Parametric Scattering Center Modeling for a Conducting Deep Cavity

A conducting deep cavity is an essentially geometric structure, e.g., the inlet duct and the tail nozzle, of air vehicles and is a dominant scattering source of radar echoes. The scattering centers (SCs) induced by multiple reflections inside deep cavities are different from general SCs. Few references have studied the SC model for deep cavities. Therefore, a concise SC model is presented in this letter. In this model, an analytical expression for the projection distances of SCs along the line-of-sight (LOS) in deep cavities is derived by using the ray- tracing method. Rectangular cavities, cylindrical cavities, and a cavity composed of two cylindrical structures are investigated in this letter. The presented SC models are validated by a comparison between the radar images simulated by the model and those computed by a full-wave numerical method.