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Broadband hybrid model for relay-aided cooperative MIMO power line communication systems

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The Journal of China Universities of Posts and Telecommunications 2020年第1期27卷 72-80页

作者： liang xiaolin Cao Wangbin School of Electronic and Information Engineering Hebei UniversityBaoding 071002China School of Electrical and Electronic Engineering North China Electric Power UniversityBaoding 071000China

A hybrid model for broadband multiple-input multiple-output(MIMO) relay-aided indoor power line communications(PLC) system was proposed in this paper. The proposed model combines the top-down and bottom-up approaches and extends to a two-hop relay-aided cooperative system with variable gain relay in amplify-and-forward(AF) mode. Based on the proposed PLC model and generated channel, the channel statistical characteristics are further investigated in 2 MHz^100 MHz bandwidth. Simulated results show that the proposed model overcomes the difficulties that the existing models need a lot of topological information of the network or measurements information. It provides a practical simulation analysis method for cooperative relay MIMO-PLC system. The results also show that cooperative MIMO relaying communications can improve the indoor PLC performances and communication reliability.

关键词： broadband communication channel frequency response(CFR) hybrid model MIMO-PLC power line communications(PLC) relay-aided

Modeling and realization of mobile-to-mobile wideband MIMO channels based on the geometrical multi-ring and multi-ellipse stochastic scattering model

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The Journal of China Universities of Posts and Telecommunications 2018年第5期25卷 39-48页

作者： liang xiaolin Cao Wangbin Zhao Xiongwen School of Electronic and Information Engineering Hebei UniversityBaoding 071002 China School of Electrical and Electronic Engineering North China Electric Power University Baoding 071000 China School of Electrical and Electronic Engineering North China Electric Power University Beijing 102206 China

A geometry-based stochastic scattering model （GBSSM） based on geometrical multiple rings and ellipses is proposed for wideband multiple-input multiple-output （MIMO） mobile-to-mobile （M2M） fading channels. The proposed GBSSM is deployed with cross-polarized antennas and can be applied for the line-of-sight （LOS） and non- LOS （NLOS） scenarios by considering the single-bounced （SB） and double-bounced （DB） components. The channel realization is much more straightforward and concise to study the channel characteristics compared with the too complicated analytical solutions available so far. Based on the proposed GBSSM and realized channel, the channel characteristics and parameters at 2 GHz and 5 GHz with 100 MHz bandwidth are further investigated. The results can be used in the link and system level simulations in M2M radio systems.

关键词： cross-polarized antennas mobile-to-mobile multiple-input multiple-output multl-rlng and multi-ellipse wideband channels

NLOS Identification and Machine Learning Methods for Predicting the Outcome of 60GHz Ranging System

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Chinese Journal of Electronics 2018年第1期27卷 175-182页

作者： liang xiaolin JIN Yiheng ZHANG Hao LYU Tingting College of Information Science and Engineering Ocean University of China Department of Electrical Computer Engineering University of Victoria

Millimeter-wave(MMW) signals in 60 GHz band have shown immense potential for accurate range estimation with precise time and multipath resolution. Nonline of sight(NLOS) propagation is a primary factor affecting the range precision. To improve range estimation,an Energy detector(ED) based normalized threshold algorithm which employs a Neural network(NN) is developed on the basis of NLOS identification. The maximum curl and standard deviation of the received energy block values are used to determine NLOS environment and the normalized thresholds for different Signal-to-noise ratios(SNRs). The effects of the channel and integration period are *** results are presented which show that the proposed approach provides better precision and is more robust than other solutions over a wide range of SNRs for the CM1.1 and CM2.1 channel models in the IEEE802.15.3 c standard.

关键词： Non-line of sight(NLOS) identification Curl Standard deviation IEEE 802.15.3c Machine learning

Coercivity Enhancement of the Sintered Nd-Fe-B Magnet with Intergranular Multi-Addition

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Wuhan University Journal of Natural Sciences 2016年第2期21卷 165-170页

作者： liang xiaolin YAN Gaolin School of Physics and Technology Wuhan University

In order to improve the coercivity of the sintered Nd-Fe-B magnet,a Nd13.5Fe79.75B6.75magnet with intergranular multi-addition of 2%Dy H3,2%Nd H3and 1%Nd2O3is prepared and its magnetic property and microstructure are *** results show that the coercivity of the magnet with multi-addition is as high as 1 300 k A/m,while that of the magnets with Dy H3and Nd2O3are 520 k A/m and 850 k A/m,*** electron microscope（SEM）shows that the grain boundaries in the magnet with multi-addition are smoother and the grain size is smaller than that in the magnet without the *** with addition of Dy H3or Nd2O3,the multi-addition can more effectively enhance coercivity of the *** adding process with multi-addition can both increase the anisotropy field and optimize the grain-boundary microstructure of the *** a result,the coercivity of the magnet is significantly increased.

关键词： rare earth permanent magnet coercivity intergranular adding process

Magnetic Properties and Thermal Stability of Sintered Nd-Fe-B Magnet with Dy-Ni Additive

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Wuhan University Journal of Natural Sciences 2016年第4期21卷 339-343页

作者： liang xiaolin YAN Gaolin School of Physics and Technology Wuhan University

A sintered（Nd_（0.8）Pr_（0.2））_（30.7）FebalB_（0.98）Cu_（0.2） magnet with 3% intergranular Dy_（85）Ni_（15） additive is prepared to study the magnetic properties and thermal stability of the Nd-Fe-B magnet. The results show that the magnet with or without additive obtains its optimum comprehensive magnetic properties at the sintering temperature of 1 030 ℃ and 1 040 ℃, respectively. The maximum coercivity of the magnet with additive reaches 15.16 k Oe, while that of the magnet without additive is just 11.88 k Oe. Further investigation on microstructure indicates that the grains of the magnet with additive form a modified ＂core shell＂ structure. Adding Dy_（85）Ni_（15） can significantly enhance the coercivity of Nd-Fe-B magnet and thus decrease its coercivity temperature coefficient.

