Dual-Linear Polarized 2-Bit Reconfigurable Transmitarray at Ku-Band

This communication proposes a 2-bit dual-linear polarized reconfigurable transmitarray (DLPRTA) operating at Ku-band. The independent dual-linear polarization unit cell consists of two mutually orthogonal subunit cells with identical structures. The subunit cell is a receiver-transmitter structure, which is composed of an active symmetrical receiving dipole and an active asymmetric transmitting dipole respectively integrated with a pair of p-i-n diodes. A total of four p-i-n diodes of each subunit cell realize four operating states of the 2-bit phase quantization. A DLPRTA prototype consisting of 22×22 unit cells was designed, fabricated, and measured. At 15.2 GHz, the maximum gains of the DLPRTA in x- and y-polarization are 24.65 dBi and 24.61 dBi, respectively, corresponding to the aperture efficiency of 23.85% and 23.59%. Its beam scanning capability has also been verified to cover the scan range of ±50° in both linear polarizations with side-lobe levels lower than 10 dB. The gain loss of the maximum angle beam scanning are 2.26 dB and 2.37 dB respectively, which proved good beam scanning performance.