;energyefficiency;userfairness;powercontrol;temporalandspectralscheduling862|1081|0更新时间：2024-06-05
- 摘要：A low-complexity hybrid precoding method was proposed to design the hybrid precoding for mmWave massive MIMO system.Firstly,an initial radio frequency(RF)precoding matrix was constructed based on the singular value decomposition.Then an updated RF matrix was constructed by placing the vector which was constructed by the biggest left singular vectors of the residual matrix onto the last column of the initial RF matrix.By multiple iterations,the resultant RF precoding matrix can be obtained and the digital precoding matrix was designed based on the least square criterion.Theoretical analysis and simulation results show that the proposed algorithm greatly outperforms the hybrid precoding method based on orthogonal matching pursuit(OMP)algorithm with much reduced computational complexity.Additionally,the proposed hybrid precoding method has almost the same performance as the full digital precoding method when the number of data stream is relatively less.关键词：mmWave;massiveMIMO;lowcomplexity;hybridprecoding801|2009|0更新时间：2024-06-05
- 摘要：Massive multiple-input multiple-output(MIMO)brings huge improvements in energy efficiency and reduces emission power by using a large number of antennas,which is known as a key technology in the fifth generation (5G)mobile communication.With the increasing number of antennas,the complexity of signal detection is increasing at the same time.According to the research status of massive MIMO signal detection,approximate message passing algorithm was proposed.The complexity of AMP was compared to some iteration algorithm like Richarson algorithm and Neumann series approximation algorithm.The results indicate that the proposed algorithm can use less iteration to achieve almost the same performance of MMSE algorithm.关键词：massiveMIMO;signaldetection;approximatemessagepassingalgorithm;MMSE;errorbitrate765|2114|0更新时间：2024-06-05
- 摘要：With the rapid development of wireless technology,the wireless communication offers great flexibility and convenience to mobile users.However,due to the slow/fast fading caused by multipath effect,the transmission rate of wireless fading channel is unstable,which will affect the transmission delay and communication quality.In literature,the wireless fading channel is also called Markov channel.The transition of channel state is controlled by a Markov chain.A detailed analysis was given for a three-state Markov channel.The whole system was modeled as an M/MMSP/1 queuing system considering the arrivals and services of packets.By defining conditional start service probability and conditional expected delay,the analytical expressions of mean service time and mean waiting time of packets were given using the state transition matrix.At last,by discussing the mean waiting time in limiting cases,the factors that affect the delay were given.关键词：Markovchannel;statetransitionmatrix;startserviceprobability;meanwaitingtime720|1217|0更新时间：2024-06-05
- 摘要：Design of multi-branch dual-hop phase-only forward(PF)cooperative systems with continuous phase frequency shift keying(CPFSK)modulation needs to determine the number of branch and modulation index.The usual solution of determining the above parameters is the time-consuming and inefficient computer simulation.An efficient solution of determining these parameters is theoretical analysis method.Semi-analytical expressions for the average bit error rate(ABER)of multi-branch dual-hop PF cooperative systems in conjunction with discrimination detection CPFSK over time-selective Rayleigh fading channels was presented.Two cases with and without antenna selection at the relays and maximum-ratio combining(MRC)receive diversity at the destination were considered.The simulation results show that numerical calculation results and simulation results for the ABERs of PF，discrimination detection,CPFSK cooperative systems are consistent and show that the above ABER theory results of CPFSK cooperative systems can be used to design PF cooperative systems.关键词：CPFSK;phase-onlyforward;cooperativecommunication;discriminationdetection;maximum-ratiocombining;antennaselection302|704|0更新时间：2024-06-05
