XXXV Simpósio Brasileiro de Telecomunicações e Processamento de Sinais

This paper proposes an implementation in Field Programmable Gate Array (FPGA) of a de-noising using Haar wavelet transform. For this a signal with noise was applied at a Haar level 5 Discrete Wavelet Transform (DWT) through an threshold and then through an Inverse Wavelet transfom (IDWT). The design procedure has been designed using the Electronic...

In this manuscript, the sinc exponential pulse (SEP) is evaluated at the transmitter and receiver side by using different metrics. The impulse response of the SEP is derived, analysed, and compared with the traditional RC pulse. The SEP is characterized by introducing two new design parameters, adding degrees of freedom to optimize the pulse for a...

This paper focuses on the steady-state analysis of a variable step-size normalized least-mean-square (VSS-NLMS) algorithm from the literature, which uses a step-size adjustment rule with high immunity against the measurement noise. Specifically, model expressions are derived aiming to predict the excess mean-square error (EMSE) as well as the mean...

This article presents the implementation of a dual band FSS for intelligent walls applications, covering the WiFi frequency bands, 2.4 GHz and 5.8 GHz. The four arms star geometry, associated to trapezoidal rings, are used, which allows a more flexible frequency response adjust. Initial project equations are introduced and the frequency...

The High Efficiency WLANs (HEW) Task Group (TG) has been developing since 2014 the IEEE 802.11ax amendment, the 6th generation of wireless local area networks (WLANs). One major novel feature of IEEE 802.11ax standard is the specification of uplink multi-user multiple-input multiple-output (UL MUMIMO) techniques to cope with the increase of UL...

This paper discusses the use of Vector Quantization (QV) and Discrete Cosine Transform (DCT) in image compression, in order to evaluate the performance of the combination of these techniques. Simulation results concerning the quantization of the DCT coefficients show that the joint use of the techniques leads, in average, to a smaller distortion...

This paper shows how spatial diversity affects multiuser system rate when a multilevel frequency shift keying modulation signal is transmitted over a fast Rayleigh fading channel with additive white Gaussian noise. No specific multiple access method is used. The channel’s short coherence time precludes the system from estimation or tracking channel...

This paper presents a probabilistic model to assess the interference produced by HAPS systems into FWA systems operating in the same frequency bands. To avoid some of the conservative assumptions considered in the traditional interference evaluation methods, in the proposed probabilistic approach the sidelobe antenna gains are characterized by...

This work deals with the behavioral modeling of power amplifiers for wireless communication systems based on complex-valued radial basis function neural network (CVRBFNN). In this work, modifications on the CVRBFNN input and output are proposed with the purpose of optimizing its usage for low-pass equivalent modeling. In comparison with a previous...

In this paper, the design of an aperture-coupled microstrip antenna to be installed onto a nano-satellite is described. The proposed antenna has been optimized to operate at 2.26 GHz (S-Band), which is the operating frequency of the downlink channel of the Brazilian System for Meteorological Data Acquisition. The electromagnetic analysis is done by...