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Reconfigurable Intelligent Surfaces: Three Myths and Two Critical Questions [article]

Emil Björnson, Özgecan Özdogan, Erik G. Larsson
2020 arXiv   pre-print
One option is reconfigurable intelligent surfaces (RIS), which can collect wireless signals from a transmitter and passively beamform them towards the receiver.  ...  ; 2) How can we estimate channels and control an RIS in real time?  ...  RIS have also been called software-controlled metasurfaces [3] and intelligent reflecting surfaces [4] .  ... 
arXiv:2006.03377v2 fatcat:mscnhobkffczbfpgtnn64yepza

Optimization-driven Machine Learning for Intelligent Reflecting Surfaces Assisted Wireless Networks [article]

Shimin Gong, Jiaye Lin, Jinbei Zhang, Dusit Niyato, Dong In Kim, Mohsen Guizani
2020 arXiv   pre-print
Intelligent reflecting surface (IRS) has been recently employed to reshape the wireless channels by controlling individual scattering elements' phase shifts, namely, passive beamforming.  ...  These observations motivate us to design a novel optimization-driven ML framework for IRS-assisted wireless networks, which takes both advantages of the efficiency in model-based optimization and the robustness  ...  receiver Intelligent Reflecting Surface (IRS) IRS controller Active beamforming Passive beamforming x0 y0 z0 x1 y1 Passive scattering element Inter-cell communications IRS controller  ... 
arXiv:2008.12938v1 fatcat:ysrvjwwgufe4za46ryr3vhpisa

Immersive Mixed Media Augmented Reality Applications and Technology [chapter]

Volker Kuchelmeister, Jeffrey Shaw, Matthew McGinity, Dennis Del Favero, Ardrian Hardjono
2009 Lecture Notes in Computer Science  
It operates in non real-time, by employing 360º video recording instead of a live camera feed and it uses immersive projection technology, a 180º dome surface as a display environment.  ...  is situated in the iDome environment, but uses a spherical mirror as reflection surface to fill the dome.  ...  It utilizes a three meter fiberglass dome as the surface for 180° projection made possible by a High Definition projector and a spherical mirror as reflection surface [1, 2, 3] .  ... 
doi:10.1007/978-3-642-10467-1_109 fatcat:kqe6m3nhrja5foeg36tjapwdsi

Wireless Communications Through Reconfigurable Intelligent Surfaces

Ertugrul Basar, Marco Di Renzo, Julien de Rosny, Merouane Debbah, Mohamed-Slim Alouini, Rui Zhang
2019 IEEE Access  
INDEX TERMS 6G, large intelligent surfaces, meta-surfaces, reconfigurable intelligent surfaces, smart reflect-arrays, software-defined surfaces, wireless communications, wireless networks.  ...  The recent advent of reconfigurable intelligent surfaces in wireless communications enables, on the other hand, network operators to control the scattering, reflection, and refraction characteristics of  ...  In particular, different authors have used different terms to denote the RISs, which include: reconfigurable intelligent surfaces, large intelligent surfaces, smart reflect-arrays, intelligent reflecting  ... 
doi:10.1109/access.2019.2935192 fatcat:6pjbpzbisnduxfykkelv42suhi

Reconfigurable Intelligent Surfaces: Principles and Opportunities [article]

Yuanwei Liu, Xiao Liu, Xidong Mu, Tianwei Hou, Jiaqi Xu, Marco Di Renzo, Naofal Al-Dhahir
2021 arXiv   pre-print
Reconfigurable intelligent surfaces (RISs), also known as intelligent reflecting surfaces (IRSs), or large intelligent surfaces (LISs), have received significant attention for their potential to enhance  ...  Furthermore, we survey existing research contributions that apply machine learning for tackling challenges in dynamic scenarios, such as random fluctuations of wireless channels and user mobility in RIS-enhanced  ...  Reconfigurable intelligent surfaces (RISs), also called intelligent reflecting surfaces (IRSs) [3] , [4] or large intelligent surfaces (LISs) [5] , [6] , comprise an array of reflecting elements for  ... 
arXiv:2007.03435v3 fatcat:pynhymbavfhgrmqnhzjndxnthq

