Design of a multi-passband metasurface with ultra-high angular stability based on complementary frequency selective...

Area of Science:

• Electromagnetics and Metamaterials
• Applied Physics
• Electrical Engineering

Background:

• Metasurfaces offer unique electromagnetic properties but often struggle with angular stability and multiband functionality.
• Frequency Selective Surfaces (FSSs) are crucial for filtering electromagnetic waves, with demand for compact and stable multiband designs increasing.

Purpose of the Study:

• To propose and validate a new design for a multi-passband metasurface with exceptional angular stability.
• To demonstrate a simplified design process for achieving dual- to penta-passband FSSs with ultra-low thickness.

Main Methods:

• Design of a multi-passband metasurface utilizing complementary frequency selective surfaces (FSSs) with coupled ring slots.
• Analysis using an equivalent circuit model (ECM) to understand the relationship between structure and passband count.
• Fabrication and experimental measurement of a penta-band FSS prototype.

Main Results:

• Achieved ultra-low thickness of 0.004λ and demonstrated dual- to penta-passband capabilities.
• The penta-band FSS exhibited insertion loss < 1.0 dB and validated the design concept through experimental results.
• The metasurface showed polarization insensitivity and maintained stable filter response up to 80° incidence angles.

Conclusions:

• The proposed complementary FSS design offers a simplified approach to creating ultra-thin, stable multi-passband metasurfaces.
• The design demonstrates significant potential for advanced filtering applications requiring wide angular stability and multiband operation.