Dual-band dual-circularly polarized and orbital angular momentum multiplexed reflectarray

Area of Science:

• Electromagnetics and Applied Physics
• Antenna Theory and Design
• Metamaterials and Metasurfaces

Background:

• Satellite communication systems require efficient dual-band antennas capable of handling complex signal multiplexing.
• Orbital Angular Momentum (OAM) multiplexing offers a promising approach to increase data capacity by encoding information in the phase front of electromagnetic waves.
• Reflectarray (RA) antennas provide a low-profile, high-gain solution for various applications, including satellite communications.

Purpose of the Study:

• To propose and demonstrate a novel dual-band, dual-circularly polarized (CP) reflectarray (RA) antenna utilizing orbital angular momentum (OAM) multiplexing.
• To achieve effective decoupling between dual-band operations and integrate multiple multiplexing techniques (frequency, polarization, OAM).
• To design a low-profile metasurface unit cell capable of broadband operation and efficient OAM beam generation.

Main Methods:

• Design of a low-profile metasurface unit cell using a dielectric substrate and a metal patch for broadband operation (10.6-18.1 GHz).
• Integration of frequency, polarization, and OAM multiplexing techniques within the RA design.
• Development of an RA structure capable of generating distinct OAM beams with specific polarizations and radiation directions for different frequency bands.

Main Results:

• A wide operational bandwidth of 52.2% (10.6 GHz to 18.1 GHz) was achieved with the designed metasurface unit cell.
• The proposed RA successfully generated a left-handed CP OAM beam (l=+1) in the downlink band (10.7-12.75 GHz).
• A right-handed CP beam (l=-2) was generated in the uplink band (12.75-18.1 GHz), with each beam exhibiting a unique radiation direction.

Conclusions:

• The developed dual-band, dual-CP OAM-multiplexed RA fulfills the duplex communication requirements for Ku-band satellite systems.
• The innovative design demonstrates effective dual-band dual-CP decoupling and integration of multiple multiplexing schemes.
• This work presents a significant advancement in antenna technology for high-capacity satellite communication by enabling distinct OAM beams with tailored polarizations and radiation patterns.