Wireless Networks
Mostrando 1-12 de 195 artigos, teses e dissertações.
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1. Assessment of Total Attenuation and Adaptive Scheme for Quality of Service Enhancement in Tropical Weather for Satellite Networks and 5G Applications in Nigeria
Abstract The dynamic weather condition is a major concern for optimum channel utilization in recent times, especially at higher frequencies with larger bandwidth for 5G applications. Over the years, rain-induced attenuation among the hydrometeors has been linked as the major cause of signal impairment especially at the frequency, f ≥ 10 GHz. However, when
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2021-06
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2. FD MAC Protocol Design for Co-Existing WLANs in 5G Cellular Networks
Abstract In this paper, we design full-duplex (FD) medium access control (MAC) protocol for co-existing wireless local area networks (WLANs) in 5G cellular networks (WCFD-MAC). Our design considers some significant features of 5G networks, exceptionally, beamforming and FD capabilities at both, the base station and user equipment. FD communications may gener
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2021-03
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3. IEEE 802.11b/g Practical Assessment Using a Low-Cost Quasi-Yagi Rectenna for Indoor RF Energy Harvesting
Abstract This article presents an experimental analysis of the use of signals transmitted by Wireless Local Area Networks (WLAN) based on the IEEE 802.11b/g standards for Radio Frequency Energy Harvesting (RFEH) applications in indoor environments employing a Quasi-Yagi Rectenna (QYR) topology. This analysis is a crucial point to distinguish the use of the I
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2021-03
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4. Um Modelo Matemático para Estimativas do Consumo de Energia em Redes de Sensores Visuais sem Fio
RESUMO As redes de sensores sem fio alcançaram um papel de destaque no cenário atual das novas tecnologias de comunicação, centradas em aplicações de Internet das Coisas e Cidades Inteligentes, sobretudo quando câmeras são utilizadas para obter dados visuais do ambiente monitorado. Nessas redes, questões de eficiência energética são centrais, uma
TEMA (São Carlos). Publicado em: 16/09/2019
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5. Adaptive Filtration of Parameters of the UAV Movement Based on the TDOA-Measurement Sensor Networks
ABSTRACT: In modern conditions unmanned aerial vehicles (UAVs) generate new classes of threats, including their use for terrorist purposes. A feature of modern UAVs is the ability to perform sudden maneuvers and to keep the same position in the point in space. For the description of the UAV movement with various types of maneuver it is used a rectangular coo
J. Aerosp. Technol. Manag.. Publicado em: 26/08/2019
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6. Energy Efficient Rate Adaptation Algorithm for FiWi Access Network
Abstract Similar to any telecommunication network, energy efficiency is a desirable feature for fiber wireless (FiWi) access networks. These networks have optical back end and wireless front end. Both ends may contribute for energy efficiency. This work focuses on front end of FiWi access network, which is IEEE 802.11a wireless local area network (WLAN). For
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2017-12
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7. COST-EFFECTIVE BANDWIDTH PROVISIONING IN MICROWAVE WIRELESS NETWORKS UNDER UNRELIABLE CHANNEL CONDITIONS
ABSTRACT Cost-effective planning and dimensioning of backhaul microwave networks under unreliable channel conditions remains a relatively underexplored area in the literature. In particular, bandwidth assignment requires special attention as the transport capacity of microwave links is prone to variations due to, e.g., weather conditions. In this paper, we f
Pesqui. Oper.. Publicado em: 2017-09
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8. AN OPTIMIZATION MODEL TO MINIMIZE THE EXPECTED END-TO-END TRANSMISSION TIME IN WIRELESS MESH NETWORKS
ABSTRACT Time metrics are extremely important to evaluate the transmission performance on Wireless Mesh Networks (WMNs), whose main characteristic is to use multihop technology to extend the network coverage area. One of such metrics is WCETT (Weighted Cumulative Expected Transmission Time), in which transmission times per hop are weighted for both proactive
Pesqui. Oper.. Publicado em: 2017-08
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9. Optically controlled reconfigurable antenna for 5G future broadband cellular communication networks
Abstract This paper presents an optically controlled reconfigurable antenna for millimetre-wave frequency range. Silicon switches are used to control the optical reconfiguration, modifying the frequency response and radiation pattern of the antenna design. Therefore, the system can switch between the lightly licensed 28 GHz and 38 GHz frequency bands, useful
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2017-03
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10. Fuzzy Based Mobility Management in 4G Wireless Networks
ABSTRACT Handover is the key procedure in wireless networks to provide required qual ity of service to the users during mobility Handover. As the current scenario of wireless communication comprises of heterogeneity in architecture, application and radio access technologies concentrating on vertical handover becomes important to provide continuous communicat
Braz. arch. biol. technol.. Publicado em: 23/01/2017
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11. Energy Efficient Clustering in Multi-hop Wireless Sensor Networks Using Differential Evolutionary MOPSO
ABSTRACT The primary challenge in organizing sensor networks is energy efficacy. This requisite for energy efficacy is because sensor nodes capacities are limited and replacing them is not viable. This restriction further decreases network lifetime. Node lifetime varies depending on the requisites expected of its battery. Hence, primary element in constructi
Braz. arch. biol. technol.. Publicado em: 23/01/2017
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12. A Performance Evaluation of WLAN-Femtocell-LTE beyond the Capacity Crunch. Does Femtocell have to overcome WLAN or can they coexist in HetNets?
Abstract This paper originates from a practical experiment based on Mesh Networks. The promising results obtained from this experiment prompted us to discuss in greater depth whether Wireless Local Area Networks (WLAN) are still useful for current communications. This means that on the one hand femtocells can be defined as small base stations that use the sa
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2016-12