- 摘要：As an alternative of the fifth generation mobile communication system waveforms,generalized frequency division multiplexing(GFDM)which has more advantages over OFDM has been trusted into the limelight.Nevertheless,GFDM still suffers from a high peak to average power ratio(PAPR).Considering that different filters have their own phase-frequency characteristics,a new algorithm based on randomly assigning filters to reduce PAPR in GFDM(RAF-GFDM)was proposed.According to the feature of GFDM system that the filter structure could be selected flexibly,different filters were assigned to subcarriers randomly to adjust the phase congruency due to signals superimposition.Additionally,this method can suppress PAPR effectively without causing signal distortion.Theoretical analysis and simulation results demonstrate that the proposed algorithm does not bring additional calculation costs while reducing PAPR and almost has no effect on the bit error rate(BER),and it may provide a higher application value.关键词：GFDM;RAF-GFDM;PAPR;randomlyassignfilter;BER495|1162|0更新时间：2024-06-05
- 摘要：By reusing the resource of existing cellular users,D2D (device-to-device)communication underlaying cellular network can improve the spectrum utilization rate and reduce the power consumption of mobile terminals.However,it will bring interference to the existing cellular networks.In order to ensure the quality of service of D2D users and cellular users,the power control and resource allocation scheme for D2D communication underlaying cellular communications was studied.Specifically,fractional frequency reuse was introduced to achieve the resource partitioning and resource reuse between cellular users and D2D users.Based on the principle of maximizing the throughput of the whole system,the optimization objective was established.Combined with the fractional power control and introduction of interference limits,a dynamic power control strategy was proposed.Simulation results show that the proposed scheme improves the performance of the overall system.关键词：D2Dcommunication;interferencecoordination;fractionalfrequencyreuse;resourceallocation;fractionalpowercontrol398|1055|0更新时间：2024-06-05
- 摘要：To improve the reliability of spectrum sensing in cognitive radio system,a new cooperation spectrum sensing algorithm was proposed.In this algorithm,the property of the low probability between adjacent frames of the states change was used and then the decision was made by combing the energy value of the current sensing frame with that of the neighboring frame.Therefore,the proposed algorithm could decrease the miss detection probability in case of the instantaneous signal energy dropping when primary user used the licensed spectrum.Furthermore,theoretical expressions for detection probability and false alarm probability were derived.Finally,theoretical analysis and simulation results verify that the detection performance of the proposed algorithm is better than that of cooperative spectrum sensing which is based on the classical energy detection.关键词：cooperativespectrumsensing;detectionprobability;secondaryuser;primaryuser812|1269|0更新时间：2024-06-05
- 摘要：In wireless sensor network(WSN),the relay node deployment performance is one of the main factors to affect network life.Aiming at the WSN with 3-demension high density,there is no existing relay node deployment schemes enhancing the network life efficiently with the constraints of hardware cost and network connectivity.Hence,a novel deployment scheme called artificial bee colony(ABC)-based relay node deployment scheme(ABC-RNDS)was proposed based on network-grid deployment method.In ABC-RNDS,double-layer topology was adopted to build WSN,which used minimum spanning tree to construct the backbone nodes of WSN,and applied ABC to extend the network lifetime by optimizing network parameters and constraining the number of relay nodes.The simulation results show that,compared to the traditional deployment scheme,ABC-RNDS can improve network lifetime significantly under constrains of cost and connectivity.关键词：wirelesssensornetwork;relaynode;artificialbeecolonyoptimization;networklifetime642|1189|0更新时间：2024-06-05
- 摘要：In wireless sensor network,concerning that dramatic changes of speed in a short period of time may lead to angle effect and reduce the location accuracy for tracking,and individual scheme is difficult to improve the location tracking accuracy,a location tracking method using Kalman filter and visual aids on TI CC2431 ZPS platform was proposed.Visual aid was used on the basis of normalized cross correlation,and the position of the reference node was extracted being as landmarks according to the visual aid method,and then the KF method was used to calibrate the position estimation.The proposed method could effectively avoid the uncertainty caused by the system error in the actual dynamic environment,and reduced the angular effect of the position estimation system,and improved the location tracking accuracy.The experimental results demonstrate that more than 56 percent of the location estimates have error distances less than 2.3 meters and 1.9 meters for TI ZPS method and KF based method,more than 56 percent of the location estimates have error distances less than 1.5 meters for the proposed method.关键词：wirelesssensornetwork;locationtracking;Kalmanfilter;visualaid;ZPSplatform425|525|0更新时间：2024-06-05
