| Full text | |
| Author(s): |
de Oliveira, Cesar Buchile Abud
[1]
;
Espejo, Teddy Modesto Surco
[2]
;
Moraes, Alison
[3]
;
Costa, Emanoel
[2]
;
Sousasantos, Jonas
[1]
;
Lourenco, Luis Felipe Dias
[4]
;
Abdu, Mangalathayil Ali
[5]
Total Authors: 7
|
| Affiliation: | [1] ITA, Praca Marechal Eduardo Gomes 50, BR-12228900 Sao Jose Dos Campos, SP - Brazil
[2] Pontificia Univ Catolica Rio de Janeiro PUC Rio, Ctr Estudos Telecomunicacoes CETUC, Rua Marques Sao Vicente 225, BR-22451900 Rio De Janeiro, RJ - Brazil
[3] IAE, Praca Marechal Eduardo Gomes 50, BR-12228904 Sao Jose Dos Campos, SP - Brazil
[4] EMBRAER, Rod Presidente Dutra, KM 134, BR-12247004 Sao Jose Dos Campos, SP - Brazil
[5] INPE, Ave Astronautas 1-758, BR-1222701 Sao Jose Dos Campos, SP - Brazil
Total Affiliations: 5
|
| Document type: | Review article |
| Source: | SURVEYS IN GEOPHYSICS; v. 41, n. 4 MAR 2020. |
| Web of Science Citations: | 0 |
| Abstract | |
The ionosphere over the Brazilian region has particular characteristics due to the large geomagnetic declination angle over most of the territory. Furthermore, the equatorial ionization anomaly southern crest is located over the Brazilian territory. In this region, plasma irregularities may arise in the post-sunset hours. These ionospheric irregularities develop in the form of magnetic field-aligned plasma depletions, known as equatorial plasma bubbles, which may seriously affect radio signals that propagate through them. These irregularity structures can cause amplitude and phase scintillation of the propagating signals, thereby compromising the availability, performance, and integrity of satellite-based communication and navigation systems. Additionally, the total electron content (TEC) introduces propagation delays that can contribute to range measurement errors for global positioning system (GPS) users. The ionospheric characteristics change significantly according to the time of day, season, as well as the solar and geomagnetic activities, among other factors. Indeed, the ionosphere is one of the most significant sources of errors in the positioning and navigation systems based on the GPS satellites. Due to these features, there is a strong interest by the scientific community in better understanding and characterizing the ionospheric behavior. In this context, the TEC analysis has wide applicability for space plasma studies and is a well-established tool for investigating the ionospheric behavior and its potential impact on space-based navigation systems. One of the goals of these studies is the generation of TEC maps for a geographic region based on GPS observations. In the present work, some electrodynamic processes of the low-latitude ionosphere are reviewed and the TEC estimation based on GPS measurements is revisited in detail. A methodology aimed at creating the TEC maps is presented and validated by comparison with results from other geophysical instruments, such as all-sky imagers and ionosondes. Finally, examples of the ionospheric behavior displayed by TEC maps during equatorial plasma bubble events and a geomagnetic storm are fully described and discussed. (AU) | |
| FAPESP's process: | 17/50115-0 - GNSS technology for supporting air navigation |
| Grantee: | Joao Francisco Galera Monico |
| Support Opportunities: | Research Grants - Research in Public Policies |
| FAPESP's process: | 06/04008-2 - GNSS: investigations and applications in geodetic positioning, in studies related to the atmosphere and precision agriculture |
| Grantee: | Joao Francisco Galera Monico |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 18/06158-9 - Statistical Studies of the Variation of Ionospheric Parameters and Their Relationship with Space Weather Events |
| Grantee: | Jonas de Sousa dos Santos |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |