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CIGRE Session 46 2016年 2016-August卷

作者： Nascimento, Carlos A.M. Rosolem, Joao B. Dini, Danilo C. Hortencio, Claudio A. Aguiar, Joao Guilherme D. CEMIG - Companhia Energética de Minas Gerais Brazil CPqD Research and Development Center in Telecommunications Brazil

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Adaptive nonsymmetrical demodulation based on machine learning to mitigate time-varying impairments

Adaptive nonsymmetrical demodulation based on machine learni...

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2016 IEEE Avionics and Vehicle Fiber-Optics and Photonics Conference, AVFOP 2016

作者： Torres, Jhon J. Granada Chiuchiarelli, Andrea Thomas, Varghese A. Ralph, Stephen E. Soto, Ana M. Cardenas Gonzalez, Neil Guerrero Universidad de Antioquia GITA Research Group Calle 67 No 53-108 Medellín Colombia CPqD Foundation-Research and Development Center in Telecommunications CampinasSP 13086-902 Brazil School of Electrical and Computer Engineering Georgia Institute of Technology AtlantaGA30318 United States Tyndall National Institute Photonics System Group Lee Maltings Dyke Parade Cork Ireland

ISBN: (纸本)9781509015993

Future terabit optical communication systems will rely on higher order Quadrature Amplitude Modulation (QAM) formats to improve the spectral efficiency (SE). However, these formats exhibit a higher sensitivity to linear as well as non-linear impairments throughout the optical link [1, 2]. These impairments may be time-varying in nature arising from mechanical disturbance in optical fibers, temperature variations in the components and small variations of the bias control of the IQ optical modulators for example. Unlike optical noise, these degradations may have a probability density function (PDF) that is non-Gaussian and therefore may shift the centroids (mean value) of the received symbols from their ideal constellation positions by different extents, Fig 1a. Thus, employing non-symmetrical decision boundaries by means of machine learning techniques may improve the overall system performance with high computational efficiency in contradistinction to complex linear equalization or computationally heavy non-linear mitigation techniques [2, 3]. Furthermore, an area that has not been well explored is the use of digital techniques at the receiver for tracking and compensating the effects of fast time-varying link parameters. Here, we demonstrate an adaptive machine learning-based nonsymmetrical decision technique relying on clustering to mitigate time-varying impairments such as IQ imbalance, bias drift, and phase noise. We experimentally verified its effectiveness in a 16QAM Nyquist system at 16 Gbaud for back-to-back (B2B) and 250 km links. © 2016 IEEE.

关键词： Probability density function

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Challenges and current state of implementation of an IP platform for Brazil's ATM communications 15

Challenges and current state of implementation of an IP plat...

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2015 15th Annual Integrated Communication, Navigation and Surveillance Conference, ICNS 2015

作者： Nassif, Nadia A. Martins, Luciano Silva, Fernando C.C. Manoel, P. Dos S. Costa, Rodolfo S. Pacitti, Marcos De C. Belchior, Marcos A.V. CPqD - Research and Development Center in Telecommunications Campinas SP Brazil DECEA - Department of Air Space Control Rio de Janeiro RJ Brazil

ISBN: (纸本)9781479989522

This paper presents challenges and current implementation state of an IP platform to support ATM communications (Radio, Telephony, Surveillance Data, etc.) in the SISCEAB (Brazilian Integrated Airspace Control System) taking into account the national plan for CNS/ATM development. This IP platform comprises Voice Communication System (VCS), Ground Radio Stations (GRS) and Surveillance Systems (RADAR) based on IP Standards and Protocols as well as an IP/MPLS backbone to interconnect them. The paper describes the current scenario of Brazilian Aeronautical Telecommunication Network (ATN) as well as future scenarios and challenges to support the safe and gradual migration to a new infrastructure based on IP technology following EUROCAE (European Organisation for Civil Aviation Equipment) Standards and ICAO Recommendations. It also presents the basic infrastructure of the Information and Communications Systems Qualification Laboratory for SISCEAB (LQCEA) built at cpqd (a Brazilian Telecom research center) which will be used to test and validate the IP platform performance and equipment interoperability before they are deployed operationally. In addition, it presents an overview of the systemic tests executed to analyze and validate this new platform which have contributed to the project progress. Finally, this paper gives an overview about the next steps of ATN communications implementation in Brazil. © 2015 IEEE.

关键词： Interoperability

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Adaptive nonsymmetrical demodulation based on machine learning to mitigate time-varying impairments

Adaptive nonsymmetrical demodulation based on machine learni...

