Low-RCS and Polarization-Reconfigurable Antenna Using Cross-Slot-Based Metasurface

This letter presents a polarization-reconfigurable compact slot antenna with reduced radar cross section (RCS) using an asymmetric cross-shaped metasurface (MS). The proposed MS can reconfigure the polarization of the slot antenna between right-hand circular polarization (RHCP), left-hand circular polarization (LHCP), and linear polarization (LP) by rotating it with respect to the center of the slot antenna. In addition, the MS reduces the RCS of the slot antenna significantly in all polarization states. The cross-slot MS is placed just over the planar slot antenna without any air gap. The simulated monostatic RCS of -19.5 dBsm is observed at 4.4 GHz for LHCP and RHCP cases and -17.0 dBsm for LP mode of operation. Antenna performance in terms of its input matching, far-field parameters, monostatic RCS, and axial ratio are measured at its three polarization states, which are in agreement with simulated results.