关键词： rare earth magnet sintering temperature thermal stability coercivity

Modeling and analysis of actively Q-switched Fe:ZnSe laser pumped by a 2.8μm fiber laser

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Optoelectronics Letters 2023年第9期19卷 513-518页

作者： liang xiaolin ZHOU Songqing LIU Zhizhuang BAO Bengang College of Intelligent Manufacturing Hunan University of Science and EngineeringYongzhou 425199China

A theoretical model concerning active Q-switching of an Fe:ZnSe laser pumped by a continuous-wave(CW)2.8μm fiber laser is *** are compared with the recently reported experiment results,and good agreement is *** of principal parameters,including pump power,output reflectivity,ion concentration and temperature of crystal,on the laser output performance are investigated and *** results demonstrate that similar to highly efficient CWFe:ZnSe laser,low temperature of the crystal is significant to obtain high peak power Q-switched *** numerical simulation results are useful for optimizing the design of actively Q-switched Fe:ZnSe laser.

关键词： Modeling and analysis of actively Q-switched Fe:ZnSe laser pumped by a 2.8μm fiber laser

A Precoding Scheme to Reduce the Effect of Channel Correlation for MIMO-PLC System

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China Communications 2023年第2期20卷 216-225页

作者： Wangbin Cao Hui Kang xiaolin liang Zhiyuan Xie Xiongwen Zhao School of Electrical and Electronic Engineering North China Electric Power UniversityBaoding 071000/Beijing 102206China School of Electronic and Information Engineering Hebei UniversityBaoding 071002China Hebei Key Laboratory of Power Internet of Things Technology(North China Electric Power University) Baoding 071003China

MIMO technique can provide higher information throughput and transmission reliability for the PLC ***,the MIMO-PLC system based on three-conductor cable has a high correlation among its *** multiplexing technology will be affected by the spatial correlation between MIMO-PLC *** reduce the system bit error rate caused by MIMO-PLC correlation among sub-channels,this paper proposed a phase rotation precoding scheme for the 2×2 closed-loop MIMO-PLC *** to the channel transfer function of high correlation MIMO-PLC system,the phase rotation precoding matrix F is calculated,and the transmission signal matrix S is modulated with the F,the code distance at the receiving point with smallest code distance is increased by phase *** results show that the scheme can effectively reduce the bit error rate of the 2×2 MIMO-PLC system based on ML detection,and significantly improve the system performance.

关键词： carrier transmission on power lines telecommunication cables error correction precoding

Performance analysis of different coding schemes for wideband vehicle-to-vehicle MIMO systems

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The Journal of China Universities of Posts and Telecommunications 2023年第6期30卷 89-98页

作者： liang xiaolin Rong Zhanyi Cao Wangbin Liu Shuaiqi Zhao Xiongwen College of Electronic and Information Engineering Hebei UniversityBaoding 071002China Hebei Key Laboratory of Power Internet of Things Technology North China Electric Power UniversityBaoding 071003China School of Electrical and Electronic Engineering North China Electric Power UniversityBaoding 071003China School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China

The signal is subjected to lots of interferences in vehicle-to-vehicle(V2V)channel propagation,resulting in receiving error ***-dimensional(2D)and three-dimensional(3D)geometrical channel models are used to depict the wideband V2V multiple-input multiple-output(MIMO)*** the channel model,Turbo code and low-density parity-check(LDPC)code are investigated for wideband V2V MIMO system,and the encoding and the decoding schemes are *** bit error rate(BER),channel capacity and outage probability of wideband V2V MIMO system using Turbo code and LDPC code are analyzed at different typical *** results show that the performance of wideband V2V MIMO system using Turbo code outperform that using LDPC *** performance is affected by transmitting and receiving speeds with the same coding *** the channel capacity of the 3D channel is larger than that of 2D channel.

关键词： geometrical channel models Turbo code low-density parity-check(LDPC)code vehicle-to-vehicle(V2V)communication wideband channels

A 3D Geometry-Based Scattering Model for Vehicleto-Vehicle Wideband MIMO Relay-Based Cooperative Channels

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China Communications 2016年第10期13卷 1-10页

作者： xiaolin liang Xiongwen Zhao Shu Li Qi Wang Wenbing Lu School of Electrical and Electronic Engineering North China Electric Power University National Mobile Communications Research Laboratory Southeast University

In this paper, a three-dimensional(3D) geometry- based stochastic scattering model(GBSSM) for wideband multi-input multi-output(MIMO) vehicle-to-vehicle(V2V) relay-based cooperative fading channel based on geometrical three-cylinder is proposed. Non-line-of-sight(NLOS) propagation condition is assumed in amplify-and-forward(AF) cooperative networks from the source mobile station(S) to the destination mobile station(D) via the mobile relay station(R). We extend the proposed narrowband model to wideband and also introduce the carrier frequency and bandwidth into the model. To avoid complicated procedure in deriving the analytical expressions of the channel parameters and functions, the channel is realized first. By using the realized channel matrix, the channel properties are further investigated.

关键词： geometry-based scattering model MIMO relay-based cooperative communication vehicle-to-vehicle(V2V) wideband