XXXIII Simpósio Brasileiro de Telecomunicações

The present work aims to suggest a resource allocation approach to reduce computational complexity of bitloading techniques applied to power line communication (PLC) based on multicarrier modulation. This approach is based on grouping adjacent subcarriers and using the same resource allocation in this group, but it results in a datarate degradation....

This paper presents a general description of Rayleigh fading channel models for mobile com- munications. The channel models are analyzed and compared considering several statistical parameters.

The use of models described by the ratio of two polynomial approximations with memory has been rece iving particular attention by the wireless communication community. Rational models with memory require a lower number of coefficients and work better with extrapolation dat a than polynomial approximations. This work proposes a nov el...

The use of high-definition images has, as a rule, high cost while the use of lower resolution images and more affordable cost requires magnification. This paper presents a methodology that involves some math- ematical tools applied to the processing of images, with the objective of enlarging them to avoid the displacement or the deformation of the...

As restrições rigorosas de latência, custo e consumo de energia impostas pelo paradigma de comunicação Máquina a Máquina (M2M), requerem soluções que tentem otimizar ao máximo as características das redes sem fio. Um dos cenários de M2M mais empregados atualmente em cidades inteligentes e a Infraestrutura Avançada de Medição Inteligente (IAM) que...

To Know the usage of the communication circuits used by the Air Traffic Services can aid the development of a statistical network able to carry out the critical applications of these Services. In that way, this work deals with a set of stored communications between Air Traffic Controller and aircrafts to identify the dynamic of the channel’s usage....

In this paper, cosine transforms over fields of characteristic 2 (FFCT) are constructed. A fast algorithm for computing a specific FFCT is developed and an application of such transforms in digital image processing is described

The performance in terms of bit error rate for OFDM systems for short cyclic prefix and Doppler spread is obtained. In order to evaluate the effects of the short cyclic prefix and Doppler spread on system performance, expressions for the bit error rate are obtained through mathematical fitting to the results obtained by simulation. We have...

This paper presents the study of a microstrip antenna to be installed onto meteorological nano-satellit es. In order to increase the effective ground plane and to optimize the decoupling between the main and the cross polarizations, me tallic strips were attached to the antenna ground plane. The antenn a performance was evaluated using different...

Electrical Capacitance Tomography (ECT) is a technique developed to estimate phase distribution in pipelines. Most ECT instruments, however, suffer from high peripheral / low central sensitivities. This ill conditioning causes the recon- struction to be unstable, producing low quality images. This paper presents a new method for an ECT inspired...