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Uplink Non-Orthogonal Multiple Access over Mixed RF-FSO Systems [article]

Mohammad Vahid Jamali, Hessam Mahdavifar
2020 arXiv   pre-print
In this paper, we consider a relay-assisted uplink non-orthogonal multiple access (NOMA) system.  ...  This work can be considered as a general analysis of dual-hop uplink NOMA systems as well as the first attempt to incorporate power-domain NOMA in mixed RF-FSO systems.  ...  Fig. 1 . 1 Block diagram of the uplink NOMA transmission over mixed RF-FSO and dual-hop RF/RF systems.  ... 
arXiv:1903.00326v2 fatcat:eohp4d74abcffehsijvxxusww4

Outage Probability Analysis of Uplink NOMA over Ultra-High-Speed FSO-Backhauled Systems [article]

Mohammad Vahid Jamali, Seyed Mohammad Azimi-Abarghouyi, Hessam Mahdavifar
2018 arXiv   pre-print
In this paper, we consider a relay-assisted uplink non-orthogonal multiple access (NOMA) system where two radio frequency (RF) users are grouped for simultaneous transmission, over each resource block,  ...  This work can be regarded as an initial attempt to incorporate power-domain NOMA over ultra-high-speed FSO-backhauled systems, known as mixed RF-FSO systems.  ...  INTRODUCTION Non-orthogonal multiple access (NOMA) is being considered as one of the enabling technologies for the fifth generation (5G) wireless networks.  ... 
arXiv:1809.02893v1 fatcat:dzusgjtzhjdhxht7k5v3zxmrfu

Survey on Physical Layer Security in Optical Wireless Communication Systems

Mohanad Obeed, Anas M. Salhab, Mohamed-Slim Alouini, Salam A. Zummo
2018 2018 Seventh International Conference on Communications and Networking (ComNet)  
However, the security in OWC networks is still an issue, especially in visible light communication (VLC) when the transmitted information can be accessed by multiple users as in public areas, meeting rooms  ...  as a promising technology to overcome the RF spectrum limitations.  ...  There are two scenarios of mixed RF/FSO systems, which are the uplink and downlink scenarios.  ... 
doi:10.1109/comnet.2018.8622294 dblp:conf/comnet/ObeedSAZ18 fatcat:sejcybe6vverbef5m7elpxwcpy

Optical Wireless Hybrid Networks: Trends, Opportunities, Challenges, and Research Directions

Mostafa Zaman Chowdhury, Moh Khalid Hasan, Md. Shahjalal, Md. Tanvir Hossan, Yeong Min Jang
2020 IEEE Communications Surveys and Tutorials  
An RF/optical wireless hybrid system consists both RF and optical-based wireless technologies, whereas an optical/optical wireless hybrid system consists two or more types of OWC technologies.  ...  We provide a technology overview of existing literature on optical wireless hybrid networks, such as RF/optical and optical/optical systems.  ...  Hence, efficient power allocation in a mixed RF/FSO relay system is an important concern for the mixed RF/FSO relay systems.  ... 
doi:10.1109/comst.2020.2966855 fatcat:qgkoolfncjbm3cqwj7a3b7kr2i

Retrofitting FSO Systems in Existing RF Infrastructure: A Non-Zero Sum Game Technology [article]

Abderrahmen Trichili, Amr Ragheb, Dmitrii Briantcev, Maged A. Esmail, Majid Altamimi, Islam Ashry, Boon S. Ooi, Saleh Alshebeili, Mohamed-Slim Alouini
2021 arXiv   pre-print
This paper discusses installing infrared OWC, known as free space optics (FSO), systems on top of installed radio frequency (RF) networks for outdoor applications to benefit from the reliability of RF  ...  We equally review commercially available solutions and the hardware requirements for RF and FSO technology co-existence. The potential of hybrid RF/FSO for space communication is further discussed.  ...  MIXED RF/FSO MULTIHOP LINKS A possible scenario for the deployment of FSO is when it is combined with RF transmission systems to fill the connectivity gap between the RF access network and the fiber backbone  ... 
arXiv:2105.07543v1 fatcat:jhy7r6aocba2lmiw7gk7qsxesq

Ergodic Sum Rate Analysis of UAV-Based Relay Networks with Mixed RF-FSO Channels [article]

Hedieh Ajam, Marzieh Najafi, Vahid Jamali, Robert Schober
2020 arXiv   pre-print
In this work, a UAV-based communication system with radio frequency (RF) access links to the mobile users (MUs) and a free-space optical (FSO) backhaul link to the ground station (GS) is considered.  ...  In particular, the RF and FSO channels in this network depend on the UAV's positioning and (in)stability.  ...  The MUs are connected via RF access links to the UAV and by assuming frequency division multiple access (FDMA), each MU's signal is assigned to an orthogonal subchannel.  ... 
arXiv:2001.00871v2 fatcat:tlpmkmpdcnamxaerfa4nefe6gi

C-RAN with Hybrid RF/FSO Fronthaul Links: Joint Optimization of RF Time Allocation and Fronthaul Compression [article]

Marzieh Najafi, Vahid Jamali, Derrick Wing Kwan Ng, Robert Schober
2018 arXiv   pre-print
This paper considers the uplink of a cloud radio access network (C-RAN) comprised of several multi-antenna remote radio units (RUs) which compress the signals that they receive from multiple mobile users  ...  To enable reliable high rate fronthaul links, we employ a hybrid radio frequency (RF)/free space optical (FSO) system for fronthauling.  ...  In this paper, we consider the uplink of a C-RAN with RF multiple-access links and hybrid RF/FSO fronthaul links.  ... 
arXiv:1808.05004v1 fatcat:r2tek5d7djgurcwrbsgrrpka5q

