Asymmetric tri‐band linear‐to‐circular polarization converter in transmission mode

A multiband circular polarization selective metasurface for microwave applications

“…of bands No. of layers Thickness (mm) 26 − 30.1 No 2 2 0.008 28 30.1 No 4 3 1.1 27 21.45 No 3 3 1.2 29 < 10 No 1 2 1.5 30 − 21.1 No 2 2 1.5 31 20.74 No 2 2 1.5 32 37.3 No 1 2 1.524 This work 47.16 Up to 45° 4 2 1.57 …”

“…Here + and − represent the right-hand circular polarization (RHCP) and left-hand circular polarization (LHCP), respectively. The T.C cir matrix can be transformed to the Cartesian basis such as 27 , 32 : …”

“…The multiband circular polarization selectivity was achieved using multi-layered metallic structures on substrate sheet when they only operated at normal incidence 27 , 28 . The multi-layered structures cause high transmission loss, while reflection coefficient increase due to poor wave impedance matching 32 .…”

“…Various techniques have been reported on the asymmetric linear-to-linear polarization area through the use of bi-layered 22,23 and multi-layered 24,25 chiral structures. Currently, scientific community has directed attention towards realizing asymmetric linear-to-circular polarization [26][27][28][29][30][31][32] . As it is a challenging task to achieve asymmetric linear-to-circular (CPS) like the ones in 27,28,32 , however, multi-layered structures can be deployed where multi-band or enhanced bandwidth is required.…”

A circularly polarized TEM to TE 11 mode converter antenna

“…The structure is never suitable for high-power microwave (HPM) applications. In [26,27], sectorial MCA is investigated. Their sidelobe levels are significant.…”