Bandwidth and gain‐enhanced composite right/left‐handed antenna for ultra‐wideband applications

Abstract

A coplanar waveguide-fed metamaterial antenna is presented for ultrawideband (UWB) applications. The proposed antenna is designed with single unit-cell composite right/left-handed transmission line (CRLH-TL) loaded with a split-ring resonator (SRR). The UWB characteristic is obtained by merging the zeroth-order resonance of CRLH-TL with two additional resonances due to the ground plane and SRR respectively. Subsequently, a partial reactive impedance surface is embedded on the rear side of the proposed antenna to enhance the realized gain without affecting the UWB response. The overall size of the antenna is 0.241λ o x 0.267λ o x 0.013λ o (28.8 x 32 x 1.6 mm 3 ), where λ o is the free space wavelength at 2.51 GHz. The measured results indicate -10 dB fractional bandwidth of 139.19% (2.51-14 GHz) with realized gains of 2.3, 4.6, and 6 dBi at the resonant frequencies 4, 7.84, and 10.29 GHz respectively. The measured peak realized gain is 6.6 dBi at 10.6 GHz. The radiation efficiency is above 63.85% for the entire UWB range with a peak value of 86.84%. A fairly stable group delay with variation within 1 ns is obtained throughout the operating frequency band. A good agreement has been observed between the measured and simulated results. K E Y W O R D Scomposite right/left-handed (CRLH), coplanar waveguide, gain enhancement, ultra-wideband (UWB) antenna, zeroth-order resonance (ZOR)

Substrate analysis on the wideband, high gain flower-shaped MIMO antenna

“…A patch antenna with a tapered patch and ground plane offers wide-band characteristics [7]. The usage of CRLH-TL (Composite Right/Left-Handed Transmission Line)along with SRR(Split Ring Resonator) brings the wideband characteristics [8]. The addition of a reflective focusingmetasurface with a slotted patch antenna enhances the gain [9].…”

Planar Multi Notch Band Antenna In-band Gain Enhanced by Epsilon-near-zero Non-absorptive Metasurface

“…Recent methods like Fabry-Perot cavity antenna [4][5][6][7] and frequency selective surface (FSS) [8][9][10][11] can overcome this complexity, but they do not provide broadband gain enhancement. The latest solution for obtaining the broadband gain is to utilise artificial materials called metamaterials [12][13][14][15]. A periodic planar arrangement of metamaterial unit cells called metasurface can control electromagnetic properties like reflection, transmission, and absorption.…”

A metamaterial‐based compact multiple‐input multiple‐output antenna with pattern diversity

“…They possess several intriguing electromagnetic properties that do not exist in conventional TLs, which allow antennas to work not only in positive modes, but also in negative modes and even the zeroth‐order resonant (ZOR) mode (0 mode). The applications of them have facilitated the design of multiband antennas, 12,13 wideband antennas, 14,15 compact antennas, 16 ZOR antennas, 17 circular polarized antennas, 18,19 leaky‐wave antennas, 20 and reconfigurable antennas 11 . The use of CRLH‐TL can also be beneficial to achieve pattern diversity antennas, since it has the ability to achieve both broadside and omnidirectional patterns by working with the different modes.…”