A frequency reconfigurable microstrip antenna with radiation and scattering state switching

This letter presents the theoretical investigation by a transmission line model and the physical implementation of a novel frequency reconfigurable microstrip antenna with switchable states. More specifically, by using voltage-controlled PIN diodes, the antenna can be switched between a radiation state and a low-scattering state. In the radiation state, the operation frequency of the antenna can be electrically modified between 1.5 and 2.3 GHz by acting on the voltage applied to the varactors. In the low-scattering state, the antenna achieves a significant in-band radar cross section reduction, with a maximum value of 26.7 dB. The proposed antenna is fabricated and measured. The validity of the proposed strategy is verified by the good agreement between simulated and measurement results. The antenna designed by the proposed approach has great advantages in the radiation performance, aperture size, profile height and design freedom. This work indicates the feasibility of employing the reconfiguration technique to mnipulate the scattering features of an antenna without deteriorating its radiation characteristics.