Spectral domain analysis of downward-looking linear array SAR three-dimensional imaging

This paper presents downward-looking three-dimensional SAR with linear array that distributed along cross-track direction. In contrast to conventional side-looking SAR, downward-looking three-dimensional SAR could create a real three-dimensional resolution image to avoid shading and layover effects. Imaging performances such as cross-track resolution and Doppler ambiguity are analyzed in this paper based on three-dimensional spectral domain. The maximum array elements spacing which should be satisfied to avoid cross-track Doppler ambiguity is proposed. The demonstration of spectral domain analysis and imaging performances are validated in the last part of this paper.