TY - JOUR
T1 - A Dual-Polarized Reconfigurable Reflectarray with A Thin Liquid Crystal Layer and 2D Beam Scanning
AU - Aghabeyki, Peyman
AU - Cai, Yang
AU - Deng, Guangsheng
AU - Tan, Zheng-Hua
AU - Zhang, Shuai
PY - 2023/4/1
Y1 - 2023/4/1
N2 - A novel approach for dual-polarized liquid crystal (LC) unit cell design is introduced, allowing significant thickness reduction of an LC layer without compromising its loss and phase shift. For each unit cell, LC is used for a tunable superstrate between a cross patch above and a square patch below. The square and cross patches are coupled through two slots for each polarization. By changing the voltage applied to the square and cross patches, the LC in-between varies the resonant frequency and phase of the unit cell to realize 2-D beam steering. 10× 10 dual-polarized reflectarray (RA) with 30μ m (0.0028 λ ) and 4μ m (3.73× 10-4λ ) thick LC layers are simulated in the 28 GHz band, where the aperture efficiencies (AE) are 25.3% and 22.5%, respectively. As a proof of concept, the dual-polarized RA with 30μ m thick LC is fabricated manually and measured at 28.5 GHz. A measurement technique is proposed to obtain the phase curves of the RA and reduce the effect of fabrication errors. With the imperfect manual fabrication, the RA still achieves the measured realized gain of 14.6 dBi corresponding to 12.5% AE. Besides, ±45° beam steering is demonstrated in the 2-D plane for both polarizations.
AB - A novel approach for dual-polarized liquid crystal (LC) unit cell design is introduced, allowing significant thickness reduction of an LC layer without compromising its loss and phase shift. For each unit cell, LC is used for a tunable superstrate between a cross patch above and a square patch below. The square and cross patches are coupled through two slots for each polarization. By changing the voltage applied to the square and cross patches, the LC in-between varies the resonant frequency and phase of the unit cell to realize 2-D beam steering. 10× 10 dual-polarized reflectarray (RA) with 30μ m (0.0028 λ ) and 4μ m (3.73× 10-4λ ) thick LC layers are simulated in the 28 GHz band, where the aperture efficiencies (AE) are 25.3% and 22.5%, respectively. As a proof of concept, the dual-polarized RA with 30μ m thick LC is fabricated manually and measured at 28.5 GHz. A measurement technique is proposed to obtain the phase curves of the RA and reduce the effect of fabrication errors. With the imperfect manual fabrication, the RA still achieves the measured realized gain of 14.6 dBi corresponding to 12.5% AE. Besides, ±45° beam steering is demonstrated in the 2-D plane for both polarizations.
KW - Beam-steering
KW - dual polarization
KW - liquid crystal (LC)
KW - reflectarray (RA)
KW - response time
UR - http://www.scopus.com/inward/record.url?scp=85148441290&partnerID=8YFLogxK
U2 - 10.1109/TAP.2023.3240853
DO - 10.1109/TAP.2023.3240853
M3 - Journal article
SN - 0018-926X
VL - 71
SP - 3282
EP - 3293
JO - I E E E Transactions on Antennas and Propagation
JF - I E E E Transactions on Antennas and Propagation
IS - 4
ER -