Synthetic aperture radar interferometry (InSAR) can gain three-dimensional topography with high spatial resolution and height accuracy using across track interferometry[1]. Conventional InSAR produce three-dimensional images from SAR data. But when the working wavelength transit from microwave to optical wave, the transmission antenna and receive antenna become very sensitive to platform vibration and beam quality[2]. Through differential receive antenna formation, we can relax the requirement of platform and laser using synthetic aperture imaging ladar (SAIL) concept[3]. Line-of-sight motion constraints are reduced by several orders of magnitude. We introduce two distinctive forms of antenna formation according to the position of interferogram. The first architecture can simplify the interferogram processing and phase extraction algorithm under time-division multiplex operation. The second architecture can process the 2D coordinate and height coordinate at the same time. Using optical diffraction theory, a systematic theory of side-looking SAIL is mathematically formulated and the necessary conditions for assuring a correct phase history are established[4]. Based on optical transformation and regulation of wavefront, a side-looking SAIL of two distinctive architectures is invented and the basic principle, systematic theory, design equations and necessary conditions are presented. It is shown that high height accuracy can be reached and the influences from atmospheric turbulence and unmodeled line-of-sight motion can be automatically compensated.

Date Published: 18 September 2014
PDF: 10 pages
Proc. SPIE 9227, Unconventional Imaging and Wavefront Sensing 2014, 92270D (18 September 2014); doi: 10.1117/12.2060470

Published in SPIE Proceedings Vol. 9227:
Unconventional Imaging and Wavefront Sensing 2014
Jean J. Dolne; Thomas J. Karr; Victor L. Gamiz, Editor(s)