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13th International Conference on Advanced Technologies for Communications (ATC)

作者： Chu Tien Dung Le Xuan Hung Tran Manh Hoang Hoang Van Toan Le The Dung Telecommun Univ Nha Trang Vietnam Chungbuk Natl Univ Dept Radio & Commun Engn Cheongju South Korea

ISBN: (数字)9781728180656

ISBN: (纸本)9781728180656

In this paper, we investigate the physical layer security of a multiple-input and multiple-output (MIMO) relay system under imperfect channel state information (CSI). We propose using multiple antennas at the source and destination to increase the signal-to-noise (SNR) gain of the primary channel, thus improving the system's security performance. Exact closedform expression of the secure outage probability (SOP) and secrecy capacity (SC) are derived and verified by Monte-Carlo simulations. A close match between the theoretical and simulation results confirms the accurateness of our mathematical analysis. We show that the SOP decreases while the SC increases as the average SNR is higher. Furthermore, the saturated minimum and maximum values highly depend on the number of antennas at source and destination, the degree of imperfect CSI, and the location of eavesdropper.

关键词： multiple-input and multiple-output imperfect channel state information transmit/receive antenna selection secrecy outage probability secrecy capacity

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Design an Efficient Meta-Heuristic Chameleon Swarm Optimization Algorithm for Mutual Coupling Reduction in Slotted Fractal MIMO Antenna

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Microwave and Optical Technology Letters 2025年第6期67卷

作者： Palniladevi Paulpandian Sabapathi Thangavinayagam Department of Electronics and Communication Engineering Mepco Schlenk Engineering College Sivakasi Tamil Nadu India

multiple-input and multiple-output have become fundamental components of wireless communication systems owing to their powerful beamforming capabilities and fast data rates. However, the compact design required for wireless systems leads to closely spaced antenna elements in multiple-input and multiple-output systems, resulting in mutual coupling that degrades total system performance. This study presents a decoupling method based on the Chameleon Swarm Optimization Algorithm to reduce mutual coupling between two densely packed Slotted Fractal multiple-input and multiple-output antenna, while maintaining low correlation between elements. Each element in the proposed antennas has a size of 26 × 35.5 × 3.2 mm 3 and is made of FR4 substrate material with a center frequency of 4.55 GHz. The Envelope Correlation Coefficient is reduced to 0.03 by lowering the mutual coupling denoted by S 12 to less than −44 dB with the support of the Chameleon Swarm Optimization Algorithm and improved gain of 8.17 dBi. The developed MIMO antenna is optimized for sub-6 GHz 5 G applications, specifically covering bands n77, n78, and n79. The design is evaluated using MATLAB Software for antenna design and optimization process.

关键词： Chameleon Swarm Optimization Algorithm Diversity Gain and Radiation Pattern Envelope Correlation Coefficient fractal antenna multiple-input and multiple-output mutual coupling

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ARM: Adaptive Random-Selected Multi-Beamforming Estimation Scheme for Satellite-Based Internet of Things

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IEEE ACCESS 2019年 7卷 63264-63276页

作者： Wang, Ye Li, Qiwen Jiao, Jian Wu, Shaohua Zhang, Qinyu Harbin Inst Technol Shenzhen Commun Engn Res Ctr Shenzhen 518055 Peoples R China Peng Cheng Lab Shenzhen 518055 Peoples R China

In this paper, we focus on the millimeter-wave (mmWave) band multiple-input and multiple-output (MIMO) channel estimation in the satellite-based Internet of Things (S-IoT). At first, we establish a sparse geometric-based mmWave MIMO channel model between a high throughput satellite (HTS) and multiple terrestrial user equipments (UEs) for the S-IoT downlink system. By exploiting the sparsity inherent to themmWave band channel, we propose an efficient adaptive random-selected multi-beamforming (ARM) estimation scheme, which can simultaneously estimate themmWave MIMO channel state information (CSI) for multiple UEs in angle domain. The ARM estimation scheme measures of the CSI between the HTS and multiple UEs by utilizing a series of random combinations of transmitting beamforming vectors and receiving UEs' antennas and the required number of measurements can adaptively reduce as well as the signal-to-noise ratios (SNR) increases. To further improve the performance of ARM estimation scheme, the number of each beamforming been selected for the channel measurement is buffered, and modify the probability of the random selection of beams and UEs. Two improved ARM estimation schemes are proposed, one is ARM forcing adaptation beam selection (ARM-FABS) scheme, and the other is ARM partially estimated beam selection (ARM-PEBS) scheme. The simulation results show that the proposed ARM estimation schemes can reduce the required number of measurements and achieve a better tracking performance over a wide range of SNRs.

