Left-handed Transmission Line Research Articles

Rogue and solitary waves of a system of coupled nonlinear Schrödinger equations in a left-handed transmission line with second-neighbors coupling

The effects of the second-order neighbor interaction have been effective on the coherent localized waves and modulation instability spectrum. A coupled nonlinear Schrödinger equation is derived in the nonlinear left-handed electrical lattice, and the linear stability is used to formulate the modulation instability spectrum expression. Unstable modes are displayed to show symmetric lobes and increasing bandwidths under the influence of the neighbor coupling. The Benjamin-Feir instability has prospered in the network, and for weak perturbed wave numbers, the unstable modes increase. The numerical simulation is used to develop localized waves, including rogue waves with one crest and two humps, Akhmediev breathers, and other modulated structures. We notice that, for strong values of the perturbed wave number, an exponential growth of the continuous wave arises to confirm the fact that the nonlinear left-handed electrical lattice with coupling strength is opened to coherent localized waves. The long-lived nature of the obtained structures has also been demonstrated for specific times of propagation.

Design and analysis of SRR based metamaterial loaded circular patch multiband antenna for satellite applications

Satellite communication has reached a turning point in transmitting data quickly and receiving signals clearly in faraway places. This paper presents a metamaterial-based antenna for distant and military applications that overcomes restrictions and performs unmatched. This project explores metamaterials to create a unique antenna. Expect to be astounded by its power to bend electromagnetic waves, miniaturize, and change our relationship with the universe. The feeding mechanism of this antenna is a modified co-planar waveguide. At 5.6 GHz, the proposed antenna unit cell measures 0.076λ0×0.2λ0, making it small thanks to its MTM characteristic. CP radiation is made when two orthogonally polarized modes are stimulated at the same time and two composite right- and left-handed transmission line unit cells are placed orthogonally. Reduced size, increased bandwidth, and improved Learn how this discovery opens new doors for high-resolution photography, broadband internet, and space exploration. One nanostructure that makes up a metamaterial is the Split Ring Resonator (SRR). SRR dimensions must be smaller than the resonance wavelength, making them crucial for near-infrared and optical responses. This effort examined nanoscale SRR characteristics in the infrared and visible ranges. SRRs composed of aluminum (Al) and gold (Au) were produced on silicon and silica substrates using electron beam lithography (EBL). The proposed structure consists of a microstrip-line-supplied SRR, a parasitic patch that is perpendicular to the ground plane, and two via holes connected by two split rings that feed the patch indirectly. Choosing the right material parameter for all such antennas depends on the planned structure. Fabrication and testing of the antenna matched simulations. Dimensions: 23.7 mm × 16.2 mm × 1.6 mm; substrate dielectric constant: 4.4. Experimental data are detailed and compared to analytical calculations. Simulation results show that metamaterials have negative permittivity and permeability in a certain frequency range, which can be predicted by an analytical method. Simulations indicated eight BRS, WiMAX, radar, and mobile phone resonance frequencies. Radiation is dipole-like in the omnidirectional in the H-plane and E-plane. 10 dB return loss and 3 dB axial ratio bandwidths are 38.6.7% and 8.1%, respectively.

Metamaterial Inspired Varactor-Tuned Antenna with Frequency Reconfigurability and Pattern Diversity.

A metamaterial-inspired varactor-tuned antenna with frequency reconfigurability and pattern diversity is designed. Two different versions of a reconfigurable structure are integrated into a single antenna to excite two different orthogonal patterns, which realizes pattern diversity for MIMO applications. The outer annular Composite Right-/Left-Handed Transmission Line (CRLH-TL) works at the 1 mode and provides a broadside pattern, and the inner circular radiator loaded with split ring resonators (SRR) operates at the 0 mode and radiates an omnidirectional pattern, which realizes pattern diversity. By using surface-mounted varactors, the operating frequencies for the two radiation patterns can be tuned over a wide frequency range, from 1.7 GHz to 2.2 GHz, covering the 1.71-2.17 GHz LTE band, and a low mutual coupling between the two radiators is achieved. The antenna has also been prototyped. The measured results are in good agreement with the simulation results, verifying the proposed concept. The dual-mode MIMO system equipped with the proposed antenna elements is discussed within the context of a 3-D channel model, and it shows a superior array compactness and spectral efficiency (SE) performance compared to scenarios with single-mode elements.

