Search

This paper analyzes the quantitative quality parameters of a mobile communication network in a controlled drone logistic use-case scenario. Based on the analysis of standards and recommendations, the values of key performance indicators (KPIs) are set. As the main network-impacting parameters, reference signal received power (RSRP), reference signal received quality (RSRQ), and signal to interference and noise ratio (SINR) were selected. Uplink (UL), downlink (DL), and ping parameters were chosen as the secondary ones, as they indicate the quality of the link depending on primary parameters. The analysis is based on experimental measurements performed using a Latvian mobile operator's "LMT" JSC infrastructure in a real-life scenario. To evaluate the altitude impact on the selected network parameters, the measurements were performed using a drone as transport for the following altitude values: 40, 60, 90, and 110 m. Network parameter measurements were implemented in automatic mode, allowing switching between LTE4–LTE2 standards, providing the opportunity for more complex analysis. Based on the analysis made, the recommendations for the future mobile networks employed in controlled drone flights should correspond to the following KPI and their values: −100 dBm for RSRP, −16 dB for RSRQ, −5 dB for SINR, 4096 kbps for downlink, 4096 kbps for uplink, and 50 ms for ping. Lastly, recommendations for a network coverage digital twin (DT) model with integrated KPIs are also provided. [ABSTRACT FROM AUTHOR]

With the surge in mobile data traffic, leveraging Wi-Fi has become pivotal to alleviate the strain on LTE networks. An essential challenge lies in selecting the optimal Wi-Fi access point during Handover (HO), impacting Quality of Experience (QoE) and connection stability. This study introduces an innovative approach to enhance VoIP call Quality of Service (QoS) during HOs from LTE to Wi-Fi. Our contribution integrates two Mean Opinion Score (MOS) prediction models, multilayer perceptron (MLP) and recurrent neural networks (LSTMs) into the software-defined network controller (SDN), optimized by the Grey Wolf Optimizer (GWO). This solution provides accurate predictions for the SDN to forward mobile devices (MEs) and traffic to the nearest optimal Wi-Fi access points. Simulation results affirm the effectiveness of our approach. The LSTM-based approach performs well in the long run and provides better stability in terms of QoS parameters, especially when the metric of choice for mobile users is based on the Signal-to-Noise and Interference Ratio (SNIR), rather than the Received Signal Strength (RSSI) indicator. These results explore opportunities for the real-world deployment of the implemented models, particularly in urban areas experiencing cellular network congestion. [ABSTRACT FROM AUTHOR]

Network-based architectures provide accessibility to various hardware elements and information. The Vehicle to Vehicle (V2V) protocol is a Wi-Fi-based communication that potentially exposes the system to a variety of vulnerabilities. Automotive electronics is a rapidly evolving field that combines numerous machine learning algorithms, dependable communication protocols, and precise image processing techniques to create a user-friendly and self-driving autonomous car. A generic network communication vulnerability assessment method is used to undertake a navigational attack against connected vehicles using GPS falsification. This study emphasizes the security risks of using Wi-Fi for V2V (vehicle 2 vehicle) communication without suitable access control measures in place. The tool used for establishing V2V Communication is based on Kali Linux. The breakdown of vulnerabilities within each layer, such as eavesdropping, spoofing, and Malevolent intermediary strike, highlights the diverse range of potential threats vehicles might face. The focus on the communication layer, both within the vehicle and with external infrastructure (V2X communication), aligns with the current trend of connectivity in automotive technology. Providing a state-of-the-art review of attacks and suggesting countermeasures demonstrates a proactive approach to mitigating potential risks. It's essential not only to identify vulnerabilities but also to propose effective solutions to safeguard vehicular communications and, ultimately, the control layer responsible for critical vehicle functions. [ABSTRACT FROM AUTHOR]

Copyright of Ingenius, Revista Ciencia y Tecnología is the property of Universidad Politecnica Salesiana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: The proposed antenna is a small wideband monopole with wideband circular polarization using heterogeneous bidirectional recurrent neural network for both narrow and wide band applications (NWB‐MAD‐HBRNN). The electromagnetic structure is designed, fabricated, and simulated with 1 mm thickness on FR4 substrate material along dielectric constant 4.3. The proposed antenna includes 4.3–8.85 GHz for ultrawideband applications; it contains reconfigurable narrow band for L‐band 1.27 GHz, LTE, and ultrawideband applications. To enhance the antenna impedance bandwidth (BW) along axial ratio bandwidth (ARBW), a slit is etched at the antenna patch, a rectangular stub is inserted into the ground plane, and semicircular stub is added to the top of antenna feed line. The better agreement is observed in the measured and simulated gain performance of 4.8 dB for LTE band applications. The proposed NWB‐MAD‐HBRNN design provides 13.50%, 18.91%, and 22.58% higher bandwidth and 18.36%, 20.38%, and 27.58% lower return loss than the existing designs, such as bio‐inspired wideband antenna for wireless applications based on perturbation technique (BWA‐WA‐PA), a compact circularly polarized modified printed monopole antenna for wireless applications (CCP‐MPMA‐WA), and new multiband monopole antenna for certain broadband wireless applications along wireless personal communications (PA‐MMA‐BWA), respectively. [ABSTRACT FROM AUTHOR]

