Results 11 to 20 of about 510 (175)

A zenith wet delay improved model in China based on GPT3 and random forest

Geodesy and Geodynamics
Zenith wet delay (ZWD) is a key parameter for the precise positioning of global navigation satellite systems (GNSS) and occupies a central role in meteorological research.
Shaoni Chen, Chunhua Jiang, Xiang Gao, Huizhong Zhu, Shuaimin Wang, Guangsheng Liu   +5 more
doaj   +2 more sources

Developing Iran's empirical zenith wet delay model (IR-ZWD) [PDF]

Journal of Atmospheric and Solar-Terrestrial Physics, 2023
The presence of water vapor in the lower atmosphere can introduce errors in satellite-based geodetic observations. Accurate modeling of this part of atmospheric delay is particularly challenging due to the considerable variations of water vapor. Therefore, constructing a reasonable model to predict Zenith Wet Delay (ZWD) can improve the accuracy of ...
Masoud Dehvari, Saeed Farzaneh, Ehsan Forootan   +2 more
openaire   +1 more source

Using GNSS Observations for Tropospheric Delay Prediction Using Artificial Intelligence [PDF]

Port Said Engineering Research Journal, 2023
GNSS technology holds significant importance across wide applications, ranging from mapping, surveying, and precise timekeeping to ship navigation. Its operational principle hinges on the accurate measurement of signal travel time, which is crucial for ...
Ahmed Sedeek
doaj   +1 more source

A Hybrid Deep Learning Algorithm for Tropospheric Zenith Wet Delay Modeling with the Spatiotemporal Variation Considered

Atmosphere
The tropospheric Zenith Wet Delay (ZWD) is one of the primary sources of error in Global Navigation Satellite Systems (GNSS). Precise ZWD modeling is essential for GNSS positioning and Precipitable Water Vapor (PWV) retrieval.
Yin Wu, Lu Huang, Wei Feng, Su Tian
doaj   +2 more sources

Impact of Tropospheric Mismodelling in GNSS Precise Point Positioning: A Simulation Study Utilizing Ray-Traced Tropospheric Delays from a High-Resolution NWM

Remote Sensing, 2021
In GNSS analysis, the tropospheric delay is parameterized by applying mapping functions (MFs), zenith delays, and tropospheric gradients. Thereby, the wet and hydrostatic MF are derived under the assumption of a spherically layered atmosphere.
Florian Zus, Kyriakos Balidakis, Galina Dick, Karina Wilgan, Jens Wickert   +4 more
doaj   +1 more source

An ERA5-Based Hourly Global Pressure and Temperature (HGPT) Model

Remote Sensing, 2020
The Global Navigation Satellite System (GNSS) meteorology contribution to the comprehension of the Earth’s atmosphere’s global and regional variations is essential.
Pedro Mateus, João Catalão, Virgílio B. Mendes, Giovanni Nico   +3 more
doaj   +1 more source

HGPT2: An ERA5-Based Global Model to Estimate Relative Humidity

Remote Sensing, 2021
The neutral atmospheric delay is one of the major error sources in Space Geodesy techniques such as Global Navigation Satellite Systems (GNSS), and its modeling for high accuracy applications can be challenging.
Pedro Mateus, Virgílio B. Mendes, Sandra M. Plecha   +2 more
doaj   +1 more source

Prediction of tropospheric wet delay by an artificial neural network model based on meteorological and GNSS data

Engineering Science and Technology, an International Journal, 2020
Estimation of tropospheric wet delay is of great importance for real-time weather forecasting applications. In the last decade, based on troposphere wet delays obtained from Global Navigation Satellite System observations, high temporal and spatial ...
Mahmut Oguz Selbesoglu
doaj   +1 more source

Tropospheric delay performance for GNSS integrated water vapor estimation by using GPT2w model, ECMWF's IFS operational model and in situ meteorological data [PDF]

Advances in Geosciences, 2018
Tropospheric delay comprises one of the most important error sources in satellite navigation and is caused when radio signals broadcasted by GPS satellites propagate into the atmosphere.
C. Oikonomou, F. Tymvios, F. Tymvios, C. Pikridas, S. Bitharis, K. Balidakis, S. Michaelides, H. Haralambous, H. Haralambous, D. Charalambous, D. Charalambous   +10 more
doaj   +1 more source

A New Method for Estimating Tropospheric Zenith Wet-Component Delay of GNSS Signals from Surface Meteorology Data

Remote Sensing, 2020
A new concept is proposed for estimating the zenith wet delay (ZWD) and atmospheric weighted average temperature by inputting the temperature, total pressure, and specific humidity from surface weather data.
Pengfei Xia, Jingchao Xia, Shirong Ye, Caijun Xu   +3 more
doaj   +1 more source