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This paper examines the feasibility and potential benefits of enhancing the spatial resolution of the VIIRS DNB channel for the JPSS-2 mission and beyond, by modifying the on-chip pixel binning recipe used in the DNB CCD to aggregate detector area within the scan swath. Presently the DNB delivers 16 cross-scan samples similar in size to the detectors in the VIIRS Moderate Resolution Bands. The relatively low-cost enhancement proposed would instead bin the pixels of the existing DNB CCD into 32 cross-scan samples, each half as large in track and scan, effectively doubling the spatial resolution of DNB in each dimension to match the VIIRS Imaging Bands at nadir. Other potential benefits include, for unresolved point sources, improved detection sensitivity and SNR. Smaller DNB image pixels would be less spatiallymixed, and therefore better suited to many quantitative analyses. DNB geolocation accuracy would also benefit from the increased spatial resolution, but less so for regions approaching edge-of-scan. To implement the maximum DNB spatial resolution enhancement over the full cross-track scan swath would require design and hardware modifications to the focal plane electronics (FPIE) to increase certain CCD clock rates. This paper explores the performance of this option, alongside other options that (if constrained to use the existing FPIE design with minimal changes) would not provide the enhanced DNB spatial resolution all the way out to the edges of the cross-track scan. These would instead offer other benefits, such as better maintaining SNR to edge-of-scan and, if away from nadir DNB sampling matched the I-bands, better enabling future environmental products merging the enhanced DNB data with existing VIIRS spectral band data.

Traditionally, daylight and night vision imaging systems have required image intensifiers plus daytime cameras. But SRI’s new NV-CMOS™ image sensor technology is designed to capture images over the full range of illumination from bright sunlight to starlight. SRI’s NV-CMOS image sensors provide the low light sensitivity approaching that of an analog image intensifier tube with the cost, power, ruggedness, flexibility and convenience of a digital CMOS imager chip. NV-CMOS provides multi-megapixels at video frame rates with low noise ( Unlike conventional image intensifiers, the NV-CMOS image sensor outputs a digital signal, ideal for recording or sharing video as well as fusion with thermal imagery. The result is a substantial reduction in size and weight, ideal for SWaP-constrained missions such as UAVs and mobile operations. SRI’s motion adaptive noise reduction processing further increases the sensitivity and reduces image smear. Enhancement of moving targets in imagery captured under extreme low light conditions imposes difficult challenges. SRI has demonstrated that image registration provides a robust solution for enhancing global scene contrast under very low SNR conditions.