Parul Dawar

Bandwidth enhancement of RMPA using ENG metamaterials at THz

Left handed materials which have both negative permittivity and permeability, have been the area of potential research over a decade. As the technology advances, metamaterials have capability to vastly impact the field of antennas. This paper elucidates antenna parameter optimization using metamaterial (MTM) embedded in antenna substrate at high frequency (THz). Ansoft HFSS has been used to design and analyse the RMPA (rectangular microstrip patch antenna) with design frequency 227 THz and operating range of 215THz to 239THz having RT duroid (εr=2.33) as substrate material Three metamaterials (MTMs), single split, double split and interdigitated, having negative permittivity (Epsilon negative group i.e. ENG) in the given frequency range are embedded in the substrate. Upon incorporation bandwidth widens to around 19% and VSWR improves by approx 5%.

Tunability of Triangular SRR and Wire Strip (TSRR-WS) Metamaterial at THz

This paper adumbrates a novel tunable metamaterial consisting of triangular split ring resonator (TSRR) and wire strip (WS) at THz frequency. Ansoft high frequency structure simulator (HFSS) has been used to design and analyse the metamaterial having Rogers RT/duroid 5870 ( = 2.33) and FR4 ( = 4.4) as substrate material. Nicolson Ross Weir (NRW) method has been used to retrieve the material parameters from transmission and reflection coefficient. 4% maximization has been obtained in the location of the negative region (or resonance frequency for permeability) by using FR4 with 0.75 μm instead of 1.25 μm as substrate thickness. In addition, 18% minimization has been achieved by using FR4 with 0.25 μm instead of RT/duroid 5870 substrate with the same thickness. Tunability has been proved by showing dependence of resonant frequency over the substrate thickness and substrate material.

UWB and directive E-shaped metamaterial patch antenna

Left-handed materials, which have both negative permittivity and permeability, have been the area of potential research over a decade. This paper elucidates the design of a double-negative group (DNG) THz metamaterial, namely, E-shaped, having negative refraction ranging from 34.5 to 37.5 THz. Rectangular microstrip patch antenna (RMPA) with microstrip feed has been designed using Ansoft HFSS with RT Duroid (ϵr = 2.33) as substrate and having the same frequency range as that of the metamaterials negative region. Upon incorporation of proposed metamaterials array inside the antenna substrate, bandwidth of antenna increases by 4 THz and directivity of antenna increases by about 43% with E-shaped metamaterial.

Miniaturized UWB multi-resonance patch antenna loaded with novel modified H-shape SRR metamaterial for microspacecraft applications

We present the design and analysis of a novel modified H-shaped split ring resonator (SRR) metamaterial. It has negative permeability and permittivity characteristics with multi-band resonance for the X, Ku, and Ka frequency bands. Different configurations of the patch antenna have been analyzed with different orientations and positions of the metamaterial. Optimized performance was achieved with the new shape of the metamaterial antenna with an appreciable 9 dB gain, 77 GHz bandwidth, 100% radiation efficiency, and 65% reduction in active area. The second-order fractal metamaterial antenna achieves high miniaturization on the order of 1/21. This is truly a boon in the communications world, as a sharp beam with smaller physical dimensions is urgently required.

High gain, directive and miniaturized metamaterial C-band antenna

Abstract In this paper, design and analysis of U–T-shaped metamaterial antenna have been presented. It shows negative permittivity and permeability characteristics. The metamaterial array is embedded inside the substrate of rectangular microstrip patch antenna. Upon incorporation, directivity increases by 24% and gain increases by 18%. Results were compared with equivalent circuit analysis of patch antenna and are well in coherence with FEM (finite-element method)-based Ansoft HFSS (high-frequency structure simulator) simulation with around 1% error. Using fractal metamaterial antenna of first and second order iterative mathematics, antenna is miniaturized by 58 and 75% along with improvement in bandwidth.

A novel metamaterial for miniaturization and multi-resonance in antenna

Abstract A new type of metamaterial-inspired patch antenna designed for having multi-resonance and minituarization has been elucidated. A novel metamaterial formed by combining 2 segment labyrinth and capacitive loaded strip has been designed by combining negative permeability and negative permittivity characteristics respectively, to form a Double Negative Group metamaterial. By adding 4 unit cells to the microstrip patch antenna resonating at 30 GHz, secondary resonances have been created around 8.5, 17.7, 20 and 23.7 GHz. Seventy-two per cent miniaturization of the structure is obtained using metamaterial-inspired antenna, but at the cost of reduction in bandwidth.