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IEEE Conference on Avionics Fiber-Optics and Photonics, AVFOP

作者： Jhon J. Granada Torres Andrea Chiuchiarelli Varghese A. Thomas Stephen E. Ralph Ana M. Cárdenas Soto Neil Guerrero González GITA Research Group Universidad de Antioquia Medellin CO CPqD Foundation???Research and Development Center in Telecommunications Campinas SP Brazil School of Electrical and Computer Engineering Georgia Institute of Technology Atlanta GA USA Photonics System Group Tyndall National Institute Cork Ireland

We proposed and experimentally demonstrated a machine learning-based nonsymmetrical demodulation technique for a DSP-enabled receiver, with the aim of enabling time-varying nonlinear mitigation. Experimental results showed that nonsymmetrical demodulation can reduce the SER by up to 0.7 decades, when assuming time frames consisting of 10 k symbols and fiber transmission of 250 km. The proposed technique is transparent to the specific source of nonlinearity, which makes it simple yet robust. This machine learning method may also allow simplification of the standard demodulation blocks in particular the equalizer. Employing short time windows for demodulation further enables inline optical monitoring, which is a valuable diagnostic tool for future terabit optical communication systems.

关键词： Optical noise Demodulation Signal to noise ratio Optical fiber communication Receivers Clustering algorithms

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development and performance analysis of a photonic-assisted RF amplifier

Development and performance analysis of a photonic-assisted ...

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SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference, IMOC 2015

作者： Cañas-Estrada, N. Arismar, Cerqueira S. Noque, D.F. Borges, R.M. Gonzalez, Neil Guerrero Oliveira, J.C.R.F. Laboratory WOCA National Institute of Telecommunications Santa Rita do SapucaíMG Brazil Research and Development Center of Telecommunications CPqD CampinasSP Brazil BrPhotonics CampinasSP Brazil

ISBN: (纸本)9781467394925

This work contributes to the area of microwave photonics applied to telecommunication systems in two ways. Initially, a photonic-assisted RF amplifier is proposed and experimentally validated. It takes advantage of the Four-wave Mixing (FWM) optical nonlinear effect, ensured by launching two high optical power carriers into a highly nonlinear fiber. The RF gain is defined as the difference between the electrical power photodetected using a FWM product and that from the conventional RoF system at the same optical power level. Experimental results demonstrate 24 dB gain after photodetection of the first FWM product. Furthermore, a performance analysis based on numerical simulations is reported in order to propose a high capacity intensity modulated radio over fiber architecture for future broadband access optical-wireless networks. Bit-error-rate curves of a 10 Gbit/s NRZ signal in different conditions of optical signal to noise ratio (OSNR) are presented for illustrating the applicability of the proposed photonics-based RF device. © 2015 IEEE.

关键词： Radio-over-fiber

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Performance comparison of a custom emulation-based test environment against a real-world LTE testbed 15

Performance comparison of a custom emulation-based test envi...

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2015 Workshop on NS-3, WNS3 2015

作者： Sakai, Sérgio Gambugge, Gilberto Takaki, Ricardo Seki, Jorge Bazzo, Juliano Miranda, João Paulo CPqD -Research and Development Center on Telecommunications R. Dr. Ricardo Benetton Martins s/n Campinas/SPCEP 13086-902 Brazil

ISBN: (纸本)9781450333757

Notwithstanding the value of Long Term Evolution (LTE) towards an improved user experience in next-generation networks, its associated high complexity is known to place computational and time burdens on testing tasks involving real-world platforms. Simulation is currently the tool most widely used to tackle this issue. LENA, for instance, is an open source simulator based on NS-3 that allows the design, evaluation, and validation of LTE networks. Despite of modeling the main LTE elements and interfaces, one limitation of LENA is that it docs not support the use of external traffic entities in conjunction with the simulation. In this paper, we describe how the NS-3 LENA LTE framework can be customized for use in an emulation-based test environment that allows a wider variety of real-world applications to be run over the simulated links. To validate our emulation results, we use as benchmark a testbed that differs from the aforementioned test environment in that the NS-3 server running the simulated network is replaced with a network made up of real-world platforms. Initial validation results, based on limited tests using an industry-standard VoIP test tool and iperf throughput tool, demonstrate that NS-3 LTE models can deliver voice quality and latency as good as an experimental testbed using actual LTE equipment over a range of signal-to-noise ratios. Similar conclusions arc also drawn for throughput, thus confirming the suitability of our emulation approach as a viable means to predict performance in real LTE networks. The good agreement of our experimental results is possible not only because the same functionality is implemented in both experiments but due to the use of the same traffic generation tools in the simulated and real-world LTE networks not possible in standard LENA simulation. © 2015 ACM.

关键词： Testbeds

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A DSL for configuration management of integrated network management system 17

A DSL for configuration management of integrated network man...

