Conical conformal OAM-generating transmitarray with high transmission double C-shaped grating metasurface.

Area of Science:

• Electromagnetics and Metamaterials
• Antenna Engineering
• Wave Physics

Background:

• Orbital angular momentum (OAM) vortex waves offer unique properties for advanced wireless systems.
• Conformal antennas are crucial for integration into various platforms, but designing them for OAM generation remains challenging.

Purpose of the Study:

• To propose and validate a conical conformal transmitarray (CCTA) capable of generating orbital angular momentum (OAM) vortex waves.
• To develop a high-transmission metasurface element for broadband phase control.
• To establish a design methodology for conformal OAM generation on curved surfaces.

Main Methods:

• Design of a double C-shaped grating metasurface element for 360° phase coverage (11-13 GHz) with high transmission (>0.92).
• Implementation of a ring layout method for the CCTA with derived phase compensation and element number formulas.
• Simulation, fabrication, and measurement of three CCTA prototypes to validate the conformal design.

Main Results:

• The proposed metasurface element achieved excellent phase coverage and high transmission.
• The ring layout and derived formulas enabled consistent coupling and effective phase control.
• Measured results closely matched simulations, confirming the CCTA's ability to generate OAM vortex beams on conformal platforms.

Conclusions:

• The developed CCTA with a double C-shaped grating metasurface is an effective solution for generating OAM vortex waves on conformal platforms.
• The proposed design methodology provides a viable approach for future conformal OAM applications in communications and detection.
• This work advances the integration of OAM technology into practical, non-planar systems.