- 摘要：In OFDM system,sparse channel estimation based on compressed sensing(CS)can make full use of the inherent sparse degree of the wireless channel,which can reduce the pilot overhead and improve the spectrum efficiency.Therefore,a new method based on hybrid genetic algorithm was investigated for the pilot design of CS channel estimation,which was based on the minimization of the matrix cross correlation in the CS theory.In this method,genetic algorithm was used to obtain the initial sub-optimal pilot sequence,and then combined with the pilot position and pilot power,each entry of pilot pattern could be sequentially updated and optimized to make the minimum correlation of measurement matrix.Simulation results show that the proposed method can ensure a better mean square error and bit error rate compared to the pseudo-random pilot design and the equal distance pilot design.关键词：channelestimation;crosscorrelation;hybridgeneticalgorithm;measurementmatrix;compressedsensing,pilotpattern497|957|0更新时间：2024-06-05
- 摘要：The available channel visiting strategy for spectrum handoff mainly considers the probability of handoff failure more than the channel capacity.Aiming at the problem,anovel spectrum suitching channel visiting strategy was proposed based on the probability of handoff failure and the channel capacity foins optimixing of secondary user.It was proved that the maximum channel capacity of secondary user can be obtained by visiting the channel in the descending order of the signal to noise ratio(SNR),and the minimum probability of handoff failure couldbe obtained in the descending order of the mean vacant time duration.Then the mean vacant time of channel and SNR for sorting and weighted combination was processed of non-parameterization.At last,the channel was visited in descending order according to the result of non parametric processing.The numerical results show that the proposed method can increase the channel capacity of secondary user by about 50%,while keeping the probability of handoff failure close to the minimum.关键词：cognitiveradio;spectrumhandoff;channelvisitingstrategy;channelcapacity329|523|0更新时间：2024-06-05
- 摘要：Aiming at the problem that the user’s location privacy may be leaked while users obtain location-based services,mobile terminal and LBS server the ends use k-anonymity mechanisms using the collaborative distributed model.Balanced incremental nearest neighbor (KHINN)query method based on k-anonymity was proposed.When the method structuring anonymous user group in mobile terminal,secure multiparty summation was used to calculate the anchor point to ensure user privacy;when processing the query results,SpaceTwist method based on k-anonymity was used to improve the query privacy and accuracy.Performance analysis and experimental results show that undering the condition of semi trusted or untrusted users between nodes,the proposed method can solve defects of uneven distribution of discovering points around the anchor point in SpaceTwist method and improve the accuracy of the query.关键词：LBSserver;k-anonymous;anchor;querypointofinterest;securesum324|556|0更新时间：2024-06-05
- 摘要：In the test of the actual performance of communication device and software based on meteor burst,a model of meteor burst communication channel was established to solve the complexity of channel and difficulty of measurement.By analyzing the mathematic models of meteor burst channel,single underdense meteor trail channel and single overdense meteor trial channel were modeled as basis.Underdense meteor cluster and multipath channel were proposed to built a hybrid model based on probability principles.Combining with meteor arrival interval model,the simulation of meteor burst channel was realized by C++ programming tool.The simulation result can provide underdense meteor trail,overdense meteor trial,underdense meteor cluster and multipath channel.It indicates that the characteristics of the meteor burst channel model are basically matched with those of real channel.The result verifies usability and justifiability of the model.关键词：meteorburstcommunication;channelmodeling;underdensemeteortrail;overdensemeteortrial;hybridmodel,arrivalinterval666|1114|0更新时间：2024-06-05
