Shinya Kitagawa

Switchable reflector for radar cross section reduction of x-band dipole array

A switchable reflector using pin diodes for the radar cross section (RCS) reduction of an antenna reflector was proposed. The reflection coefficient of the proposed reflector was able to be switched between less than -20 dB with OFF-state diodes and more than -0.8 dB with ON-state diodes around 9 GHz. The proposed reflector with ON-state diodes was applied to the reflector of a dipole array antenna and equivalent radiation pattern to one with a metal reflector was obtained. Moreover, it with OFF-state diodes reduces the antenna RCS more than 10 dB at 9 GHz. Therefore it can contribute to the antenna RCS reduction at the radiation frequency without degrading antenna performance.

Active absorption/transmission FSS using diodes

An active frequency selective surface (FSS) which is switched as a radar absorber and transmission surface using pin diodes at the same frequency is proposed. The diodes are arranged on the both sides of the active FSS. The active FSS performs as a radar absorber and transmission surface with OFF- and ON-state diodes. The active FSS is fabricated and demonstrated. The measured reflection and transmission coefficient of the fabricated active FSS with OFF-state diodes are -27 dB and -17 dB at 9 GHz, respectively. The incident wave is absorbed by the active FSS. On the other hand, the transmission coefficient of that with ON-state diodes is -0.3 dB at the same frequency. The incident wave is transmitted through the active FSS.

A novel switchable reflector applied to antenna reflector for antenna radar cross section reduction

A switchable reflector using pin diodes for the radar cross section (RCS) reduction of an antenna reflector was proposed. The reflection coefficient of the proposed reflector was able to be switched between less than -25 dB with OFF-state diodes and more than -0.8 dB with ON-state diodes around 5 GHz. The proposed reflector with ON-state diodes was applied to a dipole antenna reflector and gave equivalent radiation pattern to with a metal reflector. It can contribute to the antenna RCS reduction at the radiation frequency without degrading antenna performance.