Study Of Target Recognition Based On Bistatic Shadow Inverse Synthetic Aperture Radar

Shadow inverse synthetic aperture radar (SISAR) is a bi-static forward scattering barrier radar. SISAR is well suitable for the detection of stealth target by using the forward scatting signal from the target. SISAR plays an important role in the face of electronic jamming, low-altitude surveillance, stealth arms and anti-radiation missile (ARM). First, the principle of the shadow imaging is induced from the bi-static radar equation. The representation of radio holographic signal (RHS) is introduced; Then, The effect of flight altitude on target shadow image is analyzed and the method of fetching the feature for target recognition using the distance of shadow image' polar is presented. The relation between a phase of shadow image and a phase of midline of shadow profile is analyzed, and the method of reconstructed phase of midline of shadow profile by using phase of shadow image is discussed, the effects on phase of midline of shadow profile due to non-constant velocity rotation relative to the target and the azimuth angle of target are examined, and the method of eliminating this effect by meaning of normalization of difference of midline of shadow profile is presented. At last, the arithmetic of the radar cross section (RCS) of targets in the system of the bi-static forward scattering barrier radar is introduced. Relationship of the radio holographic signal with the radar cross section (RCS) of targets is induced. A method of calculating the power spectral density by calculating the RCS of targets is presented. Target recognition features are extracted by means of normalization of the power spectral density, which reduces the influence of the parameters of radar configure, the altitude and the elevation angle variety of the target.