Method for multi-spectral radiation calibration of unmanned aerial vehicle

Abstract

The invention discloses a method for multi-spectral radiation calibration of an unmanned aerial vehicle in the technical field of unmanned aerial vehicle remote sensing, an existing unmanned aerial vehicle can obtain hundreds of images or even thousands of images in one sort. Only a plurality of images containing reference objects with known reflectivity exist, and the application of radiation correction coefficients obtained by only several reference objects to all the images is obviously unreasonable due to the continuous change of illuminance and shooting angles of the unmanned aerial vehicle during flight. The method comprises the following steps: 1, measuring a radiation spectrum by a micro spectrometer; mounting a spectrometer behind a diffuser optical element to provide a near-Lambert field of view, and outputting irradiance in absolute units according to the ASD FieldSpec Pro calibration system; 2, in order to measure the irradiance at different inclination angles, installing three RGB + Pan photodiodes on the frame, wherien each photodiode inclines by 10 degrees from the zenith to the opposite direction; and 3, like a spectrograph, dismounting the photoelectric tube from adiffuser, and irradiance output is calibrated.

Description

technical field [0001] The invention relates to the technical field of remote sensing of unmanned aerial vehicles, in particular to a method for multi-spectral radiation calibration of unmanned aerial vehicles. Background technique [0002] UAV remote sensing is a research hotspot in the field of remote sensing applications. With the advantages of simple structure, low cost, flexible maneuverability, and high temporal and spatial resolution of images, the UAV remote sensing system is gradually becoming an effective supplementary means for satellite remote sensing, man-machine remote sensing, and ground remote sensing. UAVs can be divided into micro, small, medium and large UAVs according to the quality of the aircraft. Among them, micro UAVs refer to UAVs with a maximum take-off mass of less than 5kg, a maximum flight altitude of less than 250m, a battery life of less than 1h, and a communication radius of less than 10km. Micro UAVs fly under the clouds. In cloudy weather,...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method for multi-spectral radiation calibration of unmanned aerial vehicles to solve the problem that one sortie of existing unmanned aerial vehicles proposed in the above background technology can acquire hundreds or even thousands of images, which contain known There are only a few images of reference objects for reflectivity. Due to the constant changes in illumination and shooting angles during the flight of the drone, it is obviously unreasonable to apply the radiation correction coefficients obtained from only a few reference objects to all images.