The analysis focusing characteristics of ellipsoidal antenna

In this paper the focusing characteristics of ellipsoidal antenna are analyzed, which is used for detecting objects hidden in people's body. And it is points out that the advantages of the ellipsoidal antenna having double focusing points, comparing to parabolic antenna in the condition of imaging in near-field. Through the analysis of axial focusing characteristics of even circular caliber antenna, some main parameters which influence axial focusing characteristics are obtained. Using statistics computational method and simulation of ellipsoidal conjugate imaging, the methods for designing ellipsoidal antenna, and the position of focusing spot and changing rule of radius in millimeter-wave imaging system are obtained. Comparing to parabolic antenna in the condition of imaging in near-field, ellipsoidal antennas have better focusing characteristics than parabolic antennas, but when the deviated focal distance increases, the focusing effect obviously changes poor. Therefore considering each kind of factor, based on practically suitable application parameter, the resolution of imaging system should be raised.