The rapid advancement of communication technologies underscores the urgent need for robust and adaptable emergency communication systems (ECSs), particularly crucial during crises and natural disasters. Although network-based ECSs have been extensively studied, integrating open-source technologies, such as software-defined wide area networks (SD-WAN) with private long-term evolution (LTE) base stations, is a relatively unexplored domain. This study endeavors to fill this gap by introducing an experimental ECS platform that utilizes a hybrid network, incorporating a VoIP network to enhance open-source and on-premises communications in targeted areas. Our hypothesis posits that a hybrid network architecture, combining SD-WAN and private LTE, can substantially improve the reliability and efficiency of ECSs. Our findings, supported by the open-source OMNeT++ simulator, illuminate the enhanced communication reliability of the network. Moreover, the proposed platform, characterized by autonomous wireless 4G/LTE base stations and an Asterisk VoIP server, demonstrates improved quality of service (QoS) and quality of experience (QoE), with minimal data loss. This research not only has immediate practical applications but also bears significant implications for the development of cost-effective, open-source communication networks, optimized for emergencies, critical infrastructure, and remote areas. [ABSTRACT FROM AUTHOR]

The present article discusses three different frameworks of Reflective Practice (RP) intended to foster reflection in the fields of English Language Teaching (ELT) and Language Teacher Education (LTE). Therefore, we look at structural platforms of procedures or ways of engaging in reflection and/or analysing its outcomes. The following are the frameworks, discussed in terms of their contribution for the refinement of both individual and collaborative professional development: Zwozdiak-Myers’s framework of reflective practice, Farrell’s Framework for reflecting on practice and Edge’s framework of cooperative development. We look into the term critical in the field of LTE and discuss the frameworks after a brief overview of the complexities involved in reflection, ranging from daily classroom procedures, to hegemonic assumptions and personal philosophical stances, including assumptions and beliefs. In a very generalised way, it can be said that the first two frameworks are designed to guide and structure evidence of reflection in self-study, whereas the third one takes a more collaborative approach, although the three frameworks can be complementary and may have practical overlaps of application. LTE. Reflective Practice. Frameworks.

The rapid advancement of communication technologies underscores the urgent need for robust and adaptable emergency communication systems (ECSs), particularly crucial during crises and natural disasters. Although network-based ECSs have been extensively studied, integrating open-source technologies, such as software-defined wide area networks (SD-WAN) with private long-term evolution (LTE) base stations, is a relatively unexplored domain. This study endeavors to fill this gap by introducing an experimental ECS platform that utilizes a hybrid network, incorporating a VoIP network to enhance open-source and on-premises communications in targeted areas. Our hypothesis posits that a hybrid network architecture, combining SD-WAN and private LTE, can substantially improve the reliability and efficiency of ECSs. Our findings, supported by the open-source OMNeT++ simulator, illuminate the enhanced communication reliability of the network. Moreover, the proposed platform, characterized by autonomous wireless 4G/LTE base stations and an Asterisk VoIP server, demonstrates improved quality of service (QoS) and quality of experience (QoE), with minimal data loss. This research not only has immediate practical applications but also bears significant implications for the development of cost-effective, open-source communication networks, optimized for emergencies, critical infrastructure, and remote areas.

These days, 5G mobile technology highly influences the wireless communication process, which is more responsive than the other generation. However, the 5G communication process handles the speed and latency issues while transmitting data over the network. Especially in rural areas, most people face this speed and latency problem while connecting to the network. Therefore, the network uses massive amounts of data to analyse this problem by integrating 5G with the Internet of things (IoT). The IoT-based data transmission and collection helps manage the data capacity, connection, and transmission rate. Therefore, this study uses the novel secured narrowband IoT framework for 5G communication and operational goals based on their position in the market. The 5G network uses business connectivity and access information to manage the data transmission. The network uses cellular bandwidth and IoT devices to connect more during this process. According to the connection, the information is transmitted with the minimum delay. Thus, experimental results have proposed these parameters: an accuracy ratio of 92.5%, a security ratio of 94.4%, a reliability ratio of 93.5%, a latency ratio of 91.8%, a cost-effective ratio of 20.5%, and a throughput ratio of 25.4% compared to other methods.

In the context of Heterogeneous Wireless Networks (HWN), achieving the best connectivity is crucial for users. With the availability of multiple Radio Access Technologies (RATs), users are constantly looking to be "Always Best Connected" (ABC) by connecting to the best possible RAT. This challenge is also important in Next‐Generation Networks (NGN), where researchers are proposing models and algorithms to make the ABC paradigm a reality. One such challenge is the network selection problem, which involves the automatic and transparent selection of the best RAT at a given time. Many papers in this field have used Multi‐Attribute Decision‐Making (MADM) methods, which have been implemented with various objectives such as increasing quality of service (QoS), reducing energy consumption and costs etc. This paper proposes a modified machine learning algorithm, specifically an adapted K‐means algorithm, to address this challenge. The results show that this proposal outperforms legacy MADM methods in terms of latency, jitter, packet loss, and data rate. So, the paper presents a new approach to network selection in HWN and NGN, and the results suggest that it could be a promising solution to this important challenge. [ABSTRACT FROM AUTHOR]

Featured Application: This novel approach provides a seamless, straightforward means to make 6LoWPAN devices—pragmatically any kind of incumbent from IPv6-based IoT networks—more accessible under the scope of the omnipresent, classic IPv4 Internet. The burgeoning complexity and heterogeneity of IoT networks, coupled with their rapid growth, constant evolution, and new players, present significant challenges in terms of connectivity, interoperability, management, and usability. These networks, composed of a diverse array of devices, technologies and the like, demand innovative solutions to bridge the gaps between different IoT technologies and communication protocols. This article presents a simple, yet efficacious communication Relay to address one of these critical gaps. This Relay uses NB-IoT to ease the integration of 6LoWPAN-based IoT devices (IPv6) into the public legacy Internet (IPv4). This device translates 6LoWPAN, IPv6 CoAP messages into Internet-standard REST requests, so that appropriate handling of devices' data be achieved in several stages. Thus, the Relay establishes two branches of communications: (i) the local network where the 6LoWPAN gateway is placed, and (ii) the public NB-IoT network. User interaction and data analysis are achieved by virtue of Home Assistant, where former 6LoWPAN devices are now discovered and shown as proper Home Assistant entities thanks to the Relay's ease of integration into the open-source platform. This novel approach not only ensures efficient data and network management, but it also meets the urgent necessity for advanced solutions in enhancing actual IoT interconnectivity and monitoring. The unprecedented pace at which IoT devices, players and different networks have been proliferating in recent times is not compatible with countless manufacturer-dependent platforms, applications, and proprietary protocols that the IoT field has been leading with so far, almost from its beginnings. [ABSTRACT FROM AUTHOR]

