A Tri‐Functional Active Reconfigurable Retrodirective Array

ABSTRACT

With the continuous expansion of electromagnetic application scenarios for retrodirective systems, reconfigurable retrodirective arrays featuring multiple operating modes and flexible control capabilities have gradually emerged as an important research and application direction. In this paper, an active reconfigurable function‐switching network operating over 6.4–11.2 GHz is designed. A broadband filtering magneto‐electric dipole antenna is proposed that inherently fuses filtering selectivity with radiation, thereby effectively suppressing out‐of‐band interference without requiring additional filter circuits. By integrating the developed filtering magneto‐electric dipole antenna, a broadband active reconfigurable retrodirective array system with three functional states (absorption, active retrodirective array, and active phased array) is developed. In the active retrodirective mode, the developed system achieves a monostatic radar cross section (RCS) angular coverage of ± 50° (angular range within a 6 dB drop from the RCS peak) within the operating band, along with an RCS dynamic modulation range exceeding 20 dB. In the active beamforming mode, a 3‐dB beam scanning range of ± 45° is realised.