Session
Weekday Session 3: Science/Mission Payloads
Location
Utah State University, Logan, UT
Abstract
The implementation of Imaging spectrometers with state-of-the-art performance on small satellites is challenging due to the size, weight, and power (SWaP) limitations. We have recently developed a compact form, the Chrisp Compact VNIR/SWIR Imaging Spectrometer (CCVIS), that facilitates their usage without sacrificing performance. The CCVIS enables a modular implementation that, combined with a freeform telescope, produces a wide field of view with high signal to noise ratio (SNR) performance. The targeted scientific application is the study of aquatic ecosystems. The imaging spectrometer is designed to address carbon sequestration in coastal margins and wetlands, kelp and seagrass studies, coral reefs, harmful algal blooms and hypoxia, and carbon cycling in this dynamic environment. The requirements are challenging since the high SNR, which is necessary in order to produce quality data products over water, is coupled with sufficient dynamic range in order to simultaneously record spectra from the shore area, which has elevated spectral radiance in comparison to the water. To meet these requirements, the small satellite will execute a pitchback maneuver where the imaging of the slit projected onto the surface is slowly scanned while recording focal plane array (FPA) readouts at a higher rate. The effective frame rate is determined by the time it takes to scan the projected slit one ground sample distance (GSD). This concept of operation avoids saturation over the land surface while obtaining high SNR over the water. This approach has the added benefit of measuring a range of angles during a single GSD acquisition, providing insight into the bidirectional reflectance distribution function (BRDF). One consequence of this approach is extremely large data volumes requiring a high bandwidth downlink system. Laser communications is a critical technology that enables the transfer of these large data volumes. We present a preliminary design of the imaging spectrometer based on the aquatic ecosystem requirements including the modular implementation of the CCVIS, the laser communications system, and the implementation on a "ESPA-grande" satellite.
Imaging Spectrometer Implementation on a Small Satellite Platform for Aquatic Ecosystems Science
Utah State University, Logan, UT
The implementation of Imaging spectrometers with state-of-the-art performance on small satellites is challenging due to the size, weight, and power (SWaP) limitations. We have recently developed a compact form, the Chrisp Compact VNIR/SWIR Imaging Spectrometer (CCVIS), that facilitates their usage without sacrificing performance. The CCVIS enables a modular implementation that, combined with a freeform telescope, produces a wide field of view with high signal to noise ratio (SNR) performance. The targeted scientific application is the study of aquatic ecosystems. The imaging spectrometer is designed to address carbon sequestration in coastal margins and wetlands, kelp and seagrass studies, coral reefs, harmful algal blooms and hypoxia, and carbon cycling in this dynamic environment. The requirements are challenging since the high SNR, which is necessary in order to produce quality data products over water, is coupled with sufficient dynamic range in order to simultaneously record spectra from the shore area, which has elevated spectral radiance in comparison to the water. To meet these requirements, the small satellite will execute a pitchback maneuver where the imaging of the slit projected onto the surface is slowly scanned while recording focal plane array (FPA) readouts at a higher rate. The effective frame rate is determined by the time it takes to scan the projected slit one ground sample distance (GSD). This concept of operation avoids saturation over the land surface while obtaining high SNR over the water. This approach has the added benefit of measuring a range of angles during a single GSD acquisition, providing insight into the bidirectional reflectance distribution function (BRDF). One consequence of this approach is extremely large data volumes requiring a high bandwidth downlink system. Laser communications is a critical technology that enables the transfer of these large data volumes. We present a preliminary design of the imaging spectrometer based on the aquatic ecosystem requirements including the modular implementation of the CCVIS, the laser communications system, and the implementation on a "ESPA-grande" satellite.
