Radar target recognition based on some invariant properties of the polarization scattering matrix

In order to meet the needs of radar target recognition (RTR), a method using some invariant properties of the polarization scattering matrix (IPPSM) is presented. A simulated cone model of missile is used to test in microwave darkroom experiments, a new IPPSM is first presented, its physical characteristic is also given. All the IPPSMs are analyzed, the experiment results imply that Determinant |Δ|, Trace of Power Scattering Matrix P₁, Module of Polarization Ellipticity |τ₀|, Polarization Combination Coefficient η are invariant with the orientation angles. From the Depolation D, Polaization Ellipticity τ₀, we know that the target has multi-scattering centers and is symmetric which are true for the real target, so a 7-dim polarization vector X=(|Δ|, P₁, D, φ₀, τ₀, |τ₀|, η) can be usefully obtained for radar target recognition.