First In-Orbit Validation of Interferometric GNSS-R Altimetry

This dataset compiles the original figures utilized in the paper titled "First In-Orbit Validation of Interferometric GNSS-R Altimetry." In 2023, China successfully launched the world's first spaceborne interferometric GNSS-R (iGNSS-R) altimeter. This advanced instrument features dual-frequency, multi-beam scanning capabilities, interferometric processing, and compatibility with three major satellite navigation systems: the BeiDou Navigation Satellite System (BDS), the Global Positioning System (GPS), and the Galileo Satellite Navigation System (GAL).The figures included in this dataset depict typical coherent and incoherent interferometric waveforms collected over sea ice and open ocean surfaces, corresponding to BDS, GPS, and GAL, respectively. To enhance the accuracy of sea surface height (SSH) retrieval, we developed a refined Delay Mapping (DM) waveform matching algorithm. This algorithm precisely extracts the propagation delays between reflected and direct GNSS signals, enabling the retrieval of global SSH through the interferometric altimetry model. The dataset lists waveform matching cases for BDS iGNSS-R DMs.For validation, we employed an inter-satellite crossover approach, using Jason-3 and Sentinel-6 radar altimetry as references. This method achieved an unprecedented SSH accuracy of 17.2 cm at a 40 km resolution. The iGNSS-R altimeter experiment data used for inter-satellite cross-validation were collected from July 11, 2023, to December 29, 2023.During this period, we identified 127,862 crossover points with Jason-3 SSH products and 136,738 crossover points with Sentinel-6 SSH products for SSH product accuracy assessment. The comparative analysis results of sea surface height measurements are also included in this dataset.