Ka-Band Miniaturized 90 nm Complementary Metal Oxide Semiconductor Wideband Rat-Race Coupler Using Left-Handed and Right-Handed Transmission Lines

The traditional rat-race coupler comprises a quarter-wavelength transmission line and a three-quarter-wavelength transmission line. In this design, the slow-wave structure transmission line is employed to replace the conventional quarter-wavelength transmission line, and the three-quarter-wavelength transmission line is substituted with the left-handed transmission line. By using the TSMC CMOS 90 nm fabrication process, a circuit is created with a chip size of 300 μm × 200 μm, corresponding to the electrical size at 39 GHz of 0.039λ0 × 0.026λ0. The measured results demonstrate that the operating bandwidth is 35 to 43 GHz, with an amplitude imbalance of around 0 dB, a phase error within 1°, a return loss of less than 26 dB, and an isolation better than 40 dB.

Dual-band miniaturized composite right left handed transmission line ZOR antenna for microwave communication with machine learning approach

This article presents a dual-band miniaturized Composite Right-Left-Handed Transmission Line (CRLH-TL) in an open-ended terminal, employing the Machine Learning (ML) technique. The CRLH-TL antenna is designed on the FR4 epoxy substrate. The substrate size is 0.31λ0 × 0.09 λ0, where λ0 is the free space wavelength. The proposed antenna offers dual-band functionality with resonant frequencies at 2.49 GHz and 5.33 GHz. The measured dual-band impedance bandwidths are 14.46 % and 14.74 %, with gains of 0.85 dB and 1.67 dB, and radiation efficiencies of 91.78 % and 95.45 % obtained at resonating frequencies of 2.49 GHz and 5.33 GHz, respectively. The proposed antenna also offers bipolar-type radiation patterns in the E-plane, and omnidirectional radiation patterns in the H-plane, along with compactness and constant gain. Several ML methods, including Random Forest (RF), Decision Tree (DT), K-Nearest Neighbour (KNN), Extreme Gradient Boosting (XGB), and Artificial Neural Network (ANN), are used to optimize the antenna. Compared to other ML algorithms, RF ML techniques estimate reflection coefficient S11 with an accuracy of above 98 %. The proposed antenna is utilized in WLAN (5.15–5.35, 5.47–5.725 GHz) and Wi-MAX (5.2–5.8 GHz) microwave applications.

Impact of viscothermal loss on modulation instability and rogue waves in left-handed nonlinear diffractive acoustic transmission line metamaterials

In this study, the transmission line approach is used to describe the studied acoustic metamaterial model. Through Kirchoff’s pressure and volume-velocity laws and using multiple scales method, nonlinear coupled Schrödinger equations are obtained. Then, the amplitude disturbance method is applied to these equations to obtain and plot the modulational instability gain curves. Analytically, the impact of viscothermal loss on the modulational instability gain is studied. The similarity technique is used to derive integrable Manakov’s equations. First and second-order rational rogue wavelike solutions of coupled nonlinear Schrödinger are deduced. The results indicate that the modulational instability gain and Rogue wave intensities depend on the viscothermal parameter. This parameter can be considered in the design of nonlinear acoustic metamaterials to minimize the damage caused by the dynamics of freak waves.

Compact and Broadband-Balanced Amplifier for a Monolithic Microwave Integrated Circuit Using Lumped Elements Only

A flat phase difference across a broad bandwidth is achieved by appropriately combining the positive and negative phase propagation of right-handed (RH) and left-handed (LH) transmission lines (TLs), respectively. Employment of lumped elements provides easy realization of both TLs with the desired frequency passband, characteristic impedance, and phase propagation. The proposed quadrature power divider (QPD) was fabricated in a compact size by only using lumped elements instead of general TLs with a large area and a narrow bandwidth. The fabricated QPD maintains a flat phase difference of 90° ± 8.7° over a frequency range of 1.19–2.96 GHz while its circuit size is 0.036 λ g 2 . Owing to drastic size reduction of the QPD, the proposed balanced amplifier (BA) also could be realized with an extremely compact size of 0.044 λ g 2 and broad bandwidth unlike in other BAs reported in the literature and maintains a return loss of less than −10 dB at each port over the bandwidth of the QPD.

