Telecom

It is well known that existing empirical models cannot fit perfectly into environments other than those they were formulated in due to differences in terrain and climate. The Okumura–Hata family of models are gaining acceptability over the VHF/UHF channels. However, it is imperative to investigate their reliability and to use the one most suited to each environment. This study investigated the reliability of the Okumura–Hata, COST-231, ECC-33, and Ericsson models over digital UHF channels in Ikorodu and Akure, Southwestern Nigeria. The drive test protocol was used for data collection at intervals of 1 km along different routes from the experimental stations up to maximums of 10 and 16 km in Ikorodu and Akure, respectively. This was carried out for both wet and dry season months using a digital Satlink meter with a spectrum (WS-6936), GPS Map 78s and a field vehicle. The uniqueness of this study is that it used real-world data with a seasonal scope, and the mean values were employed in the analysis to strengthen the reliability of the results. The measured path loss (MPL) and predicted path loss (PPLM) were computed, with error margin analysis carried out between them. The results reveal a mean MPL of 110.42 dB in Ikorodu, while the PPLMs were 121.90, 123.55, 158.42, and 291.01 dB for the Hata, COST-231, Ericsson, and ECC-33 models, respectively. In Akure, the mean MPL was 123.157 dB, while the PPLMs were 121.922, 130.179, 198.979, and 313.494 dB. The results further indicate that the Hata model had the best performance with the lowest RMSE of 10.812 in Ikorodu, while COST-231 had the best performance in Akure, with the lowest RMSE of 9.877. The optimized Hata and COST-231 models were developed with improved RMSEs of 5.895 and 7.815 for the Ikorodu and Akure environments, respectively. The optimized models had higher degrees of reliability and will provide a valuable approach to wireless communication planning in tropical urban and suburban environments for achieving quality of transmission and reception (QoTnR) over UHF channels in Nigeria and similar environments in Africa. Full article

As the discussions on sixth-generation (6G) wireless networks progress at a rapid pace, various approaches have emerged over the last few years regarding new architectural concepts that can support the 6G vision. Therefore, the goal of this work is to highlight the most important technological efforts in relation to the definition of a 6G architectural concept. To this end, the primary challenges are first described, which can be viewed as the driving forces for the 6G architectural standardization. Afterwards, novel technological approaches are discussed to support the 6G concept, such as the introduction of artificial intelligence and machine learning for resource optimization and threat mitigation, cell-free deployments, and novel physical layer techniques to leverage high data rates. In the same context, open-access protocols for flexible resource integration, security, and privacy protection in the 6G era, as well as the digital twin concept, are discussed as well. Finally, recent research efforts are analyzed, with an emphasis on the combination of the aforementioned aspects towards a unified 6G architectural approach. To this end, limitations and open issues are highlighted as well. Full article

In this paper, we present recent advancements in transmitter and receiver technologies for Optical Wireless Communication (OWC). OWC offers very wide license-free optical spectrum which enables very high capacity transmission. Additionally, beam-steered OWC is more power-efficient and more secure due to low divergence of light. One of the main challenges of OWC is wide angle transmission and reception because law of conservation of etendue restricts maximization of both aperture and field of view (FoV). On the transmitter side, we use Micro Electro-Mechanical System cantilevers activated by piezoelectric actuators together with silicon micro-lenses for narrow laser beam steering. Such design allowed us to experimentally demonstrate at least 10 Gbps transmission over 100° full angle FoV. On the receiver side, we show the use of photodiode array, and Indium-Phosphide Membrane on Silicon (IMOS) Photonic Integrated Circuit (PIC) with surface grating coupler (SGC) and array of SGC. We demonstrate FoV greater than 32° and 16 Gbps reception with photodiode array. PIC receiver allowed to receive 100 Gbps WDM with single SGC, and 10 Gbps with an array of SGC which had 8° FoV in the vertical angle and full FoV in the horizontal angle. Our results suggest that solutions presented here are scalable in throughputs and can be adopted for future indoor high-capacity OWC systems. Full article

