• moving target detection;
  • over-the-horizon radar;
  • time-frequency distribution (analysis);
  • clutter rejection;
  • adaptive chirplet transform

[1] In over-the-horizon radar (OTHR) moving target detection, the signal to clutter ratio (SCR) is low for slow targets near the clutter, such as ships. One method to detect a moving target is to first reject the clutter and improve the SCR before the detection, such as the adaptive Fourier transform developed by Root [1998a, 1998b, 1998c] when a target moves uniformly. When a target does not move uniformly, the Fourier-based techniques for the target detection including superresolution techniques may not work well. In this paper, we propose an adaptive chirplet transform technique in the Doppler processing in OTHR as an alternative of the Fourier transform technique when a target moves nonuniformly.