A Survey of mmWave-Based Human Sensing: Technology, Platforms and Applications

IEEE Communications Surveys & Tutorials, Год журнала: 2023, Номер 25(4), С. 2052 - 2087

Опубликована: Янв. 1, 2023

With the rapid development of Internet Things (IoT) and rise 5G communication networks automatic driving, millimeter wave (mmWave) sensing is emerging starts impacting our life workspace. mmWave can sense humans objects in a contactless way, providing fine-grained ability. In past few years, many techniques have been proposed applied various human applications (e.g., localization, gesture recognition, vital monitoring). We discover need comprehensive survey to summarize technology, platforms mmWave-based sensing. this survey, we first present hardware some key then provide review existing works. Specifically, divide works into four categories according granularity: tracking motion biometric measurement imaging. Finally, discuss potential research challenges future directions area.

Язык: Английский

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Integrated Sensing and Communications With Reconfigurable Intelligent Surfaces: From signal modeling to processing

IEEE Signal Processing Magazine, Год журнала: 2023, Номер 40(6), С. 41 - 62

Опубликована: Сен. 1, 2023

Integrated sensing and communications (ISAC) are envisioned to be an integral part of future wireless networks, especially when operating at the millimeter-wave (mm-wave) terahertz (THz) frequency bands. However, establishing connections these high frequencies is quite challenging, mainly due penetrating path loss that prevents reliable communication sensing. Another emerging technology for next-generation systems reconfigurable intelligent surface (RIS), which refers hardware-efficient planar structures capable modifying harsh propagation environments. In this article, we provide a tutorial-style overview applications benefits RISs functionalities in general, ISAC particular. We highlight potential advantages fusing two technologies, identify first time 1) joint (S&C) designs most beneficial channels referring operations coupled, 2) offer means controlling coupling. The usefulness RIS-aided goes beyond obvious individual gains each technologies both performance power efficiency. also discuss main signal processing challenges research directions arise from fusion technologies.

Язык: Английский

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Joint Active and Passive Beamforming Design for Reconfigurable Intelligent Surface Enabled Integrated Sensing and Communication

IEEE Transactions on Communications, Год журнала: 2023, Номер 71(4), С. 2457 - 2474

Опубликована: Фев. 16, 2023

To exploit the potential of reconfigurable intelligent surface (RIS) in supporting integrated sensing and communication (ISAC), this paper proposes a novel joint active passive beamforming design for RIS-enabled ISAC system consideration target size. First, detection probability is derived closed-form based on illumination power an approximated scattering area target, new concept ultimate resolution (UDR) defined first time to measure capability. Then, optimization problem formulated maximize signal-to-noise ratio (SNR) at user-equipment (UE) under minimum constraint. solve non-convex problem, alternative approach developed. In approach, solutions beamformers are obtained by our proposed bisection-search method. The optimal receive combining vector from equivalent Rayleigh-quotient problem. optimize RIS phase shifts, Charnes-Cooper transformation conducted cope with fractional objective, convexification process convexify constraint matrix operations real-valued first-order Taylor expansion. After convexification, successive convex approximation (SCA) algorithm designed yield suboptimal phase-shift solution. Finally, overall built, followed detailed analyses its computational complexity, convergence behavior feasibility condition. Extensive simulations carried out testify analytical properties design, reveal two important trade-offs, namely, vs. trade-off UDR sensing-duration trade-off. comparison several existing benchmarks, validated be superior when detecting targets practical sizes.

Язык: Английский

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A Survey on Reconfigurable Intelligent Surface for Physical Layer Security of Next-Generation Wireless Communications

IEEE Open Journal of Vehicular Technology, Год журнала: 2024, Номер 5, С. 172 - 199

Опубликована: Янв. 1, 2024

Unprecedented growth in wireless data traffic, and ever-increasing demand for highly secured, low-latency communication has motivated the research community to move towards sixth-generation (6 G) technology, where networks can cater rising need ubiquitous secure connectivity. One of promising technologies 6 G is reconfigurable intelligent surface (RIS) concept that proposed successfully deal with increasing security threats by smartly controlling channel conditions. This survey paper presents a detailed literature review on RIS-assisted physical layer (PLS) next-generation communications. Firstly, we briefly discuss PLS concept, its importance, performance metrics, applicability different networks. Next, applications RIS scenario. Then, systematic classification various system topologies exhibiting multiple scenarios, models, fading metrics objectives done. The existing state-of-art approaches such as secret key generation (SKG), optimization algorithms, namely semidefinite relaxation-successive convex approximation (SDR-SCA) optimize coefficients, optimal placement units are discussed single-input single-output (SISO) case. For multiple-input (MISO) case, strategies inducing artificial noise (AN), alternating (AO), machine learning (ML) deep (DL), reflect matrices discussed. Similarly, multiple-output (MIMO) setup, block coordinate descent (BCD) AN induction some methods used analyze secrecy. Lastly, present technical challenges future directions based survey.

Язык: Английский

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Active Reconfigurable Intelligent Surface-Assisted MISO Integrated Sensing and Communication Systems for Secure Operation

IEEE Transactions on Vehicular Technology, Год журнала: 2022, Номер 72(4), С. 4919 - 4931

Опубликована: Дек. 7, 2022

Spectrum congestion has motivated the recent introduction of integrated sensing and communication (ISAC) systems where radar communications functionalities co-exist share same spectrum. This is accompanied by extensive research in area reconfigurable intelligent surfaces (RIS), thanks to their ability improve ISAC systems. In this paper, physical layer security a multiuser multiple-input single-output (MU-MISO) system investigated when subject eavesdropping malicious unmanned aerial vehicle (UAV). particular, we propose using an active RIS maximize achievable secrecy rate through jointly designing receive beamformers, reflection coefficients matrix transmit beamformers at dual-function base station system. done while taking into account minimum detection signal-to-noise ratio (SNR) total power budget constraints. The resulting non-convex optimization problem tackled exploiting fractional programming (FP) majorization-minimization (MM) techniques achieve solution. Our numerical results show superiority goal compared with passive or without RIS. Results also that could still be viable solution but expense much larger needed size especially lower budgets are available.

