Results 31 to 40 of about 424 (165)

Performance assessment of radio occultation data from GeoOptics by comparing with COSMIC data

Earth, Planets and Space, 2022
Responding to the ever-growing demand for environmental information, the National Oceanic and Atmospheric Administration (NOAA) seeks to enter into contracts to purchase Global Navigation Satellite System (GNSS) radio occultation (RO) observations ...
Hyeyeon Chang, Jiyun Lee, Hyosang Yoon, Y. Jade Morton, Alex Saltman   +4 more
doaj   +1 more source

Effect of GNSS RO on prediction of the 2021 Henan Rainstorm

, 2022
Abstract Precise prediction of the extremely heavy rainstorm is still challenging due to less or low spatial-temporal measurements. Nowadays, space-borne Global Navigation Satellite System (GNSS) radio occultation (RO) provides high spatial-resolution atmospheric parameters, which may improve the prediction precision of heavy rainfalls. In this
Yu Wang, Shuanggen Jin
openaire   +1 more source

A Machine Learning-Based Method for Wind Fields Forecasting Utilizing GNSS Radio Occultation Data

IEEE Access, 2022
With the development of computer technology and expanding environmental issues, machine learning has received more and more attention in the field of weather forecasting.
Xuezhao Chu, Weihua Bai, Yueqiang Sun, Wei Li, Congliang Liu, Hongqing Song   +5 more
doaj   +1 more source

Evaluation of Geometric and Atmospheric Doppler for GNSS-RO Payloads

AUT Journal of Electrical Engineering, 2016
To reduce the sampling rate in global navigation satellite system (GNSS)-radio occultation receivers, it is essential to establish a suitable estimation of Doppler frequency from the received signal in the satellite onboard receiver. This receiver is usually located on low earth orbit satellite and receives GNSS satellites signal in the occultation ...
L. Mohammadi, S. Amiri, G.R. Mohammadkhani   +2 more
openaire   +2 more sources

Supervised Detection of Ionospheric Scintillation in Low-Latitude Radio Occultation Measurements

Remote Sensing, 2021
Global Navigation Satellite System (GNSS) Radio Occultation (RO) has provided high-quality atmospheric data assimilated in Numerical Weather Prediction (NWP) models and climatology studies for more than 20 years.
Vinícius Ludwig-Barbosa, Thomas Sievert, Anders Carlström, Mats I. Pettersson, Viet T. Vu, Joel Rasch   +5 more
doaj   +1 more source

Review of Assimilating Spaceborne Global Navigation Satellite System Remote Sensing Data for Tropical Cyclone Forecasting

Remote Sensing
Global Navigation Satellite System (GNSS) Radio Occultation (RO) and GNSS Reflectometry (GNSS-R) are the two major spaceborne GNSS remote sensing (GNSS-RS) techniques, providing observations of atmospheric profiles and the Earth’s surface. With the rapid
Weihua Bai, Guanyi Wang, Feixiong Huang, Yueqiang Sun, Qifei Du, Junming Xia, Xianyi Wang, Xiangguang Meng, Peng Hu, Cong Yin, Guangyuan Tan, Ruhan Wu   +11 more
doaj   +1 more source

Stratospheric gravity waves in a post-limb sounder era: can GNSS-RO be used to extend the SABER QBO-driving record? [PDF]

Atmospheric Measurement Techniques
The quasi-biennial oscillation (QBO) is a slowly repeating cycle of winds which dominates tropical lower-stratospheric dynamics and has been described as the “heartbeat of the stratosphere”. However, it is challenging to represent in weather and climate
M. Almowafy, M. Almowafy, C. J. Wright, N. P. Hindley   +3 more
doaj   +1 more source

Correcting negatively biased refractivity below ducts in GNSS radio occultation: an optimal estimation approach towards improving planetary boundary layer (PBL) characterization [PDF]

Atmospheric Measurement Techniques, 2017
Global Navigation Satellite System (GNSS) radio occultation (RO) measurements are promising in sensing the vertical structure of the Earth's planetary boundary layer (PBL).
K.-N. Wang, M. de la Torre Juárez, C. O. Ao, F. Xie   +3 more
doaj   +1 more source

Assessment of GRAS Ionospheric Measurements for Ionospheric Model Assimilation

Remote Sensing, 2023
We conducted a study to assess the GNSS (Global Navigation Satellite System) Receiver for Atmospheric Sounding (GRAS) ionospheric data quality by processing Radio Occultation (RO) observations of ionospheric products.
M. M. Hoque, F. S. Prol, M. Hernandez-Pajares, R. Notarpietro, L. Yuan, G. Olivares-Pulido, V. Graffigna, A. Von Engeln, C. Marquardt   +8 more
doaj   +1 more source

Artificial Intelligence in Autonomous Mobile Robot Navigation: From Classical Approaches to Intelligent Adaptation

Advanced Intelligent Systems, EarlyView.
Artificial intelligence (AI) is reshaping autonomous mobile robot navigation beyond classical pipelines. This review analyzes how AI techniques are integrated into core navigation tasks, including path planning and control, localization and mapping, perception, and context‐aware decision‐making. Learning‐based, probabilistic, and soft‐computing methods
Giovanna Guaragnella, Angelo Cardellicchio, Cosimo Patruno, Massimiliano Nitti, Nicola Pedrocchi, Vito Renò   +5 more
wiley   +1 more source