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Multiuser beamforming based on max SINR for downlink spatial multiplexing MIMO

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The Journal of China Universities of Posts and telecommunications 2007年第3期14卷 28-33页

作者： MA Peng-fei ZHENG Kan WANG Wen-bo Wireless Signal Processing and network Laboratory Beijing University ofPosts and Telecommunications Beijing 100876 China

In this article, a method based on max signal interference noise ratio（SINR） criterion is proposed, to mitigate the interuser interference for downlink multiuser spatial multiplexing multi-input multi-output（MIMO） systems. Unlike the zero forcing （ZF） scheme in which the SNR is decreased when the interference is eliminated completely, max SINR method makes a compromise between noise and interuser interference. When the number of substreams is larger than the difference between the number of base station antennas and the sum of interference mobile station antennas, the ZF is infeasible An existing coordinated TX-RX block diagonalization（COOR BD） method uses preprocessing at the receiver to cancel the interuser interference. However, it cannot obtain more receive diversity gain because of the preprocessing. Analysis and simulation show that the max SINR scheme has better performance than the ZF method. Moreover, when the ZF is infeasible, the max SINR scheme can obtain more receive diversity gain than COOR BD in the two-user case.

关键词： array signal processing beamforming MIMO systems spatial multiplexing

Distributed secure quantum machine learning

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Science Bulletin 2017年第14期62卷 1025-1029页

作者： Yu-Bo Sheng Lan Zhou Key Laboratory of Broadband Wireless Communication and Sensor network Technology Nanjing University of Posts and Telecommunications Ministry of Education College of Mathematics & Physics Nanjing University of Posts and Telecommunications

Distributed secure quantum machine learning （DSQML） enables a classical client with little quantum technology to delegate a remote quantum machine learning to the quantum server with the privacy data preserved. Moreover, DSQML can be extended to a more general case that the client does not have enough data, and resorts both the remote quantum server and remote databases to perform the secure machi~ learning. Here we propose a DSQML protocol that the client can classify two-dimensional vectors to dif- ferent clusters, resorting to a remote small-scale photon quantum computation processor. The protocol is secure without leaking any relevant information to the Eve. Any eavesdropper who attempts to intercept and disturb the learning process can be noticed. In principle, this protocol can be used to classify high dimensional vectors and may provide a new viewpoint and application for future ＂big data＂.

关键词： Quantum machine learning Quantum communication Quantum computation Big data

Measurement methods on the complexity of network

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Journal of Harbin Institute of Technology(New Series) 2010年第4期17卷 540-547页

作者：林琳丁刚陈国松 dept.of Mechanical Engineering Harbin Institute of Technology

Based on the size of network and the number of paths in the network,we proposed a model of topology complexity of a network to measure the topology complexity of the network. Based on the analyses of the effects of the number of the equipment,the types of equipment and the processing time of the node on the complexity of the network with the equipment-constrained,a complexity model of equipment-constrained network was constructed to measure the integrated complexity of the equipment-constrained network. The algorithms for the two models were also developed. An automatic generator of the random single label network was developed to test the models. The results show that the models can correctly evaluate the topology complexity and the integrated complexity of the networks.

关键词： network complexity equipment-constraint

Off-Grid Compressed Channel Estimation with Parallel Interference Cancellation for Millimeter Wave Massive MIMO

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China Communications 2024年第3期21卷 51-65页

作者： Liu Jinru Tian Yongqing Liu Danpu Zhang Zhilong Beijing Laboratory of Advanced Information network Beijing Key Laboratory of Network System Architecture and ConvergenceBeijing University of Posts and TelecommunicationsBeijing100876China

Millimeter wave(mmWave)massive multiple-input multiple-output(MIMO)plays an important role in the fifth-generation(5G)mobile communications and beyond wireless communication systems owing to its potential of high ***,channel estimation has become very challenging due to the use of massive MIMO antenna ***,the mmWave channel has strong sparsity in the spatial angle domain,and the compressed sensing technology can be used to convert the original channel matrix into the sparse matrix of discrete angle *** the high-dimensional channel matrix estimation is transformed into a sparse recovery problem with greatly reduced computational ***,the path angle in the actual scene appears randomly and is unlikely to be completely located on the quantization angle grid,thus leading to the problem of power ***,multiple paths with the random distribution of angles will bring about serious interpath interference and further deteriorate the performance of channel *** address these off-grid issues,we propose a parallel interference cancellation assisted multi-grid matching pursuit(PIC-MGMP)algorithm in this *** proposed algorithm consists of three stages,including coarse estimation,refined estimation,and inter-path cyclic iterative inter-ference *** specifically,the angular resolution can be improved by locally refining the grid to reduce power leakage,while the inter-path interference is eliminated by parallel interference cancellation(PIC),and the two together improve the estimation *** results show that compared with the traditional orthogonal matching pursuit(OMP)algorithm,the normalized mean square error(NMSE)of the proposed algorithm decreases by over 14dB in the case of 2 paths.

