Research of On-orbit MTF Measurement for the Satellite Sensors

摘要

Modulation Transfer Function (MTF) is significant in evaluating the performance of optical imaging system. Its value lies in that it can reflect the quality of imaging system directly. Especially due to the impact of the platform launch, it is important to measure the MTF value of the sensors at the moments when images are being captured. In other words, it is important to conduct on-orbit MTF detection for imaging systems. The on-orbit MTF value directly reflects the performance of imaging sensors in many applications and research. This paper introduces the theoretical basis and the principle of on-orbit MTF measurement with remote sensing images, and then it systematically summarizes the calculation process of knife-edge method, pulse method, point light source method and the periodic target method. With the images of CBERS-02C satellite and ZY-03 satellite, the four methods for measuring the on-orbit MTF value have been tested. The test results and other factors, such as the nature feature selection and the construction of artificial targets, are taken into account. This paper compares different methods of on-orbit MTF measurement to find the most suitable one that can be used with different satellite sensors.