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17th International Conference on Enterprise Information Systems, ICEIS 2015

作者： Pieroni, Rosangela Penteado, Rosângela Aparecida Dellosso Department of Computing Federal University of São Carlos São Carlos SP13565-905 Brazil CPqD Research and Development Center In Telecommunications Campinas SP13086-902 Brazil

ISBN: (纸本)9789897580963

A management system of networks that takes all elements into consideration, regardless of the network technology, is one of the most emphasized requests by telecommunication companies. However, developing this system is not a trivial task. Furthermore, the software development process based on source code makes the task even more complex and requires a great effort of the developers to perform code update and maximize the reuse of software artifacts to insert a new network technology. In this paper, we propose a DSL approach to specify new network technologies into integrated network management system developed by a real company. An experiment was conducted according to all steps proposed by Wohlin (Wohlin et al., 2000) to validate our DSL approach versus specialization of classes with the purpose of increasing advantages with respect to time and number of errors inserted in the source code. Although the time spent to develop the application using the two approaches was not statistically different, all other results obtained such as code generated automatically without present errors and all comments reported by the participants regarding the ease of use of DSL, it encourages the development of new DSLs to others functions of the integrated network management system. Copyright © 2015 SCITEPRESS - Science and Technology Publications.

关键词： Software design

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Hierarchical taylor-made scheduling for data traffic with prioritization over LTE networks

Hierarchical taylor-made scheduling for data traffic with pr...

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International Workshop on telecommunications, IWT 2015

作者： Neto, Jahyr Goncalves Cardoso, Fabbryccio A. C. M. Ferreira, Paulo A. Valente Costa, Max H. M. University Center of Votuporanga Campinas SP Brazil Research and Development Center for Telecommunications - CPqD Campinas SP Brazil Department of Communications Department of Systems and Energy Campinas SP Brazil School of Electrical and Computer Engineering University of Campinas - Unicamp Campinas SP Brazil

ISBN: (纸本)9781467376228

Long Term Evolution (LTE) is the standard developed by the 3rd Generation Partnership Project (3GPP) to address the ITU's 4G requirements. For the first time, we have technology convergence in a generation of cellular communication systems. LTE promises data transmission of about 100 Mbps and its advanced version (LTE-A) goes even further with more than 1 Gbps in the downlink channel. Such very high data rates will only be achievable with appropriate network resource optimizations. Accordingly, this paper presents a flexible and adaptive scheme of multi-user scheduling considering data traffic prioritization in the LTE downlink channel. The proposed scheduling algorithm uses Proportional Fairness and Analytic Hierarchy Process (AHP) that allows to aggregate performance criteria and to improve resource allocation for users based on the general traffic. © 2015 IEEE.

关键词： Scheduling algorithms

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A Fiber Optic Powered Sensor Designed for Partial Discharges Monitoring on High Voltage Bushings

A Fiber Optic Powered Sensor Designed for Partial Discharges...

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SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference

作者： Joao B. Rosolem Elias K. Tomiyama Danilo C. Dini Fabio R. Bassan Rivael S. Penze Ariovaldo A. Leonardi Claudio Floridia Joao Paulo V. Fracarolli Romulo M. Teixeira CPqD - Research and Development Center in Telecommunications Cemig GT

ISBN: (纸本)9781467394932

In this work, we present the results of a fiber optic powered sensor for monitoring partial discharges on high voltage transformer bushings. The main advantages of the proposed system are high bandwidth, passivity, flexibility, non-intrusive, human and equipment risk free, easy installation and inherently galvanic isolation. The complete system is composed by the sensor that is one active hermetically sealed circular antenna installed near to the bushing flange, a fiber network and a control unit. The sensor is powered only by the optical power provided by one optic fiber connected to a remote optical source. At the same time, the partial discharge signals are transmitted by another optical fiber to the control unit installed in the substation room. We describe the design and the performance evaluation of the fiber optic powered antenna in laboratory.

关键词： Transformers Bushings Partial Discharges Antennas Optical fibers Power over Fiber PoF

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Design and Test of an ActiveFeedCircuit for Antenna Arrays with Reconfigurable Pattern

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Journal of Microwaves, Optoelectronics and Electromagnetic Applications 2015年 14卷 SI88-SI102页

作者： Ferreira, Daniel B. Bianchi, Ildefonso De Paula, Cristiano B. Microwaves and Optoelectronics Department - IEEM Technological Institute of Aeronautics São José dos CamposSP Brazil CPqD Research and Development Center in Telecommunications Wireless Systems Division - GSF Campinas - SP Brazil

In this paper, the design of an active feed circuit for antenna arrays with reconfigurable radiation pattern is presented. The adopted circuit topology is composed of phase shifters and variable gain amplifiers which enable the dynamic control of the amplitudes and phases of the array current excitations. The set of equations needed to configure the circuit components is derived and the measured patterns of an array fed by the proposed circuit are also shown in the paper, as well as the details for the fabrication of the circuit prototype. The excellent agreement between the theoretical and measured patterns validates both the design procedure and solutions adopted throughout the work. © 2015 SBMO/SBMag.

关键词： Timing circuits

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