18 Result(s)
within
Tianhe **ao
Atmospheric Sciences
Electrical Engineering
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Article
Design of real-time GNSS-R software-defined receiver for coastal altimetry using GPS/BDS/QZSS signals
Global navigation satellite system reflectometry (GNSS-R) has considerable potential for monitoring sea surface height with high spatiotemporal resolution at low cost. However, because of the immaturity of ref...
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Article
A precipitation forecast model with a neural network and improved GPT3 model for Japan
Accurate monitoring of atmospheric water vapor content is essential for the early warning of extreme weather events. As known, GNSS zenith troposphere delay (GNSS_ZTD) is an indispensable data source for retri...
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Article
Analysis of the J2 relativistic effect on the performance of on-board atomic clocks
The GNSS satellite atomic clock is subjected to appreciable relativistic effects during its in-orbit operation. These effects include drift due to the gravitational redshift and time dilation due to the relati...
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Article
Inter-system biases solution strategies in multi-GNSS kinematic precise point positioning
Estimating inter-system biases (ISBs) is important in multi-constellation Global Navigation Satellite System (GNSS) processing. The present study aims to evaluate and screen out an optimal estimation strategy ...
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Article
Effect of the polar cap ionospheric sporadic-E layer on GNSS-based positioning: a case study at Resolute Bay, Canada, September 5, 2012
We focus on the impacts of the polar cap ionospheric sporadic-E (Es) layer that occurred at Resolute Bay, Canada, on September 5, 2012, on the quality of the Global Positioning System (GPS) observable and the ...
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Article
LEO-constellation-augmented multi-GNSS real-time PPP for rapid re-convergence in harsh environments
GNSS signals are blocked in forests, urban canyons, and indoors. Precise positioning can hardly be guaranteed in these challenging environments. A low earth orbit (LEO) constellation serving as a navigation sy...
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Article
Integrated GNSS Doppler velocity determination for GEOHALO airborne gravimetry
A gravity sensor onboard an aircraft always measures the sum of all accelerations acting on the sensor. To separate the accelerations caused by the movement of the aircraft from the gravitational accelerations...
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Article
Multi-GNSS precise orbit positioning for airborne gravimetry over Antarctica
Accurate position, velocity, and acceleration information are critical for airborne gravimetry. In Antarctica, there is a sparse distribution of IGS stations, and the rough terrain makes it impractical to set ...
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Article
Comparing satellite orbit determination by batch processing and extended Kalman filtering using inter-satellite link measurements of the next-generation BeiDou satellites
The next-generation BeiDou satellites are equipped with inter-satellite link (ISL) payloads to realize the ability of autonomous navigation (Auto-Nav). We focus on the application of batch processing and exten...
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Article
Revisit the calibration errors on experimental slant total electron content (TEC) determined with GPS
The calibration errors on experimental slant total electron content (TEC) determined with global positioning system (GPS) observations is revisited. Instead of the analysis of the calibration errors on the car...
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Article
Robust adaptive filter for shipborne kinematic positioning and velocity determination during the Baltic Sea experiment
Information on trajectory and attitude is essential for analyzing gravimetric data collected on kinematic platforms. Usually, a Kalman filter is used to obtain high-accuracy positional and velocity information...
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Article
Image-aided platform orientation determination with a GNSS/low-cost IMU system using robust-adaptive Kalman filter
The availability of miniaturized sensors with enhanced capabilities, new methods for image processing, and easy access to small and low-weight airborne platforms for data acquisition, including unmanned vehicl...
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Article
Error analysis of the 3D similarity coordinate transformation
The 3D similarity coordinate transformation with the Gauss–Helmert error model is investigated. The first-order error analysis of an analytical least-squares solution to this problem is developed in detail. Wh...
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Article
Robust combination of IGS analysis center GLONASS clocks
The International GNSS Service (IGS) Analysis Centers (ACs) generate precise GNSS products by integrating tracking data from globally distributed IGS stations. The ACs’ products are further processed and combi...
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Article
GPS/BDS short-term ISB modelling and prediction
The Chinese BeiDou Navigation Satellite System (BDS) has completed its first milestone by providing coverage of the Asia–Pacific area navigation service since December 27, 2012. With the combination of BDS, th...
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Article
Improved method for estimating the inter-frequency satellite clock bias of triple-frequency GPS
Considering the contribution of the hardware biases to the estimated clock errors, an improved method for estimating the satellite inter-frequency clock bias (IFCB) is presented, i.e., the difference in the sa...
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Article
A new differential code bias (C1–P1) estimation method and its performance evaluation
The current satellite clock products are computed using the ionosphere-free phase (L1/L2) and code (P1/P2) observations. Thus, if users conduct undifferenced positioning using these clock products together wit...
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Article
GNSS navigation and positioning for the GEOHALO experiment in Italy
GEOHALO is a joint experiment of several German institutes for atmospheric research and earth observation where exploring airborne gravimetry over Italy using the High Altitude and LOng Range (HALO) aircraft ...
