ABSTRACT
Discrete Fourier transform (DFT) has found tremendous applications in almost all fieldsmainly because it can be used tomatch the multiple frequencies of a stationary signal with multiple harmonics. In many applications, wideband and nonstationary signals, however, often occur. One of the typical examples of such signals is chirp-type signals that are usually encountered in radar signal processing, such as synthetic aperture radar (SAR) and inverse SAR (ISAR) imaging. Due to the motion of a target, the radar return signals are usually chirps and their chirp rates include the information about the target, such as the location and the velocity.
