Abstract
The Atmospheric Waves Experiment (AWE) is the first dedicated NASA mission to study gravity waves in the upper atmosphere. The instrument built for this mission is the Advanced Mesospheric Temperature Mapper (AMTM). The AMTM is a wide field of view (FOV) imaging radiometer that will produce temperature maps of gravity waves near the mesopause region.
The AMTM instrument is comprised of four telescopes that each observe a single narrow band in the near-infrared, which together enable the temperature measurements through a background-subtracted ratio of OH emission line radiances. The AMTM’s large FOV results in significant optical distortion in the sensor’s imaging performance, which needs to be accounted for when producing pixel line-of-sight (LOS) vectors for on-orbit science data-processing. Pixel LOS vectors play a critical role in the overall geolocation algorithm while the AMTM is on orbit, as they describe the direction that the center of every pixel in the FOV for each telescope views out into object space. Accurate pixel LOS mapping is also required to effectively perform the temperature measurements since images from each telescope will not map to exactly the same region in object space due to relative misalignments between the telescopes/focal plane arrays (FPAs). The pixel LOS mapping and telescope co-alignment calibration was performed through a test completed during the AMTM flight model calibration campaign that was performed at Space Dynamics Laboratory (SDL) in September and October of 2022. This test involved scanning a collimated beam across the AMTM FOV to sample FPA coordinates in each telescope that correspond with specific source directions. This test and the corresponding data analysis were also used to characterize the AMTM FOV, instantaneous field of view (IFOV), and distortion magnitude.
This presentation will give an overview of the method used to perform the AMTM pixel LOS mapping and telescope co-alignment calibration, including details on the test configuration and setup, the data collection and analysis, and the relevant results.
Distortion, Pixel Line-of-Sight Mapping, and Telescope Co-alignment Calibration for the Atmospheric Waves Experiment (AWE) Advanced Mesospheric Temperature Mapper (AMTM)
The Atmospheric Waves Experiment (AWE) is the first dedicated NASA mission to study gravity waves in the upper atmosphere. The instrument built for this mission is the Advanced Mesospheric Temperature Mapper (AMTM). The AMTM is a wide field of view (FOV) imaging radiometer that will produce temperature maps of gravity waves near the mesopause region.
The AMTM instrument is comprised of four telescopes that each observe a single narrow band in the near-infrared, which together enable the temperature measurements through a background-subtracted ratio of OH emission line radiances. The AMTM’s large FOV results in significant optical distortion in the sensor’s imaging performance, which needs to be accounted for when producing pixel line-of-sight (LOS) vectors for on-orbit science data-processing. Pixel LOS vectors play a critical role in the overall geolocation algorithm while the AMTM is on orbit, as they describe the direction that the center of every pixel in the FOV for each telescope views out into object space. Accurate pixel LOS mapping is also required to effectively perform the temperature measurements since images from each telescope will not map to exactly the same region in object space due to relative misalignments between the telescopes/focal plane arrays (FPAs). The pixel LOS mapping and telescope co-alignment calibration was performed through a test completed during the AMTM flight model calibration campaign that was performed at Space Dynamics Laboratory (SDL) in September and October of 2022. This test involved scanning a collimated beam across the AMTM FOV to sample FPA coordinates in each telescope that correspond with specific source directions. This test and the corresponding data analysis were also used to characterize the AMTM FOV, instantaneous field of view (IFOV), and distortion magnitude.
This presentation will give an overview of the method used to perform the AMTM pixel LOS mapping and telescope co-alignment calibration, including details on the test configuration and setup, the data collection and analysis, and the relevant results.