XXXVIII Simpósio Brasileiro de Telecomunicações e Processamento de Sinais

This paper presents the design of an RF front end for a base transceiver station implemented with a commercial general purpose software defined radio board. This front end helps to decrease the total cost of deploying community networks and the contribution of this paper is to disclose its project and simulation results, as well as discuss the aspects...

Ultra-Reliable Low-Latency Communication (URLLC), contemplated in the Fifth-Generation New Radio (5G NR) standard, is considered essential to a broader implementation of latency-sensitive future technologies. Grant-Free (GF) schemes have been proposed towards reducing latency in URLLC, but the increased probability of collision conflicts with the...

A criptografia caótica é uma maneira eficiente de criptografar textos, porque utiliza recursos de embaralhamento intrínsecos do atrator. Neste trabalho, é apresentado um algoritmo gerador de números pseudo-aleatórios utilizando o mapa logístico. Sua estrutura é baseada no protocolo de Baptista, e utiliza partições da medida natural associadas a...

Automatic detection of parking lot spaces is essential for the management of large buildings. Knowing the availability of vacancies helps to reduce queues and harmful gas emissions, improve scalability, and save time to find parking space. However, vehicle detection in aerial images presents many challenges, such as the reduced scale of the images and...

In this work, we analyze the adversarial network proposed by Brakel and Bengio at [5] to solve the problem of independent component analysis (ICA). Guided by a discriminator of independence, a linear autoencoder learns to codify a set of samples into estimates of their independent components. This is achieved by training the autoencoder to "fool the...

Multiple criteria decision analysis aims at ranking alternatives by means of multiple criteria. In general, the data classically used are the data in only the instant of time in which the decision is made. However, these data are not representative when the consequences of the choice depend on the future data of the criteria. Thus, we propose to predict...

In this paper, we study a buffer-state-based relay selection scheme in a underlay cognitive radio (CR) non-orthogonal multiple access (NOMA) network limited by the interference limit accepted by the primary. To model the state of the relays in relation to packet numbers, it was necessary to implement the Markov chain model. The results of the simulations...

This work introduces the concepts of self-similar matrix and quasi self-similar matrix, as well as a metric between a quasi self-similar matrix and a self-similar matrix of its class. A systematic method for converting a quasi self-similar matrix into a self-similar matrix and possible adjustment factors is presented. A method of expanding an arbitrary...

Adaptive filtering algorithms are flexible mechanisms that adapt themselves to the environment statistics in which they are immersed. It is known that in practice several transfer functions are sparse, in the sense that their energy is concentrated in a few (sometimes clustered) coefficients. In this paper, a new normalized adaptive algorithm tailored to...

This work proposes a fast algorithm for computing a product of two quaternions. The direct computation of this product requires 16 multiplications and 12 additions. The algorithm proposed here uses 8 multiplications and 28 additions, thus reducing the multiplicative complexity for computing the quaternion product.