EMF-Aware Cellular Networks in RIS-Assisted Environments

Ibraiwish, Hussam; Elzanaty, Ahmed; Al-Badarneh, Yazan H.; Alouini, Mohamed‐Slim

doi:10.1109/lcomm.2021.3120688

Cited by 30 publications

(25 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, in 5G and beyond networks, the adopted millimeter-waves (mm-Waves) are subject to high blockage of the line of sight (LoS) signal in unfavorable channel conditions, and it suffers from high path loss. Recently, reconfigurable intelligent surfaces (RISs), which can reflect the incident electromagnetic wave toward the specified direction, have been proposed to reduce exposure [12]. However, in order to operate on a large scale, several RISs need to be installed and optimized jointly, which can be a challenging task.…”

Section: A Related Workmentioning

confidence: 99%

“…Although the use of fixed deployed SCs and RISs can effectively reduce EMF exposure, the network cannot adapt to user distribution changes [12], [16]. Therefore, a more flexible deployment with airborne-SCs can assist the existing cellular infrastructure to provide users with better service quality, e.g., coverage and capacity [17]- [21].…”

Section: A Related Workmentioning

confidence: 99%

“…Moreover, there should be a minimal power received by gNB to satisfy the required rate, which depends on the path loss and transmit power. In fact, the transmit power should compensate for the path loss, which depends on the association between TUAVs and GSs ϑ mn , the association between users and gNBs ǫ kj , as indicated by (12). Also, the path loss depends the distance between the TUAV and the users, r kj , as in (4), which, by its turn on, depends on the tether length T m , elevation angle θ m , and azimuth angle ϕ m of the tether, as shown in Fig.…”

Section: Complete Optimization Modelmentioning

confidence: 99%

See 2 more Smart Citations

Green Tethered UAVs for EMF-Aware Cellular Networks

Lou

Elzanaty

Alouini

2021

Preprint

Self Cite

View full text Add to dashboard Cite

A prevalent theory circulating among the non-scientific community is that the intensive deployment of base stations over the territory significantly increases the level of electromagnetic field (EMF) exposure and affects population health. To alleviate this concern, in this work, we propose a network architecture that introduces tethered unmanned aerial vehicles (TUAVs) carrying green antennas to minimize the EMF exposure while guaranteeing a high data rate for users. In particular, each TUAV can attach itself to one of the possible ground stations at the top of some buildings. The location of the TUAVs, transmit power of user equipment and association policy are optimized to minimize the EMF exposure. Unfortunately, the problem turns out to be a mixed integer non-linear programming (MINLP), which is non-deterministic polynomial-time (NP) hard. We propose an efficient low-complexity algorithm composed of three submodules. Firstly, we propose an algorithm based on the greedy principle to determine the optimal association matrix between the users and base stations. Then, we offer two approaches, modified K-mean and shrink and realign (SR) process, to associate each TUAV with a ground station. Finally, we put forward two algorithms based on the golden search and SR process to adjust the TUAV's position within the hovering area over the building. After that, we consider the dual problem that maximizes the sum rate while keeping the exposure below a predefined value, such as the level enforced by the regulation. Next, we perform extensive simulations to show the effectiveness of the proposed TUAVs to reduce the exposure compared to various architectures. Eventually, we show that TUAVs with green antennas can effectively mitigate the EMF exposure by more than 20% compared to fixed green small cells while achieving a higher data rate.

show abstract

Section: A Related Workmentioning

confidence: 99%

Section: A Related Workmentioning

confidence: 99%

Section: Complete Optimization Modelmentioning

confidence: 99%

See 1 more Smart Citation

Green Tethered UAVs for EMF-Aware Cellular Networks

Lou

Elzanaty

Alouini

2021

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…To further improve the performance of the aforementioned BF schemes, [11] has also proposed to exploit the nascent concept of smart radio environments for the future 6 th generation network (6G), by shaping the propagation environment itself (according to some Channel State Information (CSI)) thanks to reconfigurable intelligent surfaces (RISs) [11]- [16]. Note that in [15] [16], RISs are used to reduce self-EMFE reduction due to the smartphone uplink, whereas [11] uses RISs for EMFE reduction in the downlink. More precisely, in [11], a RIS with continuous (instead of discrete) phase-shifting capability as in [17] [18] and sensing capability, first measures the propagation channel between the target UE and itself, and then, selfconfigures to 'turn itself electronically' in the direction of the target UE.…”

Section: Introductionmentioning

confidence: 99%

A Novel RIS-Aided EMF-Aware Beamforming Using Directional Spreading, Truncation and Boosting

Awarkeh

Phan-Huy

Visoz

et al. 2022

2022 Joint European Conference on Networks and Communications &Amp; 6G Summit (EuCNC/6G Summit)

View full text Add to dashboard Cite

This paper addresses a drawback of massive multiple-input multiple-output Maximum Ratio Transmission beamforming. In some propagation conditions, when the base station serves the same target user equipment for a long period, it reduces the transmit power (and degrades the received power) to avoid creating high exposure regions located in the vicinity of the antenna and concentrated in few directions (corresponding to the best propagation paths between the antenna and the receiver). In this paper, we propose a novel electromagnetic field aware beamforming scheme, which (i) spreads the beamforming radiation pattern in the angular domain by adding artificial propagation paths thanks to reconfigurable intelligent surfaces, (ii) truncates the pattern in strong directions, and (iii) boosts it in weak directions. Compared to existing solutions, it maximizes the received power. However, it also consumes more power. Finally, truncation alone is the best trade-off between received power and energy efficiency, under exposure constrain.

show abstract

“…where A is a matrix representing the summation of all the matrices inside the trace function in (12). So, we have the following optimization problem…”

mentioning

confidence: 99%

Wireless Network Coding with Intelligent Reflecting Surfaces

Kafizov¹,

Elzanaty²,

Varshney³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

Conventional wireless techniques are becoming inadequate for beyond fifth-generation (5G) networks due to latency and bandwidth considerations. To improve the error performance and throughput of wireless communication systems, we propose physical layer network coding (PNC) in an intelligent reflecting surface (IRS)-assisted environment. We consider an IRS-aided butterfly network, where we propose an algorithm for obtaining the optimal IRS phases. Also, analytic expressions for the bit error rate (BER) are derived. The numerical results demonstrate that the proposed scheme significantly improves the BER performance. For instance, the BER at the relay in the presence of a 32-element IRS is three orders of magnitudes less than that without an IRS.

show abstract

EMF-Aware Cellular Networks in RIS-Assisted Environments

Cited by 30 publications

References 13 publications

Green Tethered UAVs for EMF-Aware Cellular Networks

Green Tethered UAVs for EMF-Aware Cellular Networks

A Novel RIS-Aided EMF-Aware Beamforming Using Directional Spreading, Truncation and Boosting

Wireless Network Coding with Intelligent Reflecting Surfaces

Contact Info

Product

Resources

About