Wideband RCS Reduction of Microstrip Patch Antenna Using Quaternionic Metasurface

ABSTRACT This paper presents a novel microstrip patch antenna with a quaternionic metasurface. The quaternionic metasurface is designed using a pair of polarization conversion metasurface unit cells and the other pair of artificial magnetic conductor unit cells. The designed metasurface is used to reduce the radar signature of a microstrip patch antenna. The designed quaternionic metasurface shows an overall RCS reduction bandwidth of 115.62% over the frequency range of 6.55–24.5 GHz and 10‐dB RCS reduction bandwidth of 65.86% over the frequency range of 8.3–16.45 GHz. The designed low RCS microstrip patch antenna using quaternionic metasurface shows overall RCS reduction bandwidth from 6.8 to 24.4 GHz (112.82%) as compared with the metallic plate and the reference patch for TE mode. It shows 10 dB RCS reduction bandwidth from 8.31 to 9.85 GHz (16.96%) and 12.38 to 16.34 GHz (27.58%) when compared with the reference patch for TE mode. Considering TM mode, the overall RCS reduction is obtained from 6.9 to 24 GHz (110.68%) as compared with the reference patch antenna. A total of 10 dB RCS reduction is observed over the frequency band of 8.4–9.89 GHz (16.29%) and 12.4–16.87 GHz (30.54%) as compared with the conventional patch antenna in the same plane. The low RCS patch antenna shows off remarkable in‐band and out‐of‐band RCS reduction. The proposed concept gives wide RCS reduction bandwidth that may not be obtained by the low RCS metasurface designed by only PCM or AMC unit cells.