1 Bit Dual-Linear Polarized Reconfigurable Transmitarray Antenna Using Asymmetric Dipole Elements with Parasitic Bypass Dipoles

Reconfigurable transmitarray antennas with independent dual-linear polarization phase controlling capability are essential for wireless communications applications. This work proposes a novel 1 bit transmitarray element design at Ku-band, which adopts the receiver-transmitter structure with an active receiving dipole and a passive asymmetric transmitting dipole. The 1 bit phase shift is achieved by alternating two p-i-n diodes integrated on the active dipole to reverse its current direction. To mitigate the influence of p-i-n diodes and reduce the element insertion loss, a parasitic bypass dipole is added next to each dipole. Element simulations show that a low loss of only 1.0 dB is achieved. The dual-linear polarization capability is obtained by orthogonally interlacing two sets of proposed receiver-transmitter structures. A 100-element transmitarray prototype is designed, fabricated, and measured. The measured gain is 18.3 dB at 12.2 GHz, corresponding to an aperture efficiency of 22.6%. The 2-D beam-scanning capability for independent dual-linear polarization is experimentally verified and the scan angle covers ±50°. The measured maximum scan gain loss is 2.9 and 3.5 dB in the two principal planes, respectively.