Research on a New Compound Antenna for Millimeter Wave/infrared Seeker

A novel design of the millimeter wave/infrared compound dual mode seeker antenna is presented in this paper with two-dimensional sum-difference angle measurement ability. By introducing the Infrared secondary mirror with the metallic coating, a shared aperture reflector antenna is designed with two independent working modes - MMW mode and Infrared mode, which shares the same seeker aperture area. Then, a miniaturized MMW feed is proposed with the integration of horn, sum-difference network and circulator. At last, the prototype antenna is fabricated and measured, showing that the gain can achieve as high as 36dB in the band of 92GHz-95GHz while the sidelobe can go down as low as -14dB. Meanwhile, the isolation of the ports can be as low as -20dB. Such excellent performance can enable this composite antenna extensively adopted in the precision guided weapon systems.