- 摘要：An interference source single satellite location method based on movable antenna with spot beam was proposed for GEO satellites.In this method,a mapping relationship between orientation of interference and antenna gain is first established with the function of antenna pattern.Equations were established to calculate the interference signal link combining the orientation information of center of movable spot beam and the intensity of interference signal which derived from moving the beam several times.The orientation of interference was obtained by solving the equations with the help of particle swarm optimization(PSO).Then the longitude and latitude of the interference source could be calculated,jointly considering the ephemeris and the information of the earth.We made a positioning simulation of the ground interference source with the proposed method.The results validate the effectiveness of this method.关键词：interferencesourcelocation;movableantennawithspotbeam;particleswarmoptimization;patternmodel421|868|0更新时间：2024-06-05
- 摘要：A reliability routing protocol based on vehicle density in vehicular Ad Hoc network was proposed to reduce the complexity of finding an optimal or sub-optimal node of the forwarding node in forwarding range,reducing the average number of hops and enhancing the reliability of the link.Firstly,the size of the unite block was set by the forwarding node according to the vehicle density in the road.And the forwarding range was cut into several equal blocks.Then the farthest block away from the forwarding node was selected.In the selected block,the neighbor node which had the longest link time was chosen as a relay node to forward according to the principle of reliability finally.Compared with EG-RAODV,the simulated results of the proposed routing protocol show that the average number of hops is less and the average distance of one-hop progress is lager,which means the proposed routing protocol can transmit the data packet to destination node more quickly.关键词：vehicularAdHocnetwork;routingprotocol;averagenumberofhops;averagedistanceofone-hopprogress283|726|0更新时间：2024-06-05
- 摘要：For the issues that the existing task scheduling scheme based on intelligent algorithms can’t obtain the optimal solution in cloud computing and inspired by nature symbiosis,a new task scheduling scheme based on improved particle swarm optimization(PSO)with biological symbiosis mechanism(SM)was proposed.Firstly,the particles in PSO were divided into two populations,and the optimization process were performed alone.Then,after each execution of the k iteration of PSO,the individual in the two populations performed the mutualism and parasitism operation.The search process was optimized by mutualism operation to through the optimal solution region,which could enhance the search ability.The parasitism operation was used to avoid premature convergence by eliminating the poor and introducing the optimal solution.Finally,the optimal solution of the task scheduling was obtained.Simulation results show that the optimal scheduling scheme can obtain the minimum task completion time and response time.关键词：cloudcomputing;taskscheduling;biologicalsymbiosismechanism;particleswarmoptimization;globalsearchingcapability308|618|0更新时间：2024-06-05
- 摘要：Orthogonal frequency division multiplexing technology is widely used in wireless communication system due to its high spectral efficiency and good resistance ability to frequency selective fading.But it has high peak-to-average power ratio.Therefore,OFDM system needs large input power back-off to avoid signal distortion when using nonlinear power amplifier.In order to study the performance of the system under the condition of nonlinear power amplifier,the implementation of constant envelope OFDM was analyzed.Taking bit error rate as an index,the performance comparison between CE-OFDM system and OFDM system using traditional iterative limiting filter PAPR suppression technology were given under additive white Gaussian noise channel and multipath fading channel.关键词：nonlinearpoweramplifier;constantenvelopeOFDM;PAPR585|828|0更新时间：2024-06-05
Research and Development
- 摘要：The rapid development of cloud computing has recently prompted extensive application of visualization in enterprise-level environments.In addition to server and storage virtualization,network virtualization attracts more and more attention with the application of SDN and OpenFlow.Therewith,software-defined network platforms designed for network virtualization were presented.Firstly,the objectives of the SDN based network virtualization platform were analyzed.Subsequently,the system architectures and principles of four typical network virtualization platforms based on SDN were compared.At last,the safety and isolation mechanism provided by the network virtualization platforms were investigated.关键词：softwaredefinednetworking;networkvirtualization;OpenFlow476|1516|0更新时间：2024-06-05