Energy efficiency (EE) of wireless telecommunications has become a new challenge for the research community, governments and industries in order to reduce CO2 emission and operational costs. EE of base stations (BSs) in cellular networks is a growing concern for cellular operators to not only maintain profitability, but also to reduce the overall negative impact to the environment and economic issues for wireless network operators. In this paper, a framework focuses on the Area Energy Efficiency (AEE) evaluation of LTE BSs is presented. The parameters affect on the AEE and the coverage area of LTE BS in different scenarios are investigated. AEE analysis has been done using a few key performance indicators including transmit power, bandwidth, load factor with the assumption of different scenarios (urban, suburban and rural). The simulation results show that the LTE BSs have better AEE in an urban environment for cell radius less than 750 m compare with the suburban and rural environments. Furthermore, it is obvious that there is a strong influence of traffic load, BW and transmission power on AEE of LTE network. On the other hand, AEE increases significantly as the BW size increases. Finally, it has been shown that the AEE of LTE macro BS decreases with increasing the percentage of traffic load for all scenarios. [ABSTRACT FROM AUTHOR]

Research on energy consumption and bandwidth allocation is the basis for achieving the standard of service and fairness requirements for various traffic classes within the integrated optical-wireless access networks. The energy consumption issue is increasingly vital nowadays. The access segment of both optical and wireless networks is well-known for its domination over total network power consumption. In this research paper, the full power consumption and energy efficiency of integrated Ethernet Passive Optical Network (EPON) and two wireless technologies, namely Worldwide Interoperability for Microwave Access (WiMAX) and Long-Term Evolution (LTE) with a unique EPON-based semi-dynamic bandwidth allocation (SD-DBA), are evaluated. A semi-analytical power consumption model is proposed and applied within the simulation process for energy performance evaluation. Furthermore, various issues that will affect the energy performance like split ratio, Femtocell Base Station (FBS) range, analysis of broadcast elements, and modulation schemes are considered. The obtained results prove that the EPON-WiMAX with SD-DBA has better energy efficiency compared to EPON-LTE with SD-DBA that offers the best data rates with an increase of 12% in splitting ratio, 3.846% in FBS range and 8.6957% in broadcast factor. [ABSTRACT FROM AUTHOR]

Spectrum sharing provides a rapid migration pathway toward 5G by enabling the coexistence of 4G LTE and 5G new radio (NR) that share the same spectrum. Due to significant differences in the LTE and 5G-NR air interfaces, several enablers are required to facilitate the spectrum sharing. In this study, we explore the coexistence features and investigate their impacts on network performance. For static and dynamic spectrum sharing scenarios, we assess the impacts of different spectrum sharing ratios, user ratios, MIMO configurations, mixed numerology profiles and traffic patterns on the user throughput and network capacities of spectrum sharing networks, compared with the LTE only and 5G-NR only networks with exclusive spectrum access. The key results show that spectrum sharing leads to a marginal capacity gain over LTE only network and achieves considerably lower capacity than the 5G-NR only network. Also, the results show that mixed numerology profiles between the LTE and 5G-NR lead to capacity losses due to inter-numerology interference. In addition, user and spectrum sharing ratios between LTE and 5G-NR have critical impacts on performance. Reduced spectrum per device as the number of 5G devices increases, higher signaling overhead and higher scheduling complexity are other limiting factors for spectrum sharing networks. The results show limited capacity benefits and reinforce spectrum sharing between LTE and 5G-NR as mainly an evolutionary path to accommodate 5G users in the same LTE spectrum while migrating to the fully-fledged 5G networks. For significant capacity increase, other features such as carrier aggregation, overlay of small cells and higher order MIMO would need to be incorporated into the network. [ABSTRACT FROM AUTHOR]

In this article, the design and analysis of a compact octa‐band antenna employing the PIN diode to realize frequency reconfigurable characteristics is presented. The presented antenna is backed by a partial ground plane and printed on top of a 1.53 mm thicker FR4 substrate. The antenna size is very compact (25 mm × 14 mm × 1.53 mm), and can be readily incorporated with many other RF front‐end circuits. The presented antenna consists of a semi‐heptagonal, semi‐hexagonal, inverted L‐shaped, and inverted Z‐shaped monopoles. Depending on the position of the lumped element switch, the presented antenna can operate in eight different frequency modes. The investigated antenna realizes Penta/Triple band characteristics by turning ON/OFF the PIN diode positioned between the inverted L‐shaped monopole and feedline. While in ON state, the investigated antenna covers five unique frequencies 1.82 GHz (DCS/5G NR n70), 2.43 GHz (Bluetooth/RFID), 3.75 GHz (LTE 42–43/5G NR n77/Wi‐MAX), 5.4 GHz (U‐NII‐2A & ‐2B), and 5.84 GHz (U‐NII‐3 & V2X) and in OFF state, the antenna covers three unique frequencies 1.95 GHz (PCS/UMTS/LTE 34–37), 2.59 GHz (LTE 2500 & WLAN 2.4 GHz), 4.71 GHz (5G NR n79 & WLAN 5GHz) for wireless applications. The investigated antenna exhibits excellent impedance bandwidths of 1.69–1.9 GHz (BW = 11.6%), 1.8–2.1 GHz (BW = 15.4%), 2.37–2.56 GHz (BW = 7.7%), 2.4–2.7 GHz (BW = 11.8%), 3.49–4.2 GHz (BW = 18.4%), 4.3–5.55 GHz (BW = 25.4%), 5.2–5.52 GHz (BW = 6%), and 5.78–5.9 GHz (BW = 5.5%) at 1.82/1.95/2.43/2.59/3.75/4.71/5.4, and 5.84 GHz, respectively. The measurements demonstrate that the designed antenna has omnidirectional radiation characteristics with 1.15–4.4 dBi gain. The proposed design's simulated and measured results are compared, and show good agreement. [ABSTRACT FROM AUTHOR]

