A Space-Borne InSAR Image Registration by Aided by a Voronoi Diagram

In the InSAR co-registration procedure, the transform model between images in image pair can be fitted by the rational polynomial, and model parameters can be inverted by tie points at high accuracy and uniform distribution. However, traditional algorithms consider neither the importance of tie points or take into account the spacial distribution of tie points, which reduces the polynomial fitting accuracy. This paper proposes a Voronoi diagram based co-registration algorithm. It takes into account both weight and distribution of tie points. The algorithm was applied to process X band interferometry images acquired by the Cosmos-Skymed-1/2 satellite from somewhere in the west China. Compared to traditional methods, tests show that the Voronoi diagram based algorithm improves the correct matching ratio, acquires tie points at higher coherence with more uniform spatial distribution, thus achieving transform parameters at higher precision.