The Internet plays a vital role in the exchange of information in society. Maintaining the security and robustness of the Internet anomaly detection in Border Gateway Protocol (BGP) traffic is very important so that stable routing services can be ensured. The existing solutions are based on the classical machine learning (ML) models, which need to be advanced. In this study, a revolutionary technique that utilizes the Extreme Learning Machine (ELM) to enhance the detection of anomalies in the dynamic environment of the Border Gateway Protocol (BGP), particularly when faced with highly imbalanced class distributions, was used. The combination of imbalanced class distribution and BGP’s dynamic nature often leads to the suboptimal performance of classifiers. Our proposed solution aims to address this imbalance issue by dividing the dominant classes into multiple sub-classes. This division is achieved through optimal partitioning (OP), which involves segmenting the samples from the majority class into different segments to approximate the size of the minority class. As a result, diversified classes are created to train the ELM classifier. In order to assess the effectiveness of the proposed (OP-ELM) model, the RIPE and BCNET datasets were utilized. These trace files were processed using MATLAB to extract and organize the necessary features, thereby generating suitable datasets for analysis, which are referred to as Dataset-1 and Dataset-2. The experimental findings exhibit noteworthy improvements in performance when contrasted with prior methodologies, thereby highlighting the efficacy of our innovative approach in tackling the obstacles associated with anomaly detection in BGP networks. Full article

With the advances of Radio Access Networks, the Open RAN introduced the concept of virtualization and openness to the mobile network elements. These characteristics allow multi-vendor implementations in commercial out-of-shelf hardware with open radio interfaces beyond flexibility and scalability, permitting bringing the data processing to the network edge and easy network element escalation. In Brazil, Radio Access Networks comprise distributed and centralized architectural topology types, which do not meet the requirements of the 5G New Radio wireless mobile network. To reach the 5G needs, an upgrade in the existing network is necessary, revealing some challenges over the existing scenario. This study shows the state-of-art, political, and economic factors that challenge the implementation of Open RAN in Brazil, analyzing the actual regulatory and political facts that can make the technology affordable and possible to introduce quickly to the market. Full article

The potential consequences of interference on communication networks are one of the main challenges in the nature and efficiency of wireless communication links. The interruption is seen as additional noise to the device, which can have a major impact on the efficiency of the connection. The rapid expansion of broadband wireless networks and the increasing congestion of the radio frequency spectrum due to shared usage by terrestrial and satellite networks have heightened concerns about potential interference. To optimize spectrum utilization, multiple terrestrial and satellite networks often coexist within the same frequency bands allocated for satellite communications services. Spectrum interference in wireless networks is a topic of much interest in the current scenario as it can present a lot of challenges. This article provides a critical review of the coexistence and spectrum sharing in wireless networks. Along with this, mitigation techniques to avoid interference have also been discussed in detail. The article aims to give a detailed discussion on the challenges and opportunities in this field by reviewing significant recent works in this field. Full article

The design of wideband multi-port multiple-input multiple-output (MIMO) antennas and their optimization are very important for next-generation smartphones with the increase in massive connectivity. This paper offers the design, simulation, measurement, and specific absorption rate (SAR) analysis of a Pi-shaped ten-element MIMO antenna system for use in the upper mid-band, covering LTE 46 (5.15–5.925 GHz), LTE 47 (5.855–5.925 GHz), and n102 (5.925–6.425 GHz), thus meeting a good fractional bandwidth of 32.7% with a maximum peak gain of 2.89 dBi. Hence, it is well suited for high-isolation (<−10 dB), compactness, and wideband (4.7–6.5 GHz) applications suitable for the current communication system needs. The overall size of the proposed system is 125 mm × 70 mm, with a planar dielectric material Rogers RT/5880. Designing the proposed antenna with multiple units entails the preservation of the spatial features of the antenna alongside the reduction of the mutual coupling for adjacent elements by using a decoupling structure. Due to the high accuracy of the positioning elements and precise geometric transformations, the antenna system provides high-performance analysis based on reflection coefficients, radiation patterns, and each antenna’s averaged efficiency values (76.12–91.57%). Full article

