Elevation measurement from single-pass SAR images

Abstract

Elevation measurement using Synthetic Aperture Radar (SAR) is one of fundamental techniques in remote sensing. The cross-track Interferometric SAR (InSAR), which is the most popular technique of elevation measurement using SAR, uses the phase differences between the signals received by SAR antennas. Single-pass InSAR can be achieved by a single platform with two antennas. InSAR requires Ground Control Points (GCPs) to measure absolute elevation values, although it is a time-consuming and cost-intensive task to acquire GCPs. Addressing the above problem, this paper proposes an elevation measurement method using two SAR intensity images taken by a single-pass airborne SAR system. A projection model is derived to apply the principle of stereo vision to elevation measurement from SAR images. Phase-Only Correlation is employed to obtain accurate correspondence between two SAR images having below 1-pixel disparities. Through the experiment using SAR images, we demonstrate that the proposed method exhibits efficient performance in elevation measurement.