Multiband metamaterial microwave absorbers using split ring and multiwidth slot structure

Abstract

This article proposes a multiband metamaterial microwave absorber based on a split ring‐slot structure. Both simulation and experimental measurements are carried out to obtain the scattering parameters which are used to retrieve the absorption coefficient, relative permittivity, and relative permeability. The influences on the absorption produced by geometrical dimensions, incidence angles and polarisation angles are investigated from 1.5 to 18.0 GHz. The results show that the absorber possesses three resonance peaks with absorption greater than 70% measured experimentally at 3.0, 5.8, and 11.0 GHz. The absorption performance is insensitive to the angle of incidence, θ up to 60°.The absorption mechanisms are studied based on the surface current distribution, electric field distribution, and constitutive parameters (μ r and ε r). Furthermore, a mechanical mean using dielectric material to tune the absorption frequencies (up to 1.0 GHz of tuning range) and enhance the absorption bandwidth (up to 50%) is demonstrated.

Compact polarisation insensitive wide angular stable triple band absorber for RF energy harvesting, RCS reduction, and sensor applications

“…The air spacer in the pressure sensor is replaced with different materials, as shown in Figure 9A. The variation in reflectivity is observed when we change the sensor layer with different materials like FR-4, Arlon AD 300A (1.9 g/cm 3 ), Arlon AD 350A, and Arlon AD 410A having mass density 1.9 g/cm 3 , 2.07 g/cm 3 , 2.40 g/cm 3 and 2.10 g/cm 3 , respectively. Overall, the reflection coefficient differs from the material we placed.…”

“…Electromagnetic (EM) absorbers can absorb the EM radiation by inhibiting the reflection as well as transmission. It has been widely used in many applications like Radar Cross Section (RCS) reduction in stealth technology, 1 mutual coupling reduction between the antennas, 2 Electromagnetic Interference (EMI) suppression, 3 sensors, 4 and RF energy harvesting. 5 Salisbury screen was the first conventional microwave absorber consisting of a simple uniform resistive sheet with free space impedance on the top of a λ g /4 grounded dielectric substrate.…”

Multi-band Metasurface Microwave Absorber Based on Square Split-Ring Resonator Structure

“…To achieve a perfect absorptivity of metamaterial absorber, its impedance needs to match the impedance of free space, by tailoring the effective permittivity and permeability of metamaterial. These metamaterial absorbers were developed in a single frequency band [9,10], dual-band [11], and multi-band [12][13][14].…”

RCS reduction of microstrip antenna using split square loop thin absorber

“…Triple‐band metamaterial absorbers have been designed using an outer circular metal ring with an inner Jerusalem cross [1] and circular fractal structure [2]. Metamaterial inspired double split serration ring structure [3] and split‐ring‐slot structure [4] have been used to achieve the multiband absorption. The RCS of a waveguide slot antenna is reduced by covering its perfect electric conductor ground plane by metamaterial absorber in [5].…”