关键词： channel estimation compressed sensing inter-path interference millimeter wave massive MIMO off-grid parallel interference cancellation

Event-trigger-based consensus secure control of linear multi-agent systems under DoS attacks over multiple transmission channels

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Science China(Information Sciences) 2020年第5期63卷 105-118页

作者： Yang YANG Yanfei LI Dong YUE College of Automation & College of Artificial Intelligence Nanjing University of Posts and Telecommunications Jiangsu Engineering Laboratory of Big Data Analysis and Control for Active Distribution network Nanjing University of Posts and Telecommunications Institute of Advanced Technology Nanjing University of Posts and Telecommunications

This paper proposes a consensus secure control scheme in the presence of denial-of-service(DoS)attacks based on an event-trigger mechanism. In contrast to a scenario in which attacks are the same and simultaneously paralyze all channels, the DoS attack addressed in this paper occurs aperiodically and results in the independent interruption of multiple transmission channels. A sufficient condition for the attack duration is designed and a distributed event-triggered control scheme is proposed, where the updated instants are triggered aperiodically to reduce the required communication resources. It is shown that the overall system is stable with the proposed scheme according to the Lyapunov stability theory and that Zeno behavior is excluded. Finally, a numerical example is presented to verify the effectiveness of the proposed scheme.

关键词： multi-agent system event-triggered control consensus secure control denial-of-service attack multiple transmission channels

Improvement of LDA model with time factor for collaborative filtering

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The Journal of China Universities of Posts and telecommunications 2019年第6期26卷 54-62页

作者： Yao Wenbin Hu Fangyi Beijing Key Laboratory of Intelligent telecommunications Software and Multimedia Beijing University of Posts and TelecommunicationsBeijing 100876China National Engineering Laboratory for Mobile network Beijing University of Posts and TelecommunicationsBeijing 100876China

Collaborative filtering(CF) is one of the most widely used Algorithm in recommender systems, which help users obtain the information they may like. We proposed a latent Dirichlet allocation(LDA) model combining time and rating(TR-LDA) for CF. We use mathematical methods to fit the Ebbinghaus forgetting curve in our method and introduce time weights based on time window to find out the impact of time on user’s interests. The user’s choice of items is not only influenced by his/her interests, but also influenced by other’s rating. According to the users’ feedback, we find their rating distribution on items under the interests. Finally, experimental results on real data sets MovieLens 100 k and MovieLens 1 M show that the proposed Algorithm can predict the user implicit interests effectively and improve the recommendation performance.

关键词： CF LDA forgetting curve time window feedback

Graph theory based physical cell identity self-configuration for LTE-A network

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The Journal of China Universities of Posts and telecommunications 2013年第1期20卷 101-107页

作者： WEI Yao WANG Wen-bo PENG Mu-gen MIN Shi-jun Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Wireless Signal Processing and network Laboratory Beijing University of Posts and Telecommunications

Self-configuration of physical cell identity （PCI） is a key feature for the long term evolution advanced （LTE-A） network. The PCI is used to identify the different cells in the system, becoming an essential cell configuration parameter. Considering the uncoordinated deployments of the evolved Node B （eNodeB） and the limited number of PCI, the PCI assignment for cells would be quite complex. This paper presents and puts forward a graph theory based centralized PCI self-configuration scheme （GT-PCIS）. The PCI self-configuration problem is mapped to the well-known minimum spanning tree （MST） problem in order to optimize the PCI reuse distance and decrease the multiplexing interference throughout the entire network. The proposal provides a greedy search to make the locally optimal selection of PCI at each stage, and to achieve a global optimum. To demonstrate the algorithm validity, performances of GT-PCIS and manual configuration are evaluated. Simulation results show that the proposed GT-PCIS outperforms other configuration algorithms even under the condition of severe PCI deficiency.

关键词： LTE-A PCI MST self-configuration

Multiple CRC-aided variable successive cancellation list decoder of polar codes

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The Journal of China Universities of Posts and telecommunications 2017年第2期24卷 83-88页

作者： Cao Miao Zhao Shuang Zhao Shengmei Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Key Laboratory of Broadband Wireless Communication and Sensor network Technology Nanjing University of Posts and Telecommunications

In order to change the path candidates, reduce the average list size, and make more paths pass cyclic redundancy check （CRC）, multiple CRC-aided variable successive cancellation list （SCL） decoding algorithm is proposed. In the decoding algorithm, the whole unfrozen bits are divided into several parts and each part is concatenated with a corresponding CRC code, except the last part which is concatenated with a whole unfrozen CRC code. Each CRC detection is performed, and only those satisfying each part CRC become the path candidates. A variable list is setup for each part to reduce the time complexity. Variable list size is setup for each part to reduce the time complexity until one survival path in each part can pass its corresponding CRC. The results show that the proposed algorithm can reduce the average list size, and the frame error rate （FER） performance, and has a better performance with the increase of the part number.

关键词： polar codes successive cancellation list decoder cyclic redundancy check list path variable list size

Joint system consumption minimization and workload allocation in edge-core network

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The Journal of China Universities of Posts and telecommunications 2018年第3期25卷 45-54页

作者： Wang Shaochun Lu Zhaoming Wen Xiangming Wang Luhan Ma Lu Beijing Laboratory of Advanced Information networks Beijing University of Posts and Telecommunications Beijing Key Laboratory of network System Architecture and Convergence Beijing University of Posts and Telecommunications

The explosive increase of smart devices and mobile traffic results intolerable network latency and degraded service to the end-users. in heavy burden on backhaul and core network, As a complement to core network, edge network contributes to relieving network burden and improving user experience. To investigate the problem of optimizing the total consumption in an edge-core network, the system consumption minimization problem is fromulated, considering the energy consumption and delay. Given that the formulated problem is a mixed nonlinear integer programming （MNIP） , a low-complexity workload allocation algorithm is proposed based on interior-point method. The proposed algorithm has an extremely short running time in practice. Finally, simulation results show that edge network can significantly complement core network with much reduced backhaul energy consumption and delay.

关键词： edge network core network system consumption optimization workload allocation