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Large angle beam steering THz antenna using active frequency selective surface based on hybrid graphene-gold
Optics Express
|August 18, 2018
Summary
This study presents a 360-degree beam steering terahertz (THz) antenna using a hybrid graphene-gold active frequency selective surface (AFSS). The novel design allows for flexible beam direction and gain control in THz wireless systems.
Area of Science:
- Terahertz (THz) technology
- Antenna engineering
- Metamaterials
Background:
- Designing reconfigurable THz antennas for optimal performance is challenging.
- Achieving large-angle beam steering in the terahertz band remains a significant hurdle.
Purpose of the Study:
- To propose a novel 360-degree beam steering THz antenna.
- To enable flexible beam direction and gain control for reconfigurable THz wireless systems.
Main Methods:
- Utilizing an active frequency selective surface (AFSS) based on a hybrid graphene-gold structure.
- Coating a THz omnidirectional monopole antenna with a hexagonal AFSS screen.
- Tuning the chemical potential of graphene to control AFSS states (ON/OFF) for beam steering.
Main Results:
- Demonstrated 360-degree beam steering capability by controlling AFSS states.
- Achieved continuously variable reflection and transmission coefficients via tunable graphene chemical potential.
- Enabled adjustable radiation gain (enlarged or suppressed) for the THz antenna.
Conclusions:
- The proposed THz antenna offers a unique solution for large-angle beam steering.
- The continuously tunable AFSS provides flexible control over antenna radiation characteristics.
- This technology is promising for advanced reconfigurable THz wireless communication systems.
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