Wireless Channel Research Articles

Experiences of Rural Secondary School Teachers in the Integration of Technology during Emergency Remote Teaching during the COVID-19 Pandemic in Namibia: An Exploratory Study

This study explored the experiences of rural secondary school teachers in Namibia during emergency remote teaching (ERT) owing to the COVID-19 pandemic. The TPACK framework and sociocultural theory were used. Semi-structured interviews and focus group discussions with 26 rural teachers revealed that despite the availability of technological tools such as laptops, smartphones, and radio and television channels, integrating these into the teaching process posed significant challenges. A lack of technological knowledge among teachers coupled with infrastructure issues and inadequate institutional support hampered the smooth execution of ERT. Despite these challenges, teachers employed innovative methods to engage their students remotely. However, the findings underline the need for increased digital literacy, better ICT resource allocation, and adequate teacher training to successfully navigate a technology-driven teaching environment. This study provides insights into educational practice, policy initiatives, and future research toward a resilient and technology-enhanced educational system.

Taking on Social Media as New Gatekeepers among Young People: A Call upon Digital Literacy

Today’s public sphere is increasingly shaped by a dynamic, global, cross-cutting digital landscape, mostly ruled by social media and algorithms. Individuals are the raw material, the product, in this digital scenario, insofar as they generate and create information that coexists and is consumed alongside the information generated by the media outlets. In this context, this study focusses on an international sample from three countries (Spain, Colombia, and Costa Rica) to study the youngest information consumption, the trust they relay in media used to get informed, and their perceptions. The research was articulated from a quantitative methodological approach, focusing on a descriptive and correlational perspective. The results show interesting and innovative outcomes that point out that country origin does not constitute a significative factor when describing consumption patterns related to social media. It was confirmed in the study that these scenarios seem to become the new gatekeepers for young people, who barely consume traditional media such as press or radio broadcast. The lack of trust in the media that they consume to get informed is a matter of awareness, and digital literacy is described to be the most appropriated solution in a transformative normality in which young people do not consume information from traditional media.

A new derivation of the Nakagami-m distribution as a composite of the Rayleigh distribution

Mobile communications systems are affected by what is known as fading, which is a well-known problem largely studied for decades. The direct consequence of fading is the complete loss of signal (or a large decrease of the received power). Rayleigh fading is a reasonable model for wireless channels although, Nakagami-m distribution seems better suited to fitting experimental data. In this paper we obtain the Nakagami-m distribution as a composite (mixture) of the Rayleigh distribution, a result which as far as we know it has not been shown in the literature. This representation of the Nakagami-m distribution facilitates computations of the average BER (Bit Error Rate) for DPSK (Differential Phase Shift Keying) and MSK (Minimum-Shift Keying) modulations for this distribution and higher moments of them, which is of great applicability to modeling wireless fading channels. Furthermore, a simple, not depending on any special function, apart of the Gamma function, bivariate version of the Nakagami-m distribution is also proposed as a special case of the multivariate version which is also presented. The proposed composite distribution is simulated through the standard procedure of summation of phasors, and results for the new closed-form measures for the MSK modulation are also shown. From that it is clear that the alternative formulation of the Nakagami-m distribution allows for easier modeling of fading fading-shadowing wireless channels through the new explicit second order statistics metrics. is well suited for modelling fading-shadowing wireless channels.

Communication Efficient Distributed Newton Method over Unreliable Networks

Distributed optimization in resource constrained devices demands both communication efficiency and fast convergence rates. Newton-type methods are getting preferable due to their superior convergence rates compared to the first-order methods. In this paper, we study a new problem in regard to the second-order distributed optimization over unreliable networks. The working devices are power-limited or operate in unfavorable wireless channels, experiencing packet losses during their uplink transmission to the server. Our scenario is very common in real-world and leads to instability of classical distributed optimization methods especially the second-order methods because of their sensitivity to the imprecision of local Hessian matrices. To achieve robustness to high packet loss, communication efficiency and fast convergence rates, we propose a novel distributed second-order method, called RED-New (Packet loss Resilient Distributed Approximate Newton). Each iteration of RED-New comprises two rounds of light-weight and lossy transmissions, in which the server aggregates the local information with a new developed scaling strategy. We prove the linear-quadratic convergence rate of RED-New. Experimental results demonstrate its advantage over first-order and second-order baselines, and its tolerance to packet loss rate ranging from 5% to 40%.

