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China Communications 2020年第12期17卷 52-65页

作者： Zhiang Niu Wenyuan Ma Wei Wang Tao Jiang Wuhan National Laboratory for Optoelectronics and School of Electronic Information and Communications Huazhong University of Science and TechnologyWuhan 430074China

Ambient backscatter communications(AmBC)is a new ultra-low-power communication paradigm,which holds great promise for enabling energy self-sustainability(ESS)to massive data-intensive Internet of Everything(IoE)devices in *** advances improve throughput and reliability by adopting multiple-antenna techniques in conventional backscatter communications(CoBC),but they cannot be directly applied to AmBC devices for high spectral and energy efficiency due to the unknown RF source and minimalist design in backscatter *** fill this gap,we propose SM-backscatter,an AmBC-compatible system that greatly improves spectral efficiency while maintaining ultra-low-power ***,the SM-backscatter consists of two novel components:i)a multiple-antenna backscatter tag that adopts spatial modulation(SM),and ii)a joint detection algorithm that detects both backscatter and source *** this end,we theoretically obtain an optimal detector and propose two suboptimal detectors with low ***,we derive the BERs of both the backscatter and source signals to analyze the communication performance by introducing a two-step *** simulation results verify the correctness of the theoretical analysis and indicate that our system can significantly outperform existing solutions.

关键词： ambient backscatter communications spatial modulation joint detector union bounding technique

Physical-Layer Encryption in Massive MIMO Systems with spatial modulation

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China Communications 2018年第10期15卷 159-171页

作者： Sixin Wang Wei Li Jing Lei School of Electronic Science National University of Defense Technology

Massive multiple input and multiple output(MIMO) is a key technology of the fifth generation(5 G) wireless communication systems, which brings various advantages, such as high spectral efficiency and energy efficiency. In MIMO system, spatial modulation(SM) has recently emerged as a new transmission method. In this paper, in order to improve the security in SM-MIMO, a physical layer encryption approach named chaotic antenna-index three-dimensional modulation and constellation points rotated(CATMCPR) encryption scheme is proposed, which utilizes the chaotic theory and spatial modulation techniques. The conventional physical-layer encryption in SM-MIMO suffers from spectral efficiency(SE) performance degradation and usually needs a preshared key, prior channel state information(CSI) or excess jamming power. By contrast, we show that the CATMCPR scheme can not only achieve securely communication but also improve above drawbacks. We evaluate the performances of the proposed scheme by an analysis and computer simulations.

关键词： massive MIMO chaotic system physical layer security antenna-index spatial modulation

Performance Analysis of Uplink Massive spatial modulation MIMO Systems in Transmit-Correlated Rayleigh Channels

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China Communications 2021年第2期18卷 27-39页

作者： Qiyishu Li Xiangbin Yu Mingfeng Xie Ning Li Xiaoyu Dang College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016

In this paper,the performance of uplink multiuser massive multiple-input multipleoutput(MIMO)system with spatial modulation over transmit-correlated Rayleigh fading channel is investigated,where a large number of antennas are deployed at the base station and linear zero-forcing(ZF)receiver is employed for *** taking the transmit correlation and the randomness of shadow fading in to account,the bit error rate(BER)performance of the system is *** to the performance analysis,an approximated expression of overall average BER of the system is ***,asymptotic performance is studied and the corresponding BER expression at high signal-to-noise ratio is *** this basis,the diversity gain of the system can be obtained for performance *** results show that the derived theoretical expressions match the simulated values well,which verifies the correctness of our analysis.

