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Frequency conversion and parametric amplification using a virtually rotating metasurface.

Zohreh Seyedrezaei, Behzad Rejaei, Mohammad Memarian

|April 1, 2020

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This study introduces virtually rotating metasurfaces (VRM) for electromagnetic wave frequency conversion. These surfaces enable efficient up or down conversion and amplification of microwave signals without magnetic fields.

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Area of Science:

Electromagnetics and Metamaterials
Applied Physics
Microwave Engineering

Background:

Metasurfaces offer unique electromagnetic wave manipulation capabilities.
Time-varying metasurfaces are emerging for dynamic control of wave properties.
Achieving frequency conversion with metasurfaces typically requires complex designs.

Purpose of the Study:

To analyze electromagnetic wave scattering from time-varying metasurfaces mimicking rotation.
To propose and analyze a metasurface-based frequency converter with amplification.
To develop and validate models for virtually rotating metasurfaces (VRM).

Main Methods:

Theoretical analysis of circularly polarized wave scattering from a time-dependent metasurface.
Utilizing a rotating frame transformation for time-invariant analysis and phasor representation.
Validation through 1D-Finite-Difference Time-Domain (FDTD) simulations and a lumped element model.

Main Results:

Scattered fields exhibit frequency conversion by twice the metasurface rotation frequency.
A proposed system achieves full conversion to a single up/down-converted tone, with amplification for up-conversion.
Lumped element and 3D models successfully demonstrate the VRM concept, validated by simulations.

Conclusions:

Virtually rotating metasurfaces enable efficient, linear, and magnetless frequency conversion and amplification.
The proposed system offers a simple yet effective design for frequency conversion applications.
This work opens new avenues for dynamic control of electromagnetic waves.