关键词： Satellite-based Internet of Things millimeter-wave band multiple-input and multiple-output channel estimation

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Enhanced redesigned spatial modulation: Design and performance evaluation under correlated fading channels

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INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS 2020年第6期33卷 e4294-e4294页

作者： Gudla, Vishnu Vardhan Kumaravelu, Vinoth Babu Vellore Inst Technol Sch Elect Engn Dept Commun Engn Vellore 632014 Tamil Nadu India

Spatial modulation techniques (SMTs) have emerged as promising multiple-input and multiple-output (MIMO) technology for fifth generation (5G) networks, which can achieve an appealing trade-off between conflicting design objectives such as reliability, hardware cost, complexity, spectral efficiency, and energy efficiency. Most of the SMTs suffer from significant performance deterioration under correlated fading channels. In this paper, a novel spectral efficient SMT referred as enhanced redesigned spatial modulation (EReSM) is proposed, which is robust against adverse channel correlation effects. At any time instant, EReSM activates either one or two transmit antennas and employs a robust bits to antenna index mapping that ensures the selection of antenna subsets with maximum spatial separation to mitigate the effect of spatial correlation. EReSM also exploits phase rotation of transmitted symbols as an additional dimension to convey an extra information bit. The rotation angles used for bit mapping are optimized for various modulation schemes to maximize the minimum euclidean distance between the symbols. To analyze the performance, analytical upper bound expression for average bit error probability (ABEP) is derived for both uncorrelated and spatially correlated channel conditions. Monte Carlo simulation results substantiate the accuracy of the analytical results and also demonstrate that the proposed EReSM outperform conventional redesigned spatial modulation (ReSM) by at least 4 dB.

关键词： enhanced redesigned spatial modulation fifth generation networks multiple-input and multiple-output phase rotation redesigned spatial modulation spatial modulation techniques

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Precoder design in downlink Co MP-JT MIMO network via WMMSE and asynchronous ADMM

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Science China(Information Sciences) 2018年第8期61卷 209-221页

作者： Zhikun WU Zesong FEI School of Information Science and Engineering Beijing Institute of Technology

Precoder design of coordinated multi-point joint transmission(Co MP-JT) multiple-input and multiple-output(MIMO) network aimied at throughput maximization is a challenging problem. In this paper, we propose an asynchronous distributed iterative method to solve this problem. We transform the original throughput maximizing problem to the weighted minimum mean square error(WMMSE) problem,then decompose the problem into a series of subproblems. Based on alternation direction method of multipliers(ADMM), the proposed algorithm can solve the optimal precoder in a distributed manner. With asynchronous information exchange mechanism considered, the convergence rate of our algorithm can be accelerated further. Numerical results demonstrate the increase of throughput and the optimality of the precoding scheme provided by our algorithm.

关键词： multiple-input and multiple-output coordinated multi-point joint transmission weighted minimum mean square error block coordinate descent alternation direction method of multipliers asynchronous method

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Decoupling between ground radiation antennas with ground-coupled loop-type isolator for WLAN applications

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IET MICROWAVES ANTENNAS & PROPAGATION 2016年第5期10卷 546-552页

作者： Qu, Longyue Zhang, Rui Kim, Hyeongdong Hanyang Univ Dept Elect Engn 222 Wangsimni Ro Seoul 133791 South Korea

A compact and easy to fabricate decoupling method is proposed to yield high isolation for the multiple-input and multiple-output (MIMO) ground radiation antenna (GradiAnt) system. The proposed MIMO antenna system is comprised of two symmetrical, closely spaced, loop-type (GradiAnts) with a ground-coupled loop-type isolator inserted between them. The isolator can be seen as a series resonant circuit which is connected with lumped components to control decoupling. In the proposed MIMO GradiAnt system, a coupling null is induced due to the ground-coupled isolator, which effectively can be used for isolation enhancement between two GradiAnts. Within WLAN band, a minimum 14 dB isolation with a peak value of 42 dB at 2.42 GHz is achieved. In this manuscript, the decoupling principle and controlling mechanisms are first explained, then the antenna performances and tuning mechanisms are discussed in detail. The simulation and the measurement of the MIMO antenna, including the scattering parameters, efficiency, radiation patterns, peak gains and envelope correlation coefficients are conducted to verify the performance of the proposed MIMO system.

关键词： wireless LAN MIMO communication antenna radiation patterns ground coupled loop type isolator WLAN applications fabricate decoupling method multiple-input and multiple-output MIMO ground radiation antenna GradiAnt system series resonant circuit lumped components MIMO GradiAnt system tuning mechanisms envelope correlation coefficients

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A Multivariate EWMA Controller for Linear Dynamic Processes

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TECHNOMETRICS 2016年第1期58卷 104-115页

作者： Tseng, Sheng-Tsaing Mi, Hsin-Chao Lee, I. - Chen Natl Tsing Hua Univ Inst Stat Hsinchu 30013 Taiwan

Most research of run-to-run process control has been based on single-input and single-output processes with static input-output relationships. In practice, many complicated semiconductor manufacturing processes have multiple-input and multiple-output (MIMO) variables. In addition, the effects of previous process input recipes and output responses on the current outputs might be carried over for several process periods. Under these circumstances, using conventional controllers usually results in unsatisfactory performance. To overcome this, a complicated process could be viewed as dynamic MIMO systems with added general process disturbance and this article proposes a dynamic-process multivariate exponentially weighted moving average (MEWMA) controller to adjust those processes. The long-term stability conditions of the proposed controller are derived analytically. Furthermore, by minimizing the total mean square error (TMSE) of the process outputs, the optimal discount matrix of the proposed controller under vector IMA(1, 1) disturbance is derived. Finally, to highlight the contribution of the proposed controller, we also conduct a comprehensive simulation study to compare the control performance of the proposed controller with that of the single MEWMA and self-tuning controllers. On average, the results demonstrate that the proposed controller outperforms the other two controllers with a TMSE reduction about 32% and 43%, respectively.

