Abstract's details
Possible S3A POD NRT improvements
CoAuthors
Event: 2016 Ocean Surface Topography Science Team Meeting
Session: Precision Orbit Determination
Presentation type: Type Poster
Contribution: PDF file
Abstract:
Possible improvements of the Sentinel 3A Near Real Time (NRT) POD towards the end of the interval
Sentinel-3 is running an operational GPS based Near Real Time (NRT) POD processing computed on ground, as compared to the Jason family where the NRT POD is provided by the onboard computed DORIS Navigator.
Sentinel-3 POD Instrument Processing Facility (IPF) runs at the Marine Centre located at EUMETSAT premises and computes the NRT GPS based POD for use in further processing of altimetry products. The system has been developed as part of the Copernicus POD Service by GMV S.A. from Spain.
The products have an accuracy requirement of 10cm (8cm goal) in the radial direction and shall be generated 30 minutes after level0 availability at the processor. The system is by far outperforming the requirement providing typically a radial accuracy below the 2cm.
As expected orbits are more degraded towards the end of the interval (see attached plot provided by the Copernicus POD service, corresponding to the projection of the radial error of the last half orbit before the downlink in Svalbard). Detailed analysis on the accuracy at the end of the determination arc will be provided, assessing the main source of the errors (e.g. GPS precise orbits and clocks used, solar activity, bathtub effect …) and some possible improvements will be studied with their effect on the products (e.g. changing the level0 dumping strategy, making more accurate auxiliary files available at the processor, updating the POD configuration, etc).
Sentinel-3 is running an operational GPS based Near Real Time (NRT) POD processing computed on ground, as compared to the Jason family where the NRT POD is provided by the onboard computed DORIS Navigator.
Sentinel-3 POD Instrument Processing Facility (IPF) runs at the Marine Centre located at EUMETSAT premises and computes the NRT GPS based POD for use in further processing of altimetry products. The system has been developed as part of the Copernicus POD Service by GMV S.A. from Spain.
The products have an accuracy requirement of 10cm (8cm goal) in the radial direction and shall be generated 30 minutes after level0 availability at the processor. The system is by far outperforming the requirement providing typically a radial accuracy below the 2cm.
As expected orbits are more degraded towards the end of the interval (see attached plot provided by the Copernicus POD service, corresponding to the projection of the radial error of the last half orbit before the downlink in Svalbard). Detailed analysis on the accuracy at the end of the determination arc will be provided, assessing the main source of the errors (e.g. GPS precise orbits and clocks used, solar activity, bathtub effect …) and some possible improvements will be studied with their effect on the products (e.g. changing the level0 dumping strategy, making more accurate auxiliary files available at the processor, updating the POD configuration, etc).