Cost efficiency is an essential metric in the design of major part of what is expected to be the 5G network. Some of the 5G solutions, mainly those involving mmWave technology and network densification, are extremely expensive. Much of what was said about 5G rollout strategies has been said with regard to the world's major leaders in 5G technology and telecom infrastructure investment. However, a much more numerous group of countries often referred as emerging markets or middle-income economies has never hold a leadership in the development of cellular technologies. To date, few of them have fully leveraged the potential of 4G systems while many still have not ensured a return on investment in 3G. This gave rise to the views that these countries are not ready for 5G challenges. However, all of them are doomed to enter the era of another industrial revolution, where exactly 5G is to become the main driver. Yet, the use cases and the portfolio of services of the future networks will apparently depend on economic realities of the country where it will be deployed. There is a rather vague picture at the moment of how the 5G rollout may take place in this part of the world and that is the main reason for this study. In this paper, we outline the technical challenges and economic tensions associated with the developing of 5G physical infrastructure and address spectrum allocation issues with a particular focus on the needs of the future enhanced mobile broadband component. Then we discuss the role of government in establishing favorable regulatory framework, providing supportive policies and finding local drivers to facilitate 5G rollout and the challenges, confronting the operators paving their way to 5G. [ABSTRACT FROM AUTHOR]

5G networks, pivotal for our digital mobile societies, are transitioning from 4G to 5G Stand-Alone (SA) networks. However, during this transition, 5G Non-Stand-Alone (NSA) networks are widely used. This paper examines potential security vulnerabilities in 5G NSA networks. Through an extensive literature review, we identify known 4G attacks that can theoretically be applied to 5G NSA. We organize these attacks into a structured taxonomy. Our findings reveal that 5G NSA networks may offer a false sense of security, as most security and privacy improvements are concentrated in 5G SA networks. To underscore this concern, we implement three attacks with severe consequences and successfully validate them on various commercially available smartphones. Notably, one of these attacks, the IMSI Leak, consistently exposes user information with no apparent security mitigation in 5G NSA networks. This highlights the ease of tracking individuals on current 5G networks. [ABSTRACT FROM AUTHOR]

As a part of the post-publication peer review, readers can send comment letters to a journal on the articles it has published. Such letters critically comment on the content of the related article. They allow the readers to see the messages of the article in the context of the criticisms, give the authors of the concerned article an opportunity to clarify their stand, help initiate scientific dialogues, and, with consequent corrections or retractions, even help perfect the scientific literature. Comment letters should be relevant, scientifically foolproof, short, focused, straightforward, balanced, and polite.

Recent advancements in communication technologies have significantly enhanced localization techniques, improving both accuracy and operating modes. Initially, localization methods relied on global navigation satellite systems, offering high accuracy but proving inefficient in Non-Line-of-Sight scenarios. Furthermore, the absence of a passive mode, where the user can be localized without explicitly requesting it, renders these methods unsuitable for applications like passive tracking systems. Fingerprinting methods, a pattern matching techniques based on signal power estimation from target devices and distance estimation from reference points, can be seen as a valid and promising alternative. However, these methods face limitations due to extensive measurement campaigns needed to establish accurate sampling systems within specific areas and the substantial amount of data required for machine learning algorithms to achieve optimal performance. This study introduces a novel fingerprinting method capable of passive operation, involving all smartphones within a designated area, suitable for both indoor and outdoor scenarios. The proposed solution leverages Generative Adversarial Networks (GANs) to augment fingerprinting datasets, enhancing machine learning models’ capabilities. Additionally, the offline phase’s cost-effectiveness is improved by integrating a Bayesian system as a secondary machine learning component.

