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Brasilia, Brazil

The National Telecommunications Agency is a special agency in Brazil created by the general telecommunications act in 1997 and governed by Decree 2338 of 07/10/1997. The agency is administratively and financially independent, and not hierarchically subordinate to any government agency. Its decisions can only be appealed in court. From the Ministry of Communications, Anatel has inherited the powers of granting, regulating and supervising telecommunications in Brazil as well as much technical expertise and other material assets. Wikipedia.

Silva H.V.L.,Federal University of Goais | Lemos R.P.,Federal University of Goais | Ferreira Y.R.,Anatel | Guedes L.G.R.,Pontifical Catholic University of Goias
Signal Processing | Year: 2013

The former SEAD method was recently proposed by the authors and showed maximum likelihood performance in resolving closely located DOA (direction of arrival) angles at low signal-to-noise ratios (SNR). However, it required a prohibitively high computational effort. We propose a new estimate selection strategy inspired on branch-and-bound in order to reduce the computational effort of SEAD. Equations of computational cost were derived and validated for both SEAD versions. Also, we introduced an adaptive strategy that detects the signal peaks and estimates the amount of signal sources grouped in each peak. Experimental results demonstrated that the proposed strategy dramatically reduced the computational effort and yielded an improved SEAD. Compared to MODEX, improved SEAD showed competitive runtime and its root mean square error (RMSE) performance attained the Cramér-Rao lower bound (CRLB) up to SNR=-12 dB, 8 dB lower than that of MODEX. Also, computational effort grew slower for improved SEAD than for MODEX, as the number of sources was increased. © 2012 Elsevier B.V. All rights reserved. Source

Rodrigues E.J.B.,Federal University of Rio Grande do Norte | Rodrigues E.J.B.,Anatel | D'Assuncao A.G.,Federal University of Rio Grande do Norte | Lins H.W.C.,Federal University of Rio Grande do Norte | Peixeiro C.,University of Lisbon
Microwave and Optical Technology Letters | Year: 2016

In this paper a coplanar waveguide (CPW) fed ultra-wideband (UWB) circular ring monopole antenna with a modified ground plane is proposed. The dimensions of the antenna are obtained using a genetic algorithm (GA) optimization procedure. To proof the concept and validate the design antenna prototypes have been fabricated and tested. A good agreement is obtained between numerical simulation and experimental results. The input reflection coefficient is below -10 dB in the frequency range 2.52 GHz to 12 GHz, which corresponds to an impedance bandwidth of about 4.8:1, and the gain is about 3 dBi. The proposed antenna element seems to be suitable for UWB and cognitive radio spectrum sensing applications. © 2016 Wiley Periodicals, Inc. Source

Purpose - This article introduces the reader to the paradigmatic revolution performed by Big Data, and encourages imagining how jurisprudence and the law can deal with the challenges that will result from modernity of technology. Methodology/approach/design - It was composed from bibliographic research aimed at explaining the Big Data phenomenon and challenging its implications on the law, in light of the theory of Immanuel Wallerstein on modernity. Findings - The main features of the novel phenomenon of Big Data are presented with emphasis on the potential harmful implications for democratic participation in theregulatory process, in order to relate them to the concepts of modernity of technology and modernity of liberation developed by Immanuel Wallerstein. Practical implications - The article serves as an invitation to the researcher interested in the impact of modernity of technology in the legal institutions that modulate and legitimate the regulatory process, with special focus on Big Data. Originality/value - It innovates in the Brazilian legal research to the extent that it assists in delving the implications of Big Data in Portuguese speaking literature. Source

Rodrigues E.J.B.,Federal University of Rio Grande do Norte | Rodrigues E.J.B.,Anatel | Lins H.W.C.,Federal University of Rio Grande do Norte | D'Assuncao A.G.,Federal University of Rio Grande do Norte
IET Microwaves, Antennas and Propagation | Year: 2016

The synthesis of a simple electronically reconfigurable annular ring monopole antenna using a designing optimisation process based on particle swarm optimisation (PSO) and artificial bee colony (ABC) algorithms is proposed. Several antenna dimensions are selected as objective functions of PSO and ABC and their best solutions are considered as the optimised dimensions of the antenna geometry. Two radio-frequency p-i-n diodes, connecting the antenna feeding line to two microstrip stubs are used to change the antenna frequency response from ultra-wideband (UWB), from 3.1 to 10.6 GHz, to narrowband (NB) operation about 5.8 GHz. The antenna design and simulation are performed using Ansoft high-frequency structure simulator software. PSO and ABC algorithms are written in Java language. Thereafter, antenna prototypes are fabricated and measured for validation purposes. Simulation and measurement results are obtained showing good agreement. The measured optimised impedance bandwidths of the UWB and NB bands are up to 128 and 23%, respectively. Additionally, simulated and measured radiation patterns are very similar when the reconfigurable antenna is operating in OFF-state (UWB sensing antenna) and in ON-state (NB transmitting antenna) modes, indicating the proposed antenna geometry as a promising candidate for applications such as UWB and cognitive radio. © The Institution of Engineering and Technology. Source

Ferreira Y.R.,Anatel
IEEE ISPLC 2010 - International Symposium on Power Line Communications and its Applications | Year: 2010

Electromagnetic waves irradiated from Broadband Power Line (BPL) have frequency rangse that overlaps with other radiocommunication services. Anatel Resolution no 527 published in 8 March 2009 establishes the limits for electric field levels to BPL, which makes it possible to share the spectrum with other telecommunication services. The aim of this paper is to compare the results of measurement systems, which can be used in the inspection processes to search for unwanted emissions from BPL systems that are above the established limits. The first inspection tool is a mobile monitoring station, with an active antenna to get the HF signal band, and the other is a set-up with a spectrum analyzer plus loop antenna. ©2010 IEEE. Source

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