最新刊期
卷 35 ， 期 1 ， 2019
- 摘要：With the Ministry of Industry and Information Technology announcing that it has issued a test frequency license to China Telecom, China Mobile and China Unicom for the low and medium frequency band of the 5G mobile communication system, China's 5G commercial pace has officially begun. The global deployment, commercial situation and the oriented industrial network characteristics of 5G were introduced. It was pointed out that 5G would continue to consolidate the foundation for interconnectivity of all things, fully enable the industrial internet, and accelerate the integration of multi-industry internet.关键词：5G;telecom operator;industrial Internet;artificial intelligence;big data;cloud computing;Internet of things427|958|0更新时间：2024-06-05
Viewpoint focus
- 摘要：A new Android malware detection method based on byte-code image and deep learning was proposed. Firstly, Android malware byte-code files were mapped to RGB colorful images which had three channels. Also, the Shannon entropy as Alpha channel of images were calculated, and then merged with RGB images into RGBA images. Finally, the convolutional neural network as classifier was employed to classify aforementioned images. According to the experiment on malware of eight malicious families and compared this method with the method which mapping the byte-code to gray image, the result shows that the method using RGBA images has good performance not only in speed, but also in accuracy.关键词：malware detection;byte-code image;Shannon entropy;deep learning;classification482|746|0更新时间：2024-06-05
- 摘要：To improve the users' satisfaction of download files, a caching based resource allocation algorithm in energy-harvesting small cell networks was proposed, which was established as a Stackelberg game that jointly optimized user accessing and small cells' content updating. Firstly, a coalitonal game for users to transfer between coalitions (small cells) with user satisfaction being utility function was proposed, and the transition was accepted once the utility of user after transferring satisfies the transition rules. Several users were allowed to be served by a same cell, and users accessing the same small cell would share the same channel using NOMA. Then, to maximize the benefit, a cache updating scheme was put forward to update the files cached by small cells. The equilibrium solution could be achieved after finite iterations of the two algorithms. The simulation results show that the proposed novel algorithm performs better in user satisfaction and energy-saving comparing with algorithm using principle of proximity.关键词：coalitonal game;content caching;energy-harvesting;NOMA410|307|0更新时间：2024-06-05
- 摘要：A method of broadband power line communication (PLC) channel modeling based on Q3D extractor was proposed. The per unit length RLGC parameters of PLC channel was extracted by the Q3D extractor. Then, the ABCD transfer matrix of power line channel was calculated based on the extracted RLGC parameters. Finally, the amplitude and phase frequency responses of the channel transfer function and input impedance were obtained by using ABCD matrix. Based on the proposed method, a broadband PLC channel model for 3 mm×4 mm symmetrical cable was set up. The calculated results show that the simulated results fit the measured results well. The proposed method can quickly and accurately establish the broadband PLC channel model, which is of great significance for studying the characteristics of PLC channel.关键词：power line communication;broadband;channel model;Q3D;three cores symmetrical cable95|289|0更新时间：2024-06-05
- 摘要：In the parameter estimation of the sensor network, there may be impact noise or pulse interference in the measurement environment, which leads to the outliers that greatly deviate from the actual range, so that the effective parameter estimation problem can't be obtained. A distributed RLS estimation algorithm based on node cooperation and robustness was proposed. The characteristic of interference or attack on a node is usually sporadic (ie, sparse) for a period of time was utilized, ℓ1norm was introduced to cost function. The outliers which may exist in the measurement data were identified and eliminated, and the interaction between the nodes of the network was utilized to further improve the performance of the parameter estimation. The computer simulation experiments show that the algorithm has good estimation performance.关键词：sensor network;robustness;distributed processing;adaptive estimation47|260|0更新时间：2024-06-05
- 摘要：In consideration of the issues of the survival time of node, the uncertainness of channel state information and the poor quality of the service in underwater acoustic cooperative communication network, a robust power allocation algorithm was proposed. Firstly, the residual energy of node was considered in the optimization function, and the change of transmitted power was proportional to the remaining energy, thereby balancing the energy consumption and increasing the survival time of the nodes. Secondly, the uncertainty was further introduced into the optimization function to improve the ability of against uncertainty in underwater. At the same time, in order to make sure that the quality of the service, the minimum communication capacity requirements were considered in the optimization function. The simulation results show that the proposed algorithm not only extends the survival time of node, but also improves the performance of system.关键词：underwater communication;cooperative communication;power allocation;survival time87|229|0更新时间：2024-06-05
