On-orbit tracking of sub-sample gain differences in SNPP and NOAA-20 VIIRS imagery bands

Kevin A. Twedt; Ning Lei; Xiaoxiong Xiong

doi:10.1117/12.2533125

Translator Disclaimer

10 October 2019 On-orbit tracking of sub-sample gain differences in SNPP and NOAA-20 VIIRS imagery bands

Kevin A. Twedt, Ning Lei, Xiaoxiong Xiong

Author Affiliations +

Proceedings Volume 11151, Sensors, Systems, and Next-Generation Satellites XXIII; 111512B (2019) https://doi.org/10.1117/12.2533125
Event: SPIE Remote Sensing, 2019, Strasbourg, France

Abstract

The VIIRS instruments on board the SNPP and NOAA-20 (N20) satellites have 14 reflective solar bands covering a spectral range from 412 nm to 2250 nm. Three of these are imaging bands (I bands) with a nadir spatial resolution of 375 m and 11 are moderate resolution bands (M bands) with a resolution of 750 m. The higher resolution in the I bands is achieved by a combination of more detectors, with the I bands having twice as many detectors of half the size for every M band detector, and a higher data rate, with the I bands having two sub-samples for every sample of M band data. To ensure calibration accuracy, any systematic difference in the response of the two sub-samples needs to be monitored and corrected in the calibrated products. In this paper, we use the solar diffuser calibrations to monitor the gain differences between the two sub-samples of the I bands both as a function of time and signal level. We find gain differences of about 0.1% for I1, 0.3% for I2, and <0.1% for I3 that are mostly constant over the range of signal values available in the SD calibration. These values are mostly consistent throughout the mission for both instruments. The results are remarkably similar for the two VIIRS instruments, including a slightly out-of-family behavior seen in a few detectors. We discuss possible causes for the difference and the impact on the aggregated Earth view images.

Citation Download Citation

Kevin A. Twedt, Ning Lei, and Xiaoxiong Xiong "On-orbit tracking of sub-sample gain differences in SNPP and NOAA-20 VIIRS imagery bands", Proc. SPIE 11151, Sensors, Systems, and Next-Generation Satellites XXIII, 111512B (10 October 2019); https://doi.org/10.1117/12.2533125

ACCESS THE FULL ARTICLE