Application of attitude jitter detection based on short-time asynchronous images and compensation methods for Chinese mapping satellite-1.

Given the recent development in high-resolution (HR) optical satellites, the study of both attitude jitter (AJ) detection and compensation has become increasingly essential to improving the radiometric and geometric quality of HR images. A group of HR optical stereo mapping satellites in China, mapping satellite-1 (MS-1) has launched two satellites and will launch one satellite to build a satellite network. The geometric accuracy of the launched MS-1 satellites is greater than 80 m because of the AJ caused by the instability of the platform. AJ detection and compensation are critical issues that must be addressed to improve the accuracy of geo-positioning and mapping before launching a new satellite. The present study employs a method of jitter detection based on short-time asynchronous images to detect MS-1 jitter. The adjacent overlapping areas of an original panchromatic image are used as detection images instead of the traditional multispectral images, and a differential recursion optimal estimation filter is proposed for the optimal estimation and elimination of the gross errors of the registration data procedure, thereby increasing the detection accuracy. The space variant blurring model and viewing angles correction method are employed for the radiometric and geometric jitter compensation of images, respectively. The methods of radiometric objective evaluation indices and geometric checkpoint are then utilised to evaluate the quality of jitter compensation. Finally, the DeZhou regional image (ShanDong province, China) from MS-1 is used as the experimental data. Results for the AJ of MS-1 are analysed and reported for the first time. The assessment results obtained show that both radiometric and geometric qualities greatly increase after the jitter compensation procedure. Thus, the work of this study for jitter detection and compensation effectively addresses the jitter of MS-1 HR optical satellites.