Multi-soliton interactions, comb behavior, strange mixed breathers and other exotic rogue waves generated in a nonlinear left-handed transmission line

We establish a cubic–quintic-nonlinear Schrödinger equation (CQNLSE) including cubic- and quintic-nonlinearities, second-, third- and fourth-order dispersions in a left-handed nonlinear transmission line. We use the collective coordinates’ theory and the Gaussian Ansatz function with six coordinates to improve the comprehension of the system. Besides, the following innovations have been found when linear and nonlinear effects interact. (i) Some phenomena have emerged such as comb behavior, fragmentation of waves and wall of waves. (ii) Some solutions have also emerged such as the dark soliton, multi-peak waves, Kuznetsov–Ma breathers, periodical and non periodical mixed wave trains, Sasa–Satsuma waves, Peregrine waves, and crossed solitons. Otherwise, the internal perturbations leading to all aforementioned exotic rogue events are well studied in detail.

Millimeter-wave low-loss on-chip metamaterial for 5G communication based on non-periodic composite right-/left-handed transmission line

This Letter reports a millimeter-wave low-loss on-chip metamaterial based on a concept of a non-periodic composite right-/left-handed (CRLH) transmission line (TL). Compared with a classic periodic unit cell, a non-periodic CRLH TL is proposed to obtain higher transmittance and better reflectivity. First, based on the CRLH TL theory, the LC values of the periodic transmission line were calculated. Second, Ti factors were derived using Chebyshev low-pass filter prototypes and the bandpass transformation theory. Third, these values were then used to calculate the factors of the non-periodic structure, which was eventually implemented using lumped elements. By analyzing the dispersion property, the proposed non-periodic CRLH metamaterial features both right-handed (forward wave) and left-handed (backward wave) propagating modes, which accounts for its wide bandwidth. For demonstration, a gallium arsenide-based integrated passive device process is adopted. As its main advantages, the fabricated metamaterial shows a high and flat transmission with minimum insertion loss of 0.68 dB at 30.2 GHz, and a low reflectivity better than −10 dB from 14 to 51 GHz of which the fraction bandwidth is over 120%.

Peregrination, layers’ and multi-peaks’ generation induced by cubic-quintic-saturable nonlinearities and higher-order dispersive effects in a system of coupled nonlinear left-handed transmission lines

Peregrination, layers’ and multi-peaks’ generation induced by cubic-quintic-saturable nonlinearities and higher-order dispersive effects in a system of coupled nonlinear left-handed transmission lines

Spectral stability and dynamics of solitary waves in a coupled nonlinear left-handed transmission line

Spectral stability and dynamics of solitary waves in a coupled nonlinear left-handed transmission line

A Miniaturized Dual-Band Short-Ended ZOR Antenna with Backed Ground Plane for Improved Bandwidth and Radiation Efficiency

This paper presents a miniaturized planar dual-band short-ended metamaterial antenna with the backed ground plane to improve antenna bandwidths and radiation characteristics. The proposed dual-band metamaterial (MTM) antenna has been made up of the composite right- or left-handed transmission line (CRLH-TL) concept. Here, the backed ground plane has been employed to generate an extra coupling capacitance (CC), which shifts the ZOR frequency in the lower band while also improving ZOR matching and increasing the impedance bandwidth of the higher-order mode. In this proposed MTM antenna, interdigital capacitance (IDC) has been used in place of a simple series gap, which shifts the higher-order impedance bandwidth into a lower frequency band for second-band Wi-MAX applications (3.3–3.7 GHz). The proposed antenna offers a short-ended MTM, and hence the ZOR frequency is controlled by a series of LC lumped parameters. The proposed antenna offers dual-band behavior with measured −10 dB impedance bandwidths of 5.55% and 41.57% at centered frequencies of 2.70 GHz and 4.33 GHz, respectively. The overall electrical size of the designed antenna is 0.225λ0 × 0.144λ0 × 0.0144λ0 at ZOR (f0 = 2.70 GHz), where λ0 is the free space wavelength; therefore, it is applicable for different Wi-MAX application bands (2.5–2.7 GHz/3.3–3.8 GHz). Furthermore, the proposed dual-band MTM antenna provides compactness, low loss, stable gain, and radiation efficiency, and also offers omnidirectional radiation patterns in the E-plane and dipolar type radiation patterns in the H-plane, respectively.

