Determination of resonance poles of radar targets in narrow frequency bands

In resonance domain, the radar scattering response of any object can be modelled by natural poles of resonance with the formalism of the singularity expansion method. The mapping of these poles in the complex plane gives useful information for the discrimination of a radar target, as its general shape, its characteristic dimension and its constitution. However, the full frequency band corresponding to the resonance domain of a radar target is not always available, thus it is often necessary to look for a compromise. In this paper, we propose to show that it is possible to extract resonance poles one-by-one in tuning a reduced frequency band to the frequency of each wanted pole. This avoids the use of ultra wide band (UWB) data and allows to extract at least some dominant poles of resonance in available narrow frequency bands.