Ergodic Sum Rate Analysis of UAV-Based Relay Networks with Mixed RF-FSO Channels

Hedieh Ajam, Marzieh Najafi, Vahid Jamali, Robert Schober
2020 IEEE Open Journal of the Communications Society  
In this work, a UAV-based communication system with radio frequency (RF) access links to the mobile users (MUs) and a free-space optical (FSO) backhaul link to the ground station (GS) is considered.  ...  In particular, the RF and FSO channels in this network depend on the UAV's positioning and (in)stability.  ...  The MUs are connected via RF access links to the UAV and by assuming frequency division multiple access (FDMA), each MU's signal is assigned to an orthogonal subchannel.  ... 
doi:10.1109/ojcoms.2020.2969492 fatcat:byb7h4gesbgtlmne7vhbbpavy4

Table of contents

2020 IEEE Transactions on Communications  
Jiao 3667 Optical Communication On the Effect of Interference and Misalignment Error in Mixed RF/FSO Systems Over Generalized Fading Channels ...........................................................  ...  Hanzo 3311 Cooperative/Relay Systems Finite Blocklength Non-Orthogonal Cooperative Communication Relying on SWIPT-Enabled Energy Harvesting Relays ......................................................  ... 
doi:10.1109/tcomm.2020.2995215 fatcat:ijly7cxe5zafrjyuk2i73x4r2u

Table of contents

2019 IEEE Communications Letters  
B. da Costa 1497 Outage Performance Analysis for SWIPT-Based Cooperative Non-Orthogonal Multiple Access Systems .............. ..........................................................................  ...  Lu 1547 OPTICAL COMMUNICATIONS Interference-Limited Mixed MUD-RF/FSO Two-Way Cooperative Networks Over Double Generalized Gamma Turbulence Channels .....................................................  ... 
doi:10.1109/lcomm.2019.2936058 fatcat:634t3zppnnhnbev45tdatfnfeu

Table of contents

2020 IEEE Open Journal of the Communications Society  
Schober 477 On the Performance of Dual-Hop Systems Over Mixed FSO/mmWave Fading Channels Y. Zhang, J. Z, L. Yang, B. A, and M.-S.  ...  Chen Communication Theory and Systems 164 Ergodic Sum Rate Analysis of UAV-Based Relay Networks With Mixed RF-FSO Channels H. Ajam, M. Najafi, V. Jamali, and R.  ... 
doi:10.1109/ojcoms.2020.3045657 fatcat:ujiihquwrva2pfy6psdoqhn6oa

2020 Index IEEE Transactions on Wireless Communications Vol. 19

2020 IEEE Transactions on Wireless Communications  
., Joint Access and Backhaul Resource Management in Satellite-Drone Networks: A Competitive Market Approach; TWC June 2020 3908-3923 Hu, Y.H., see Xia, M., TWC June 2020 3769-3781 Hua, C., see Li, M  ...  2020 650-664 Huang, A., see He, H., TWC Dec. 2020 7881-7896 Huang, C., Molisch, A.F., He, R., Wang, R., Tang, P., Ai, B., and Zhong, Z., Machine Learning-Enabled LOS/NLOS Identification for MIMO Systems  ...  ., +, TWC Jan. 2020 410-422 Uplink Non-Orthogonal Multiple Access Over Mixed RF-FSO Systems.  ... 
doi:10.1109/twc.2020.3044507 fatcat:ie4rwz4dgvaqbaxf3idysubc54

LIGHTNETs: Smart LIGHTing and Mobile Optical Wireless NETworks — A Survey

Abdullah Sevincer, Aashish Bhattarai, Mehmet Bilgi, Murat Yuksel, Nezih Pala
2013 IEEE Communications Surveys and Tutorials  
Recently, rapid increase of mobile devices pushed the radio frequency (RF)-based wireless technologies to their limits.  ...  Though stemming from the same core technology, the smart lighting and FSO communication have inherent tradeoffs amongst each other.  ...  They achieved an uplink increase up to 154% over pure beam-steering and 45% over pure base station diversity.  ... 
doi:10.1109/surv.2013.032713.00150 fatcat:dv33l67lajbgbgz2bwl74l6hgy

Table of contents

2020 IEEE Transactions on Communications  
Arias-De-Reyna 2740 2922 Non-Orthogonal Multiple Access for Air-to-Ground Communication ............... X. Mu, Y. Liu, L. Guo, and J.  ...  Liu 2992 Optical Communication Secure Cooperative Transmission for Mixed RF/FSO Spectrum Sharing Networks ........................................ ......................................................  ... 
doi:10.1109/tcomm.2020.2987509 fatcat:ghmoii5qfvegjg7jtpdblyejry

A Survey of NOMA for VLC Systems: Research Challenges and Future Trends

Hesham Sadat, Mohamed Abaza, Ali Mansour, Ayman Alfalou
2022 Sensors  
The power domain nonorthogonal multiple access (PD-NOMA) scheme is envisioned to address several challenges in VLC systems. In this paper, we present a detailed overview of PD-NOMA based VLC systems.  ...  Visible light communication (VLC) has become a promising technology for high data rate communications and an attractive complementary to conventional radio frequency (RF) communication.  ...  Multiple Access Techniques in RF Multiple access techniques used in VLC systems are adopted from their counterparts in RF communication systems [2] .  ... 
doi:10.3390/s22041395 pmid:35214296 pmcid:PMC8962994 fatcat:qhjvxjkt2jcptm7cfsyot6wk6u
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