XXXV Simpósio Brasileiro de Telecomunicações e Processamento de Sinais

O presente estudo aborda o processo da quantização estocástica utilizando o fenômeno conhecido como ressonância estocástica. Neste trabalho foram realizadas simulações da quantização estocástica aplicada a imagens de um banco de dados. Verifica-se que o sistema possui melhor desempenho para uma SNR de entrada intermediária, corroborando o...

The fourth generation of mobile communications provides many benefits such as high transmit data rates, low transmit power consumption and reduced latency. Cooperative communication consists in a key concept to those systems that allows the achievement of gains in transmit data rates and reliability. The potential of cooperative communications can...

In the present paper, a semi-blind receiver for a multiuser uplink DS-CDMA (Direct-Sequence Code-Division Multiple-Access) system based on relay aided cooperative com- munications is proposed. For the received signal, a quadrilinear Parallel Factor (PARAFAC) tensor decomposition is adopted, such that the proposed receiver can semi-blindly estimate...

State-of-the-art automatic speech recognition (ASR) systems are comprised of complex decoders that have a large number of parameters that allow tuning for performance and speed. These parameters are often optimized manually, based on past experience and specialist knowledge. Specically, to reach optimal performance, deep understanding of each...

The massive amount of low-end uplink traffic of Machine to Machine (M2M) communications are a key aspect of what 5G will be. In this context, Narrowband-IoT (NB-IoT) is described as the next step to allow Long Term Evolution (LTE) support for this type of traffic. This new technology provides support to massive amounts of ultra-low-end...

Phased array systems employ a set of properly cho- sen radiating elements, geometrically configured and strategically excited in order to render a specific radiation pattern, best suited for a given application. When the total antenna size emerges as an application constraint, both size of the radiating elements as well as the distance between them...

The goal of the paper is to increase the response of a miniaturized circularly polarized microfiber antenna, which has been used in previous works to validate a technique for obtaining electromagnetic polarization using an adaptation of the linear component method. Parameters were changed as the type of conductor used, substrate and position of the...

This article presents a study on the implications of different audio codecs on perceptual voice analysis. A VoIP- based transmission scenario was created, using Asterisk and the Microsip softphone, to aid in the diagnosis of distance vocal deviations. Each selected signal was submitted to four transmissions, using a specific codec. Using the EAV...

A popularização dos smartphones levou a um crescimento acentuado do tráfego de vídeo streaming em redes moveis, que já e a principal aplicação da rede em termos de tráfego. O vídeo streaming demanda recursos de qualidade de servic¸o (QoS, quality of service) para seu correto funcionamento. Em sistemas Long-term Evolution (LTE) a qualidade de...

In this paper, we improve the performance of packet scheduling in LTE system for multimedia service applications us- ing traffic policing algorithms known as leaky bucket controllers. We achieve fairness between classes of service, the arrival rates of packets to transmission queues of the scheduler. Simulation results show that schedulers with...