Forward-looking SAR imaging using a linear array with transverse motion

The authors present a novel high-resolution forward-looking two-dimensional synthetic aperture radar (SAR) imaging technique based on discrete Fourier transform (DFT) processing and sequential mode operation. The system utilizes a linear phased array in transverse motion with respect to the flight path and the radar line of sight. No range gating is required. Multitarget detection is achieved on the basis of angular (azimuth and elevation) coordinates. The technique uses an improved signal model based on a third-order three-dimensional Taylor series expansion of the round-trip delay about incremental time, azimuth, and elevation. Computer simulation and an example show the impulse invariance and demonstrate the system´s performance