Shapley’s Value as a Resource Optimization Strategy for Digital Radio Transmission over IBOC FM

The hybrid in-band on-channel (IBOC) transmission system, which serves as a digital audio radio scheme, facilitates the simultaneous transmission of analog FM and digital audio. In IBOC systems, broadcasters transmit signals within allocated channel bands, posing a challenge in bandwidth allocation for digital audio transmission. To address this, cooperative game theory, supported by the bankruptcy game and Shapley’s value, is proposed as a strategy to optimize bandwidth allocation at each node or station. This approach considers service demand, the number of stations, and radio channel conditions in the FM band. The paper presents a scenario under saturated traffic conditions to evaluate the degree of optimization achievable using the Shapley value under clearly defined traffic and channel conditions. The results indicate that cooperative game theory, with the support of the Shapley value, offers an excellent alternative for optimizing bandwidth in digital broadcasting over IBOC in FM, with potential applicability in other digital radio broadcasting systems.

The Effects of Multi-Level Diversity on Team Innovation: The Role of Collaborative Capability

Objective: This study examines the effects of surface-level, deep-level, and functional-level diversity on team innovation. This study also examines the moderation effect of the collaborative capability toward diversity and team innovation. Design/methodology/approach – The sample for this research was 175 creative team members who were then integrated into 38 creative teams of radio and television broadcasting institutions. Data collection was done using a survey method. Findings – This study indicates that surface-level and deep-level diversity negatively impact team innovation, while functional-level diversity has a positive. In addition, the study found that collaborative capability has been moderated on surface-level diversity and team innovation. However, collaborative capability does not moderate the effect of deep- and functional-level diversity on the innovation team. Originality/value – This research contributes to the team innovation literature by examining the influence of three characteristics of team diversity consisting of surface level, deep level, and functional comprehensively on team innovation, as well as the moderating role of collaboration capability as a contextual factor. Practical/Policy implication: From a practical perspective, this study has important implications for how practitioners in creative teams overcome surface and deep-level diversity challenges and take advantage of the functional-level diversity of members in creative teams. This research also increases understanding of the value of diversity in the context of team innovation.

Lexical Variations in the Ewe Language Spoken In Ho in the Volta Region of Ghana

The study was conducted to investigate the lexical variances observed in the Ewe language spoken among the Ho group. This study aims to examine the observed variations in speech patterns among both indigenous individuals and immigrants residing in the vicinity of Ho, the capital city of the Volta Region. The data analysis used the application of Labov's variationist theory from 1996 and Giles' speech accommodation theory from 1973. Information was gathered from native communities and those who had migrated to the area under investigation. The research employed a qualitative methodology and utilized purposive sampling procedures. The data were acquired through the utilization of observational methods, interviews, and the analysis of live radio broadcasts. Investigations have uncovered substantial regional and social disparities in the Ewe language spoken in Ho, leading to the utilization of distinct linguistic characteristics in everyday communication. The dialects within the speech community exhibit lexical, phonological, and grammatical diversity. There are some lexicons that the three dialects share, while others are unique to only two of the three dialects. Additionally, there are certain lexicons that are different from one dialect to another. The study provides confirmation that the dialectal backgrounds of language users within the speech community do not have an impact on the issue of mutual understanding. This is evident from the fact that the Eedome, Aŋlↄ and Tↄŋu dialects can be considered as being mutually intelligible. Keywords: Lexical, variation, ewe language, Eedome and Tↄŋu or Aŋlↄ, Tↄŋu, Ho

Development of an artificial intelligence based occupational noise induced hearing loss early warning system for mine workers.

Occupational Noise Induced Hearing Loss (ONIHL) is one of the most prevalent conditions among mine workers globally. This reality is due to mine workers being exposed to noise produced by heavy machinery, rock drilling, blasting, and so on. This condition can be compounded by the fact that mine workers often work in confined workspaces for extended periods of time, where little to no attenuation of noise occurs. The objective of this research work is to present a preliminary study of the development of a hearing loss, early monitoring system for mine workers. The system consists of a smart watch and smart hearing muff equipped with sound sensors which collect noise intensity levels and the frequency of exposure. The collected information is transferred to a database where machine learning algorithms namely the logistic regression, support vector machines, decision tree and Random Forest Classifier are used to classify and cluster it into levels of priority. Feedback is then sent from the database to a mine worker smart watch based on priority level. In cases where the priority level is extreme, indicating high levels of noise, the smart watch vibrates to alert the miner. The developed system was tested in a mock mine environment consisting of a 67 metres tunnel located in the basement of a building whose roof top represents the "surface" of a mine. The mock-mine shape, size of the tunnel, steel-support infrastructure, and ventilation system are analogous to deep hard-rock mine. The wireless channel propagation of the mock-mine is statistically characterized in 2.4-2.5 GHz frequency band. Actual underground mine material was used to build the mock mine to ensure it mimics a real mine as close as possible. The system was tested by 50 participants both male and female ranging from ages of 18 to 60 years. Preliminary results of the system show decision tree had the highest accuracy compared to the other algorithms used. It has an average testing accuracy of 91.25% and average training accuracy of 99.79%. The system also showed a good response level in terms of detection of noise input levels of exposure, transmission of the information to the data base and communication of recommendations to the miner. The developed system is still undergoing further refinements and testing prior to being tested in an actual mine.