Advances in telecommunications and artificial intelligence (AI) are reshaping modern educational spaces. Drawing upon diverse resources, this systematic literature review examines how these new advances including 5G, Internet of Things (IoT), and AI-based analytics can transform conventional classrooms into adaptive, secure, and highly interactive environments. Real-time data collection and personalized feedback systems are found to significantly enhance engagement and accessibility for diverse learner populations. Furthermore, emerging security architectures, such as zero-trust frameworks and AI-driven intrusion detection, mitigate cyber threats and strengthen data confidentiality. Nevertheless, it is found that broader adoption is limited due to practical hurdles, which include budget allocation, professional development, and regulatory compliance. In response, strategic recommendations are provided to guide the planning and implementation of intelligent telecommunications in different educational contexts while noting the need for responsible data governance and equitable access. By illustrating how AI-assisted connectivity can enhance personalized instruction while safeguarding learner privacy, this study offers a forward-looking perspective on modern pedagogical approaches which can balance technological innovation with ethical considerations. Full article

The inherent characteristics of blockchain, including immutability, self-execution, and the removal of intermediaries, consistently generate increasing interest in its applications within the telecom sector, making it an exciting area for investment. This literature review aims to explore a promising research area known as blockchain interoperability. Interoperability seeks to connect two or more independent blockchains to effectively exchange information. Through leveraging the interoperability features of blockchain, independent telecom networks can seamlessly share information with other mobile, fixed, and next-generation networks. This results in improved security and efficiency, cost savings, and an enhanced customer experience. This study reviews highly cited research papers in the literature to assess blockchain’s relevance to telecom use cases for interoperability. Additionally, it presents prominent interoperability solutions and identifies essential requirements for the successful implementation of blockchain interoperability in the telecom sector. The findings highlight key research gaps and future directions for the adoption of blockchain in telecommunications, particularly for the forthcoming sixth generation (6G). Full article

6G is expected to provide ubiquitous connectivity, particularly in remote and inaccessible environments, by integrating satellite and aerial networks with existing terrestrial networks, forming Space–Air–Ground Integrated Networks (SAGINs). These networks, comprising satellites, unmanned aerial vehicles (UAVs), and high-speed terrestrial networks, introduce severe Doppler effects due to high mobility. Traditional modulation techniques like Orthogonal Frequency Division Multiplexing (OFDM) struggle to maintain reliable communication under such conditions. This paper investigates Orthogonal Time Frequency Space (OTFS) modulation as a robust alternative for high-mobility scenarios in SAGINs. Using 6G exploration library in MATLAB, this study compares the bit error rate (BER) performance of OTFS and OFDM under static and multipath channels with varying mobility scenarios from 20 km/h to 2000 km/h, and varying modulation orders (BPSK, QPSK, and 8-PSK). The results indicate that OTFS significantly outperforms OFDM, while maintaining signal integrity under extreme mobility conditions. OTFS modulates information symbols in the delay–Doppler domain, demonstrating a strong robustness against Doppler shifts and delay spreads. This makes it particularly suitable for high-mobility applications such as satellites, UAVs, and high-speed terrestrial networks. Conversely, while OFDM remains effective in static and low-mobility environments, it struggles with severe Doppler effects, common in the proposed SAGINs. These findings reinforce OTFS as a promising modulation technique for SAGINs in 6G and beyond. Full article

This study presents an innovative Dual-Band Frequency Selective Surface (FSS) designed for LTE applications, offering an effective solution for minimizing Passive Inter-Modulation (PIM) in contemporary wireless communication systems at the base station. The proposed passband FSS filter is designed to deliver optimal dual-band filtering characteristics with consistent stability over incidence angles up to 80°. Corresponding to antenna systems requirements, the proposed method gives resonant frequencies at 1.9 and 2.1 GHz which operate in the LTE band with bandwidths of 40 and 60 MHz, respectively. Moreover, the proposed design is analyzed to establish the optimal range for each resonant frequency by examining the parametric effects. The suggested FSS-based filter consists of a single-layer structure with the dimension of the unit cell of 0.33${\lambda }_1$ × 0.33${\lambda }_1$ where ${\lambda }_1$ is the wavelength of low frequency, which delivers desired reflection and transmission coefficients using RT/Duroid 5880 with a thickness of 0.508 mm. The designed filter is validated through measurements of a fabricated prototype, demonstrating its practicality and performance. Simulations carried out with Equivalent Circuit Modeling (ECM) are demonstrated by measurements from a constructed 4 × 4 array prototype, showing a robust alignment with experimental findings. This work emphasizes an asymmetric FSS design that improves frequency selectivity and angular stability for the desired LTE dual band and also depicts the future possibilities for tuneable models and broader applications to meet the demands of modern wireless communication. Full article

