A Comparison of a GNSS‐GIM and the IRI‐2020 Model Over China Under Different Ionospheric Conditions
Abstract The ionosphere is a crucial factor affecting Global Navigation Satellite System positioning. The Global Ionosphere Map (GIM) or the International Reference Ionosphere (IRI) model can be used for regional ionospheric correction. Since southern China is located near the electron density equat...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2023-10-01
|
| Series: | Space Weather |
| Online Access: | https://doi.org/10.1029/2023SW003646 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1841536368441819136 |
|---|---|
| author | Rong He Min Li Qiang Zhang Qile Zhao |
| author_facet | Rong He Min Li Qiang Zhang Qile Zhao |
| author_sort | Rong He |
| collection | DOAJ |
| description | Abstract The ionosphere is a crucial factor affecting Global Navigation Satellite System positioning. The Global Ionosphere Map (GIM) or the International Reference Ionosphere (IRI) model can be used for regional ionospheric correction. Since southern China is located near the electron density equatorial anomaly, this study evaluates the performance of the Wuhan University GIM (WHU‐GIM) and the IRI‐2020 from 2008 to 2020 over the China region. The comparison indicates that the Total Electron Content (TEC) from IRI‐2020 is lower than that from WHU‐GIM overall, the discrepancy is more obvious in high solar conditions and low‐latitude regions. The differential Slant TEC (dSTEC) during a phase‐arc with about 0.1 TECU accuracy derived from Global Positioning System (GPS) observations is used for model validation, the results show that the accuracies of WHU‐GIM and IRI‐2020 are 3.14 and 4.57 TECU, respectively. The dSTEC error is larger at low latitudes and decreases with increasing latitude. GPS‐derived TEC is taken for reference to evaluate the model reliability. Results show that both models can reproduce the diurnal TEC variations, but IRI‐2020 is more influenced by geomagnetic activities. The TEC correction percentage for IRI‐2020 is about 60%–80% under different ionospheric conditions, while for WHU‐GIM is 80%–90%. The Single‐Frequency Precise Point Positioning is performed with the ionosphere delay corrected by the two models, respectively. The positioning errors show that using IRI‐2020 has a lower accuracy, and the TEC discrepancy of the IRI‐2020 can cause a large bias in the up direction, especially at low‐latitude regions. |
| format | Article |
| id | doaj-art-dfcb6d95db0e4725a88e76dfee51438b |
| institution | Kabale University |
| issn | 1542-7390 |
| language | English |
| publishDate | 2023-10-01 |
| publisher | Wiley |
| record_format | Article |
| series | Space Weather |
| spelling | doaj-art-dfcb6d95db0e4725a88e76dfee51438b2025-01-14T16:31:17ZengWileySpace Weather1542-73902023-10-012110n/an/a10.1029/2023SW003646A Comparison of a GNSS‐GIM and the IRI‐2020 Model Over China Under Different Ionospheric ConditionsRong He0Min Li1Qiang Zhang2Qile Zhao3GNSS Research Center Wuhan University Wuhan ChinaGNSS Research Center Wuhan University Wuhan ChinaGNSS Research Center Wuhan University Wuhan ChinaGNSS Research Center Wuhan University Wuhan ChinaAbstract The ionosphere is a crucial factor affecting Global Navigation Satellite System positioning. The Global Ionosphere Map (GIM) or the International Reference Ionosphere (IRI) model can be used for regional ionospheric correction. Since southern China is located near the electron density equatorial anomaly, this study evaluates the performance of the Wuhan University GIM (WHU‐GIM) and the IRI‐2020 from 2008 to 2020 over the China region. The comparison indicates that the Total Electron Content (TEC) from IRI‐2020 is lower than that from WHU‐GIM overall, the discrepancy is more obvious in high solar conditions and low‐latitude regions. The differential Slant TEC (dSTEC) during a phase‐arc with about 0.1 TECU accuracy derived from Global Positioning System (GPS) observations is used for model validation, the results show that the accuracies of WHU‐GIM and IRI‐2020 are 3.14 and 4.57 TECU, respectively. The dSTEC error is larger at low latitudes and decreases with increasing latitude. GPS‐derived TEC is taken for reference to evaluate the model reliability. Results show that both models can reproduce the diurnal TEC variations, but IRI‐2020 is more influenced by geomagnetic activities. The TEC correction percentage for IRI‐2020 is about 60%–80% under different ionospheric conditions, while for WHU‐GIM is 80%–90%. The Single‐Frequency Precise Point Positioning is performed with the ionosphere delay corrected by the two models, respectively. The positioning errors show that using IRI‐2020 has a lower accuracy, and the TEC discrepancy of the IRI‐2020 can cause a large bias in the up direction, especially at low‐latitude regions.https://doi.org/10.1029/2023SW003646 |
| spellingShingle | Rong He Min Li Qiang Zhang Qile Zhao A Comparison of a GNSS‐GIM and the IRI‐2020 Model Over China Under Different Ionospheric Conditions Space Weather |
| title | A Comparison of a GNSS‐GIM and the IRI‐2020 Model Over China Under Different Ionospheric Conditions |
| title_full | A Comparison of a GNSS‐GIM and the IRI‐2020 Model Over China Under Different Ionospheric Conditions |
| title_fullStr | A Comparison of a GNSS‐GIM and the IRI‐2020 Model Over China Under Different Ionospheric Conditions |
| title_full_unstemmed | A Comparison of a GNSS‐GIM and the IRI‐2020 Model Over China Under Different Ionospheric Conditions |
| title_short | A Comparison of a GNSS‐GIM and the IRI‐2020 Model Over China Under Different Ionospheric Conditions |
| title_sort | comparison of a gnss gim and the iri 2020 model over china under different ionospheric conditions |
| url | https://doi.org/10.1029/2023SW003646 |
| work_keys_str_mv | AT ronghe acomparisonofagnssgimandtheiri2020modeloverchinaunderdifferentionosphericconditions AT minli acomparisonofagnssgimandtheiri2020modeloverchinaunderdifferentionosphericconditions AT qiangzhang acomparisonofagnssgimandtheiri2020modeloverchinaunderdifferentionosphericconditions AT qilezhao acomparisonofagnssgimandtheiri2020modeloverchinaunderdifferentionosphericconditions AT ronghe comparisonofagnssgimandtheiri2020modeloverchinaunderdifferentionosphericconditions AT minli comparisonofagnssgimandtheiri2020modeloverchinaunderdifferentionosphericconditions AT qiangzhang comparisonofagnssgimandtheiri2020modeloverchinaunderdifferentionosphericconditions AT qilezhao comparisonofagnssgimandtheiri2020modeloverchinaunderdifferentionosphericconditions |