关键词： bit error rate massive MIMO spatial modulation transmit correlation shadow fading ZF receiver

NOMA-Aided Generalized Pre-Coded Quadrature spatial modulation for Downlink Communication Systems

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China Communications 2020年第11期17卷 120-130页

作者： Jun Li Jia Hou Lisheng Fan Yier Yan Xue-Qin Jiang Han Hai Research Center of Intelligent Communication Engineering School of Electronics and Communication EngineeringGuangzhou UniversityGuangzhou 510006China School of Electronic and Information Engineering Soochow UniversitySuzhou 215006China School of Computer Science Guangzhou UniversityGuangzhou 510006China School of Information Science and Technology Donghua UniversityShanghai 201620China

Generalised pre-coding quadrature spatial modulation(GPQSM)is recently proposed to increase the spectral efficiency(SE)of GPSM,which extends the transmitted symbols into in-phase/quadrature *** this paper,a novel scheme named non-orthogonal multiple access(NOMA)-aided GPQSM(NOMA-GPQSM),which incorporates the GPQSM scheme into the multi-user communication networks with assist of NOMA,is proposed to further improve the SE and system *** NOMA-GPQSM,one base station(BS)is set to serve K users,where user 1 is closest to the BS,and user K is farthest from the *** addition,a low-complexity detection method is proposed to reduce the high detection complexity of the maximum-likelihood(ML)detection in successive interference cancellation(SIC)method for all users by *** theoretical analysis of the BER performance for all users is also *** results show that near users achieve relatively good performance,and far users achieve acceptable performance by adjusting power factors for all users in NOMA-GPQSM.

关键词： spatial modulation index modulation non-orthogonal multiple access bit error rate pre-coding

Hybrid prefix OFDM with spatial modulation toward terahertz broadband transmission

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Science China(Information Sciences) 2020年第8期63卷 53-55页

作者： Tiebin WANG Weipeng JING Wenlong SONG Information and Computer Engineering College Northeast Forestry University

Dear editor,In the development of 6G, terahertz communications [1] have attracted much attention owing to their potential for providing wireless broadband connections with even higher frequency resources. Furthermore, new transmission technologies have been widely considered for supporting future 6G systems [2]. Specifically, the spatial

关键词： spatial modulation ofdm cyclic prefix terahertz multiple path fading

Supervised Machine Learning Approach Based Adaptive modulation Order Selection in spatial modulation

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Supervised Machine Learning Approach Based Adaptive Modulati...

作者： TWARAYISENZE JEAN PAUL 山东大学

学位级别：硕士

In wireless communications,spatial modulation（SM）is a simple and promising multiple-input multiple-output（MIMO）technology to overcome the drawbacks existing in conventional MIMO systems for the inherent characteristics,e.g.,the activation of single transmit antenna per each symbol period to avoid inter-channel interference（ICI）and inter-antenna synchronization（IAS）.SM can also reduce the transmit power due to the activation of one transmit antenna and achieve high bit rate by additional bits conveyed by the activated antenna *** the other hand,SM is very sensitive to channel fading and *** deal with this issue,adaptive modulation order selection（MOS）is adopted in SM,where different modulation orders can be adjusted to the available channel conditions to enhance the system bit error rate（BER）***,the classical optimal adaptive MOS in SM is usually performed through conducting an exhaustive search（ES）over all the received symbols,which results in high system ***,machine learning（ML）technique has proved the efficient reduction of complexity in SM-MIMO *** this thesis,we employ supervised learning,which is a ML task of learning a function that maps an input to an output based on a labeled training ***,we utilize supervised ML technique to select the optimal modulation order in SM and provide an effective complexity-performance tradeoff under the given spectral efficiency（SE）.The main contributions of this thesis focus on the ***,two supervised machine learning classifiers（MLCs）,K-nearest neighbors（KNN）and support vector machine（SVM）are proposed to convert the classical adaptive MOS optimization problem into a multi-class classification problem and predict the modulation order candidate which provides the maximum minimum Euclidean distance（MED）by training the relevant *** a result,the system complexity is significantly reduced at the cost of marginal BER performance ***,to fu

关键词： multiple-input multiple-output spatial modulation modulation order selection K-nearest neighbors support vector machine artificial neural network

spatial Coded modulation:Coding over Antennas

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China Communications 2024年第11期21卷 104-122页

作者： Luo Junshan Wang Fanggang Wang Shilian School of Electronic Science National University of Defense TechnologyChangsha 410073China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China

