Microwave realization of multiresonant metasurfaces for achromatic pulse delay

Abstract We propose a microwave realization of a metasurface that can delay broadband pulses without distortion in reflection. In order to obtain large and broadband pulse delay, we harness the synergetic phase delay of five sharply-resonant meta-atoms. More specifically, three electric-LC and two split ring resonators, supporting electric and magnetic dipole resonances, respectively, are combined in a subwavelength unit cell. The resonances are spectrally interleaved and specifically designed to provide a spectrally-constant reflection amplitude and group delay according to the prescription in [ACS Photonics 5, 1101, 2018]. The designed metasurface is electrically ultrathin (λ0/19), since it relies on resonant phase delay exclusively, instead of phase accumulation via propagation. We show delay of 700-MHz Gaussian pulses centred at 11 GHz by 1.9 ns, corresponding to approximately 21 carrier cycles. Our results highlight the practical potential of metasurfaces for broadband dispersion control applications.

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Dual-Band High Q-Factor Complementary Split-Ring Resonators Using Substrate Integrated Waveguide Method and Their Applications

Journal of Electrical and Computer Engineering ◽

10.1155/2019/6287970 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11

Author(s):

Mehdi Hamidkhani ◽

Rasool Sadeghi ◽

Mohamadreza Karimi

Keyword(s):

Phase Noise ◽

Group Delay ◽

Cavity Resonator ◽

Practical Method ◽

Ring Resonators ◽

Dual Band ◽

High Group ◽

Split Ring ◽

Split Ring Resonators ◽

Low Phase Noise

In modern microwave telecommunication systems, especially in low phase noise oscillators, there is a need for resonators with low insertion losses and high Q-factor. More specifically, it is of high interest to design resonators with high group delay. In this paper, three novel dual-band complementary split-ring resonators (CSRRs) featuring high group delay etched on the waveguide surface by using substrate integrated waveguides are investigated and proposed. They are designed for a frequency range of 4.5–5.5 GHz. Group delay rates for the first, second, and third resonators were approximated as much as 23 ns, 293 ns, and 90 ns, respectively. We also proposed a new practical method to develop a wide tuning range SIW CSRR cavity resonator with a small tuning voltage in the second resonator, which leads to about 19% and 1% of tuning frequency band in the first and second bands, respectively. Finally, some of their applications in the design of filter, diplexer, and low phase noise oscillator will be investigated.

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Fully Metallic Flat Lens Based on Locally Twist-Symmetric Array of Complementary Split-Ring Resonators

Symmetry ◽

10.3390/sym11040581 ◽

2019 ◽

Vol 11 (4) ◽

pp. 581 ◽

Cited By ~ 5

Author(s):

Oskar Dahlberg ◽

Guido Valerio ◽

Oscar Quevedo-Teruel

Keyword(s):

Communication Networks ◽

Focal Point ◽

Spherical Wave ◽

Unit Cell ◽

Phase Delay ◽

Ring Resonators ◽

Wireless Communication Networks ◽

Split Ring ◽

Split Ring Resonators ◽

Unit Cells

In this article, we demonstrate how twist symmetries can be employed in the design of flat lenses. A lens design is proposed, consisting of 13 perforated metallic sheets separated by an air gap. The perforation in the metal is a two-dimensional array of complementary split-ring resonators. In this specific design, the twist symmetry is local, as it is only applied to the unit cell of the array. Moreover, the twist symmetry is an approximation, as it is only applied to part of the unit cell. First, we demonstrate that, by varying the order of twist symmetry, the phase delay experienced by a wave propagating through the array can be accurately controlled. Secondly, a lens is designed by tailoring the unit cells throughout the aperture of the lens in order to obtain the desired phase delay. Simulation and measurement results demonstrate that the lens successfully transforms a spherical wave emanating from the focal point into a plane wave at the opposite side of the lens. The demonstrated concepts find application in future wireless communication networks where fully-metallic directive antennas are desired.

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Tunable group delay in a doubly resonant metasurface composed of two dissimilar split-ring resonators

Journal of the Optical Society of America B ◽

10.1364/josab.36.002694 ◽

2019 ◽

Vol 36 (10) ◽

pp. 2694 ◽

Cited By ~ 1

Author(s):

Yasuhiro Tamayama ◽

Yutaro Kida

Keyword(s):

Group Delay ◽

Ring Resonators ◽

Split Ring ◽

Split Ring Resonators

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A Planar UWB Antenna with Dual Band Rejection Capability Using Double Rotated ESRRs

Advanced Electromagnetics ◽

10.7716/aem.v7i1.589 ◽

2018 ◽

Vol 7 (1) ◽

pp. 19-24 ◽

Cited By ~ 1

Author(s):

A. S. Elkorany ◽

G. T. Ahmed ◽

D. A. Saleeb

Keyword(s):

Return Loss ◽

Group Delay ◽

Ultra Wideband ◽

Ring Resonators ◽

Dual Band ◽

Uwb Antenna ◽

Split Ring ◽

Wireless Applications ◽

Different Dimensions ◽

Good Agreement

In this paper, CPW-Fed ultra wideband (UWB) planar monopole antenna (PMA) loaded by double elliptical split ring resonators (ESRRs) for double band-notch characteristics is introduced and examined. Two different ESRRs with different dimensions are printed in the antenna backside to notch two different frequencies. The ESRRs are also rotated and the corresponding return loss effect is examined. Different notch frequencies can be obtained by varying the ESRRs, dimensions. Two single SRRs are used to notch two frequencies instead of using dual SRR pairs. Two notch frequencies at 5.2 GHz and 6.9 GHz has been obtained to notch WLAN and C-band wireless applications, respectively. A directive radiation pattern in E-plane and omnidirectional radiation patterns in the H-plane could be observed. Also the gain is suppressed in the notch frequencies. The group delay is nearly stable in the UWB frequency range, except at the notch frequencies, which is distorted sharply. So, the proposed antenna is a good candidate for the modern UWB systems. Finite element method FEM and finite integration technique FIT are used to simulate the proposed structures through the usage of Ansys HFSS and CST MWS. Very good agreement between both results has been obtained.

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