Enhanced High-Gain Antenna Design With Phase-Controlled Frequency Selective Rasorber for Low-RCS Performance

The development of antenna systems that effectively balance low scattering with robust radiation performance is a key focus in antenna research. This study introduces an innovative frequency-selective rasorber designed to precisely control the transmission phase within a lossless layer. This integration results in high gain, high directivity, and effective stealth characteristics in antenna design. The transmission phase and frequency response of the lossless layer element are carefully tuned by the coupled resonator within its multilayer structure. Additionally, the impedance matching between the lossless layer and the lossy layer is finely tuned to optimize the electromagnetic (EM) absorption and reduce the radar cross section (RCS). The proposed phase-controlled rasorber achieves a gain of 20.2 dB at 9.8 GHz and significant RCS reduction for bipolar polarized EM waves at lower frequencies, illustrating excellent radiation efficiency and stealth capabilities in antenna design.