Interferometric synthetic aperture ladar using code division multiple access apertures

This paper describes a multi-static interferometric synthetic aperture ladar (IFSAL) for high-resolution, high-precision 3D imaging. Code division multiple access apertures with periodic, pseudorandom noise waveforms are used to create aperture diversity and overcome the ambiguity associated with the aperture separation requirements for interferometric synthetic aperture ladar. The basic theory for mapping relative aperture phase to a high-precision elevation profile is derived for a multi-static IFSAL system and subsequent processing steps are presented. An analytic model and computer simulation are developed to demonstrate the 3D imaging capability of an IFSAL system.