Assessment of performance of the SHAO-C tropospheric delay correction model over low latitude and complex topography

Yohannes Getachew Ejigu, Gizaw Mengistu Tsidu

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Tropospheric signal delay can introduce a considerable error in satellite positioning if it is not properly modeled. In this work, the spatial and temporal variations of the zenith tropospheric delay (ZTD) over low latitude and complex topography of Ethiopia and Eritrea from the Greater Horn of Africa (GHA) region, are analyzed using ECMWF (European Center for Medium-Range Weather Forecast) pressure-level atmospheric data and compared with ZTD over 5-year period from 2007-2011 measured at several GPS stations of UNAVCO in the region. A new tropospheric delay correction model, SHAO-C used in China, is evaluated for its performance over the region with most GPS observational stations located in Ethiopia. The ZTD along altitude, latitude and longitude is fitted with a second order polynomials at a reference height, and the mean ZTD is modeled directly by a harmonic function together with an initial value and an amplitude in each grid. The coefficients of this model are generated using the ERA-Interim data at moderate resolution. The altitude is obtained from high resolution digital elevation model (DEM). The agreement between GPS and model ZTD is found to be very good which is reflected in overall average bias between -4.3 to -1.0 cm, and RMSE less than 4.5 cm. The results are within the requirements of most GNSS navigation or positioning applications in terms of the tropospheric delay correction.

Original languageEnglish
Title of host publicationProceedings of 2016 International Conference on Localization and GNSS, ICL-GNSS 2016
PublisherInstitute of Electrical and Electronics Engineers Inc.
ISBN (Electronic)9781509017577
DOIs
Publication statusPublished - Aug 4 2016
Event2016 International Conference on Localization and GNSS, ICL-GNSS 2016 - Barcelona, Spain
Duration: Jun 28 2016Jun 30 2016

Other

Other2016 International Conference on Localization and GNSS, ICL-GNSS 2016
CountrySpain
CityBarcelona
Period6/28/166/30/16

Fingerprint

Topography
Global positioning system
Harmonic functions
Model
Positioning
Navigation
Polynomials
Satellites
Longitude
Digital Elevation Model
Harmonic Functions
Weather
Forecast
China
High Resolution
Grid
Polynomial
Requirements
Coefficient
Range of data

All Science Journal Classification (ASJC) codes

  • Computer Networks and Communications
  • Control and Optimization
  • Signal Processing

Cite this

Ejigu, Y. G., & Tsidu, G. M. (2016). Assessment of performance of the SHAO-C tropospheric delay correction model over low latitude and complex topography. In Proceedings of 2016 International Conference on Localization and GNSS, ICL-GNSS 2016 [7533860] Institute of Electrical and Electronics Engineers Inc.. https://doi.org/10.1109/ICL-GNSS.2016.7533860
Ejigu, Yohannes Getachew ; Tsidu, Gizaw Mengistu. / Assessment of performance of the SHAO-C tropospheric delay correction model over low latitude and complex topography. Proceedings of 2016 International Conference on Localization and GNSS, ICL-GNSS 2016. Institute of Electrical and Electronics Engineers Inc., 2016.
@inproceedings{6733c3df426b4f6092cdce8405a0bfa5,
title = "Assessment of performance of the SHAO-C tropospheric delay correction model over low latitude and complex topography",
abstract = "Tropospheric signal delay can introduce a considerable error in satellite positioning if it is not properly modeled. In this work, the spatial and temporal variations of the zenith tropospheric delay (ZTD) over low latitude and complex topography of Ethiopia and Eritrea from the Greater Horn of Africa (GHA) region, are analyzed using ECMWF (European Center for Medium-Range Weather Forecast) pressure-level atmospheric data and compared with ZTD over 5-year period from 2007-2011 measured at several GPS stations of UNAVCO in the region. A new tropospheric delay correction model, SHAO-C used in China, is evaluated for its performance over the region with most GPS observational stations located in Ethiopia. The ZTD along altitude, latitude and longitude is fitted with a second order polynomials at a reference height, and the mean ZTD is modeled directly by a harmonic function together with an initial value and an amplitude in each grid. The coefficients of this model are generated using the ERA-Interim data at moderate resolution. The altitude is obtained from high resolution digital elevation model (DEM). The agreement between GPS and model ZTD is found to be very good which is reflected in overall average bias between -4.3 to -1.0 cm, and RMSE less than 4.5 cm. The results are within the requirements of most GNSS navigation or positioning applications in terms of the tropospheric delay correction.",
author = "Ejigu, {Yohannes Getachew} and Tsidu, {Gizaw Mengistu}",
year = "2016",
month = "8",
day = "4",
doi = "10.1109/ICL-GNSS.2016.7533860",
language = "English",
booktitle = "Proceedings of 2016 International Conference on Localization and GNSS, ICL-GNSS 2016",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
address = "United States",

