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Dynamical and magnetic field time constants for Titan's ionosphere: Empirical estimates and comparisons with Venus
(American Geophysical Union, 2010-10)
Plasma in Titan´s ionosphere flows in response to forcing from thermal pressure gradients, magnetic forces, gravity, and ion-neutral collisions. This paper takes an empirical approach to the ionospheric dynamics by using ...
Tackling ionospheric scintillation threat to GNSS in Latin America
(Edp Sciences S A, 2011-01-01)
Scintillations are rapid fluctuations in the phase and amplitude of transionospheric radio signals which are caused by small-scale plasma density irregularities in the ionosphere. In the case of the Global Navigation ...
Correcão ionosférica utilizando os MAPAS: Globais do TEC DO IGS: Avaliação no posicionamento por ponto na região brasileira
(2007-07-01)
One of the main drawbacks of the GPS accuracy for L1 users is the error due to ionosphere. This error depends on the total electron content presents in the ionosphere, as well as of the carrier frequency. Some models have ...
Electron density and temperature measurements in the cold plasma environment of Titan: Implications for atmospheric escape
(American Geophysical Union, 2010-10)
We present electron temperature and density measurements of Titan's cold ionospheric plasma from the Langmuir probe instrument on Cassini from 52 flybys. An expression of the density as a function of temperature is presented ...
Ionospheric tomography using GNSS: multiplicative algebraic reconstruction technique applied to the area of Brazil
(2016-10-01)
Experimental analysis was performed using multiplicative algebraic reconstruction technique (MART) to map the ionosphere over Brazil. Code and phase observations from the global navigation satellite system (GNSS) together ...
Estimativa e análise de índices de irregularidades da ionosfera utilizando dados GPS de redes ativas
(2013-09-19)
Observable GNSS (Global Navigation Satellite System) are affected by systematic errors due to free electrons present in the ionosphere. The error associated with the ionosphere depends on the Total Electron Content (TEC), ...
Extended ionospheric amplitude scintillation model for GPS receivers
(Amer Geophysical Union, 2014-05-01)
Ionospheric scintillation is a phenomenon that occurs after sunset, especially in the low-latitude region, affecting radio signals that propagate through the ionosphere. Depending on geophysical conditions, ionospheric ...
Brazilian active GNSS networks as systems for monitoring the ionosphere
(2017-07-01)
This research shows the viability of using Global Navigation Satellite System (GNSS) stations from Brazilian active networks in monitoring the ionosphere. Various indexes of ionospheric irregularities and scintillation of ...
Programa científico para o monitoramento em tempo real ou pós-processado das irregularidades ionosféricas e cintilação dos sinais GNSS
(2016-01-01)
Brazil is one of the countries that suffer more the effects of the ionosphere, especially those from the Equatorial Ionization Anomaly, ionospheric irregularities and scintillation of GNSS (Global Navigation Satellite ...
Acurácia do posicionamento absoluto GPS com correção da ionosfera advinda de mapas ionosféricos globais e regionais
(2015-01-01)
The effect caused by the ionosphere in the GPS signal is one of the most important in the geodetic coordinate estimation process, mainly for data collected by single frequency receivers, if a not consistent ionospheric ...