Ambient backscatter communication (ABC) is considered as a promising paradigm for meeting the 6G massive Internet of Things (IoT) requirements which is expected to revolutionize our world. In this paper, a new multimode matching game and machine learning-based IoT ambient backscatter communication scheme is proposed to maximize the ABC system rate and capacity over the LTE and Wi-Fi multi-RAT heterogeneous network, thereby supporting the 6G green massive IoT communication. The proposed algorithm is designed to support different rate and capacity requirements for different massive Machine Type Communication (mMTC) use cases such as sensor networks, smart grid, agriculture and low data rate Ultra Reliable Low Latency Communication (URLLC) use cases such as tactile interaction. The proposed optimization algorithm runs into two phases, the first one is a matching game-based algorithm that selects the optimum association between the IoT tags and the primary users (PU) downlink signals from a specific base station which maximizes the IoT tags rate while minimizing the resulting interference to the PU. Each IoT tag can ride the PU downlink signal using one of three different riding modes according to the required IoT ABC system rate and capacity, whereas mode 1 allows multiple IoT tags to ride the whole PU downlink signal resource blocks, in mode 2 each IoT tag can ride only one subcarrier from the PU downlink signal resource blocks, while in mode 3 multiple IoT tags can ride the same subcarrier from the PU downlink signal resource blocks. In addition, unmanned aerial vehicles (UAVs) flying HetNodes equipped with LTE and Wi-Fi receivers are used as backscatter receivers to receive the IoT tags uplink backscattered signals, so the second optimization phase is formulated to maximize the total sum rate of the ABC system by dividing its service area into clusters using the enhanced unsupervised k-means algorithm, also the enhanced k-means algorithm finds the optimum location of each cluster’s serving UAV flying HetNode that maximizes the channels gain between the IoT tags and the serving UAV flying HetNode in order to maximize the total system rate. The system model was implemented within the MATLAB environment where simulations across the various scenarios are conducted to assess the effectiveness of the proposed algorithm. Simulation results and the performance analysis demonstrated that the proposed algorithm can support the required rate for the most mMTC and low data rate URLLC IoT applications with average IoT tag rates in the range of 15 Kbps to 115 Kbps, and outperforms the algorithm-free riding technique in the case of massive IoT applications. The proposed mode 2 (first enhanced mode) achieves the best performance in terms of the average IoT tags rate and the total system rate with the lowest interference to the primary system users, on the other hand, mode 3 (second enhanced mode) improves the system capacity with maximum IoT tags satisfaction ratio. The capacity and satisfaction ratio of the proposed mode 3 outperforms mode 1 by 300 % and 138% respectively and outperforms mode 2 by 2,000 % and 420 % respectively. The proposed algorithm reduces the interference power to the PUs on the average by $1:\left(15.69 \times 10^{-12}\right)$ relative to the algorithm-free riding technique. From the result, we can conclude that the proposed algorithm supports different IoT applications and achieves the required data rates with minimal effect on the primary system keeping the PU’s data rate within the required range compared to the algorithm-free riding technique with the cost of higher time complexity.

Cellular Vehicle-to-Everything (C-V2X) has become one of the most anticipated technologies for vehicular safety network. In LTE C-V2X Basic Safety Messages (BSMs) are transmitted on radio resources that are allocated with a periodic resource reusability. This allocation is based on a semi persistent sensing-based scheduling scheme (SPS) algorithm. But, due to this reuse of periodic resources, the possibility of loss of consecutive packets between the same vehicle pair is significant. This study discusses different approaches proposed to solve this consecutive loss problem. Based on this investigation, this article suggests an efficient One-Shot based solution with a new control parameter, that performs superior to the state-of-the-art solution that is standardized in SAE J3161/1 which this article analyzes and shows to have limitation in case of high-density scenario.

5G networks, pivotal for our digital mobile societies, are transitioning from 4G to 5G Stand-Alone (SA) networks. However, during this transition, 5G Non-Stand-Alone (NSA) networks are widely used. This paper examines potential security vulnerabilities in 5G NSA networks. Through an extensive literature review, we identify known 4G attacks that can theoretically be applied to 5G NSA. We organize these attacks into a structured taxonomy. Our findings reveal that 5G NSA networks may offer a false sense of security, as most security and privacy improvements are concentrated in 5G SA networks. To underscore this concern, we implement three attacks with severe consequences and successfully validate them on various commercially available smartphones. Notably, one of these attacks, the IMSI Leak, consistently exposes user information with no apparent security mitigation in 5G NSA networks. This highlights the ease of tracking individuals on current 5G networks.

In the early phase, the number of new radio (NR) users is considerably low compared to the long-term evolution (LTE) users. Hence, allocating the LTE spectrum to a small number of NR users will have a detrimental effect on the LTE users. To overcome this backdrop, dynamic spectrum sharing (DSS) between LTE and NR has become an emerging technology where both systems can coexist on the same LTE spectrum. However, the most critical factor for LTE and NR coexistence is to share the spectrum resources of LTE systems with data and control signals necessary to operate NR systems subject to not impacting LTE operations. In line with this, a comprehensive understanding of DSS for LTE and NR coexistence taking into account diversified concerns is presented in this paper. First, an overview of the technological background of essential signals and channels of both LTE and NR systems to enable DSS for their coexistence is given. Numerous deployment options and potential design considerations of DSS are then discussed. The application of DSS to both multicast-broadcast single-frequency network (MBSFN) and non-MBSFN LTE subframes under NR with and without synchronization signal/ physical broadcast channels (PBCH) block (SSB) transmissions is examined. Further, the third-generation partnership project (3GPP) standardization activities towards DSS in its different releases are discussed, numerous use cases are highlighted, and the significance and limitations of DSS are identified. To provide additional insights, the relative comparison of potential aspects of several DSS concerns including, deployment options, design considerations, DSS applications, and 3GPP standardization efforts, is carried out. Finally, a summary of key lessons learned is provided in terms of numerous facts and figures.

In this paper, the prototypical deployment of a Multiple-Input-Multiple-Output (MIMO) antennas system, denoted as Smart Selective Antennas System (SSAS), aiming at mitigating inter-cell interference effects of cellular networks for in-flight Unmanned Aerial Vehicles (UAVs), is discussed. In detail, the proposed SSAS is beneficial to increase the communication reliability over existing cellular networks, especially with regard to complex Beyond Visual Line of Sight (BVLOS) drones’ missions and applications. Its deployment is motivated as existing 4G Long Term Evolution (LTE) cellular networks (as well as 5G networks) are mainly designed and optimized for terrestrial utilization, thus not taking into account interference effects on flying connected devices. The prototypical implementation of the SSAS has been expedient to conduct multiple experimental flights with a drone at different altitudes, collecting performance results and validating the proposed SSAS as a viable solution for inter-cell interference mitigation.

