High-Radiation Efficiency in Array Antennas Using Cu/Co Metaconductors

High radiation-efficient
$4\times 4 $
array antennas consisting of multiple nanolayered nonmagnetic copper (Cu) and ferromagnetic cobalt (Co), termed as Cu/Co metaconductor, are reported for 5G and millimeter-wave applications. The performance of a ten paired Cu/Co metaconductor-based array antenna, where the thickness of each metal layer is 150 and 25 nm, respectively, is compared with that of two reference antennas. The first reference antenna has the same total thickness but is made of sputtered solid copper and the second one made of five times thicker electroplated solid copper. Because of eddy current cancellation and skin effect reduction in metaconductor, the Cu/Co-based antenna shows lower RF resistance in both feeding lines and antenna patches than reference antennas in
$K_{a}$
-band. Nearly 6 dB enhancement in the received signal power and the bandwidth (BW) improvement of 0.18 GHz is obtained for the Cu/Co-based antenna compared to the reference ones. Also shown is the possibility of more than 80% conductor weight reduction without losing antenna performance. Analysis for the enhancement in the antenna gain and BW is provided. Simulations performed in a high-frequency structural simulator are compared with the measured results. The total area of a fabricated
$4 \times 4$
array antenna is 5.6 cm
²
.