Wireless Communications Through Reconfigurable Intelligent Surfaces [article]

Ertugrul Basar, Marco Di Renzo, Julien de Rosny, Merouane Debbah, Mohamed-Slim Alouini, Rui Zhang
2019 arXiv   pre-print
The recent advent of reconfigurable intelligent surfaces in wireless communications enables, on the other hand, network operators to control the scattering, reflection, and refraction characteristics of  ...  intelligent surfaces in 6G and beyond wireless networks.  ...  RECONFIGURABLE INTELLIGENT SURFACES: HOW DOTHEY WORK? Fig. 4 . 4 Reconfigurable reflect-arrays with tunable resonators.  ... 
arXiv:1906.09490v2 fatcat:g37e2e7lnbgz7lhubkb3xk3wnu

Active Sensing for Communications by Learning [article]

Foad Sohrabi, Tao Jiang, Wei Cui, Wei Yu
2022 arXiv   pre-print
In particular, we consider the adaptive beamforming problem for mmWave beam alignment and the adaptive reconfigurable intelligent surface sensing problem for reflection alignment.  ...  To tackle such a challenging problem in which the dimension of historical observations increases over time, we propose to use a long short-term memory (LSTM) network to exploit the temporal correlations  ...  coefficients of an intelligent surface can be configured in order to maximize some system objective, e.g., the beamforming gain.  ... 
arXiv:2112.04075v3 fatcat:wyl4fn7ohvefzm6wjwlbmvaqmm

Deep Learning-Based Optimal RIS Interaction Exploiting Previously Sampled Channel Correlations [article]

Mehmet Ali Aygul, Mahmoud Nazzal, Huseyin Arslan
2020 arXiv   pre-print
Earlier works used estimated channel information with deep learning algorithms to design RIS reflection matrices.  ...  One of the main challenges is the configuration of reflecting coefficients without the need for beam training overhead or massive channel estimation.  ...  Reconfigurable intelligent surfaces (RISs) [3] , [4] have been proposed as a means of improving the coverage and efficiency of mMIMO systems.  ... 
arXiv:2010.10087v1 fatcat:fymqekvoyvf6fnwa4ogwymqpea

Smart Radio Environments Empowered by Reconfigurable Intelligent Surfaces: How it Works, State of Research, and Road Ahead [article]

Marco Di Renzo, Alessio Zappone, Merouane Debbah, Mohamed-Slim Alouini, Chau Yuen, Julien de Rosny, Sergei Tretyakov
2020 arXiv   pre-print
What is a reconfigurable intelligent surface? What is a smart radio environment? What is a metasurface? How do metasurfaces work and how to model them?  ...  Shannon's mathematical theory of communication with G. Green's and J. C.  ...  However, each unit element may have a complete RF chain and an independent baseband unit. • Intelligent reflecting surfaces (IRSs).  ... 
arXiv:2004.09352v1 fatcat:ncsxqispbrcdrcpyrqvja3ie3m

Reconfigurable Intelligent Surface aided Massive MIMO Systems with Low-Resolution DACs [article]

Jianxin Dai, Yuanyuan Wang, Cunhua Pan, Kangda Zhi, Hong Ren, Kezhi Wang
2021 arXiv   pre-print
We investigate a reconfigurable intelligent surface (RIS)-aided multi-user massive multiple-input multi-output (MIMO) system where low-resolution digital-analog converters (DACs) are configured at the  ...  Simulation results show that the downlink sum achievable rate tends to a constant with the increase of the number of quantization bits of DACs, and four quantization bits are enough to capture a large  ...  INTRODUCTION Recently, a reconfigurable intelligent surface (RIS), which can configure the wireless propagation environment, has attracted extensive research interests [1] - [3] .  ... 
arXiv:2103.08871v2 fatcat:bgaechjmibagxkf7uibw7vnaea