A Design of Metamaterial Inspired Resonator for Multifrequency Fluidic Sensors

This letter presents a multifrequency planar resonator fed by coplanar waveguide (CPW) for the determination of dispersive fluidic materials. By employing composite right-/left-handed transmission line (CRLH TL) in the resonator, the characteristic of multiresonance has been achieved in a compact size (0.17 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times \,\,0.15\lambda _{0}^{2}$ </tex-math></inline-formula> ), which can enhance the sensitivity of the resonator as a sensor at multiple frequencies. The substrate is integrated with a fluidic container made of polydimethylsiloxane (PDMS). The optimum design operates at 2.28, 2.95, and 10.6 GHz to cover both the lower and the higher frequency bands. Also, it shows very good sensitivity (0.98, 0.7, and 0.67) at each resonant frequency. Deionized water at different temperatures and water–ethanol mixtures are used to verify the performance of the sensor in multiple frequency bands. The advantages of the proposed design, including compact size, multifrequency resonances, and high sensitivity, make it a competitive solution for detecting biological samples with similar electromagnetic properties in a single-frequency band.

Some Important Points of the Josephson Effect via Two Superconductors in Complex Bases

In this paper, we study the extraction of some analytical solutions to the nonlinear perturbed sine-Gordon equation with the long Josephson junction properties. The model studied was formed to observe the long Josephson junction properties separated by two superconductors. Moreover, it is also used to explain the Josephson effect arising in the highly nonlinear nature of the Josephson junctions. This provides the shunt inductances to realize a Josephson left-handed transmission line. A powerful scheme is used to extract the complex function solutions. These complex results are used to explain deeper properties of Josephson effects in the frame of impedance. Various simulations of solutions obtained in this paper are also reported.

CRLH-TL Based Reconfigurable Antennas With Multiple Parameter Reconfigurability

In this communication, two composite right-/left-handed transmission line (CRLH-TL)-based reconfigurable antennas with multiple-parameter reconfiguration capability have been presented. In antenna I, the polarization is switched between circular polarization and linear polarization. In antenna II, a split-ring resonator (SRR) is introduced that is connected with the ground through another p-i-n diode D2. In the D2 OFF-state, the metamaterial behavior of the SRR establishes. Due to negative permeability at the frequency of operation, it produces magnetic coupling with the antenna and the antenna starts radiating at a new band (5.2 GHz), forming dual-band characteristics with circular polarization. Antenna II is capable of providing band/frequency and polarization/band, frequency, and polarization reconfiguration using different ON/OFF combination states of diodes D1 and D2. The antennas are suitable for 2.4/5.2 GHz WLAN and 3.5/3.6 GHz WiMAX applications.

Backward- and forward-wave soliton coexistence due to second-neighbor coupling in a left-handed transmission line

We study analytically and numerically the impact of the second-neighbor interactions on the propagation of an initial wave-packet through a coupled nonlinear left-handed transmission line. We start with a detailed analysis of the dispersion curve and group velocity. We then use the quasi-discrete approximation with respect to long wavelength transverse perturbations to reduce the nonlinear discrete model of the lattice to a nonlinear Schrödinger equation. A detailed analysis of the product of the group velocity dispersion (P) and the nonlinear term (Q) is presented with respect to the relevant parameters of the system. Here we see the important role of the second-neighbor coupling, which makes the dispersion curve non-monotonic. Thus, for a given frequency, the group velocity can be both positive and negative, while for each choice the product, PQ, can be either positive or negative. Our numerical results confirm that for sufficiently strong second-neighbor coupling, bright backward-wave pulses and dark solitons can coexist at a common frequency, and these travel in opposite directions through the lattice.

Low loss triplexer with wide stopband using CRLH-TL for WLAN/WiMAX/5G Wi-Fi applications

