Listar GI-GTEC - Artigos por título
Mostrando ítems 49-68 de 186
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Beam Reconfiguration of Linear Arrays Using Parasitic Elements
(The Institution of Engineering and Technology, 2006-02-13)[Abstrac] An innovative method for linear arrays beam reconfiguration is presented. This pattern reconfigurability is achieved by a mechanical displacement of a parasitic array located in front of an active one. Two worked ... -
Bit Error Probability and Capacity Bound of OFDM Systems in Deterministic Doubly-Selective Channels
(Institute of Electrical and Electronics Engineers, 2020-10)[Abstract]: Doubly-selective channels, such as those that occur when the transmitter and the receiver move relative to each other at high speeds, are a key scenario for fifth generation (5G) cellular systems, which are ... -
Blind channel identification in Alamouti coded systems: a comparative study of eigendecomposition methods in indoor transmissions at 2.4 GHz
(Wiley, 2008)[Abstract]: This paper focuses on blind channel estimation in Alamouti coded systems with one receiving antenna working in indoor scenarios where the flat fading assumption is reasonable. A comparative study of several ... -
Broadband Access in Complex Environments: LTE on Railway
(Institute of Electronics, Information and Communication Engineers, 2014)[Abstract]: This paper assesses the main challenges associated with the propagation and channel modeling of broadband radio systems in a complex environment of high speed and metropolitan railways. These challenges comprise ... -
Building Decentralized Fog Computing-Based Smart Parking Systems: From Deterministic Propagation Modeling to Practical Deployment
(Institute of Electrical and Electronics Engineers, 2020-06-25)[Abstract] The traditional process of finding a vacant parking slot is often inefficient: it increases driving time, traffic congestion, fuel consumption and exhaust emissions. To address such problems, smart parking systems ... -
Calculating Directivities with the Two-Dimensional Simpson's Rule
(Institute of Electrical and Electronics Engineers, 2004-08)[Abstract] C++ routines implementing the simple generalization of Simpson's rule to two dimensions for calculating antenna directivities compare well with methods currently available in common symbolic and numerical ... -
Calculation of the Connected Dominating Set Considering Vertex Importance Metrics
(M D P I AG, 2018-01-28)[Abstract] The computation of a set constituted by few vertices to define a virtual backbone supporting information interchange is a problem that arises in many areas when analysing networks of different natures, like ... -
Channel Estimation and Hybrid Precoding for Frequency Selective Multiuser mmWave MIMO Systems
(IEEE, 2018-05)[Abstract]: Configuring the hybrid precoders and combiners in a millimeter wave multiuser multiple-input multiple-output system is challenging in frequency selective channels. In this paper, we develop a system that uses ... -
Channel estimation techniques for linear precoded systems: Supervised, unsupervised, and hybrid approaches
(Elsevier, 2011-07)[Abstract] Linear precoding is an attractive technique to combat interference in multiple-input multiple-output systems because it reduces cost and power consumption at the receiver. Frequency division duplex systems with ... -
Circularly Polarized Arrays of Sequentially Crossed Dipoles
(Genxcellence Software Pvt. Ltd., 2013-11)[Abstract] Usual configurations of dipoles that radiate circularly polarized fields consist of elements arranged in crossed pairs, with one component of each pair in top of the other component. As an alternative to this, ... -
Clock frequency Impact on the performance of high-security cryptographic cipher suites for energy-efficient resource-constrained IoT devices
(M D P I AG, 2018-12-20)[Abstract] Modern Internet of Things (IoT) systems have to be able to provide high-security levels, but it is difficult to accommodate computationally-intensive cryptographic algorithms on the resource-constrained hardware ... -
Coded Aperture Hyperspectral Image Reconstruction
(MDPI, 2021)[Abstract] In this work, we study and analyze the reconstruction of hyperspectral images that are sampled with a CASSI device. The sensing procedure was modeled with the help of the CS theory, which enabled efficient ... -
Combining Switched TMAs and FDAs to Synthesize Dot-Shaped Beampatterns
(Institute of Electrical and Electronics Engineers, 2021)[Abstract]: The application of frequency offsets to the elements of a conventional phased array with variable phase shifters (VPSs) leads to frequency diverse arrays (FDAs) with the ability to provide range-angle spatial ... -
Creating the Internet of Augmented Things: An Open-Source Framework to Make IoT Devices and Augmented and Mixed Reality Systems Talk to Each Other
(MDPI AG, 2020-06-11)[Abstract] Augmented Reality (AR) and Mixed Reality (MR) devices have evolved significantly in the last years, providing immersive AR/MR experiences that allow users to interact with virtual elements placed on the real-world. ... -
DASBE: Decision-Aided Semi-Blind Equalization for MIMO Systems with Linear Precoding
(Akademie Ved Ceske Republiky * Ustav Informatiky, 2010)[Abstract] Multiple-Input Multiple-Output (MIMO) digital communications standards usually acquire Channel State Information (CSI) by means of supervised algorithms, which implies a loss of performance since pilot symbols ... -
Deep Contextual Bandit and Reinforcement Learning for IRS-Assisted MU-MIMO Systems
(Institute of Electrical and Electronics Engineers, 2023-07)[Abstract]: The combination of multiple-input multiple-output (MIMO) systems and intelligent reflecting surfaces (IRSs) is foreseen as a critical enabler of beyond 5G (B5G) and 6G. In this work, two different approaches ... -
Design and Empirical Validation of a Bluetooth 5 Fog Computing Based Industrial CPS Architecture for Intelligent Industry 4.0 Shipyard Workshops
(Institute of Electrical and Electronics Engineers, 2020-03-04)[Abstract] Navantia, one of largest European shipbuilders, is creating a fog computing based Industrial Cyber-Physical System (ICPS) for monitoring in real-time its pipe workshops in order to track pipes and keep their ... -
Design and Experimental Validation of a LoRaWAN Fog Computing Based Architecture for IoT Enabled Smart Campus Applications
(MDPI AG, 2019-07-26)[Abstract] A smart campus is an intelligent infrastructure where smart sensors and actuators collaborate to collect information and interact with the machines, tools, and users of a university campus. As in a smart city, ... -
Design and Experimental Validation of an Augmented Reality System With Wireless Integration for Context Aware Enhanced Show Experience in Auditoriums
(Institute of Electrical and Electronics Engineers, 2020-12-30)[Abstract] The development of multiple cultural and social related activities, such as shows related with the performing arts, conferences or presentations rely on facilities such as auditoriums, theatres and conference ... -
Design and implementation of an OFDMA-TDD physical layer for WiMAX applications
(SpringerOpen & European Association for Signal Processing, 2013)[Abstract]: This work describes the design, implementation, and performance evaluation of an orthogonal frequency division multiple access (OFDMA) time-division duplexing (TDD) physical layer (PHY) compliant with the ...
