Radar Target Discrimination Based on Co-null Polarization State: A Resonance Mode Context

The concept of co-polarization null states is established in a resonance mode context to describe a radar target of interest. This is achieved by Singularity Expansion Method to represent the target transient response by its natural resonance modes. Therefore the polarization description of the target is based on a quadrature residue matrix at each resonance mode. The co-polarization null states are derived by Lagranian optimization of the second moment properties of the quadrature residue matrix. A wire model of aircraft is used to demonstrate the ability of co-null states based resonance to convey the target complex composite like elongation and tilt degrees.