ABSTRACT This paper reports the design and development of a planar triplexer for WLAN/WiMAX/5G Wi-Fi applications based on a composite right-/left-handed transmission line (CRLH-TL) with low passband insertion loss, high channel isolation, wide stopband and minimal fabrication complexity. Even- and odd-mode methods are used to extract resonant properties of the globe-shaped open stub loaded stepped impedance resonator (GSOSL-SIR). The transmission line model of the GSOSL-SIR is analyzed and based on that; three bandpass filters are designed at 2.4/3.5/5.5 GHz. The equivalent LC circuit model for GSOSL-SIR-based CRLH-TL is provided with all lumped parameters fully defined. Finally, Triplexer is proposed by connecting all the three bandpass filters where each channel shows measured center frequency of 2.4/3.48/5.52 GHz with 3 dB fractional bandwidth of 22.08/22.19/16.3%. The proposed triplexer achieves high channel isolation (>30 dB) and low in-band insertion losses (1.1/0.87/1.3 dB) for the three filter channels. Additionally, the triplexer has measured 20 dB rejection levels from 6.5 GHz to 14.64 GHz and 10 dB rejection levels from 6.22 GHz to 19.85 GHz. The observed concordance between measured, electromagnetic simulated and equivalent LC circuit simulated results supports the utility of the design method.

Investigation of Leaky-Wave Antenna With Stable Wide Beam-Scanning Characteristic

In this article, a compact magnetic dipole (MD) composite right-/left-handed transmission line (CRLH-TL) leaky-wave antenna (LWA) is proposed, which is periodically loaded with rectangular gaps and short stubs. Then, in light of the dielectric resonator with a high dielectric constant, low loss tangent, and good radiation performance, we further add an alumina ceramic block (ACB) to stack on the gap in each CRLH-TL LWA unit cell for forming the MD, and thus, wide beam-scanning range and compactness are achieved. To validate this design, a traditional uniform CRLH-TL LWA is investigated in detail. The results of S-parameters, electrical field distribution, and radiation properties illuminate the effects of introducing the ACB, such as impendence matching improvement and high radiation efficiency. Furthermore, to verify the flexible control of the balanced condition and the attenuation constant by changing the microstrip gap width and the ACB thickness predicted in the circuit model analysis, a nonuniform CRLH-TL LWA with quasi-constant amplitude is fabricated. Experimental results demonstrate a higher antenna gain and the stability of wide beam-scanning range under the condition of a compact design.

Two-Degree-of-Freedom Control of Field Distribution on Nonreciprocal Metamaterial-Line Resonators and Its Applications to Polarization-Plane-Rotation and Beam- Scanning Leaky-Wave Antennas

Two-degree-of-freedom control of field distribution on the pseudotraveling wave resonator using nonreciprocal metamaterial lines is demonstrated for the first time. Dynamic control of current distribution on the resonator is given based on circuit theory. We employed a normally magnetized ferrite microstrip line-based composite right-/left-handed (CRLH) transmission line as a metamaterial with variable phase-shifting nonreciprocity. Numerical simulation results show that the phase gradient of the fields along the resonator is controlled by the applied dc magnetic field to the ferrite. By changing the reflection coefficients of two reflectors inserted at both ends of the CRLH line section, current distribution along series and shunt branches of the unit cell is continuously and drastically changed under the resonance. The variable field distribution was implemented to polarization-plane-rotation and beam-scanning leaky-wave antennas. The experimental demonstration verifies our basic concept and shows the performance of the prototype antenna with a beam scanning angle of 20° and a continuous rotation angle of polarization plane by ±70° at the fixed frequency.

Simulation-Driven Triple-Tuned Array for 1H, 31P and 23Na Using Composite Right- and Left-Handed Transmission Line for Rat Brain at 9.4T MRI

The use of ultrahigh-field-strength magnetic resonance imaging (MRI), such as 9.4T, is able to acquire multi-nuclear imaging with better image quality than lower field strengths. In particular the acquisition of sodium ( <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">23</sup> Na) or phosphorus ( <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">31</sup> P) images could benefit with higher signal-to-noise ratio (SNR). The design of radiofrequency RF coils is required to achieve a uniform field and to operate at the corresponding frequency. The general method to make multiple frequency coils has the drawback of using multilayers or reducing the size of the coils, which impose restriction on the utilization of space. For the conventional multiple frequency array, the design for the coil size imposes a challenge for the optimization of SNR and field intensity. In addition, the use of multiple coils increases the coupling between each coil. To circumvent these problems, we propose the use of composite right-left handed (CRLH) transmission lines (TL), which are able to resonate to multiple frequencies. This work demonstrates a design of an array of four channels, in which each channel consists of a single CRLH element capable to resonate at three frequencies corresponding to <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> H at 400 MHz, <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">31</sup> P at 162 MHz, and <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">23</sup> Na at 105 MHz. The design was demonstrated with electromagnetic (EM) simulations and applied for rat brain for use in a 9.4T MRI system.