Results 161 to 170 of about 1,619 (201)

Improved Mapping of Tropospheric Delays

Journal of Atmospheric and Oceanic Technology, 2001
Abstract The authors compare several methods to map the a priori tropospheric delay of global positioning system (GPS) signals from the zenith direction to lower elevations. This is commonly achieved with so-called mapping functions. Dry mapping functions are applied to the hydrostatic delay; wet mapping functions are used to map the zenith wet delay ...
Christian Rocken, Sergey Sokolovskiy, James M. Johnson, Doug Hunt   +3 more
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Strategies for estimating tropospheric delays with GPS

2002 IEEE Position Location and Navigation Symposium (IEEE Cat. No.02CH37284), 2003
Until recently, the tropospheric zenith delay (TZD) was considered a nuisance parameter of the GPS observation model. However, as the requirements of the weather forecasting community have become better understood, the possible use of TZDs in weather forecasting has been recognized.
P. Collins, Y. Mireault, P. Heroux
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Refined Tropospheric Delay Models for CONT11

2015
For the period of CONT11, a continuous VLBI campaign which lasted from September 15 through September 29, 2011, new a coefficients for the Vienna Mapping Functions 1 (VMF1; Bohm et al., J Geophys Res 111:B02406, 2006) and an extended calculation strategy for horizontal gradients were applied.
D. Landskron, A. Hofmeister, J. Böhm
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4D tropospheric tomography using GPS estimated delays

IEEE 1999 International Geoscience and Remote Sensing Symposium. IGARSS'99 (Cat. No.99CH36293), 2003
Retrieval of 4D fields of the tropospheric distribution of water vapor using GPS measurements is an additional and attractive use of the Global Positioning System. Stochastic GPS tomography has successfully been used in ionospheric studies and the authors describe a similar approach for tropospheric studies.
A. Flores, G. Ruffini, A. Rius
openaire   +1 more source

Tropospheric delay models for GNSS in Indonesia

2021
Tropospheric delay is one of the major error sources in space geodetic observations, including GNSS. It is important to treat these delays accordingly to improve the accuracy of the observations. The tropospheric delay models VMF1 and GMF are widely used in GNSS data analysis. Recently, a new and refined version of VMF1, VMF3 was released.
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Tropospheric Delay from VLBI and GNSS Measurements

Astronomy Letters, 2018
Using an updated version of the QUASAR software package developed at the Institute of Applied Astronomy of the Russian Academy of Sciences, we have processed the VLBI observations within the international CONT14 program (May 6–20, 2014), in which a global network of 17 stations was involved (a total of ~250 000 observations).
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Estimation of tropospheric time delay for Indian LAAS

2013 International Conference on Emerging Trends in VLSI, Embedded System, Nano Electronics and Telecommunication System (ICEVENT), 2013
In LAAS with airport pseudolites (APLs), error introduced in the signals due to tropospheric time delay proves to be the largest in pseudolite error budget. In this paper, tropospheric delay (TD) is estimated using Hopfield model and RTCA model for a typical LAAS scenario. Hopfield model is used to estimate delay in GPS signal and RTCA model is used to
Q. Sultana, A. D. Sarma, M. Q. Javeed
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Evaluation of Different Tropospheric Delay Models

2008
Tropospheric delay can be a signifi cant source of error in satellite-based positioning systems. Two basic types of delay prediction models exist, the first using surface meteorological parameters to estimate the magnitude of the tropospheric delay, and the other global models using average and seasonal variation data.
Kos, Tomislav, Markežić, Ivan, Botinčan, Maja   +2 more
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Estimation of Tropospheric Delay Models Compliance

2008
Tropospheric delay can be a significant source of error for satellite-based positioning systems, if it is not properly estimated. Two basic types of delay prediction models exist. The first use surface meteorological parameters to estimate the magnitude of the tropospheric delay, and the other global models use average and seasonal variation data.
Kos, Tomislav, Botinčan, Maja, Markežić, Ivan   +2 more
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An Tropospheric Delay Model for GPS NET RTK

2010 Second International Conference on Information Technology and Computer Science, 2010
The network-based GPS technique provides a broad Spectrum of corrections for real-time kinematic. And the atmospheric refraction error is the main factors to be sufficient to support the ambiguity resolution (AR) and accuracy of the long-distance RTK.
Qiu Lei, Li Lei, Wang Zemin
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