- 摘要：Based on current situation that PON network faults are mainly processed around the user account password and terminal problems,and all the complex phenomena and network issues involved are sent to the operation and maintenance department,leading to low failure processing efficiency and high treatment pressure,an end-to-end fault diagnosis and repair method was proposed based on the customer resource tree.Through adopting big data analysis technology and service capability opening technology,an end-to-end fault detection system from service platform to client terminals was built and fault phenomena,conclusions and treatment methods of the nodes in the resource tree were combed,and fault processing scenarios were listed to verify the accuracy of fault detection and fast recovery.The result shows that the failure interception efficiency is improved by 34%.关键词：faultdetection;faultdiagnosis;faultrecovery;customerresourcetree386|1454|0更新时间：2024-06-05
- 摘要：Traditional theme mining model generally digs out the document theme from the interactive text only.In order to explore the session topic and improve the universality of mining model,a kind of interactive text session topic generation model based on the content of the dialogue was put forward.Firstly,by analyzing the characteristics of interactive text and based on the concept of topic tree,a dialog spanning tree was defined with a five-layer structure.Based on this and LDA,the model of session topic generation(ST-LDA)was built.At last,Gibbs sampling method was adopted to deduce the ST-LDA and obtaining session topic and its distribution probability.The results show that the ST-LDA model can dig out a session topic effectively from the interactive text.Besides,the results can reduce the complexity of the classification algorithm and can be back to the theme—participants association.It also has a good universality.关键词：interactivetext;conversationcontent;sessiontopicmining;dialogspanningtree;latentDirichletallocation645|2326|0更新时间：2024-06-05
- 摘要：With the bandwidth of private-wire going up,end-to-end cost assessment of large particle private-wire service becomes more important.Based on the end-to-end bearer form and economic evaluation theory,a cost assessment model was presented,and supplemented by case analysis.Main equipment,pipes,cables,equipment room and other costs were takes into account comprehensively.The total annual cost of large particle private-wire service can be accurately evaluated and operators’ pricing can be guided.关键词：end-to-end;WDM;totalannualcost499|758|0更新时间：2024-06-05
- 摘要：With the development of smart grid and the increasing of network application within the electric power information network,electric power CDN plays an important role of network acceleration technology,traffic load balancing and network security.However,facing the rapidly changing of application requirements,electric power CDN was required to response to the application deployment quickly and possess flexible application extensibility.In addition,there are some problems on electric power CDN node expansion,such as complex operations management and low utilization rate of resources.It is necessary to reform the traditional power CDN architecture,SDN and NFV technique can support.The data control can be extracted and transmitted by SDN from the network data,so it is conducive to expand a variety of application in power CDN rapidly.And NFV can expand the CDN node capacity and schedule node resources based on the application.It can effectively reduce the capital ecpenditure,storage and power consumption.关键词：electricpowerCDN;SDN;NFV;expansionofnetworkapplication;operationmanagement470|1280|0更新时间：2024-06-05
- 摘要：Due to the harsh usage environment,embedded SIM(eSIM)card are required,and its remote provisioning is needed correspondingly.Business requirements and technological development of eSIM were analyzed.The technical architecture and business mode of remote provisioning for eSIM were also discussed.关键词：eSIM;internetofvehiclesnetwork;OTA808|4036|0更新时间：2024-06-05
- 摘要：Network virtualization aims to realize the decoupling of hardware and software by virtualization,and share the resource according to service size by cloudification,thus supporting the telecom business with features of high flexibility,maintainability,usability and immediate return of investment.The virtualization architecture and key technologies of NFV were introduced,and the typical NFV application scenarios for telecom operators were presented to promote the research and implementation of telecom network virtualization technology.关键词：NFV;keytechnology;applicationscenario657|1620|0更新时间：2024-06-05
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