Antenna pattern correction technique for near-field RCS measurement based on image

Practically, radiation patterns of antennas are not isotropic, and the amounts of energy radiated in different directions are not the same. In the near-field measurement, the large variety of antenna pattern in amplitude and phase will lead to significant errors. Thus, the RCS measured by a near-field method is different from that measured at the far field. In this paper, we present a near-field RCS measurement method based on modifying the pattern, which can suppress the error resulted from the directive beam of antenna pattern. Microwave imaging technique is employed to extract RCS. Numerical results show that the proposed approach is effective for antenna pattern compensation in near-field RCS measurement.