Late-time resonance window estimation in radar

Radar target identification based on resonant frequencies requires analysis of the “late-time” portion of the target signature: the period when early-time scattering has ceased, the resonant frequencies are well established, and the signal can still be distinguished from the noise. While target geometry can be used to determine the late-time commencement, for uncooperative radar target identification the determination must be made on the basis of the signal data alone. Intrinsic features of the Hankel matrix of the target impulse response, such as its rank and the distribution of its singular values, can be used to identify the late-time start prior to full matrix-pencil analysis of the optimal processing window. Results are presented from simulated target data.