Airport Taxi Time Prediction and Alerting: A Convolutional Neural Network Approach [article]

Erik Vargo, Alex Tien, Arian Jafari
2021 arXiv   pre-print
(e.g., runway configuration, the state of aircraft in the taxiing process) is inferred implicitly and automatically by Artificial Intelligence (AI).  ...  Learning directly from surface radar information with minimal processing, a computer vision-based model is proposed that incorporates airport surface data in such a way that adaptation-specific information  ...  information (e.g., runway configuration, the state of aircraft in the taxiing process) is inferred implicitly and automatically by Artificial Intelligence (AI).  ... 
arXiv:2111.09139v1 fatcat:hltcceqb7rg2nhpuucps5caqhe

Smart Radio Environments [article]

Gabriele Gradoni, Marco Di Renzo, Ana Diaz-Rubio, Sergei Tretyakov, Christophe Caloz, Zhen Peng, Andrea Alu, Geoffroy Lerosey, Mathias Fink, Vincenzo Galdi, Tie Jun Cui, Benjamin Frazier (+18 others)
2021 arXiv   pre-print
Meta-surface modelling and design methods are reviewed along with physical realisation techniques.  ...  This Roadmap takes the reader on a journey through the research in electromagnetic wave propagation control via reconfigurable intelligent surfaces.  ...  Intelligent reflecting surfaces (IRS) can be considered a distinct form of metasurface type apertures.  ... 
arXiv:2111.08676v1 fatcat:osgcjeksmnfavolkajrr67qo6q

THE IMPACT OF LAND FORM ON URBAN IDENTITY; EL SHAMIYA PROJECT, MAKKAH, SAUDI ARABIA

Salma S. El-Esawy, Khalid S. Al-Hagla, Zeyad T. El Sayad
2016 JES. Journal of Engineering Sciences  
This area is undergoing development that affects its landform configuration.  ...  The metric for intelligibility is developed by correlating of global measure spatial configuration with a local measure.  ...  The geomorphology has determined the unique urban pattern of the Makkah metropolitan city, which has sprawled in radial direction on the confined surface areas of the complex silt channels.  ... 
doi:10.21608/jesaun.2016.117604 fatcat:jc3gv3abjveefcv5rrknlpdcye

Performance Analysis of Intelligent Reflecting Surface Assisted Opportunistic Communications [article]

L. Yashvanth, Chandra R. Murthy
2022 arXiv   pre-print
Intelligent reflecting surfaces (IRSs) are a promising technology for enhancing coverage and spectral efficiency, especially in the millimeter wave (mmWave) bands.  ...  Existing approaches to leverage the benefits of IRS involve the use of a resource-intensive channel estimation step followed by a computationally expensive algorithm to optimize the reflection coefficients  ...  INTRODUCTION Intelligent Reflecting Surfaces (IRSs) have become a topic of active research for enhancing the performance of next generation wireless communication systems, especially in the millimeter  ... 
arXiv:2203.06313v2 fatcat:6ehzud2s5nftrem2q2iwybmlta

Intelligent Reflective Surfaces for Wireless Networks: An Overview of Applications, Approached Issues, and Open Problems

Darian Pérez-Adán, Óscar Fresnedo, José P. Gonzalez-Coma, Luis Castedo
2021 Electronics  
An intelligent reflective surface (IRS) is a novel and revolutionizing communication technology destined to enable the control of the radio environment.  ...  This technology introduces the notion of a smart propagation environment with the aim of improving the system performance.  ...  In particular, two ML algorithms have been proposed, which learn the statistical CSI from the historical channel observations.  ... 
doi:10.3390/electronics10192345 fatcat:n24ysswfrbe4vlu5kfhc5yopby
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