XXX Simpósio Brasileiro de Telecomunicações

In this paper, we consider the uplink of a multiuser cooperative DS-CDMA communication system, where each user communicates with the base station with the help of R relays. A cooperative DS-CDMA configuration with direct-sequence spreading at the relays is proposed and for this cooperative scenario we formulate a new trilinear model for the...

This article presents an analysis of a Smart Grid network based on IEC 61850 standard and the data obtained through measurements of parameters from equipments used in such network. The main objective is to explore the operational limits of the network, i.e., determine the latency and congestion scenarios that affect the reliability of such network,...

CAC, Flow Control, Fuzzy Logic, Multi-Cclass Traffic

In this paper is proposed a comparative practice analysis between the Discrete Fourier Transform (DFT) and the Discrete Cosine Transform (DCT) in application of digital processing of speech signals. The analysis is based in to check which of two Transform is more efficient, as regard use of fewer samples of the spectrum for reconstruct a given...

Optical data extinction using ultra-long SOA is evaluated up to 56 Gb/s. The analysis of the deleterious effects such as spectral broadening and imperfect erasing predicts useful carrier wavelength reuse up to 20 Gb/s.

IPTV is a technology that has been developed over the last years and is gaining recognition worldwide as a viable alternative to offer audiovisual contents by telecommunications operators. IMS architecture is a framework developed to deliver IP-based multimedia services and the key to fixed-mobile convergence of next generation networks. This work...

We have seen in [13] a new reduction method for the decoding of 2×2 algebraic space-time codes, called algebraic reduction as been introduced. Algebraic codes such that the volume of the Dirichlet’s polyhedron of its units group is small are better suited for decoding using the method of algebraic reduction. In this paper, we propose a new framework...

This article presents a design in digital hardware for transcendental function computation (magnitude and phase of a complex number) using vector coordinates in the CORDIC algorithm in vectoring mode. The code was synthesized for FPGA using Xilinx development tools for the Spartan-3E xc3s500e family. Besides, performance analysis is realized...

This paper presents a comparative study among distinct classes of interleavers, applied to non-uniquely decodable convolutional code pairs, over a two-user binary adder channel (2-BAC), in the presence of additive white Gaussian noise. Performance curves are presented with results of computer simulations, when using convolutional encoders for each...

A short review on the current status of the deployment of optical access networks for several regions is presented. The concept of hybrid (optical-wireless) access networks, focusing on the physical transport of RF signals over optical fibers is introduced. Numerical results obtained through simulations for the physical layer of optical access...