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A Comprehensive Survey on IRS-Assisted NOMA-Based 6G Wireless Network: Design Perspectives, Challenges and Future Directions

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IEEE TRANSACTIONS ON NETWORK AND SERVICE MANAGEMENT 2024年第2期21卷 2539-2562页

作者： Sarkar, Debbarni Yogita Yadav, Satyendra Singh Pal, Vipin Kumar, Neeraj Patra, Sarat Kumar Natl Inst Technol Meghalaya Dept ECE Shillong 793003 Meghalaya India Natl Inst Technol Kurukshetra Dept CSE Kurukshetra 136119 Haryana India Netaji Subhas Univ Technol Delhi Dept CSE New Delhi 110078 India Thapar Inst Engn & Technol Patiala 147001 Punjab India Natl Inst Technol Agartala Dept ECE Agartala 799046 India

The propagation environment was uncontrollable in first-generation to fifth-generation (5G) wireless technologies. This behavior of the wireless propagation environment is one of the prime constraints in harnessing the performance of wireless networks. This problem can be addressed in sixth-generation (6G) wireless networks by deploying intelligent reflecting surfaces (IRSs). IRS's amplitude and phase reflecting coefficient of reflecting units (RUs) can be adjusted via a programmable controller to meet the network requirements. On the other hand, in 5G and 6G wireless communication networks, non-orthogonal multiple access (NOMA) is a robust and well-admired multiple access scheme among the other multiple access counterparts in terms of spectrum efficiency and link capacity. NOMA allows many user equipment (UE) by utilizing non-orthogonal distribution of resources. Therefore, the combination of IRS and NOMA is one of the dominant technologies for 6G wireless networks. Based upon the importance of NOMA and IRS in the initial development of 6G wireless networks, this paper presents a comprehensive survey on IRS-assisted NOMA-based networks, considering their designs and challenges. In this work, the concept and structure of IRS-assisted NOMA have been explained with an in-depth analysis of the frameworks. It also includes some challenges of IRS-assisted NOMA in wireless communication networks. Further, applications and future research directions of IRS-assisted NOMA networks are discussed.

关键词： Intelligent reflecting surfaces non-orthogonal multiple access orthogonal multiple access reflecting units orthogonal frequency division multiplexing multiple input and multiple output sixth-generation

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Efficient Target Classification Based on Vehicle Volume Estimation in High-Resolution Radar Systems

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REMOTE SENSING 2024年第9期16卷 1522页

作者： Hwangbo, Sanghyeok Cho, Seonmin Kim, Junho Lee, Seongwook Korea Aerosp Univ Coll Engn Sch Elect & Informat Engn 76 Hanggongdaehak ro Goyang Si 10540 South Korea Chung Ang Univ Coll ICT Engn Sch Elect & Elect Engn 84 Heukseok ro Seoul 06974 South Korea

In this paper, we propose a method for efficient target classification based on the spatial features of the point cloud generated by using a high-resolution radar sensor. The frequency-modulated continuous wave radar sensor can estimate the distance and velocity of a target. In addition, the azimuth and elevation angle of the target can be estimated by using a multiple-input and multiple-output antenna system. Using the estimated distance, velocity, and angle, the 3D point cloud of target can be generated. From the generated point cloud, we extract the point cloud for each individual target using the density-based spatial clustering of application with noise method and a camera mounted on the radar sensor. Then, we define the convex hull boundaries that enclose these point clouds in both 3D and 2D spaces obtained by orthogonally projecting onto the xy, yz, and zx planes. Using the vertices of convex hull, we calculate the volume of the targets and the areas in 2D spaces. Several feature points, including the calculated spatial information, are numerized and configured into feature vectors. We design an uncomplicated deep neural network classifier based on minimal input information to achieve fast and efficient classification performance. As a result, the proposed method achieved an average accuracy of 97.1%, and the time required for training was reduced compared to the method using only point cloud data and the convolutional neural network-based method.

