A Dual-Polarized Spoof Surface Plasmon Polaritons Antenna with Wide Bandwidth and High Gain-Stability

This paper presents a compact dual-polarized endfire antenna based on spoof surface plasmon polaritons (SSPP). The fabricated prototype exhibits an overlapped impedance bandwidth of 87.08% (3.43-8.72 GHz) for both polarizations, a measured isolation better than 22 dB, a measured peak gain of 13.1 dBi, and a 3-dB gain bandwidth exceeding 76%, while maintaining a compact transverse dimension of only 0.46λ_L × 0.46λ_L (λ_L is the free-space wavelength at the lowest operating frequency). The proposed design offers a new solution of dual-polarized endfire antenna employing SSPP for high gain and ease of wideband impedance matching, which would be attractive in wireless communication systems such as target detection and electronic countermeasures.