}

Ejigu, YG & Tsidu, GM 2016, Assessment of performance of the SHAO-C tropospheric delay correction model over low latitude and complex topography. in Proceedings of 2016 International Conference on Localization and GNSS, ICL-GNSS 2016., 7533860, Institute of Electrical and Electronics Engineers Inc., 2016 International Conference on Localization and GNSS, ICL-GNSS 2016, Barcelona, Spain, 6/28/16. https://doi.org/10.1109/ICL-GNSS.2016.7533860

Assessment of performance of the SHAO-C tropospheric delay correction model over low latitude and complex topography. / Ejigu, Yohannes Getachew; Tsidu, Gizaw Mengistu.

Proceedings of 2016 International Conference on Localization and GNSS, ICL-GNSS 2016. Institute of Electrical and Electronics Engineers Inc., 2016. 7533860.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

TY - GEN

T1 - Assessment of performance of the SHAO-C tropospheric delay correction model over low latitude and complex topography

AU - Ejigu, Yohannes Getachew

AU - Tsidu, Gizaw Mengistu

PY - 2016/8/4

Y1 - 2016/8/4

N2 - Tropospheric signal delay can introduce a considerable error in satellite positioning if it is not properly modeled. In this work, the spatial and temporal variations of the zenith tropospheric delay (ZTD) over low latitude and complex topography of Ethiopia and Eritrea from the Greater Horn of Africa (GHA) region, are analyzed using ECMWF (European Center for Medium-Range Weather Forecast) pressure-level atmospheric data and compared with ZTD over 5-year period from 2007-2011 measured at several GPS stations of UNAVCO in the region. A new tropospheric delay correction model, SHAO-C used in China, is evaluated for its performance over the region with most GPS observational stations located in Ethiopia. The ZTD along altitude, latitude and longitude is fitted with a second order polynomials at a reference height, and the mean ZTD is modeled directly by a harmonic function together with an initial value and an amplitude in each grid. The coefficients of this model are generated using the ERA-Interim data at moderate resolution. The altitude is obtained from high resolution digital elevation model (DEM). The agreement between GPS and model ZTD is found to be very good which is reflected in overall average bias between -4.3 to -1.0 cm, and RMSE less than 4.5 cm. The results are within the requirements of most GNSS navigation or positioning applications in terms of the tropospheric delay correction.

AB - Tropospheric signal delay can introduce a considerable error in satellite positioning if it is not properly modeled. In this work, the spatial and temporal variations of the zenith tropospheric delay (ZTD) over low latitude and complex topography of Ethiopia and Eritrea from the Greater Horn of Africa (GHA) region, are analyzed using ECMWF (European Center for Medium-Range Weather Forecast) pressure-level atmospheric data and compared with ZTD over 5-year period from 2007-2011 measured at several GPS stations of UNAVCO in the region. A new tropospheric delay correction model, SHAO-C used in China, is evaluated for its performance over the region with most GPS observational stations located in Ethiopia. The ZTD along altitude, latitude and longitude is fitted with a second order polynomials at a reference height, and the mean ZTD is modeled directly by a harmonic function together with an initial value and an amplitude in each grid. The coefficients of this model are generated using the ERA-Interim data at moderate resolution. The altitude is obtained from high resolution digital elevation model (DEM). The agreement between GPS and model ZTD is found to be very good which is reflected in overall average bias between -4.3 to -1.0 cm, and RMSE less than 4.5 cm. The results are within the requirements of most GNSS navigation or positioning applications in terms of the tropospheric delay correction.

UR - http://www.scopus.com/inward/record.url?scp=84986232851&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84986232851&partnerID=8YFLogxK

U2 - 10.1109/ICL-GNSS.2016.7533860

DO - 10.1109/ICL-GNSS.2016.7533860

M3 - Conference contribution

AN - SCOPUS:84986232851

BT - Proceedings of 2016 International Conference on Localization and GNSS, ICL-GNSS 2016

PB - Institute of Electrical and Electronics Engineers Inc.

ER -

Ejigu YG, Tsidu GM. Assessment of performance of the SHAO-C tropospheric delay correction model over low latitude and complex topography. In Proceedings of 2016 International Conference on Localization and GNSS, ICL-GNSS 2016. Institute of Electrical and Electronics Engineers Inc. 2016. 7533860 https://doi.org/10.1109/ICL-GNSS.2016.7533860