The rapid increase in data traffic caused by the proliferation of smart devices has spurred the demand for extremely large-capacity wireless networks. Thus, faster data transmission rates and greater spectral efficiency have become critical requirements in modern-day networks. The ubiquitous 5G is an end-to-end network capable of accommodating billions of linked devices and offering high-performance broadcast services due to its several enabling technologies. However, the existing review works on 5G wireless systems examined only a subset of these enabling technologies by providing a limited coverage of the system model, performance analysis, technology advancements, and critical design issues, thus requiring further research directions. In order to fill this gap and fully grasp the potential of 5G, this study comprehensively examines various aspects of 5G technology. Specifically, a systematic and all-encompassing evaluation of the candidate 5G enabling technologies was conducted. The evolution of 5G, the progression of wireless mobile networks, potential use cases, channel models, applications, frequency standardization, key research issues, and prospects are discussed extensively. Key findings from the elaborate review reveal that these enabling technologies are critical to developing robust, flexible, dependable, and scalable 5G and future wireless communication systems. Overall, this review is useful as a resource for wireless communication researchers and specialists.
Radio waves are attenuated by atmospheric phenomena such as snow, rain, dust, clouds, and ice, which absorb radio signals. Signal attenuation becomes more severe at extremely high frequencies, usually above 10 GHz. In typical equatorial and tropical locations, rain attenuation is more prevalent. Some established research works have attempted to provide state-of-the-art reviews on modeling and analysis of rain attenuation in the context of extremely high frequencies. However, the existing review works conducted over three decades (1990 to 2022), have not adequately provided comprehensive taxonomies for each method of rain attenuation modeling to expose the trends and possible future research directions. Also, taxonomies of the methods of model validation and regional developmental efforts on rain attenuation modeling have not been explicitly highlighted in the literature. To address these gaps, this paper conducted an extensive literature survey on rain attenuation modeling, methods of analyses, and model validation techniques, leveraging the ITU-R regional categorizations. Specifically, taxonomies in different rain attenuation modeling and analysis areas are extensively discussed. Key findings from the detailed survey have shown that many open research questions, challenges, and applications could open up new research frontiers, leading to novel findings in rain attenuation. Finally, this study is expected to be reference material for the design and analysis of rain attenuation.
Solar energy is the cleanest and most abundant form of energy that can be obtained from the Sun. Solar panels convert this energy to generate solar power, which can be used for various electrical purposes, particularly in rural areas. Maximum solar power can be generated only when the Sun is perpendicular to the panel, which can be achieved only for a few hours when using a fixed solar panel system, hence the development of an automatic solar tracking system. Over the years, different solar tracking systems have been proposed and developed, and a few have been reviewed in the literature. However, the existing review works have not adequately provided a comprehensive survey and taxonomies of these solar tracking systems to show the trends and possible further research direction. This paper aims to bridge these gaps by extensively reviewing these time-based solar tracking systems based on axis rotation and drive types. Lessons learned from the comprehensive review have been highlighted and discussed. Finally, critical open research issues are identified and elaborated.
1 January 2014 in Progress In Electromagnetics Research M
Electromagnetic wave propagation in arid and semi-arid regions is influenced by sand and dust storms. Meagre information has hitherto been reported as to the effect of storms on telecommunication systems operating in such regions. This paper presents a survey of current understanding of the wave propagation during storms. In this first part of the review-Part I, detailed parametric assessment of some electrical and mechanical properties affecting wave propagation in sand and dust storms is given. The second part of the review-Part II describes the principle of approach and technology adopted for the investigation highlighting both strengths and drawbacks. The results demonstrate that most authors have calculated signal attenuation effect, revealing that it is not very significant unless during severe storms. A few papers indicate the possibility of more significant cross polarisation. Part I explicitly gives an account of the sand and dust storms' phenomenon, reviews the storms' parameters affecting electromagnetic wave propagations and discusses the microwave and millimeter wave bands.
1 January 2014 in Progress In Electromagnetics Research M
Suspended particles in the atmosphere during sand and dust storms have numerous consequences on electromagnetic wave propagation in arid regions. The electromagnetic wave signal may suffer attenuation and cross polarization upon encounter with the suspended particles. However, meager information has hitherto been reported about effect of storms on the telecommunication systems operating in such regions. This paper presents a survey of current understanding of the electromagnetic wave propagation in sand and dust storms. A review of the literature covering electromagnetic scattering theory and applications is given. The review describes the principle of approach and technology adopted for the investigation highlighting both strengths and drawbacks. Detailed parametric assessment of the effects of storms on wave propagation as it concerns signal attenuation and cross polarization is also carried out. The results demonstrate that most authors have calculated the attenuation effect, revealing that it is not very significant unless very high suspended dust densities are assumed (i.e., during severe sand and dust storms). A few papers indicate the possibility of more significant cross polarisation. The obvious gap in knowledge of this field is finally also clearly established.