A New Combined Adjustment Model for Geolocation Accuracy Improvement of Multiple Sources Optical and SAR Imagery

Niangang Jiao,Hongjian You,Feng Wang

doi:10.3390/rs13030491

Abstract

Numerous earth observation data obtained from different platforms have been widely used in various fields, and geometric calibration is a fundamental step for these applications. Traditional calibration methods are developed based on the rational function model (RFM), which is produced by image vendors as a substitution of the rigorous sensor model (RSM). Generally, the fitting accuracy of the RFM is much higher than 1 pixel, whereas the result decreases to several pixels in mountainous areas, especially for Synthetic Aperture Radar (SAR) imagery. Therefore, this paper proposes a new combined adjustment for geolocation accuracy improvement of multiple sources satellite SAR and optical imagery. Tie points are extracted based on a robust image matching algorithm, and relationships between the parameters of the range-doppler (RD) model and the RFM are developed by transformed into the same Geodetic Coordinate systems. At the same time, a heterogeneous weight strategy is designed for better convergence. Experimental results indicate that our proposed model can achieve much higher geolocation accuracy with approximately 2.60 pixels in the X direction and 3.50 pixels in the Y direction. Compared with traditional methods developed based on RFM, our proposed model provides a new way for synergistic use of multiple sources remote sensing data.

Highlights

With the development of satellite imaging technology, it is increasingly common to obtain repeated observations of the same object from multiple sources in a short time, which provides dozens of imagery widely used in many fields, such as 3D reconstruction [1], change detection [2] and semantic classification [3]
The results indicated that the performance of the rational function model (RFM) and the rigorous sensor model (RSM) are nearly the same, and the plane accuracy without any ground control points (GCPs) can reach about 2.3 m [20]
The RSM is composed of various on-orbit information of satellite platforms, which leads to a complicated form

Summary

Introduction

With the development of satellite imaging technology, it is increasingly common to obtain repeated observations of the same object from multiple sources in a short time, which provides dozens of imagery widely used in many fields, such as 3D reconstruction [1], change detection [2] and semantic classification [3]. The application of multiple sources airborne and spaceborne remote sensing imagery is increasing popular in archaeological and cultural heritage as a supplement to traditional methods [4], which will provide sufficient texture information. Terrestrial results obtained by laser scanning suffer from high cost and missing data, whereas the combination of photogrammetry provides an affordable and practical approach for the production of 3D models. The application of airborne remote sensing images is widespread due to its high resolution which will provide enough details of buildings. Proposed a methodology by intergrating laser scanning and image-based 3D reconstruction techniques for the the production of 3D models [5].

Methods

Results

Conclusion