AI‐driven IoT‐fog analytics interactive smart system with data protection

AbstractIn recent decades, fog computing has contributed significantly to the expansion of smart cities. It generated numerous real‐time data and coped with time‐constraint applications. They use sensors, physical objects, and network standards to monitor health imaging, traffic surveillance, industrial management, and so forth. Interactive applications have been proposed for the Internet of Things (IoT) to control wireless channels and improve communication. However, most of the existing lack of handing network interference and a reliable monitoring process. Moreover, many solutions are vulnerable to external threats, resulting in inconsistent and untrustworthy information for end users. Thus, this article proposes a framework that considers possible shortest paths to provide the most reliable and low‐latency healthcare decision system using Q‐learning. In addition, fog devices offer a trusted transmission interference system and are kept secure. The proposed framework is specially designed for rapid real‐time medical data processing while enforcing robust security throughout the IoT‐based transmission process. To identify the health sensors in pairwise objects with the initial computing cost, the proposed framework applies graph theory. It also extracts the most effective and least loaded communication edges by examining the behaviour of devices. Moreover, the identities of devices are verified using lightweight timestamps and secret information, accordingly, it decreases the privacy threats.

Environment‐aware intelligent numerology control approach for 5G and beyond systems

Summary5G and beyond (5GB) systems show a flexible characteristic to meet different user communications requirements in parallel. Multi‐numerology waveform design is an important part of this human centric characteristic, however, it is necessary to make multi‐numerology planning. In this paper, the integrated sensing and communications (ISAC) concept is used with machine learning (ML) techniques to develop an intelligent numerology control mechanism for 5GB. Thanks to the ISAC capabilities, an environment‐aware system is designed, and several useful sensing information (USI) that affect the wireless channel characteristic is utilized. It is assumed that the USI is obtained through 5GB smart city networks. At that point, synthetic data generation is performed to form a new dataset with USI‐based features. Additionally, a novel feature control algorithm is proposed in the paper. Lastly, simulation results are presented for different type of ML models including several ensemble methods.

The Media's Influence on Uganda's Security Sector Reforms: An Analysis of a Few Broadcast and Print Media Stations in Kampala

The goal of this study was to investigate how the media and other external variables influenced Uganda's security sector reform. The study especially looked at the several ways that Uganda's media shaped the country's security sector reforms, noted the difficulties that the media in Uganda experienced in implementing these reforms, and determined the other elements that affected Uganda's security sector reform. The study population included Kampala city residents, security personnel, and media personnel. This study used a quantitative, descriptive, and correlative research approach to investigate how the media and other factors shaped the security sector changes. Conversely, a qualitative method was applied to evaluate the difficulties encountered by the media, involving the collection of data through in-depth interviews with journalists. According to the study's findings, the mass media—that is, radio, television, and print—accounted for 47.9% of the security sector's performance (adjusted R2 = 0.479). This indicates that other factors not taken into consideration by this model accounted for 52.1% of the contribution. Nonetheless, just two media outlets—radio (β = 0.568, p = 0.000 < 0.05) and television broadcasting (β = 0.271, p = 0.004 < 0.05)—had a positive and noteworthy impact on the security sector's performance in Uganda, whereas print media (β = -0.090, p = 0.312 < 0.05) had a negative and negligible impact. The results of the journalist interviews also showed that, despite the media's beneficial influence on the performance of the security sector, the media in Uganda has certain obstacles to reforming the security sector. The primary obstacles identified by the interviewees were the absence of legal provisions or instruments that enable journalists to obtain information, coupled with the preservation of antiquated laws on statute books that restrict access, bureaucratic red tape in government, insufficient funding and institutional bureaucracy, political violence, and inadequate training. The results of the study showed that, as 45.2% of the data showed, there is a positive correlation between the other parameters and the performance of the security sector (p = 0.05). These other elements include company culture, resource availability, and leadership. This means that, despite a number of restrictions and laws put in place by governments to restrict media impact, the Ugandan media does its function. The study also comes to the conclusion that performance in the security industry is influenced by other factors. The report suggests that in order to enhance their effectiveness, the UPDF and UPF, which are the main security agencies, should rebrandtheir organizational culture, leadership, and structure. Keywords: Media, security sector, Uganda, Broadcast, Reform