The evolution of Critical Communications has been conditioned by the underlying networks ranging from previous narrowband almost voice-only Private Mobile Radios (PMR) to now multimedia capable broadband Long Term Evolution (LTE) / fifth generation (5G). Due to the nature of critical communications, the 3rd Generation Partnership Project (3GPP) has defined a series of requirements and recommendations to ensure that availability and performance of Mission Critical Services (MCX) are guaranteed specially in massive group communications. However, no study has been conducted to determine if required capacity and scalability conditions in crisis events can be actually satisfied by commercial or even hybrid LTE/5G networks. This paper presents an analysis of the capacity limitations of the MCX voice service over broadband networks in terms of number of concurrent streams that can be served per cell by comprehensively identifying the different transmission and protocols related bottlenecks. The aggregation of such constraints results in a theoretical model for the maximum capacity of LTE/5G, far more realistic than coarse grain estimations that consider overall cell peak rate. Furthermore, a comparison between MCX over LTE and 5G is provided, indicating the ratio of unusable or wasted radio resources to the total amount available. This way not only actual maximum achievable capacity but also a measure of the efficiency in terms of radio resource usage is provided, which is extremely important for the business model behind hybrid deployments. Both results will contribute towards better network dimensioning as well as possible finer tuning of network and service parameters.

Abstract Objective Lonicera japonica Thunb (LJT) is a commonly used herbal soup to treat inflammation-related diseases. However, the effect of LJT on ALI is unknown. The present study was aimed at investigating the protective effects of LJT extract (LTE) and its active ingredient luteolin (Lut) on lipopolysaccharide (LPS)-stimulated ALI and investigate its potential mechanism. Materials and methods The effects of LTE and Lut were explored in an ALI mouse model induced by intraperitoneal injection of lipopolysaccharide (LPS). Besides, the LPS-induced inflammation model in BEAS-2B cells was used to clarify the underlying mechanisms. The ALI pathological changes in lung tissues were tested through Haematoxylin and eosin (HE) staining. The apoptosis of cells in lung tissue and the cell model in vitro was evaluated by TUNEL assays, respectively. Meanwhile, the viability of cells in vitro was evaluated by Cell Counting Kit-8 (CCK-8) assay. The levels/concentrations of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-1β and IL-10 in BALF were detected by enzyme-linked immunosorbent assay (ELISA). Besides, through quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting, the expression of the above-mentioned inflammatory factors and key factors in the NF-κB signaling pathway was examined. The distribution of inflammatory factors in tissue was observed through immunohistochemistry (IHC) assays . Results In relative to LPS-stimulated group, the in vivo study showed that LTE and different concentrations of Lut dramatically alleviated LPS-evoked lung pathological injury and lung edema based on the changes in total protein levels and lung wet/dry (W/D) ratio in the bronchoalveolar lavage fluid (BALF) from ALI mice. LTE and different concentrations of Lut also suppressed the inflammatory response, as reflected by the variations of neutrophil accumulation and the production of proinflammatory and anti-inflammatory cytokines in the lung tissues and BALF of ALI mice. The in vitro research also demonstrated that LTE and Lut visibly facilitated cell viability and restrained the apoptosis of BEAS-2B cells stimulated by LPS. Lut hindered LPS-inducible activation of NF-κB pathway in BEAS-2B cells. Conclusion The present study proved that LTE might suppress LPS-induced acute injury and inflammation in mice and BEAS-2B cells through the Lut-caused suppression of NF-κB signal path (Figure 1).

This paper analyzes the quantitative quality parameters of a mobile communication network in a controlled drone logistic use-case scenario. Based on the analysis of standards and recommendations, the values of key performance indicators (KPIs) are set. As the main network-impacting parameters, reference signal received power (RSRP), reference signal received quality (RSRQ), and signal to interference and noise ratio (SINR) were selected. Uplink (UL), downlink (DL), and ping parameters were chosen as the secondary ones, as they indicate the quality of the link depending on primary parameters. The analysis is based on experimental measurements performed using a Latvian mobile operator’s “LMT” JSC infrastructure in a real-life scenario. To evaluate the altitude impact on the selected network parameters, the measurements were performed using a drone as transport for the following altitude values: 40, 60, 90, and 110 m. Network parameter measurements were implemented in automatic mode, allowing switching between LTE4–LTE2 standards, providing the opportunity for more complex analysis. Based on the analysis made, the recommendations for the future mobile networks employed in controlled drone flights should correspond to the following KPI and their values: −100 dBm for RSRP, −16 dB for RSRQ, −5 dB for SINR, 4096 kbps for downlink, 4096 kbps for uplink, and 50 ms for ping. Lastly, recommendations for a network coverage digital twin (DT) model with integrated KPIs are also provided.

This paper delves into an interference analysis, focusing on the forthcoming Starlink Generation 2 satellites, stated to operate within the 1990–1995 MHz frequency band. The aim is to assess the potential interference from this Starlink system to the satellite receivers of mobile satellite systems (MSSs), which are set to function within the 1980–2010 MHz range, and satellite receivers of the NTN systems, which are planned to operate in the n256 bands, defined by the 3GPP specifications. Through simulation-based evaluations, both single-entry and aggregate interference levels from Starlink to MSSs and NTN systems are comprehensively explored. To estimate the interference impact, several protection criteria were used. The study is in line with the Recommendations of International Telecommunication Union (ITU-R) and common approaches that are used when performing compatibility studies between satellite systems. The findings of this study demonstrate the feasibility of utilizing the n25 band for NTN direct-to-device services. [ABSTRACT FROM AUTHOR]

