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Constelações ciclotômicas
(Universidade Estadual Paulista (Unesp), 2006-02-17)
O principal objetivo do presente trabalho foi o estudo da construção de constelações de sinais casadas a grupos quocientes aditivos, via corpos quadráticos e corpos ciclotômicos. E por meio dessas constelações de sinais, ...
Multivariate analysis of combined GPS/GLONASS point positioning performance in Brazilian regions under different ionospheric conditions
(2019-06-01)
The development of Global Navigation Satellite Systems (GNSS) was a revolution in activities related to positioning. Currently, GLONASS (Global'naya Navigatsionnaya Sputnikovaya Sistema) and GPS (Global Positioning System) ...
Modulation Optimization for Achieving Energy Efficient Communications over Fading Channels
(IEEE, 2012)
It is commonly assumed that the energy consumption of wireless communications is minimized when low-order modulations such as BPSK are used. Nevertheless, the literature provides some evidence that low-order modulations ...
Desconvolução autodidata concorrente para beamformers não supervisionados em antenas controladas por reatância
(Pontifícia Universidade Católica do Rio Grande do SulPorto Alegre, 2007)
A ESPAR (Electronically Steerable Parasitic Array Radiator) é uma antena adaptativa, utilizada para recepção de sinais digitais. Esta antena, diferentemente das demais antenas inteligentes, necessita de apenas um downconverter ...
Desconvolução autodidata concorrente para beamformers não supervisionados em antenas controladas por reatância
(Pontifícia Universidade Católica do Rio Grande do SulPorto Alegre, 2007)
A ESPAR (Electronically Steerable Parasitic Array Radiator) é uma antena adaptativa, utilizada para recepção de sinais digitais. Esta antena, diferentemente das demais antenas inteligentes, necessita de apenas um downconverter ...
Stochastic stability analysis for the constant-modulus algorithm
(IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2008)
We derive an easy-to-compute approximate bound for the range of step-sizes for which the constant-modulus algorithm (CMA) will remain stable if initialized close to a minimum of the CM cost function. Our model highlights ...
Orbit determination using GPS including perturbations due to geopotential coefficients of high degree and order and solar radiation pressure
(Univelt Inc, 2008-01-01)
The main target here is to determine the orbit of an artificial satellite, using signals of the GPS constellation and least squares algorithms implemented through sequential Givens rotations as a method of estimation, with ...
Orbit determination using GPS including perturbations due to geopotential coefficients of high degree and order and solar radiation pressure
(Univelt Inc, 2008-01-01)
The main target here is to determine the orbit of an artificial satellite, using signals of the GPS constellation and least squares algorithms implemented through sequential Givens rotations as a method of estimation, with ...
Orbit determination using gps including perturbations due to geopotential coefficients of high degree and order and solar radiation pressure
(2008-12-01)
The main target here is to determine the orbit of an artificial satellite, using signals of the GPS constellation and least squares algorithms implemented through sequential Givens rotations as a method of estimation, with ...