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N94- 25499

Simulation of a Passive Millimeter Wave Sensor i /_i __)

William W. Kahlbaum /_. /,_

Lockheed Engineering and Science Corporation

ABSTRACT

The visual display expected to be generated by a Passive Millimeter Wave (PMMW)

camera and sensor system has been simulated on a Silicon Graphics IRIS workstation at

the NASA Langley Research Center (LaRC). The low resolution of the sensor has been

simulated by graphically manipulating the scene as it is being drawn by the IRIS in real

time. Camera field of view, sensor resolution, and sensor update rate are the con-

trollable parameters. Physical effects such as lens model, radome effects, and noise

have not been included at this time. An approximate dynamic model of the atmo-

spheric phenomenology has been included which generates the gray-scale intensity

values in real time for the simulated image. The gray-scale values are proportional to

temperature. A snapshot capability which captures individual image frames during

real-time operation has been included. These images were used to validate the approx-

imate phenomenology model against a more rigorous physical model.

163

https://ntrs.nasa.gov/search.jsp?R=19940021007 2020-05-06T13:07:56+00:00Z

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