Cellular coverage plays an important role in throughput enhancement. So as to increase coverage especially in the dead spots of corporate buildings and shopping malls; 'G' number of micro cells (or Femtocells) are installed. These micro cells operate on both the licensed LTE spectrum and WiFi's unlicensed spectrum in LTE-U mode. In this mode, out of 40 mSec time, WiFi Access Point utilizes the channels of unlicensed spectrum for some amount of time and for the remaining time (= T); 'G' micro cells adopt these channels. For all the channels used by micro cells, powers are assigned that endeavour to optimize the total throughput of 'G' micro cells. Further, because of allotted powers, sustainable interference only is to be created to the data sent from macro cell and other micro cells. Moreover, all the users of micro cells have to get enough signal strength from their corresponding micro cells. Besides, the throughput of the micro cells needs to exceed the desired limit. Hence, the foregoing resource allocation is tagged with 'Resource Allocation in FemTocells' (RAFT). Here, average powers are measured with closed-form solution and using these average powers, optimal solution is produced for the RAFT with computational overhead that is considerably lower than that of the prevailing 'conventional iterative algorithms' by a factor of O(10 5 ). [ABSTRACT FROM AUTHOR]

Mid-term (MTEs, 5-20 years) and long-term (LTEs, 20+ years) field experiments are key sources of information to design future climate-smart agriculture. Within the European Joint Program SOIL (EJP SOIL), we built the EJP SOIL-MTE/LTE metadataset that contains metadata from 240 MTEs/LTEs across Europe. Metadata collected included precise descriptions of the treatments (combination of factors such as tillage, crop type/rotation, amendments/fertilizers, grazing and pest/weed management), soil and crop measurements and pedo-climatic information. Using different figures and dashboards, an overview of those MTEs/LTEs is presented and specific research themes (tillage systems, residue management, amendment type and cover crops) are further analysed within their pedo-climatic context. An interactive web portal developed in collaboration with the BonaRes project (https://lte.bonares.de), enables users to explore the metadataset and find relevant MTEs/LTEs for specific combinations of practices (e.g. all MTEs/LTEs that investigate cover crops on a Cambisol in no-tillage system). Finally, a SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis of the metadataset was carried out to highlight the potential contribution of MTEs/LTEs to a harmonized European soil observation and monitoring approach. We propose that the metadataset could be elaborated with metadata from other existing MTEs/LTEs in Europe or even worldwide. [ABSTRACT FROM AUTHOR]

In this work the discrete cosine transform is proposed for LTE systems with the aid of feed-forward neural network as a suitable equalizer to retrieve the effect of channel within Rayleigh Faded channels. This system was implemented using the QuadraturePhase Shift Keying as a modulation technique, and using different Maximum Doppler Shift, which represents the highest Doppler shift that can occur between the transmitter and the receiver in a given wireless channel. by using DCT-FFNN with different MDS values effectively mitigates signal distortion resulting from multipath propagation and common issues in wireless communication networks and demonstrates higher accuracy in predicting BER values. According to the research, the performance will be better at MDS 50 when compared to the rest of the MDS used in the paper. These advantages come with minimal loss in data rate and bandwidth and no additional expense in terms of power. The simulation results indicate that an FFNNs-based channel estimator outperforms the pilot-based channel estimator in LTE systems operating over a Rayleigh fading channel, because FFNNs have low complexity and can quickly and accurately adjust the signal strength of incoming signals based on their input. All LTE system models were implemented using MATLAB 2016. [ABSTRACT FROM AUTHOR]

Complex physical phenomena take place while dealing with the convective heat transfer in porous medium. Due to involved complexities, most of the earlier numerical studies are performed using various porous models compromising the detailed phenomena. Therefore, a pore-scale simulation has been performed for convective heat transfer in triply-periodic-minimal-surface lattices, with identical void fraction and unit-cell size, but different geometrical shapes (tortuosity), namely Diamond, Inverted Weaire–Phelan, Primitive, and Gyroid. Further, each lattice derived into three different types of porous structures by designing second subdomain as solid (in Type 1), fluid (in Type 2), and microporous zones (in Type 3). The convective heat transfer in a square mini-channel filled with the porous structures is investigated for the range of flow Reynolds number 0.01 < Re < 100 and Pr = 7 . The temperature distributions, solid and fluid Nusselt numbers on the external walls and on the internal walls, and quantitative departure from local thermal equilibrium (LTE) assumption are calculated for different porous media. The effect of porous morphology/tortuosity and effective porosity on the heat transfer is examined. The results revealed that the maximum temperature within the domain is found in Type 2 treatment, leading to inferior heat transfer performance compared to Type 1 and Type 3. Among all the lattices, the Diamond lattice provides more uniform temperature distribution over the external walls and within the volume including solid and fluid. The effective and the internal Nusselt numbers increase drastically for Re > 10. For the range of Re considered here, the Primitive lattice shows the maximum deviation from LTE assumption. [ABSTRACT FROM AUTHOR]

Objective: Lonicera japonica Thunb (LJT) is a commonly used herbal soup to treat inflammation-related diseases. However, the effect of LJT on ALI is unknown. The present study was aimed at investigating the protective effects of LJT extract (LTE) and its active ingredient luteolin (Lut) on lipopolysaccharide (LPS)-stimulated ALI and investigate its potential mechanism. Materials and methods: The effects of LTE and Lut were explored in an ALI mouse model induced by intraperitoneal injection of lipopolysaccharide (LPS). Besides, the LPS-induced inflammation model in BEAS-2B cells was used to clarify the underlying mechanisms. The ALI pathological changes in lung tissues were tested through Haematoxylin and eosin (HE) staining. The apoptosis of cells in lung tissue and the cell model in vitro was evaluated by TUNEL assays, respectively. Meanwhile, the viability of cells in vitro was evaluated by Cell Counting Kit-8 (CCK-8) assay. The levels/concentrations of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-1β and IL-10 in BALF were detected by enzyme-linked immunosorbent assay (ELISA). Besides, through quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting, the expression of the above-mentioned inflammatory factors and key factors in the NF-κB signaling pathway was examined. The distribution of inflammatory factors in tissue was observed through immunohistochemistry (IHC) assays. Results: In relative to LPS-stimulated group, the in vivo study showed that LTE and different concentrations of Lut dramatically alleviated LPS-evoked lung pathological injury and lung edema based on the changes in total protein levels and lung wet/dry (W/D) ratio in the bronchoalveolar lavage fluid (BALF) from ALI mice. LTE and different concentrations of Lut also suppressed the inflammatory response, as reflected by the variations of neutrophil accumulation and the production of proinflammatory and anti-inflammatory cytokines in the lung tissues and BALF of ALI mice. The in vitro research also demonstrated that LTE and Lut visibly facilitated cell viability and restrained the apoptosis of BEAS-2B cells stimulated by LPS. Lut hindered LPS-inducible activation of NF-κB pathway in BEAS-2B cells. Conclusion: The present study proved that LTE might suppress LPS-induced acute injury and inflammation in mice and BEAS-2B cells through the Lut-caused suppression of NF-κB signal path (Figure 1). [ABSTRACT FROM AUTHOR]

