Data Simulations

CPI has provided and continues to provide key support to satellite optical sensor programs through data simulations needed for sensor design, visualizing measurements over extended observing periods (e.g., over entire orbits), and testing software for routine data processing.  The key components in the simulation software are CPI first-principles models (e.g., AURIC and B3C.  Other key components are orbit models, routines providing sensor characteristics (e.g., calibration factors and observing geometries), scripts for production runs of first-principles models addressing extending observing periods, and visualization routines for displaying the simulations.  Recently, simulations have been performed for DMSP/SSUSI, DMSP/SSULI, MSX/UVISI, and the far ultraviolet imaging instrument on DE 1 [an example for the latter instrument may be seen in Strickland et al., J. Geophys. Res., 104, 4251, 1999].  Examples of full orbit simulations for SSUSI and SSULI may be seen in the following illustrations.

Simulation of full orbit of DMSP/SSUSI data for the 135.6 nm feature of atomic oxygen (dayglow, nightglow, and aurora).  X axis refers to a cross-track scanning angle while the y axis refers to an orbital angle.  Right side of image shows emission on the Earth's limb.  The projections on the right illustrate the geographical coverage along the DMSP orbit.
Simulation of full orbit of SSUSI OI 135.6 nm disk data (shown in quarter orbit segments) in counts with statistical errors.
Simulation of full orbit of SSUSI OI 135.6 nm limb data in counts with statistical noise.
Full orbit SSULI simulation for O+ 83.2 nm at summer solstice showing dayside on the right.  Earth center is at center of image with geographical north at top.  Emission is shown over the tangent altitude range from 100 to 1000 km.  Limb scanning is in plane of orbit that leads to contributions at each observing point from several degrees of latitude.  Brightness is in Rayleighs.
Similar to O+ 83.2 nm image but for OI 135.6 nm.
Similar to O+ 83.2 nm but for O+ 91.1 nm recombination emission.