Abstract
In this paper, an ultrathin planar nonlinear metamaterial slab is designed and simulated. Nonlinearity is provided through placing diodes in each metamaterial unit cell. The diodes are auto-biased and activated by an incident wave. The proposed structure represents a broadband switching property between two transmission and reflection states depending on the intensity of the incident wave. High permittivity values are presented creating a near zero effective impedance at low power states, around the second resonant mode of the structure unit cell; as the result, the incident wave is reflected. Increasing the incident power to the level which can activate the loaded diodes in the structure results in elimination of the resonance and consequently a drop in the permittivity values near the permeability one as well as a switch to the transmission state. A full wave as well as a nonlinear simulations are performed. An optimization method based on weed colonization is applied to the unit cell of the metamaterial slab to achieve the maximum switching bandwidth. The structure represents a 24% switching bandwidth of a 10 dB reduction in the reflection coefficient.
Highlights
Many scientists have focused on this topic during the past decades by introducing metamaterial structures which have special electromagnetic characteristics not found in nature, for instance, negative μr [1] and εr [2]
A nonlinear switching bandwidth of 22.6%, centered at 3.05 GHz, with at least a 10 dB reduction in the reflection coefficient is achieved by the proposed structure
The full wave and nonlinear simulations verified the nonlinear broadband switching between the reflection and transmission behavior of the designed planar metamaterial structure
Summary
Many scientists have focused on this topic during the past decades by introducing metamaterial structures which have special electromagnetic characteristics not found in nature, for instance, negative μr [1] and εr [2]. Active controlling circuits are not applicable to cases which need fast response to the intensity of the incident wave in microwave frequency ranges. These applications include high power limiting [11], switching applications [12], and harmonic generations [13]. We designed and simulated a broadband planar switching metamaterial and provided the switching property through auto-biased diodes in metamaterial unit cells. The full wave simulations are provided, where the optimization algorithm is applied to the structure and the optimum values for the maximum bandwidth are obtained.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
