Reconfigurable Folded Transmitarray Antenna With Low-Profile Based on Metasurfaces

A reconfigurable folded transmitarray antenna (RFTA) with fully planar structure is presented in this letter. It consists of an electronically reconfigurable metasurface and a polarization rotating metasurface (PRMS). A pair of PIN diode switches is integrated on the reconfigurable meta-atom to realize the 1-bit transmission phase manipulating, and a patch antenna is integrated on the center of the PRMS to feed the RFTA. Through twice reflecting, polarization rotating, and transmission phase compensation, the spherical wave from the feed is transformed into the scannable pencil-shaped beam. Meanwhile, the antenna profile is reduced to about 1/3 compared to the traditional reconfigurable transmitarray antenna (RTA). The RFTA prototype with 12 × 12 elements is designed, fabricated, and measured. Experimental results show that the gain of 13.4 dBi at 5.8 GHz is obtained and the two-dimensional beam scanning angle covers ±60°. This work significantly reduces the profile of traditional RTA, making it a promising candidate for the wireless communication system with limited space.