Wideband Flush-Mounted Surface Wave Antenna of Very Low Profile

Abstract

This paper presents the design of a compact and wideband surface wave antenna that exhibits very low profile and can be flush-mounted on a conformal platform. The proposed antenna comprises a tapered grounded ceramic slab, a unidirectional surface wave launcher, and a tapered impedance transition. The ceramic slab is smoothly tapered to transform the guided surface wave into radiated space wave over a wide frequency range. The surface wave launcher employs a probe-fed parallel plate waveguide with a modified parabolic reflecting wall and a metallic post, which are critical for effectively transforming the cylindrical waves to a unidirectional plane wave within a broad frequency range. Simulated results show that the proposed surface wave antenna achieves a wide operation bandwidth from 6.1 GHz to 18 GHz with a thickness of only 0.12 at the center frequency. Acceptable gain values with stable and quasi end-fire radiation beams are obtained over the entire frequency band. A prototype of the proposed antenna is fabricated and tested. Measured results are in good agreement with simulated ones.Index Terms-Flush-mounted, low-profile, surface wave antenna, surface wave launcher, wideband antenna. 0018-926X (c) He is currently serving as theSecretary of IEEE AP-S. His research interests include design of small and planar antennas for various wireless communication systems, analysis and design of frequency-selective structures and absorbers, hybrid numerical techniques for modeling RF/microwave components and antennas. He has authored or co-authored more than 130 journal papers and presented another 120 conference papers. Zhuozhu Chen (S'13) was born in Hunan province, China. He received the B.Eng. degree and the M.S. degree in electronic engineering from Beijing Institute of Technology, China, in 2010 and 2013, respectively. He is currently working toward the Ph.D. degree in electrical and electronic engineering at Nanyang Technological University, Singapore.His research interests include design of RF/microwave antennas and circuit.

Surface Waves Propagating on Grounded Anisotropic Dielectric Slab

“…The solution of suppressing surface waves on grounded anisotropic slab was explored in [17]. Furthermore, investigations were also focused on the radiation conditions of surface wave on grounded dielectric slabs, which have been employed for designing wideband, low-profile, as well as high gain antennas [18][19][20].…”

“…(i) It is revealed that no pure TM or TE mode exists on the grounded infinitely large slab if the field is non-uniformly distributed along the direction orthogonal to the propagation direction; (ii) Closed-form analytical expressions are derived to theoretically study the characteristics of quasi-TM and quasi-TE surface modes on the finite-width grounded anisotropic grounded slab. It is found that surface waves propagate away from the longitudinal direction of the finite-width slab with some certain angle, and the angle decreases as the slab width increases; (iii) Different from the existing analyses of surface waves whose fields distribute uniformly along the transverse direction of the infinitely large slab, our method takes into account the variations of the fields distributed on the transverse direction of the grounded anisotropic slab, which has a more practical relevance and can provide a more accurate solution for engineering applications such as designing wideband and high gain antennas based on grounded dielectric slabs [9,[18][19][20]. It is worth mentioning that our method is also suitable for grounded isotropic dielectric slab.…”

Compact Wideband and Low-Profile Antenna Mountable on Large Metallic Surfaces

“…In the recent years, different techniques have been utilized to propose wideband flush-mounted antennas with low profile and end-fire radiation [2]- [16]. Microstrip Yagi array antennas have been first introduced in [2] and further developed in [3]- [6] with the advantages of end-fire radiation, low profile and low cost.…”

“…However, the antenna feeding geometry in [13] is complicated and the impedance bandwidth is only matched to VSWR < 2.5 instead of 2. Surface wave antennas have been studied in [14]- [16]. In [16], a surface wave antenna with a very low profile of 0.061 λL has been reported.…”

Planar Ultrathin Small Beam-Switching Antenna

“…A three-element patch array based ESPAR is proposed in [17], which achieves continuous scanning range of -15 o to 15 o in the elevation plane. Nevertheless, end-fire beams are preferable in some applications such as unmanned aerial vehicle (UAV) and wireless communications for azimuth signal coverage [18].…”