When designing a narrow band Internet of things (NB-IoT) system, the main tasks are to determine the boundary parameters of the system nodes and check its performance under various conditions. Automatic design tools make it possible to achieve reliable results even at the modeling stage, which helps to accelerate the development and implementation of new technologies in the microelectronic industry, including the industrial Internet of things. This paper presents aspects of designing an NB-IoT system. Analytical calculations of the receiving path are carried out using a debugging system in the context of radio wave propagation in an enclosed space in accordance with the specifications of the 5G 3GPP standard. Based on the results of analytical calculations on signal propagation in a closed space for a prototype of a subscriber device, general requirements for the development of an active node of a low-noise amplifier (LNA) of the receiving path of an NB-IoT transceiver are formulated. Based on the requirements and design standards of the 180-nm CMOS process, a prototype of an LNA is developed for operation as part of an NB-IoT transceiver of a subscriber terminal. The prototype low noise amplifier is designed in three stages and has a noise figure of 1.7 dB in the n7 frequency range with a gain of 25 dB. Digital CMOS libraries are adapted to unify and reduce the cost of the development process of analog nodes of the transceiver path, in this case an LNA. [ABSTRACT FROM AUTHOR]

This paper introduces log periodic dipole antenna based quasi-Yagi antennas that are well-suited for advanced multi-band wireless applications. The examined antennas in this study are fed by means of a coaxial feed. Impedance matching was achieved through utilization of an impedance transformer (balance to unbalance). The antennas discussed herein, labeled as antennas 1 and 2, provide a total of four and five operational bands, respectively. The first antenna exhibits resonance frequencies at 2.11 GHz, 5.4 GHz, 6.55 GHz, and 8.55 GHz. The related values for gain, bandwidth, and FBR (front-to-back ratio) at these resonances are (5 dB, 3.7 dB, 2.6 dB, and 3.3 dB), (42.6%, 14.8%, 7.63%, and 22.22%) and (10 dB, 5.5 dB, 7 dB, and 5.5 dB), respectively. Similarly, the second antenna showcases resonant frequencies positioned at 1.795 GHz, 2.54 GHz, 3.835 GHz, 5.1 GHz, and 7.11 GHz. At these resonances, gain, bandwidth, and FBR (front-to-back ratio) are (5.61 dB, 4.91 dB, 4.48 dB, 3.25 dB, and 2.44 dB), (8.35%, 36.2%, 2.0%, 20.2%, and 7.59%), and (20.30 dB, 13.83 dB, 10.22 dB, 14.59 dB, and 14 dB), respectively. Given these values, the aforementioned antennas prove to be beneficial for WLAN, and 6 GHz (5.925–7.125 GHz) Wi-Fi applications, and 4G-LTE bands 3, 7, 16, 46, and 84. Finally, the measured data was compared with the analytical data for validation of the proposed antennas. [ABSTRACT FROM AUTHOR]

Since the advent of cellular networks represented by the first-generation GSM to the current generations (4G, 5G) represented by the LTE network. This brought about a qualitative revolution in cellular networks in terms of quality, speed, and efficiency. The emergence of cellular networks accompanied by the need to locate the user for commercial and marketing purposes, therefore emerge need for the concept of location-based services (LBS). However, with the increased reliance on cellular networks by users, there appeared a second trend to locate the user for security purposes and emergency. This was the first system established in the United States of America, called federal communication commission (FCC) 911. Position locating has also penetrated the military, security, and police investigations fields to locate criminals. Therefore, we review the methods of determining location in LTE networks. We evaluate each method and identify its weaknesses. In addition, we determine the most appropriate method for law enforcement. Based on the evaluation that showed the most effective way to determine the location used by law enforcement authorities is the radio frequency (RF) fingerprint. Then employment of artificial intelligence (AI)/machine learning (ML) to obtain an optimal method. [ABSTRACT FROM AUTHOR]

Abstract A compact eight-element multiple-input multiple-output (MIMO) antenna array operating at the sub-6-GHz (LTE band 52) for the 5G handheld applications is proposed. The antenna array is realized by employing eight couple-fed slots etched on the ground plane of the MIMO antenna system. The size of the slot radiators excites the required operating bandwidth. A parametric analysis study of the effect of varying the size of the slot radiators on the ground plane is provided to give some insight into the operation of the proposed antenna system. The radiators are excited by 50-Ω strip lines. Rectangular-shaped slits are used as isolation structures to mitigate the mutual coupling effect between elements, resulting in a low Envelope Correlation Coefficient (ECC) of less than 0.1 at the operating bandwidth. The proposed MIMO antenna was fabricated and experimentally validated. The measured and simulated results are in good agreement. Other MIMO performance indicators, such as radiation patterns, Mean Effective Gain (MEG), and the proposed MIMO antenna system’s total efficiencies, are being analyzed. Measurements and simulation results are consistent, which shows that the proposed antenna is a good candidate for 5G applications in the LTE band 52.