In this approach, the object to be detected is abstracted as a set of pre-defined Points of Shape Characteristics (PSC)illustrated in figure 2, the EM-wave radar fires is represented as a closed geometry created by an elliptic cone and a plane, and then the radar detection process is transformed into a problem to find out the PSC illuminated by the EM-wave, or radar beam.

As figure 3 shows, the radar beam is assumed to be a close geometry named Radar View Volume(RVV) created by an elliptic cone and a plane and have the three property parameters: range R, azimuth angle [alpha], elevation angle [beta].