关键词： deep neural network frequency-modulated continuous wave multiple input and multiple output quickhull algorithm target classification

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An Integrated DRA-Based Large Frequency Ratio Antenna System Consisting of a MM-Wave Array and a MIMO Antenna for 5G Applications

IEEE OPEN JOURNAL OF ANTENNAS AND PROPAGATION

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IEEE OPEN JOURNAL OF ANTENNAS AND PROPAGATION 2024年第2期5卷 368-378页

作者： Muhammad, Awab Khan, Muhammad U. Malfajani, Reza Shamsaee Sharawi, Mohammad S. Alathbah, Moath Natl Univ Sci & Technol SEECS Islamabad 44000 Pakistan Polytech Montreal Dept Elect Engn Montreal PQ H3T 1J4 Canada Blue Origin LLC Kent WA 98032 USA King Saud Univ Coll Engn Dept Elect Engn Riyadh 11421 Saudi Arabia

This paper presents a large frequency ratio antenna that covers the widely separated 5G bands. The proposed antenna consists of a 2-element rectangular DRA (rDRA)-based MIMO antenna for the sub-6 GHz band, with an embedded $1\times 4$ cylindrical DRA (cDRA) array covering the mmW band. The rDRAs are fabricated through a cost and time-efficient 3D printing process, whereas small dimensions of cDRAs are precisely machined through a CNC. The proposed antenna has a measured impedance bandwidth of 31.63% at 4.9 GHz and 21.5% at 28 GHz. The antenna has a peak gain of 6.6 dBi at the sub-6 GHz and 12 dBi at the mmW bands. Moreover, the proposed antenna has an Envelope Correlation Coefficient (ECC) of less than 0.01, whereas the simulated beam steering performance of the antenna exhibits good performance for the sector of +/- 50(degrees).

关键词： Large frequency ratio antenna dielectric resonator antenna multiple input and multiple output beamforming array antenna 5G

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Lightweight micro-motion gesture recognition based on MIMO millimeter wave radar using Bidirectional-GRU network

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NEURAL COMPUTING & APPLICATIONS 2023年第32期35卷 23537-23550页

作者： Zhao, Yaqin Song, Yuqing Wu, Longwen Liu, Puqiu Lv, Ruchen Ullah, Hikmat Harbin Inst Technol Sch Elect & Informat Engn Harbin 150001 Peoples R China China Aerosp Sci & Ind Corp Res Inst 8511 Nanjing 211100 Peoples R China

Non-contact gesture recognition is a novel form of human-computer interaction. It has broad prospects in many applications, such as Augmented Reality/Virtual Reality, smart homes and intelligent medical systems. Therefore, it has become a research hotspot in recent years. This paper investigates a lightweight micro-motion gesture recognition method based on multiple input and multiple output millimeter wave radar. We employ TI's MMWCAS radar, comprising four cascaded AWR1243 radar boards, to collect gesture data. During the data pre-processing stage, we extract the Range-time Map, Doppler-time Map, Azimuth-time Map and Elevation-time Map of the dynamic gestures to characterize the dynamic motion features. These maps are then simplified into a one-dimensional vector to reduce data volume. We propose an 8HBi-GRU model, which combines the Bidirectional Gate Recurrent Unit (Bi-GRU) with a multi-head self-attention mechanism, to identify twelve types of micro-motion gestures using feature vectors. The model achieves an accuracy of 98.24%, with precision and recall rates exceeding 0.97 and 0.98, respectively, for ten of the gesture types. Experimental results demonstrate that the proposed 8HBi-GRU model achieves lightweight gesture recognition rapidly and requires minimal storage space compared to image-based deep learning methods.

关键词： Hand gesture recognition Millimeter wave radar multiple input and multiple output Multi-head self-attention

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Adaptive Threshold of Compressed Sensing for AUD 8

Adaptive Threshold of Compressed Sensing for AUD

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8th International Conference on Communication and Information Systems, ICCIS 2024

作者： Luo, Yuan Sun, Haoyue Dang, Jiaojiao Wei, Guangfen Shandong Technology and Business University College of Electronics and Information Engineering Yantai China

ISBN: (纸本)9798331531171

With the rapid development of wireless communication technology, the number of smart terminals in the network has been steadily increasing. However, the interference and complex environments resulting from multi-user access present significant challenges for user detection and channel estimation. To address these limitations, we propose an adaptive active user detection method based on compressed sensing techniques. This approach utilizes the orthogonal matching pursuit algorithm to adaptively adjust detection thresholds in response to varying noise conditions, thereby optimizing the accuracy of signal reconstruction while maintaining low computational complexity. Simulation results indicate that this method effectively enhances the accuracy of signal reconstruction across different noise environments, significantly improving the environmental adaptability of the compressed sensing algorithm. © 2024 IEEE.