- 摘要：In order to reasonably evaluate the vulnerability of the power communication network link, a vulnerability assessment method based on the mechanical model was proposed. The bandwidth capacity occupied by the traffic on the link and the number of inter-node services were collectively referred to as nodes. The correlation between the links and the degree of correlation between the link services was regarded as an associated generalized business force. In the process of business statistics, the maximum likelihood estimation of the time-slotted time slot was adopted, and the parameters of the service were estimated by using the Poisson process as a statistical background. The number of services between links and the occupied bandwidth were regarded as work of generalized service. The logical distance of the links between nodes was obtained by the gravitational formula, and the vulnerability of the communication network was measured by the interval of logical distance. Finally, MATLAB was used to establish a model for simulation calculation, it is verified that the method can analyze and evaluate the vulnerability of the service link of the power communication network in real time and accurately.关键词：vulnerability;communication network;topological structure;link service;mechanical model40|180|0更新时间：2024-06-05
- 摘要：A novel cooperative location method based on time-of-arrival in wireless senor networks was proposed. Firstly, the optimization problem for the target location was established. Secondly, the mixed semi-positive definite and second-order cone relaxation techniques were used to convert the original non-convex problem into a convex optimization problem. In this way, a fast suboptimal solution to the original problem was obtained. Finally, computer simulations show that the proposed method has lower root mean square error (RMSE) which is closer to the Cramer-Rao lower bound (CRB).关键词：time-of-arrival;cooperative localization;mixed semi-positive definite and second-order cone relaxation;Cramer-Rao bound88|253|0更新时间：2024-06-05
- 摘要：According to the problem of poor sensing performance caused by the existing spectrum sensing algorithm, the covariance matrix opportunistic cooperative (CMOC) spectrum sensing algorithm was proposed. Based on the traditional covariance matrix spectrum sensing algorithm, odd and even slots were divided by the new proposed algorithm, then opportunistic cooperation was added. The relationship between the false alarm probability and the threshold of the new algorithm was also analyzed, and the analytic detection probability was deduced for the actualization of the more accurate spectrum sensing detection. The simulation results verify that the proposed algorithm obviously improves the detection probability. In Rayleigh fading channel, the detection probability is increased by 0.19 and 0.13, which compared with the existing energy detection spectrum sensing algorithm without relay cooperative and the covariance matrix spectrum sensing algorithm without relay cooperation, when the SNR is −10 dB. Moreover, the proposed algorithm has high energy efficiency as well as the moderate computational complexity, so it is especially suited for the spectrum cognition applications in the new generation wireless communication.关键词：spectrum sensing;covariance matrix;opportunistic cooperative;threshold value66|189|0更新时间：2024-06-05
- 摘要：A novel Kalman prediction and compressed sensing based energy-efficient data gathering scheme was proposed. Specially, in the intra-cluster transmission, the cluster members utilized the Kalman prediction to selectively send the data to their cluster heads. In the inter-cluster transmission, the cluster heads leveraged the hybrid compressed sensing to transfer the data to the sink via multi-hop links. Moreover, the communication cost was derived to verify the efficiency of the proposed method. Simulation results show that the proposed method has higher energy efficiency compared with the available schemes, and the sink can obtain measurements with reasonable quality by using the proposed method.关键词：wireless sensor network;Kalman prediction;compressed sensing;spatial-temporal correlation;energy efficiency56|170|0更新时间：2024-06-05
- 摘要：With the increasing concern of machine learning security issues, an adversarial sample generation method for SVM was proposed. This attack occurred in the testing stage by manipulating with the sample tofool the SVM classification model. Greedy strategy was used to search for salient feature subsets in kernel space and then the perturbation in the kernel space was projected back into the input space to obtain attack samples. This method made the test samples misclassified by less than 7% perturbation. Experiments are carried out on two data sets, and both of them are successful. In the artificial data set, the classification error rate is above 50% under 2% perturbation. In MNIST data set, the classification error rate is close to 100% under 5% perturbation.关键词：machine learning;support vector machine;greedy algorithm;salient feature;adversarial sample42|170|0更新时间：2024-06-05
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Quantitative analysis of the influence of asymmetric channel delay on relay protection's reliability
摘要：The asymmetric delay of digital channels has negative effects on line current differential protection in a complex mechanism. Hence, it's necessary to use effective methods to improve the reliability of relay protection. Firstly, the operation principle and criterion of line current differential protection were analyzed.Then, the influence of asymmetric delay on the reliability of relay protection was analyzed, and the quantitative analysis method of the influence under different fault conditions was determined. Finally, the feasibility and correctness of the method were verified. The results show that effects of asymmetric delay on reliability of relay protection have a significant correlation with fault conditions. This conclusion has practical value in reliability evaluation and channel optimization of relay protection.关键词：line current differential protection;relay protection channel;asymmetric delay;reliability of relay protection;simulation analysis57|443|0更新时间：2024-06-05
Research and development
