201 research outputs found
Elisabeth de Austria : la mirada de una emperatriz de incógnito
Elísabeth de Austria (1837-1898) no pudo escapar a su destino de emperatriz y reina, pero eso no la detuvo en la búsqueda de la libertad que anhelaba y que desató la crítica de la sociedad vienesa. La artifícialidad y los intereses cortesanos tan diferentes a los suyos, hicieron que escapara cada vez más lejos y durante más tiempo. A los 22 años, seis después de su matrimonio, luego de haber dado a luz al heredero, y por una serie de desavenencias con su marido, comenzó la búsqueda de su individualidad y ya no se detuvo. Madeira, Corfú, Venecia, las termas de Austria y Alemania, su amada Hungría, las ruinas de Grecia y la pasión por los lugares que vieron al legendario Aquiles la llevaron de uno a otro lado. La escritura de sus poemas comenzó cuando ya casi contaba 50 años, y por cuatro años consecutivos llevó un Diario Poético que quedó inconcluso cuando su hijo fue encontrado muerto en Mayerling. Son poemas que denuncian la caducidad de la monarquía, la corrupción de la corte, la falta de amor y comprensión, y que logran su efecto cuando Elísabeth describe los lugares que la conectan con la naturaleza del mundo.Elísabeth of Austria (1837-1898) could not escape from her destiny of empress and queen, but that did not stop her. Her search for freedom was the reason of the Viennese court critic. The artifíciality and the courtesans' interests were so different to hers; consequently, she escapeó so far and so long. When she was 22, six years after her marriage, she became the mother of the heir. Because of a series of disagreements with her husband, the search of her individuality began and did not stop. Madeira, Corfú, Venice, the hot springs of Austria and Germany, his loved Hungary, the ruins of Greece and the passion by the places that saw the legendary Aquilles took herseif from one place to another. The writing of her poems began when she was almost 50, and for four consecutive years she wrote a poetic diary that was unfinished when her son was found dead in Mayerling. They are poems that denounce the lapsing of the monarchy, the corruption of the court, and the absence of love and understanding. They reach their effect when Elísabeth describes the places that connect her with the world's nature.Fil: Garello, Mariana G..
Universidad Nacional de Córdob
Implementation of 5G beamforming techniques on cylindrical arrays
In this paper we study the performance of a Uniform Cylindrical Array for a 5G base station working in the mmW region. Conventional and Capon beamforming design are considered. A comparison against a base station equipped with three Uniform Planar Arrays, one per sector, is presented. Average per-user achievable rate results are provided with different system configuration in terms of network loading and number of antennas, showing that Uniform Cylindrical Array could represent an interesting solution for 5GmmW networks
Assessment of MU-MIMO schemes with cylindrical arrays under 3GPP 3D channel model for B5G networks
Beyond 5G technologies promise groundbreaking advances on the performance of cellular networks, by taking advantage of Massive MIMO in mmWave scenarios. The aim of this study is to analyze and test the performance of a 5G cell site equipped with large antenna arrays. It is of particular interest the comparison between the typical trisector cell design with a planar array for each sector, and the less investigated cylindrical array, able to maintain a constant pattern through the whole azimuthal range. To validate our analysis, we adopt the latest 3GPP-compliant 3D channel model and we evaluate the performance of multi-user and multi-layer precoding and combining schemes. Several MIMO configurations are taken into account, and we show that cylindrical arrays can improve the overall system performance, both in terms of achievable per-user rate and outage probability
A Novel Deep Learning Approach to CSI Feedback Reporting for NR 5G Cellular Systems
In this paper, we study 5G Channel State Information
feedback reporting. We show that a Deep Learning approach
based on Convolutional Neural Networks can be used to learn
efficient encoding and decoding algorithms. We set up a fully
compliant link level 5G-New Radio simulator with clustered delay
line channel model and we consider a realistic scenario with
multiple transmitting/receiving antenna schemes and noisy downlink
channel estimation. Results show that our Deep Learning
approach achieves results comparable with traditional methods
and can also outperform them in some conditions
Software-Defined Radio Implementation of a LoRa Transceiver
The number of applications of low-power wide-area networks (LPWANs) has been growing quite considerably in the past few years and so has the number of protocol stacks. Despite this fact, there is still no fully open LPWAN protocol stack available to the public, which limits the flexibility and ease of integration of the existing ones. The closest to being fully open is LoRa; however, only its medium access control (MAC) layer, known as LoRaWAN, is open and its physical and logical link control layers, also known as LoRa PHY, are still only partially understood. In this paper, the essential missing aspects of LoRa PHY are not only reverse engineered, but also, a new design of the transceiver and its sub-components are proposed and implemented in a modular and flexible way using GNU Radio. Finally, some examples of applications of both the transceiver and its components, which are made to be run in a simple setup by using cheap and widely available off-the-shelf hardware, are given to show how the library can be used and extended
Implementation of Deep-Learning-Based CSI Feedback Reporting on 5G NR-Compliant Link-Level Simulator
Advances in machine learning have widened the range of its applications in many fields. In particular, deep learning has attracted much interest for its ability to provide solutions where the derivation of a rigorous mathematical model of the problem is troublesome. Our interest was drawn to the application of deep learning for channel state information feedback reporting, a crucial problem in frequency division duplexing (FDD) 5G networks, where knowledge of the channel characteristics is fundamental to exploiting the full potential of multiple-input multiple-output (MIMO) systems. We designed a framework adopting a 5G New Radio convolutional neural network, called NR-CsiNet, with the aim of compressing the channel matrix experienced by the user at the receiver side and then reconstructing it at the transmitter side. In contrast to similar solutions, our framework is based on a 5G New Radio fully compliant simulator, thus implementing a channel generator based on the latest 3GPP 3-D channel model. Moreover, realistic 5G scenarios are considered by including multi-receiving antenna schemes and noisy downlink channel estimation. Simulations were carried out to analyze and compare the performance with current feedback reporting schemes, showing promising results for this approach from the point of view of the block error rate and throughput of the 5G data channel
Regenerative approaches for V/UHTS feeder links: system analysis and on-board complexity reduction
The dramatically increasing demand for high data rates necessitates the proper dimensioning of the feeder links of very or ultra high throughput satellite (V/UHTS) systems. However, because most of the current solutions rely on transparent payloads, the deployment of a very large number of spatially separated ground stations is necessary to support the total system bandwidth by enabling a full reuse of the scarce available uplink bandwidth. This approach has a significant impact on the complexity and the costs of the ground segment infrastructure. Regenerative payloads could be considered to avoid this design bottleneck. By allowing demodulation and decoding on-board the satellite, the favourable link budget conditions of feeder links compared to the user links can be exploited. Using a spectral efficient transmission technique, the number of ground stations required to support a target sum throughput can be notably reduced. Meanwhile, regenerative solutions have until now barely been used in V/UHTS payloads due to their high on-board power consumption. As a consequence, candidate solutions are proposed in this work to overcome this limitation. A non-coherent modulation technique, known as Differential Amplitude Phase Shift Keying (DAPSK), is introduced to avoid on-board carrier synchronization. Moreover, polar codes are considered to minimize the power consumption of the channel decoder. A preliminary analysis of the expected on-board power consumption compared to that of a standard DVB-S2 approach is conducted using available results in the open literature. Link performance is also evaluated via numerical simulations
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