关键词： active user detection compressed sensing multiple input and multiple output orthogonal matching pursuit

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Multiplicative Basis Function Based Adaptive DOA Estimation in Optimal MIMO Sparse Antenna Reconfiguration Model

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IETE JOURNAL OF RESEARCH 2024年第9期70卷 7219-7230页

作者： Anughna, Narayanaswamy Ramesha, Muniyappa GITAM GITAM Sch Technol Dept Elect Elect & Commun Engn Bengaluru India

Direction of arrival (DOA) estimation using sparse signal representation has gained significant attention in recent decades. The spatial signals utilized for DOA estimation are reconstructed through a novel compressive sensing (CS) approach. In this study, we used a CS approach to ascertain the adaptive underdetermined DOA for multiple inputs and multiple output (MIMO) sparse media. Accurate DOA estimation through the CS approach contributes to enhanced signal investigation and the suppression of undesired noise in a sparse channel. The method proposed herein encompasses the development and execution of a novel multiplicative basis function known as the multi-kernel supported non-negative sparse Bayesian learning (NNSBL) algorithm, which is implemented on predefined grid values. Concurrently, stochastic grey wolf optimization (GWO) is virtually applied to increase the degrees of freedom (DOF) on a minimum redundancy array (MRA) while considering an optimal antenna reconfiguration model. The advantages of this proposed approach include the generation of a distinct manifold matrix for precise beam steering, resulting in improved DOA estimation accuracy. Additionally, an augmentation of DOF using GWO was observed, with low computational complexity. The simulated result of proposed algorithm leads to the attainment of optimal minimum root mean square error (RMSE) across various optimal wavelengths of the stochastic sources. Finally, a comparative analysis of RMSE and convergence plots confirms the superior performance and high potentiality of the proposed method in comparison to existing techniques across different SNR values. Notably, there is significant reduction in RMSE which is suitable for precise DOA estimation in signal processing applications.

关键词： Compressive sensing DOA Grey wolf optimization Minimum redundancy array multiple input and multiple output Non-negative sparse Bayesian learning

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A new method for optimizing the topology of hinge-free and fully decoupled compliant mechanisms with multiple inputs and multiple outputs

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INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING 2021年第12期122卷 2863-2890页

作者： Rong, Jianhua Rong, Xuanpei Peng, Luo Yi, Jijun Zhou, Quan Changsha Univ Sci & Technol Sch Vehicle & Mech Engn Changsha 410076 Hunan Peoples R China Hunan Univ State Key Lab Adv Design & Mfg Vehicle Body Changsha Peoples R China China Construct Fifth Engn Bur Ltd Changsha Peoples R China

Compliant mechanisms with multiple inputs and multiple outputs have a wide range of applications in precision mechanics, for example, cell manipulations, electronic microscopes, and so on. The movement uncoupling and maximum desired output displacements among these devices all become critical because many inputs and outputs are involved. The topology optimization design of compliant mechanisms, which can solve output coupling and input coupling problems, hinge and gray region problems, and the multiple-objective optimal problem, is an important topic of researches for achieving fully decoupled motion. It is also a challenge area of research due to serious conflicts of between the four of output and input uncoupling constraints, volume constraint, the hinge-free requirement, and the good black/white solution requirement. In order to comprehensively solve these problems, a simple optimization model overcoming these serious conflicts is posed, which includes small change rate constraints of structural compliances corresponding to the driving input loads and output point virtual loads. Then, the multiple output displacement functions of the model are equivalently converted into non-negative functions. The multiple-objective model is converted into a single-objective optimization model by using a bound variable. The method of moving asymptotes (MMA) algorithm is adopted to solve it. Several examples are presented to demonstrate the validity of the proposed method.

