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Application of Split Ring Resonators to Microwave Circuit Design
Published in Filippo Capolino, Applications of Metamaterials, 2017
Ferran Martín, Ricardo Marqués
This chapter is devoted to the applications of split ring resonators (SRRs) [1] and their complementary counterparts (complementary split ring resonators, CSRRs) [2] to the design of microwave circuits and devices. As will be seen, device miniaturization and the possibility to synthesize microwave components with improved performance and/or novel functionalities will result. The chapter begins with Section 9.1 where the two alternative approaches to the synthesis of metamaterial transmission lines are pointed out. Section 9.2 highlights the applications and analysis of the key aspects that make SRRs and CSRRs useful particles for microwave device design. The most interesting application of SRRs and CSRRs is, due to its resonant nature, in the field of filters. Nevertheless, other microwave devices, such as impedance inverters, power dividers and directional couplers, among others, can also be envisaged. In Section 9.3, the varactor-loaded split ring resonator (VLSRR) is introduced as a tunable component of practical use for the design of reconfigurable components such as notch filters and resonators. Finally, other applications of SRRs and CSRRs are discussed in Section 9.4.
Modeling of Optical Metamaterials Using the FDTD Method
Published in Sarhan M. Musa, Computational Nanotechnology Using Finite Difference Time Domain, 2017
The coordinate transformation technique used in [8,14] has also been applied to the design of magnifying perfect and super lenses [15], electromagnetic field rotators [16], the reflectionless complex media for shifting and splitting optical beams [17], and conformal antennas [18]. The experimental demonstration of a simplified cloak consisting of split-ring resonators (SRRs) has been reported at microwave frequencies [19]. For the optical frequency range, the cloak can be constructed by embedding silver wires in a dielectric medium [10], or using a gold-dielectric concentric layered structure [20,21].
Optical Properties of Solids
Published in Elaine A. Moore, Lesley E. Smart, Solid State Chemistry, 2020
Elaine A. Moore, Lesley E. Smart
Both these methods depend on engineering a material with a refractive index varying in a precise way. Metamaterials have the advantage that they can be tuned to do this by varying the physical structure of a material. The first example of a cloak of invisibility, reported in 2006, used an array of metallic ‘split ring’ resonators. This device shielded a copper cylinder at a range of microwave frequencies. Researchers at the University of Texas have demonstrated cloaks to suppress scattering at microwave frequencies in all directions from a cylinder.
A Monopole Antenna with Offset-fed Microstrip Line for Wireless Application
Published in IETE Journal of Research, 2019
R. Shantha Selvakumari, A. Swetha Ranjani
The development of wireless technology leads to the need of miniaturized antenna of required bandwidth. To meet the requirement such as low cost, size, weight, ease of installation and performance for commercial applications and military application, the low profile antennas [1] are on huge demand. The above requirements are met or achieved by microstrip antennas [2]. These antennas are of patch or printed types and are inexpensive to manufacture. It consists of a metallic patch mounted on a larger metal sheet is called ground plane. The design configures rations such as sizes and type of substrates will depend on the desired frequency of operation and its radiation performances. Monopole antennas for wireless devices are mainly constructed using printed technology. Fundamentally, the small antenna design is based on the configuration of a monopole at different resonances monopole strips or arms create different current paths [3]. Excitation of multiple resonant frequencies at their fundamental mode is achieved by monopole antenna. Interference can be reduced greatly by designing Split ring resonator and Complementary split ring resonator. The split ring resonator is formed of enclosed loops pair with slit at the two ends. Split ring resonator exhibits a quasi static resonant nature due to this it exhibits a wavelength of resonant frequency less than or smaller than its size. Split ring resonator exhibits a highly directional radiation pattern.
Signal integrity analysis on a microstrip ultra-wideband coupled-line coupler
Published in International Journal of Electronics, 2019
Saffrine Kingsly, Sangeetha Velan, Malathi Kanagasabai, Sangeetha Subbaraj, Yogeshwari Panneer Selvam, Bhuvaneswari Balasubramaniyan
A double-split solitary ring was deployed to improve the impedance performance of the entire band. Addition of number of splits in a split ring resonator acts like capacitance in series which lowers the capacitance of the device (Penciu et al., 2008). The dual of this SRR model can be obtained by replacing the series capacitance with shunt inductance (Baena et al., 2005). Since the inductors are connected parallel, the resonant frequency increases as given by ɷ = 1/√LC. The equivalent circuit of the double-split solitary ring can be modelled as a capacitor for the ring slot and two inductance for the double-split in the ring as shown in Figure 4. This also improves the coupling at higher frequencies. Coupling at the X-band satellite downlink range is reduced since it is mainly used for military applications where the signal transmitted should be of good quality and minimum error. It can also be increased by increasing the number of double-split solitary rings. Tapering the feed on one-end increases the capacitance at higher frequencies and so the proposed coupled-line coupler operates for the entire UWB.