Osama Elgarhy

Osama Elgarhy


Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 February 2024 in IEEE Access
Verified
Journal Article
Open access
OEOsama Elgarhy
Osama Elgarhy
LRLuca Reggiani
Luca Reggiani
MAMuhammad Alam
Muhammad Alam
AZAhmed Zoha
Ahmed Zoha
RARizwan Ahmad
Rizwan Ahmad
AKAlar Kuusik
Alar Kuusik
The Internet of Things (IoT) is an essential part of 5G, Beyond-5G (B5G), and 6G systems; it has several applications in two of the principal 5G use cases, namely ultra-reliable low-latency communications (URLLC) and massive machine-type communications (mMTC), and in their successors within B5G and 6G: extreme ultra-reliable low-latency communication (eURLLC) and ultra-massive machine-type communication (umMTC). IoT systems, which are characterized by narrow bandwidths, have stringent requirements owing to the specific nature of their applications and use cases. The purpose of this study is to investigate and jointly optimize the energy efficiency (EE) and latency through resource allocation for IoT cellular systems. With regard to the contributions, in this study we investigated the optimization of EE in narrowband IoT systems, compared resource unit configurations (RUCs), jointly formulated the optimization of EE and latency, and introduced a suboptimal but efficient algorithm. More precisely, as the EE performance of various resource unit configurations has not been exhaustively investigated in the current state of the art, we analyzed and compared the EE of RUCs. The results show vast differences in performance between RUCs. For example, in terms of EE, the best RUC has an EE more than 80 times higher than the worst, which illustrates the importance of this investigation. We then proposed a scheduler based on the shortest job first (SJF) for minimum latency allocation, and another scheduler based on a joint evaluation of EE and latency. With respect to conventional techniques, these schedulers achieve a better trade-off between latency reduction and gain in terms of EE for a wider range of parameter configurations in multi-cellular layouts. The study demonstrates that in the presence of repetitions, algorithms that achieve high EE will mostly achieve low latency.

18 May 2020 in IEEE Systems Journal
Verified
Journal Article
Closed access
OEOsama Elgarhy
Osama Elgarhy
LRLuca Reggiani
Luca Reggiani
HMHassan Malik
Hassan Malik
MAMuhammad Alam
Muhammad Alam
Muhammad ImranMuhammad Imran
Muhammad Imran
Narrowband Internet of Things (NB-IoT) is a cellular IoT communication technology standardized by 3rd Generation Partnership Project (3GPP) for supporting massive machine type communication and its deployment can be realized by a simple firmware upgrade on existing long term evolution (LTE) networks. The NB-IoT requirements in terms of energy efficiency, achievable rates, latency, extended coverage, make the resource allocation, in a limited bandwidth, even a more challenging problem w.r.t. to legacy LTE. The allocation, done with subcarrier (SC) granularity in NB-IoT, should maintain adequate performance for the devices while keeping the power consumption as low as possible. Nevertheless, the optimal solution of the resource allocation problem is typically unfeasible since nonconvex, NP-hard and combinatorial because of the use of binary variables. In this article, after the formulation of the optimization problem, we study the resource allocation approach for NB-IoT networks aiming to analyze the tradeoff between rate and latency. The proposed suboptimal algorithm allocates radio resource (i.e., SCs) and transmission power to the NB-IoT devices for the uplink transmission and the performance is compared in terms of latency, rate, and power. By comparing the proposed allocation to a conventional round robin (RR) and to a brute-force approach, we can observe the advantages of the formulated allocation problem and the limited loss of the suboptimal solution. The proposed algorithm outperforms the RR by a factor 2 in terms of spectral efficiency and, moreover, the study includes techniques that reduce the dropped packets from 29% to 1.6%.

7 October 2021 in IEEE Systems Journal
Verified
Journal Article
Closed access
CMCollins Burton Mwakwata
Collins Burton Mwakwata
OEOsama Elgarhy
Osama Elgarhy
MAMuhammad Alam
Muhammad Alam
Yannick Le MoullecYannick Le Moullec
Yannick Le Moullec
SPSven Parand
Sven Parand
KRKostas Ramantas
Kostas Ramantas
The fifth-generation (5G) and beyond 5G (B5G) wireless networks introduced massive machine-type communications (mMTC) to cope with the growing demand of massive Internet of Things (IoT) applications. However, the heterogeneous characteristics of massive IoT and diverse quality of service (QoS) requirements may lead to severe interference that could degrade the expected QoS of the cellular ecosystem. Therefore, this article studies the impact of interference caused by mMTC connections. We theoretically model the intercell interference (ICI) minimization problem for the existing orthogonal multiple access (OMA) technique and propose its corresponding solution. Furthermore, we jointly solve the ICI and the cochannel interference minimization problem for the IoT users when the nonorthogonal multiple access (NOMA) technique is used. For the proposed OMA and NOMA schemes, we design a cooperative scheduler to reduce the impact of such interference. The results show that our proposed schemes provide up to 58%, 75%, and 100% more improvements in terms of user’s data rates, energy consumption, and connection density, respectively.

