A circularly polarized antenna with low RCS using chessboard grid hollow substrate

In this Letter, the chessboard grid hollow substrate (CGHS) is firstly presented to enhance the scattering performance of circularly polarised metasurface antenna. Grounded structures and AMCs are designed into chessboard arrangement as radiator. The CGHS installed at the upper of original antenna diversifies the thickness of adjacent subarrays. In contrast to previous chessboard arrangements, the 180 ° ± 37 ° reflection phase difference could be more easily realised for radar cross-section (RCS) reduction (less than − 10 dB). By straightforwardly adjusting the reflection phase, this design realises a peak RCS reduction of − 31.6 dB at 14 GHz, dramatically reduces RCS from 7 to 20 GHz. Moreover, simulated results demonstrate CGHSs optimise the monostatic RCS reduction average at the operating bandwidth, approximately − 5 dB . Meanwhile, this design also yields a VSWR ≤ 2 impedance matching bandwidth at 9.14–11.76 GHz and a less than 3 dB axial ratio bandwidth at 9.76–10.66 GHz.