Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Estimating the Time Tag Bias of HY-2A Radar Altimeter and Its Application to Dual-frequency Ionosphere Correction
The sea surface height (SSH) derived from radar altimetry is determined by the distance from the satellite to the sea surface and the altitude of the satellite above a reference ellipsoid. The former is measured by the radar altimeter, while the latter is determined by the precision orbit determination (POD). The clock for the POD equipment is independent from that of the radar altimeter onboard the HY-2A satellite. The time tag bias, which is the bias between the time tags provided by the two independent clocks, can greatly affect the SSH measurement accuracy of HY-2A altimeter. This paper estimates the time tag bias of HY-2A radar altimeter using the crossover differences obtained from the sensor geophysical dataset records (SGDR) from February 2014. We obtained a −0.61-ms Ku-band time tag bias and a −5.61-ms C-band time tag bias. After we added the time tag bias corrections to the SSH measurements from Ku and C bands, respectively, the means and standard deviations of the global crossover differences can be significantly reduced. We then applied the SSH measurements with the time tag biases corrected to calculate the HY-2A dual-frequency ionosphere correction, significantly improving the accuracy of the HY-2A dual-frequency ionosphere correction.
Estimating the Time Tag Bias of HY-2A Radar Altimeter and Its Application to Dual-frequency Ionosphere Correction
The sea surface height (SSH) derived from radar altimetry is determined by the distance from the satellite to the sea surface and the altitude of the satellite above a reference ellipsoid. The former is measured by the radar altimeter, while the latter is determined by the precision orbit determination (POD). The clock for the POD equipment is independent from that of the radar altimeter onboard the HY-2A satellite. The time tag bias, which is the bias between the time tags provided by the two independent clocks, can greatly affect the SSH measurement accuracy of HY-2A altimeter. This paper estimates the time tag bias of HY-2A radar altimeter using the crossover differences obtained from the sensor geophysical dataset records (SGDR) from February 2014. We obtained a −0.61-ms Ku-band time tag bias and a −5.61-ms C-band time tag bias. After we added the time tag bias corrections to the SSH measurements from Ku and C bands, respectively, the means and standard deviations of the global crossover differences can be significantly reduced. We then applied the SSH measurements with the time tag biases corrected to calculate the HY-2A dual-frequency ionosphere correction, significantly improving the accuracy of the HY-2A dual-frequency ionosphere correction.
Estimating the Time Tag Bias of HY-2A Radar Altimeter and Its Application to Dual-frequency Ionosphere Correction
Jiang, Maofei (Autor:in) / Xu, Ke / Liu, Yalong / Wang, Lei
Marine geodesy ; 40
2017
Aufsatz (Zeitschrift)
Englisch
Correction of Single Frequency Altimeter Measurements for Ionosphere Delay
| Online Contents | 1997
ENVISAT Radar Altimeter Tracker Bias
| Online Contents | 2006
Use of the Topex-Poseidon dual-frequency radar altimeter over land surfaces
| Online Contents | 2003
Nonparametric Estimates of the Sea State Bias for the Jason-1 Radar Altimeter
| Online Contents | 2004