12 November 2024 in IEEE Open Journal of Vehicular Technology
Verified
Journal Article
Open access
OEOsama Elgarhy
Osama Elgarhy
Yannick Le MoullecYannick Le Moullec
Yannick Le Moullec
LRLuca Reggiani
Luca Reggiani
MAMuhammad Moazam Azeem
Muhammad Moazam Azeem
TTTarik Taleb
Tarik Taleb
MAMuhammad Alam
Muhammad Alam
In this paper, the goal is to reduce the time needed for the placement and migration of services of Connected Automated Vehicles (CAVs) using precise hybrid positioning method. First, to place a service in a Multi-access Edge Computing (MEC) node, there should be sufficient resources in the served MEC node; otherwise, the service would be placed on the neighboring MEC node or even on the core node, resulting in higher delays. We start by modeling our problem with the aid of traffic theory to analytically obtain the necessary number of resources for achieving the desired delay. Second, to reduce the migration process delay, the migration should begin before the vehicle reaches the MEC node. Thus, an AI lane-based scheme is proposed to predict candidate nodes for migration based on precise positioning. Precise positioning data is acquired from a Real-Time Kinematic Global Navigation Satellite System (RTK- GNSS) measurement campaign. The obtained imbalanced raw data is treated and used in the prediction scheme, and the resulting prediction accuracy achieves 99.3%. Finally, we formulate a service placement and migration delay optimization problem and propose an algorithm to solve it. The algorithm shows a latency reduction of approximately 50% compared to the core placement and up to 29% compared to the benchmark prediction algorithm. Moreover, the simulation results for the proposed service placement and migration algorithm show that in case the MEC resource calculations are not used, the delay is 2.2 times greater than when they are used.

27 September 2023 in Sensors
Verified
Journal Article
Open access
PDF file
OEOsama Elgarhy
Osama Elgarhy
MAMuhammad Alam
Muhammad Alam
ATAnet Tammets
Anet Tammets
PRPriit Roosipuu
Priit Roosipuu
GAGuntis Ancāns
Guntis Ancāns
PSPriit Soom
Priit Soom
Performing 5G coverage planning across borders introduces real-life challenges related to legalities, intercountry agreements, and binding documents. This work provides RF network modelling exercise results to provide uninterrupted 5G coverage to the Via Baltica and Rail Baltica transport corridors crossing Estonia and Latvia and on the border with Lithuania, as well as the Tallinn–Tartu–Valga and Valka–Valga roads (Latvia–Estonia), capable of cross-border 5G services. The study starts by identifying and interviewing stakeholders from different sectors of operation in the Baltic states and Europe and then provides an overview of some of the main legal acts and documents regulating the electronic communications sector in the Baltic states and Europe. Furthermore, 5G network requirements are proposed. In addition, the necessary and existing passive and active infrastructure is described, including spectrum management-related analysis, where the RF bands 700 MHz and 3500 MHz are analysed. Finally, coverage planning is performed. The network modelling results aim to foresee the number of new sites that need to be built on the said transport corridors, also examining the existing infrastructure for such purposes. Additionally, an estimated timeline for building the new sites is provided.

30 January 2026 in IEEE Transactions on Green Communications and Networking
Verified
Journal Article
Closed access
ALAamir Latif
Aamir Latif
OEOsama Elgarhy
Osama Elgarhy
Nurul Huda MahmoodNurul Huda Mahmood
Nurul Huda Mahmood
Yannick Le MoullecYannick Le Moullec
Yannick Le Moullec
MAMuhammad Alam
Muhammad Alam
This paper proposes a scalable and energy-efficient scheduling framework tailored for massive machine-type communications (mMTC) in future 6G networks. Motivated by the dual challenges of massive connectivity and strict energy constraints, we introduce a new cooperative multi-cell uplink scheme that jointly optimizes user scheduling, power allocation, and interference management under finite block length (FBL) constraints. While prior studies have explored energy efficiency (EE) or connectivity separately, they often neglect FBL effects and lack scalable, interference-aware coordination across multi-cell NOMA deployments. Leveraging non-orthogonal multiple access (NOMA), our framework addresses both intra- and intercell interference through a multi-objective optimization problem that simultaneously maximizes EE and connectivity. To solve the problem, we develop the Sustainable and Reliable Scheduling for Massive Machine Type Communication using NOMA (SRS-MTCN) algorithm, integrating channel-aware user clustering, interference-aware resource allocation, and iterative power optimization. Simulation results demonstrate that the proposed approach performs significantly better than state-of-the-art baselines in dense deployments, achieving up to 35 – 58% EE improvement in medium-density regimes (16 – 32 devices/m2), while ensuring robust scalability and reliability in ultra-dense scenarios exceeding 40 devices/m2. These results illustrate its suitability for sustainable 6G mMTC networks operating under FBL and energy constraints.