In spatial modulation systems,the reliability of the active antenna detection is of vital importance since the modulated symbols tend to be correctly demodulated when the active antennas are accurately *** this paper,we propose a spatial coded modulation(SCM)scheme,which improves the accuracy of the active antenna detection by coding over the transmit ***,the antenna activation pattern in the SCM corresponds to a codeword in a properly designed codebook with a larger minimum Hamming distance than the conventional spatial *** the minimum Hamming distance increases,the reliability of the active antenna detection is directly enhanced,which yields a better system *** addition to the reliability,the proposed SCM scheme also achieves a higher capacity with the identical antenna configuration compared to the conventional *** optimal maximum likelihood detector is first ***,a low-complexity suboptimal detector is proposed to reduce the computational *** derivations of the channel capacity and the bit error rate are presented in various channel *** derivation on performance bounding is also provided to reveal the insight of the benefit of increasing the minimum Hamming *** results validate the analysis and demonstrate that the proposed SCM outperforms the conventional spatial modulation techniques in both channel capacity and system reliability.

关键词： antenna correlation channel capacity Hamming distance reliability spatial modulation

spatial-Modulated Physical-Layer Network Coding Based on Block Markov Superposition Transmission for Maritime Relay Communications

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China Communications 2020年第3期17卷 26-35页

作者： Yao Shi Liming Zheng Wenchao Lin Xiao Ma School of Data and Computer Science Sun Yat-sen UniversityGuangzhou 510006China Guangdong Key Laboratory of Information Security Technology Sun Yat-sen UniversityGuangzhou 510006China

As an alternative to satellite communications,multi-hop relay networks can be deployed for maritime long-distance *** from terrestrial environment,marine radio signals are affected by many factors,e.g.,weather conditions,evaporation ducting,and ship rocking caused by *** ensure the data transmission reliability,the block Markov superposition transmission(BMST)codes,which are easily configurable and have predictable performance,are applied in this ***,the physical-layer network coding(PNC)scheme with spatial modulation(SM)is adopted to improve the spectrum *** the BMST-SMPNC system,we propose an iterative algorithm,which utilizes the channel observations and the a priori information from BMST decoder,to compute the soft information corresponding to the XORed bits constructed by the relay *** results indicate that the proposed scheme outperforms the convolutional coded SM-PNC over fast-fading Rician ***,the performance can be easily improved in high spatial correlation maritime channel by increasing the memory m.

关键词： block Markov superposition transmission maritime relay communications physical-layer network coding Rician fading spatial modulation

Theoretical study of the trapping efficiency of an optical tweezers array system

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Chinese Physics B 2008年第2期17卷 726-735页

作者：李勤冯万力胡晓明曹群沙定国林家明 Department of Biomedical Engineering Beijing Institute of Technology Department of Opto-electronic Engineering Beijing Institute of Technology

Optical tweezers have been a valuable research tool since their invention in the 1980s. One of the most important developments in optical tweezers in recent years is the creation of two-dimensional arrays of optical traps. In this paper, a method based on interference is discussed to form gradient laser fields, which may cause the spatial modulation of particle concentration. The parameters related to the optical tweezers array are discussed in detail and simulated by the Matlab software to show the influence of important parameters on the distribution of particle concentration. The spatial redistribution of particles in a laser interference field can also be predicted according to the theoretical analysis.

关键词： optical tweezers array gradient force trapping efficiency spatial modulation

The Critical Properties of a Modulated Quantum sine—Gordon Model

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Communications in Theoretical Physics 2002年第3期37卷 353-358页

作者： WANGZhi－Guo ZHANGYu－Mei DepartmentofPhysics TongjiUniversityShanghai200092China

A new procedure of trial variational wave functional is proposed for investigating the mass renormalization and the local structure of the ground state of a one-dimensional quantum sine-Gordon model with linear spatial modulation, whose ground state differs from that without modulation. The phase diagram obtained in parameters plane shows that the vertical part of the boundary between soliton lattice phase and incommensurate (IC) phase with vanishing gap sticks at , the IC phase can only appear for and the IC phase regime is enlarged with increasing spatial modulation in the case of definite parameter . The transition is of the continuous type on the vertical part of the boundary, while it is of the first order on the boundary for .

关键词： sine-Cordon model spatial modulation soliton lattice incommensurate phase phase diagram