Delta-sigma modulation supporting the 4194304QAM dual polarization signal at the W-band transmission over a 4.6 km wireless distance.

In this Letter, we propose a dual-polarized coherent millimeter-wave system based on differential delta-sigma modulation (D-DSM) intended for long-distance wireless transmission in the W-band. The proposed system can transmit polarization-division-multiplexed (PDM) D-DSM signals with modulation orders up to 4194304QAM over a wireless channel for 4.6 km at a signal baud rate of 20 G. After 4.6 km of wireless transmission, we successfully achieve a bit error rate (BER) lower than the hard-decision forward error correction (HD-FEC) of 3.8 × 10-3 for 34.51 Gbit/s PDM-524288QAM and a BER lower than the soft-decision forward error correction (SD-FEC) of 4.2 × 10-2 for 32.23 Gbit/s PDM-4194304QAM.

Listening to Cairo: British radio monitoring and intelligence gathering, c. 1953-1967

ABSTRACT This article examines the BBC’s radio monitoring service, its relationship with Whitehall, and the CIA’s Foreign Broadcasting Information Service (FBIS). Radio monitoring was invaluable for analysing broadcasting in states, such as in Egypt, where the media became state controlled. Listening to radio broadcasts provided invaluable open-source intelligence concerning internal economic and political developments that might have been difficult to collect by more orthodox mechanisms. This article focuses on Anglo-American monitoring of Egyptian ‘political’ broadcasts by Sawt al-Arab (Voice of the Arabs) that were widely listened to across the Middle East and East Africa. Egyptian transmissions were characterised by their hostility to Britain’s allies and interests in Iraq, Jordan, and the Persian Gulf, which explains why they were examined in detail by the Joint Intelligence Committee. The evidence shows radio monitoring reports were invaluable for officials on the ground and in Whitehall, but the impact of intelligence analysis of Egypt’s intentions on high level decision making in Whitehall is contestable.

RCS measurement and ISAR imaging radar in VHF/UHF radio channels

ABSTRACT The Radar Cross Section (RCS) plays a crucial role in radar systems, serving to detect and characterize radar targets. Moreover, the need to penetrate foliage and capture images of man-made structures like roads and buildings has driven the development of very high frequency/ultra high frequency (VHF/UHF)-based radar systems. In this context, we propose a novel polyphase-coded spread spectrum (PCSS) radar system designed for RCS measurements and ISAR imaging over VHF/UHF radio channels in open environments. To provide a comprehensive understanding, we examined the open range, considering factors such as amplitude distribution function, root mean square (RMS) delay, and coherence bandwidth, followed by a link budget analysis. We also conducted a comparative study of RCS measurements to evaluate the performance of the proposed radar system, demonstrating its effectiveness through theoretical calculations. Furthermore, we assessed the radar imaging capabilities by applying the CLEAN algorithm to improve the quality of the generated images.

Tambov radio: from wired access points to Internet broadcasting

INTRODUCTION. The study focuses on regional radio, which is an important part of the modern information system due to the stable interest in radio on the Internet, ease of use, and accessible forms of informing the audience. Analysis of radio broadcasting formation in the Tambov region, identification of characteristic features of radio activity in different historical eras, assessment of the current state of development of electronic media is the goal of this study.MATERIALS AND METHODS. The study is used comparative historical analysis, a systematic method, the method of expert interviews, and analyzed extensive empirical audio material, articles in the media, and local history documents.RESULTS AND DISCUSSION. The periodization of radio from the beginning of the Tambov region radioification to the development of Internet radio is presented, highlighting the key stages of the functioning of this media in the region. The experience of public and private radio broadcasting is generalized, the originality of the development of Tambov radio journalism is reflected, and the concept of viewing the media as an integral system, including structural elements and characteristic patterns is formed.CONCLUSION. The results of the study may be useful for further study of electronic media in the Tambov region in the context of the overall development of the modern media system of the region and the country as a whole.

