XXXI Simpósio Brasileiro de Telecomunicações

This paper presents a method of speech enhancement performed in the time domain using a technique robust standard deviation. The technique was evaluated from three experiments, one using only the method and the other two as a proposal for post processing. The techniques used for the initial treatment applied to speech signals corrupted in the...

In this paper we study a class of codes for the transmission of a discrete-time continuous alphabet source over a Gaussian channel. Our proposal differs from the ones found in the literature, that mostly deal with one dimensional continuous sources, in the sense that the scheme proposed here encodes sources with k-dimensional support to be transmitted...

Transmission in high-frequency (HF) is an alternative to high range and low cost systems, as image transmission in surveillance systems. Due to the effects of this channel in the transmitted signals and its low bandwidth, it is necessary to both use techniques to protect the transmitted signal (equalization , error control coding, etc.) and signal...

Data compression will be extremely necessary in order to solve the problem of large data volume generated by smart meters. The aim of this work, is to investigate the source coding theory, which establishes the entropy as a fundamental limit on the performance of conventional data compression algorithms applied to daily load curve of a typical...

Motivado pela perspectiva de codificação de rede na camada fı́sica baseada em reticulados aninhados, este artigo considera comunicação em canais matriciais multiplicativos sobre anéis de cadeia finitos. Tais canais são descritos pela expressão Y = AX, em que X e Y são as matrizes de entrada e saı́da, respectivamente, e A é a matriz de transferência....

This work presents a graphical computational simulation tool to aid in the planning of cellular networks. The developed platform makes possible to determine the received power and the signal-to-interference ratio in any position of the analyzed region for different clusters, terrains and propagation models. This platform can be used to promote future...

Este trabalho apresenta um estudo de campo sobre a comparação entre as utilizações do protocolo IPv4 e do IP em pilha dupla no acesso a páginas web. Para realizar tal análise, desenvolveu-se um conjunto de ferramentas capazes de coletar informações sobre o conteúdo e o desempenho destas páginas. Os resultados, relativos a mais de 19.000 acessos aos...

Software defined radio (SDR) is an important tool for communication research nowadays. It allows for better spectrum utilization and leads to smarter communication systems. Besides, due to its flexibility, research groups have been using SDR hardware platforms for quicker implementation of new algorithms and development of products. Therefore, the...

This work deals with the nano-optical version of a Fabry-Perot cavity. By exciting plasmon modes on the metallic nanoparticles in the cavity, optical power can be squeezed into subwavelength scale without scattering effects stemmed from diffraction. As suggested by our first results, it surges feasible to use such structure as a building block for...

Mixed resolution stereoscopic video is a popular format aimed at 3D content consumption. Nevertheless, resolution differences among views can pose significant drawbacks if adapting such a format to other multiview functionalities, such as view synthesis. In this paper we adjust standard view synthesis methodology to mixed resolution conditions. Operating...