Consumer behavior has changed considerably over time. In recent decades, people have used resources at a rate that exceeds the total consumed throughout history. This paper aims to address the determinants of the smartphone purchase decision, emphasizing gender differences, price influence, and previous online shopping experience. The methodology used combines a bibliometric review of the literature to identify major trends in consumer behavior research and a quantitative research survey that provides insight into consumer behavior in the smartphone purchase process. The survey highlights brand preferences, purchase patterns, product selection criteria, and the influence of socioeconomic factors on the purchase decision, identifying the determinants of online versus physical store purchase decisions among young consumers in the northeastern, east, and southeastern regions of Romania. Thus, our analysis aims to identify the variables influencing consumer preferences and to assess the statistical significance of these differences using quantitative methods and relevant statistical tests. The collected data came from a valid sample of 456 respondents for the general analysis and 271 valid cases for the online shopping analysis. The analysis shows that gender is a significant predictor of online purchase decisions, with men being 2.65 times more likely to purchase a smartphone online than women. The collected data were analyzed using t-tests, Chi-square tests, and logistic regression to assess the influence of variables on online smartphone purchase intention. Full article

The everyday comfort and security of the present society are intimately associated with the assistance of different tools that function by means of diverse sources linked to the transfer and conversion of electromagnetic (EM) energy. The use of these devices exhibits expected outcomes, which are regularly coexistent with unwanted side effects. A laudable intention of an administration is to strengthen the anticipated results and lessen the unsolicited effects. This paper’s goal, in the framework of such an organization, is to evaluate the significance of the methodologies of responsible attitude (RA) and one health (OH) in the everyday exercise of the involved wireless EM energy tools in the environment of a smart city (SC). The approach of RA is linked to a tool’s eco-design, while the concept of OH is linked to the protection of an SC’s biodiversity and ecosystem. The unwanted side effects of these wireless devices could be implicated as occurrences of straying or radiated EM fields on devices or living tissues. The investigation intends to assess the enhancement of projected outcomes and the reduction of unwanted effects in the quotidian exercise of wireless EM energy transfer and transmission tools in the SC environment. The challenges are associated with the sources and the emissions of wireless EM technologies available today, and their impacts on the health of living tissues, biodiversity, and the ecosystem. The paper centered particularly on two cases engaged in the SC environment. The first involves the disrupting effects of EM exposure of onboard or near-living tissues from sensing and assistance medical tools. The second is linked to the adverse biological effects resulting from wireless inductive power transfer used for charging the batteries inside electric vehicles while motionless or running in SCs. The inquiries followed in the paper are supported by instances in the literature. Full article

Fingerprinting-based positioning exploiting in two dimensions the spatial side information on fingerprints from adjacent positions relative to a target position is studied. The positioning is performed at the positioning device, utilizing as fingerprints the received signal strengths of downlink radio signals, collected using a two-dimensional sensor array. The motivation is to minimize the positioning error by transferring the complexity and cost from the infrastructure to the positioning device. The goal is to learn whether spatial side information on the fingerprints can minimize the positioning error. We provide a differentiation between fingerprinting in uplink and downlink, a classification of the positioning data aggregation domains, concepts, and a related literature review. We present three pattern-matching methods for estimating the position using spatial side information, two based on regression, implemented using feedforward neural networks, and one based on classification of the fractions of the positioning area, implemented using a convolutional neural network. Fingerprinting with and without spatial side information is benchmarked using the proposed pattern-matching methods in a system simulator based on Monte Carlo methods, generating synthetic fingerprints with an indoor radio channel model and calculating the positioning error. It is observed that for the given assumptions and the system considered, fingerprinting-based positioning with spatial side information substantially reduces the positioning error. Full article