关键词： multiple-input and multiple-output Multivariate exponentially weighted moving average controller Run-to-run process control

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A HIGH ISOLATION DUAL-BAND MIMO ANTENNA ARRAY FOR MULTIACCESS MOBILE TERMINALS

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2015年第3期57卷 672-677页

作者： Zhai, Huiqing Zhang, Jian Li, Tong Liang, Changhong Xidian Univ Natl Key Lab Antennas & Microwave Technol Sch Elect Engn Xian 710071 Shaanxi Peoples R China

To satisfy more requirements in wireless communication, a compact dual-band multiple-input and multiple-output (MIMO) antenna array is designed for the multiaccess mobile terminals. The proposed MIMO system consists of six elements of two types of planar inverse-F antennas (PIFAs), including four U-slit etched PIFAs and two sawtooth U-slit etched PIFAs. For increasing the isolation between different elements, we mainly adopt three methods in the design, including the disconnected ground plane, the isolation strips, including T-strips and inverse p-strips, and also the modified PIFAs. It can be found that all of the elements could operate at 2.55-2.60 GHz around band LTE and 3.51-3.65 GHz for band WiMAX normally while the return loss and isolation are lower than -10 dB and -20 dB, respectively. Besides, the overall dimension of the multiaccess system is 120 x 70 x 10.4 mm(3), in which the radiation patterns of the antenna is quasi-omnidirectional and the envelop correlation coefficient between ports is below 0.5. (C) 2015 Wiley Periodicals, Inc.

关键词： dual band multiple-input and multiple-output LTE/WiMAX mobile applications planar inverted-F antenna excellent isolation

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Performance Analysis of Layer Pruning on Sphere Decoding in MIMO Systems

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ETRI JOURNAL 2014年第4期36卷 563-570页

作者： Karthikeyan, Madurakavi Saraswady, D. Pondicherry Engn Coll Dept Elect & Commun Engn Pondicherry India

Sphere decoding (SD) for multiple-input and multipleoutput systems is a well-recognized approach for achieving near-maximum likelihood performance with reduced complexity. SD is a tree search process, whereby a large number of nodes can be searched in an effort to find an estimation of a transmitted symbol vector. In this paper, a simple and generalized approach called layer pruning is proposed to achieve complexity reduction in SD. Pruning a layer from a search process reduces the total number of nodes in a sphere search. The symbols corresponding to the pruned layer are obtained by adopting a QRM-MLD receiver. Simulation results show that the proposed method reduces the number of nodes to be searched for decoding the transmitted symbols by maintaining negligible performance loss. The proposed technique reduces the complexity by 35% to 42% in the low and medium signal-to-noise ratio regime. To demonstrate the potential of our method, we compare the results with another well-known method - namely, probabilistic tree pruning SD.

关键词： Sphere decoding multiple-input and multiple-output MIMO tree pruning layer pruning QRM-MLD

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Energy-efficient uplink power control for multiuser SIMO systems with imperfect channel state information

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EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING 2014年第1期2014卷 1页

作者： Jang, Moonheok Kwon, Younggap Park, Hyunsung Hwang, Taewon Yonsei Univ Sch Elect & Elect Engn Seoul 120749 South Korea

This paper addresses energy-efficient design for uplink multiuser SIMO systems with imperfect channel state information (CSI) at the base station (BS). Since the CSI at the BS is always imperfect due to the channel estimation error and delay, the imperfectness of the CSI needs to be considered in practical system design. It causes interuser interference at the zero-forcing (ZF) receiver and makes it difficult to obtain the globally optimal power allocation that maximizes the energy efficiency (EE). Hence, we propose a non-cooperative energy-efficient uplink power control game, where each user selfishly updates its own uplink power. The proposed uplink power control game is shown to admit a unique Nash equilibrium. Furthermore, to improve the efficiency of the Nash equilibrium, we study a new game that utilizes a pricing mechanism. For the new game, the existence of a Nash equilibrium and the convergence of the best response dynamics are studied based on super-modularity theory. Simulation results show that the proposed schemes can significantly improve the EEs of the mobile users in uplink multiuser SIMO systems.

关键词： Energy efficiency Multiuser multiple-input and multiple-output Uplink Channel state information Game theory Nash equilibrium

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