Язык: Английский

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Joint Location and Beamforming Design for STAR-RIS Assisted NOMA Systems

IEEE Transactions on Communications, Год журнала: 2023, Номер 71(4), С. 2532 - 2546

Опубликована: Фев. 22, 2023

Simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) assisted non-orthogonal multiple access (NOMA) communication systems are investigated in its vicinity, where a STAR-RIS is deployed within predefined region for establishing links users. Both beamformer-based NOMA cluster-based schemes employed at the multi-antenna base station (BS). For each scheme, deployment location, passive beamforming (BF) of STAR-RIS, active BF BS jointly optimized maximizing weighted sum-rate (WSR) To solve resultant non-convex problems, an alternating optimization (AO) algorithm proposed, successive convex approximation (SCA) semi-definite programming (SDP) methods invoked iteratively addressing non-convexity sub-problem. Numerical results reveal that 1) WSR performance can be significantly enhanced by optimizing specific location STAR-RIS; 2) both prefer asymmetric deployment.

Язык: Английский

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RIS-Aided Cell-Free Massive MIMO Systems for 6G: Fundamentals, System Design, and Applications

Proceedings of the IEEE, Год журнала: 2024, Номер 112(4), С. 331 - 364

Опубликована: Апрель 1, 2024

An introduction of intelligent interconnectivity for people and things has posed higher demands more challenges sixth-generation (6G) networks, such as high spectral efficiency energy (EE), ultralow latency, ultrahigh reliability. Cell-free (CF) massive multiple-input-multiple-output (mMIMO) reconfigurable surface (RIS), also called reflecting (IRS), are two promising technologies coping with these unprecedented demands. Given their distinct capabilities, integrating the to further enhance wireless network performances received great research development attention. In this article, we provide a comprehensive survey on RIS-aided CF mMIMO communication systems. We first introduce system models focusing architecture application scenarios, channel models, protocols. Subsequently, summarize relevant studies operation resource allocation, providing in-depth analyses discussions. Following this, present practical faced by systems, particularly those introduced RIS, hardware impairments (HIs) electromagnetic interference (EMI). corresponding solutions facilitate implementation Furthermore, explore an interplay between other emerging 6G technologies, millimeter wave (mmWave) terahertz (THz), simultaneous information power transfer (SWIPT), next-generation multiple access (NGMA), unmanned aerial vehicle (UAV). Finally, outline several directions future

Язык: Английский

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Adaptive 5G-and-beyond network-enabled interpretable federated learning enhanced by neuroevolution

Science China Information Sciences, Год журнала: 2024, Номер 67(7)

Опубликована: Июнь 27, 2024

Язык: Английский

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On Secrecy Performance of RIS-Assisted MISO Systems Over Rician Channels With Spatially Random Eavesdroppers

IEEE Transactions on Wireless Communications, Год журнала: 2024, Номер 23(8), С. 8357 - 8371

Опубликована: Янв. 9, 2024

Reconfigurable intelligent surface (RIS) technology is emerging as a promising technique for performance enhancement next-generation wireless networks. This paper investigates the physical layer security of an RIS-assisted multiple-antenna communication system in presence random spatially distributed eavesdroppers. The RIS-to-ground channels are assumed to experience Rician fading. Using stochastic geometry, exact distributions received signal-to-noise-ratios (SNRs) at legitimate user and eavesdroppers located according Poisson point process (PPP) derived, closed-form expressions secrecy outage probability (SOP) ergodic capacity (ESC) obtained provide insightful guidelines design. First, diversity order 2/α ₂ , where α denotes path loss exponent links. Then, it revealed that mainly affected by number RIS reflecting elements, N impact transmit antennas power base station marginal. In addition, when locations randomly unknown, deploying closer rather than shown be more efficient. Moreover, also found density eavesdroppers, λ xmlns:xlink="http://www.w3.org/1999/xlink">e has additive effect on asymptotic ESC given log (1/λ ). Finally, numerical simulations conducted verify accuracy these theoretical observations.

Язык: Английский

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Robust Beamforming Design for RIS-Aided Cell-Free Systems With CSI Uncertainties and Capacity-Limited Backhaul

IEEE Transactions on Communications, Год журнала: 2023, Номер 71(8), С. 4636 - 4649

Опубликована: Май 18, 2023

In this paper, we consider the robust beamforming design in a reconfigurable intelligent surface (RIS)-aided cell-free (CF) system considering channel state information (CSI) uncertainties of both direct channels and cascaded at transmitter with capacity-limited backhaul. We jointly optimize precoding access points (APs) phase shifts multiple RISs to maximize worst-case sum rate CF subject constraints maximum transmit power APs, unit-modulus shifts, limited backhaul capacity, bounded CSI errors. By applying series transformations, non-smoothness semi-infinite are tackled low-complexity manner that facilitates an alternating optimization (AO)-based iterative algorithm. The proposed algorithm divides considered problem into two subproblems. For RIS subproblem, exploit penalty convex-concave procedure (P-CCP) obtain stationary solution achieve effective initialization. successive convex approximation (SCA) is adopted convergence guarantee Karush-Kuhn-Tucker (KKT) solution. Numerical results demonstrate effectiveness design, which achieves superior performance low complexity. Moreover, importance shift for robustness advantages distributed further highlighted.

Язык: Английский

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