XXXIII Simpósio Brasileiro de Telecomunicações

Many continuous wavelets are defined in the frequency domain and do not have analytical expressions in the time domain. Meyer wavelet is ordinarily defined in this way. In this note, we derive new straightforward analytical expressions for both the wavelet and scale function for the Meyer basis. The validity of these expressions is corroborated by...

The Internet of Things movement opens new possibilities for services and business along with new technological challenges, such as power efficiency, operation in constrained environments, security, and privacy. With the expectation of a high amount of devices connected in this Future Internet, scalability is also assumed to be a challenge. To address...

This article analyzes SDR technology implemented in multicarrier USRP systems using GnuRadio. The pace of technological development requires a constant evolution on the cellular devices, imposing to the user a constant replacement of the current mobile equipment. SDRs allow the simple recon- figuration of the mobile equipment software, easily...

A new test called rotation search is proposed for user identification and cryptographic key regeneration in systems employing a digital representation of the iris (iris code). When applied to the BIOSECURE, CASIA and NIST-ICE data bases the rotation search shows, on average, a two fold reduction in false rejection ratio (FRR) with a false...

A neutralidade da rede tem um significado diferente em diferentes países , sendo esta uma discussão importante, pois os prestadores de serviços, provedores de conteúdo e usu ários fina is precisam ter o mesmo entendimento com relação às funções e papeis uns dos outro s. A discussão não deveria ser conduzida de forma apenas bipolar,...

This work analyzes the influence of symbol detection error on cooperative in-home power line communication base d on channel estimates provided by a measurement campaign. We investigate cooperation communication based on a single relay model in which the relay node is situated in different locations between source and destination nodes by...

This paper discusses the project of capacitive cou- plers for Power Line Communications (PLC) in the range frequency of 9 kHz to 500 kHz and 1,7 to 500 MHz for low voltage networks. The use of Microstrip technique to design printed circuit boards and other relevant decisions in the p roject are proposed. The results based on these decisions...

This work seeks to reduce the bit error rate (BER) using LDPC codes (Low Den- sity Parity Check Code) as error correcting code. These codes are known since 1963 and they are based on the Robert Gallager’s research. Images may have vary modifications caused by instru- mental errors (sensors). The results show the degradation caused and error...

This work generalizes the chaotic map recently introduced by the authors with the addition of two new contro l parameters. The Lyapunov exponent is employed to analyze th e chaotic dynamics of the proposed map. The spectral characte ris- tics of chaotic signals generated by this map as a function of the control parameters are also investigated....

his paper presents the fabrication and experimental characterization of 7 printed microstrip antennas prototypes with rectangular pattern for application to the new fifth generation wireless communications technology (5G). These antennas are characterized according to a path loss test in an indoor environment at Fluminense Federal University...