This work introduces a high-performance multi-input multi-output (MIMO) antenna design to operate at the 28 GHz band. The proposed four-port MIMO antenna, in which each port comprises a 1 × 8 series-fed array, achieves peak gains of 13 dBi along with bandwidths of 1 GHz. Enhanced antenna performance is achieved through the optimal spacing of antenna elements and a decoupling methodology comprising a well-designed metamaterial unit cell, leading to reduced interference between antenna arrays. The design shows significantly suppressed mutual coupling to be less than −40 dB, a diversity gain that is very close to 10 dB, an envelope correlation coefficient of 0.00012, and a channel capacity loss of 0.147 bit/s/Hz, at 28 GHz. The experimental assessments confirmed these developments, endorsing the suggested design as a robust contender for 5G mmWave communications. Full article

As the automotive industry moves toward fully autonomous driving, the goal is to enable vehicles to operate safely without human control in all environments. Implementing Vehicle-to-Everything (V2X) communications in highway environments poses considerable challenges. Several critical services have strict network performance requirements as they deal with safety features. Existing fifth-generation (5G) base station schedulers do not discriminate among critical and non-critical automated driving functions. Therefore, in cases of increased traffic load, there is a significant drop in their performance, and, consequently, increased risk for accidents. Our paper discusses these issues and provides an adaptive scheduler called SOVANET+. The new scheduler acknowledges the Radio Access Network (RAN) load, and the requirements of critical, automated driving applications, together with channel quality, and optimizes the allocation of resources to critical services. The performance of SOVANET+ is evaluated through extensive simulations in the highway environment, an area less examined than urban scenarios. Results indicate that the adoption of SOVANET+ presents clear advantages to critical services compared to existing solutions. Full article

Device-to-Device (D2D) communication is a promising technological innovation that is significantly considered to have a substantial impact on the next generation of wireless communication systems. Modern wireless networks of the fifth generation (5G) and beyond (B5G) handle an increasing number of connected devices that require greater data rates while utilizing relatively low power consumption. In this study, we present joint mode selection, channel assignment, and power allocation issues in a semi-distributed D2D scheme (SD-scheme) that underlays cellular networks. The objective of this study is to enhance the data rate, Spectrum Efficiency (SE), and Energy Efficiency (EE) of the network while maintaining the performance of cellular users (CUs) by creating a threshold of data rate for each CU in the network. Practically, we propose a centralized approach to address the mode selection and channel assignment problems, employing greedy and matching algorithms, respectively. Moreover, we employed a State-Action-Reward-State-Action (SARSA)-based reinforcement learning (RL) algorithm for a distributed power allocation scheme. Furthermore, we suggest that the sub-channel of the CU is shared among several D2D pairs, and the optimum power is determined for each D2D pair sharing the same sub-channel, taking into consideration all types of interferences in the network. The simulation findings illustrate the enhancement in the performance of the proposed scheme in comparison to the benchmark schemes in terms of data rate, SE, and EE. Full article

The Border Gateway Protocol (BGP) is the backbone of inter-domain routing on the internet, but its susceptibility to both benign and malicious anomalies creates substantial risks to both network reliability and security. In this study, we present a new approach for deep learning-based BGP anomaly detection utilizing duplicate announcements, which are known to be a symptom of routing disruptions. We developed our methodology based on public BGP data from RIPE and Route Views. We used the number of duplicate announcements as a baseline against which we checked for sporadic and time-based anomalies. Here, we propose a deep learning framework based on the Exponential Moving Average (EMA) model in combination with Autoencoder for anomaly identification. We also apply the Temporal-oriented Synthetic Minority Over-Sampling Technique (T-SMOTE) to overcome data imbalance. Comparative evaluations show that the Autoencoder model is significantly better than LSTM and that existing state-of-the-art methods have higher accuracy, precision, recall, and F1 scores. This study proposes a reliable, scalable, and rapid framework for real-time BGP adversary detection, which improves network security and resilience. Full article

Vehicle-to-vehicle (V2V) channels exhibit highly dynamic and non-stationary characteristics, posing significant challenges in designing reliable communication systems. The level crossing rate (LCR) and average fade duration (AFD) are two important second-order statistical properties that help characterize these rapid channel changes. This paper presents an in-depth analysis of the LCR and AFD for a two-dimensional non-isotropic scattering model of a V2V Rician flat fading channel. The study investigates the influence and impact of several key parameters on LCR and AFD, focusing on the impact of high vehicle traffic density (VTD). The results closely align with available empirical data and offer valuable insights into designing robust V2V communication systems that can adapt to the rapidly evolving channel conditions. Full article