- 摘要：Network function virtualization (NFV) is a kind of new network technology rising in recent years. It realizes the decoupling of software and hardware by running the software which has specific function on a general-purpose hardware server. Applying the NFV to the radio access network could virtualize some of the radio access functions. It can reduce the operating costs and capital costs efficiently, and improve the flexibility of the network deployment. It also can satisfy the quality of experience of mobile users. In order to review the work that contribute to the current situation of NFV in radio access network, three perspectives were reviewed, including research on the related standards of network functional virtualization in RAN, network architecture of network function virtualization, and the resource allocation of network function deployment. Finally, the challenges of network function virtualization applying in wireless network were proposed.关键词：network function virtualization;resource allocation;radio access network146|620|0更新时间：2024-06-05
Overview
- 摘要：For the near space high altitude platform station (HAPS), its limited power, tight spectrum resources, and the multipath fading effects due to non line of sight (NLoS) and low elevation communication environment are the main problems. An anti-fading technology of near space communication based on quasi-constant envelope OFDM (QCE-OFDM) was proposed. At the transmitting end, two OFDM signals were respectively modulated on the phases of two constant envelope signals, and then they were merged into one signal via phase shift. At the receiving end, Taylor series expansion technology was employed to divide and demodulate the signal. Analysis and simulation results show that the QCE-OFDM has the same spectral efficiency as OFDM. By selecting the modulation index reasonably, the proposed scheme can combat multipath fading effectively with less than 3 dB signal peak-to-average power ratio (PAPR), where the goal of high spectral efficiency and high energy efficiency can be achieved.关键词：near space communication;high altitude platform station;quasi-constant envelope;orthogonal frequency division multiplexing;multipath fading;peak-to-average power ratio60|212|0更新时间：2024-06-05
- 摘要：In the communication system, limited by the influence of channel correlation, in general, the lower the operating frequency band of the antenna system, the larger the spacing of the antenna elements, and the larger spacing of the array elements was not conducive to the reduction of the physical size of the communication device. An antenna system with an array spacing was analyzed, which could achieve a smaller physical size than an antenna system with a conventional array spacing. Three kinds of transmit antenna systems were selected for performance comparison: 8-antenna λ /2 system, 4-antenna λ /2 system (of comparable size), and 8-antenna λ /2 system (with the same number of elements). Also their beamforming effect, interference suppression capability and channel capacity were analyzed. Simulation results show that the antenna system can achieve relatively good performance.关键词：low-band communication system;element spacing;precoding41|183|0更新时间：2024-06-05
- 摘要：The top-level design of the intelligent city constructed on provincial CATV networks was mainly investigated. The general thoughts of the development of intelligent city constructed on CATV networks were proposed, and the overall framework for the intelligent city constructed on CATV networks was analyzed.关键词：provincial CATV network;intelligent city;top-level design42|340|0更新时间：2024-06-05
- 摘要：Since the combination of device-to-device (D2D) and mmWave technology can meet the needs of large-capacity, resource allocation was considered for D2D users in an outdoor millimeter wave scenario. The optimal objective was maximize to the total system throughput. Firstly, the admission set of each D2D user was selected by a linear correlation method. Then, power control was performed on the D2D user to select the optimal transmit power. Finally, a multi-phase matching algorithm based on bipartite graph was proposed to allocate resources for D2D users, and the allocation result was obtained by using multiple KM algorithms. The simulation results show that the proposed algorithm is superior to the comparison algorithm, which effectively improves the throughput of the system and spectrum utilization.关键词：device-to-device;millimeter wave;resource allocation;throughput58|135|0更新时间：2024-06-05
- 摘要：The 3GPP's VoWi-Fi S2b specification requires the client to use the IPSec tunnel to register with the ePDG through the metropolitan area network. When IPSec faces a path forwarding fault in a multi-equivalent path environment of a metropolitan area network, it can't actively evade, and the service can't be registered. The cause of the malfunction was analyzed and an optimized solution was proposed. By changing the client source port in the IKE_AUTH phase to achieve path replacement, the VoWi-Fi registration success rate can be significantly improved and verified by experiments. Secondly, through the full traversal detection of the bidirectional network path between the edge of the metropolitan area network and the ePDG end, the fault can be quickly located and eliminated.关键词：VoWi-Fi;KE;IPSec;3GPP R10;ECMP58|176|0更新时间：2024-06-05
- 摘要：With the expansion of the power grid and the increase of the complexity of the power system, the power grid has more stringent requirements for the security of the services transmission. In the secondary protection system of power systems, traditional encryption devices use symmetric encryption algorithms to add and decrypt communication data. Quantum keys have extremely high security. Applying the quantum keys to the power communication network encryption devices can greatly improve the security of service transmission. The quantum key resources generated by the existing quantum key distribution devices is limited, and it is difficult to ensure that all power services data are encrypted and transmitted. Therefore, it is necessary to prioritize the confidential transmission of important services by establishing appropriate evaluation methods for services importance. A relative importance matrix based on the transmission performance indicators of each service was built under the background of quantum communication, so as to obtain the importance of the power communication network business, and to carry out subsequent quantum key application strategy research.关键词：electric power communication network;secondary protection system of power system;quantum key;service importance evaluation74|244|0更新时间：2024-06-05
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