Model SENSAT: a tool for evaluating the system performance of optical sensors

Model SENSAT (Sensor-Atmosphere-Target) is a tool for evaluating the radiometric system performance of passive optical sensors. In combination with the LOWTRAN-7 code the model can be employed in the spectral range 0.20-28 microns. The model is capable of treating up to three homogeneous objects in the sensor's instantaneous field of view. It calculates the emitted/reflected radiance contribution of each object at the sensor, the SNR, the brightness temperature (IR sensors), and derived quantities such as the detector signal, and associated quantized (A/D converted) digital numbers. Special features include the multiple path option (sun-earth-target-sensor), a noise model for quantum detectors, a spectral band optimization, and a multi-band sensor option, which processes a sequence of contiguous spectral bands (e.g. high resolution spectrometer). Besides the system performance prediction the model can also be employed to process images of spaceborne/airborne optical sensors by performing the atmospheric correction and calculating ground reflectance images.