关键词： bound formulation method compliant mechanism hinge‐ free movement uncoupling multiple input and multiple output multiple‐ objective optimization topology optimization

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A Survey on 5G Coverage Improvement Techniques: Issues and Future Challenges

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SENSORS 2023年第4期23卷 2356页

作者： Sudhamani, Chilakala Roslee, Mardeni Tiang, Jun Jiat Rehman, Aziz Ur Multimedia Univ Fac Engn Ctr Wireless Technol Cyberjaya 63100 Selangor Malaysia

Fifth generation (5G) is a recent wireless communication technology in mobile networks. The key parameters of 5G are enhanced coverage, ultra reliable low latency, high data rates, massive connectivity and better support to mobility. Enhanced coverage is one of the major issues in the 5G and beyond 5G networks, which will be affecting the overall system performance and end user experience. The increasing number of base stations may increase the coverage but it leads to interference between the cell edge users, which in turn impacts the coverage. Therefore, enhanced coverage is one of the future challenging issues in cellular networks. In this survey, coverage enhancement techniques are explored to improve the overall system performance, throughput, coverage capacity, spectral efficiency, outage probability, data rates, and latency. The main aim of this article is to highlight the recent developments and deployments made towards the enhanced network coverage and to discuss its future research challenges.

关键词： cellular network network coverage small cells device to device communication non-orthogonal multiple access optimization multiple input and multiple output

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Novel 3-D Irregular-Shaped Geometry-Based Channel Modeling for Semi-Ellipsoid Vehicle-to-Vehicle Scattering Environments

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IEEE WIRELESS COMMUNICATIONS LETTERS 2018年第5期7卷 836-839页

作者： Jiang, Hao Zhang, Zaichen Wu, Liang Dang, Jian Southeast Univ Natl Mobile Commun Res Lab Nanjing 210096 Jiangsu Peoples R China

This letter presents a 3-D irregular-shaped geometry-based stochastic model for vehicle-to-vehicle (V2V) radio propagation environments, in which an asymmetric directional multiple input and multiple output technique is employed at the mobile transmitter (MT). The time-varying geometric path lengths are introduced in the proposed channel model to capture the non-stationarity, which is caused by the motion of the MT and mobile receiver. More importantly, the impacts of the model parameters and non-stationarity, i.e., relative moving directions and relative moving time, on the channel statistical properties are investigated. The results show that the proposed 3-D model fits the prior results very well, which demonstrate that the model is practical to provide guidelines for the system design and performance analysis of V2V communication systems.

关键词： 3D IS-GBSM vehicle-to-vehicle multiple input and multiple output non-stationarity

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Circular Slotted Ring Shaped Mimo Antenna For Ultra Wideband Applications 9

Circular Slotted Ring Shaped Mimo Antenna For Ultra Wideband...

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9th IEEE International Conference on Computational Intelligence and Computing Research (ICCIC)

作者： Kumar, J. Prasanth Karunakar, G. GITAM Univ ECE Visakhapatnam Andhra Pradesh India RCE ECE Eluru India GITAM Univ Gitam Inst Technol ECE Dept Vishakapatnam India

ISBN: (纸本)9781538615072

A MIMO Orthogonally arranged two-element antenna consists defected ground structure is designed and analyzed in this article. The proposed antenna which is orthogonally placed with low isolation is designed to operate in frequency range from 3.6-11.0GHz which also covers UWB frequency range nearly. The Designed antenna is used to cover the many applications like WiMAX, WLAN, under ultra wideband range. The designed antenna consists a partial ground with two circular rings which is excited by using micro strip line feeding. The proposed MIMO antenna works in all c band and x band applications which are very useful for mobile and satellite *** obtained result show that antenna's impedance bandwidth 102% from3.6-11GHz i.e., at ultra wide band. The antenna gives maximum gain of 5.4dBi at 8. 2GHz. ANSYS HFSS software is used for design of it and the results are analyzed. Parameters like reflection coefficient, e-field radiation patterns and current distributions are discussed. From the results it is observed that this antenna application is suited for hand-held and portable mobile applications in day to day life at ultra-wideband technology.

关键词： ultra wideband range notch band defected ground structure multiple input and multiple output mutual copling

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