Spatial de-correlation of generated keys from wireless channels using adversarial deep learning

Spatial de-correlation of generated keys from wireless channels using adversarial deep learning

TCP Stratos for stratosphere based computing platforms

Stratosphere computing platforms (SCPs) benefit from free cooling but face challenges necessitating transmission control protocol (TCP) re-design. The redesign should be considered due to stratospheric gravity waves (SGWs), and sudden stratospheric warming (SSWs). SGWs, and SSWs disturb the wireless channel during SCPs packet communications. SCP packet transmission can be done using existing TCP variants at the expense of high packet loss as existing TCP variants do not consider SGWs, and SSWs. TCP variants designed for satellite links are not suitable as they do not explicitly consider the SSW, and SGW. Moreover, the use of SCPs in future internet is at a nascent stage. The presented research proposes a new TCP variant i.e., TCP Stratos. TCP Stratos incorporates a parameter transfer mechanism and comprises loss-based; and delay-based components. However, its window evolution considers the occurrence of SSWs, and SGWs. The performance benefit of the proposed approach is evaluated via MATLAB numerical simulation. MATLAB simulation has been used because of the consideration of the stratosphere. The modelling of the stratosphere in this case is challenging for conventional tools and frameworks. Performance evaluation shows that using TCP Stratos instead of existing TCP variants and improved TCP variants reduces the packet loss rate by an average of (7.1–23.1) % and (3.8–12.8) %, respectively. The throughput is enhanced by an average of (20.5–53)%, and (40.9–70)% when TCP Stratos is used instead of existing TCP variant and modified TCP variant, respectively.

Enhanced Dwarf Mongoose optimization algorithm with deep learning-based attack detection for drones

Security in smart cities is a challenging issue in urban environments as they depend upon interconnected technologies and data for effective services. To address security challenges, smart cities implement robust cybersecurity measures, including network monitoring, encryption, and intrusion detection systems. Detecting and mitigating possible security risks in drone network B5G is a crucial aspect of ensuring reliable and safe drone operation. It is necessary to establish sophisticated and robust attack detection techniques to defend against security threats as the use of drones becomes increasingly widespread and their applications diversify. This is due to the lack of privacy and security consideration in the drone’s system, including an inadequate computation capability and unsecured wireless channels to perform advanced cryptographic algorithms. Intrusion detection systems (IDS) and anomaly detection systems can identify suspicious activities and monitor network traffic, such as anomalous communication patterns or unauthorized access attempts. Therefore, the study presents an enhanced dwarf mongoose optimization algorithm with deep learning-based attack detection (EDMOA-DLAD) in Networks B5G for the purpose of Drones technique. The presented EDMOA-DLAD technique aims to recognize the attacks and classifies them on the drone network B5G. Primarily, the EDMOA-DLAD technique designs a feature selection (FS) approach using EDMOA. To detect attacks, the EDMOA-DLAD technique uses a deep variational autoencoder (DVAE) classifier. Finally, the EDMOA-DLAD technique applies the beetle antenna search (BAS) technique for the optimum hyperparameter part of DVAE model. The outcome of EDMOA-DLAD approach can be verified on benchmark datasets. A wide range of simulations inferred that the EDMOA-DLAD method obtains enhanced performance of 99.79% over other classification techniques.

Применение физического уровня 5G NR в космических коммуникациях, оценка эффективности.

The propagation channel is significantly modified in the case of 5th Generation New Radio radio access technology (5G NR) in space communication systems. In particular, large delays occur with respect to the terrestrial propagation channel, and signal attenuation increases, resulting in a lower signal-to-noise ratio (SNR). The Doppler shift of the carrier frequency is also significantly increased due to the high velocity of the spacecraft (SC) relative to the user equipment (UE). The aim of the work is to investigate the decoding capability of the physical channels and signals of the 5G NR system in case of its application in satellite communication systems (SCS), as well as to calculate the performance of such a system to assess the applicability of 5G NR in SCS. The ability to correctly decode signals and channels depending on SNR is evaluated using mathematical modelling of 5G NR signal and channel shaping in conjunction with the Quasi Deterministic Radio Channel Generator (QuaDRiGa) model. The research within the paper draws conclusions on the applicability of 5G NR radio access technology in a space communications environment.

The British Royals in Australia

The British Royals in Australia