US 2025/0137849 A1 · GROUND REFERENCE TARGET AND VICARIOUS RADIOMETRIC CALIBRATION SYSTEM INCLUDING THE SAME

Abstract

Disclosed is a vicarious radiometric calibration system. More specifically, disclosed is a ground reference target for calibrating a digital signal that is obtained through a sensor when a landmark is observed from a satellite or an airplane by using a spectral reflection factor or spectral emissivity of the ground reference target and a vicarious radiometric calibration system including the same. It is possible to derive accurate measurement results for the MWIR region by installing a ground reference target having predetermined reflectance or emissivity and having a special form on the ground with respect to the calibration of a sensor for remote exploration, such as aviation, space, and astronomy, and performing absolute radiometric calibration by using images that are obtained through the ground reference target.

Claims8

Dependent claims

A ground reference target, wherein:

the ground reference target is a structure that is installed on a ground, and
the ground reference target comprises:
a body part that has a width of M (M is a rational number) meters, a height of N (N is a rational number) meters, that has an upper part opened, and that has an internal space in which water is accommodated formed therein;
and
an upper plate part that is coupled to a top of the body part, in which a plurality of cells is formed, and that is made of a metal material,
wherein a perforation having a predetermined diameter is formed in each of the plurality of cells, and
average radiance of a metal region and a perforation region for each cell is observed because at least one cell corresponds to one pixel of a sensor upon photographing of the sensor.

4 more elements

A vicarious radiometric calibration system comprising:

one or more ground reference targets installed on a ground and each comprising at least one metal region and perforation region and in which a plurality of cells each having predetermined reflectance or emissivity is formed;
a sensor mounted on an airplane that flies at a predetermined altitude above an Earth's surface and configured to photograph the ground reference target and to obtain an image in which average radiance for each cell is observed as each of the plurality of cells corresponds to at least one pixel of the sensor;
and
a vicarious radiometric calibration apparatus configured to receive the image and to perform vicarious radiometric calibration that converts a radiance value of the ground reference target into a digital number (DN).

1 more element

Dependencies are inferred from the claim text.

Ground reference target and vicarious radiometric calibration system including the same

Life of this patent

Ground reference target and vicarious radiometric calibration system including the same

Life of this patent

Abstract

Claims8