Broadband circularly polarized leaky‐wave antenna based on spoof surface plasmon polaritons

Abstract

A broadband circularly polarized (CP) leaky‐wave antenna fed by spoof surface plasmon polaritons (SSPPs) is proposed in this paper. The antenna consists of SSPPs transmission line and the periodic open rings. The periodic open rings are loaded at both sides of the transmission line with 90° phase shift to obtain CP responses. Meanwhile, the antenna can obtain a wide‐angle beam scanning due to the dispersion characteristics of SSPPs. The simulated results indicate that the antenna has a wide CP impedance bandwidth of 44.9% from 3.8 to 6 GHz with a return loss smaller than −10 dB and the antenna axial ratio (AR) lower than 3 dB. Also, the antenna has a wide scanning angle that ranges from −54° to +10°. For validation, the antenna was fabricated and the measured results agreed well with simulated ones.

A Broadband Bidirectional Circularly Polarized Phase-Inverter-Based Periodic Leaky-Wave Antenna With Same Handedness

“…In the proposed design, the all-pass property of the PI ensures a very broadband matching, so the limiting factor is the AR across the scanning range. Nonetheless, our design exhibits a wide AR bandwidth of 40%, outperforming all fixed-beam antennas and second only to the PLWA in [27]. Yet, our scanning range is 19° wider, not to mention that the CP beams are of opposite handedness in [27].…”

“…Nonetheless, our design exhibits a wide AR bandwidth of 40%, outperforming all fixed-beam antennas and second only to the PLWA in [27]. Yet, our scanning range is 19° wider, not to mention that the CP beams are of opposite handedness in [27]. The largest scanning range is achieved by the antenna system in [31], but, as discussed in the introduction, the comparison between this system, incorporating four LP PLWAs and a coupler, and our standalone antenna is not fair.…”

“…Unlike unidirectional CP PLWAs, much fewer bidirectional CP PLWAs have been published. They are mostly based on groundless structures with inherent bidirectional radiation, such as the planar Goubau lines loaded with circular split ring pairs [24] or orthogonal dipole pairs [25], and the spoof surface plasmon polariton (SSPP) lines loaded with cloven circular patches [26], open rings [27], or dipoles [28]. In [24]- [28], the unit cells resemble an electric dipole rotating around the z-axis.…”

Leaky wave antenna with backfire to endfire beam-scanning capability based on even mode spoof surface plasmon polaritons

“…Due to the flexibility of the design, LWAs based on spoof surface plasmon polaritons (SSPPs) have attracted great attention in recent years [8][9][10][11][12][13][14][15][16][17]. For SSPP-based LWAs, most of them are based on the symmetrical even mode excited SSPPs, which makes it difficult to radiate beam in the backfire or endfire direction [17].…”