Circularly Polarized Reconfigurable MIMO Antenna for WLAN Applications

Area of Science:

• Electromagnetics and Applied Physics
• Wireless Communication Systems
• Metamaterial Applications

Background:

• Multiple-input multiple-output (MIMO) systems enhance wireless communication capacity.
• Circularly polarized (CP) antennas mitigate polarization mismatch and fading.
• Reconfigurable antennas offer adaptable performance for dynamic wireless environments.

Purpose of the Study:

• To present a simple, reconfigurable two-element antenna design for MIMO WLAN applications.
• To achieve flexible control over circular polarization (CP) states (RHCP/LHCP) for individual ports.
• To demonstrate high performance metrics including matching, axial ratio, and inter-port isolation.

Main Methods:

• Design of a two-element antenna incorporating a reconfigurable feeding network, CP source, and a 2x2 unit-cell metasurface (MS).
• Utilization of PIN diodes to control the ON/OFF states for polarization reconfigurability.
• Performance evaluation through simulation and/or measurement at 2.45 GHz.

Main Results:

• The proposed antenna achieves a matching performance below -10 dB across operating modes.
• An axial ratio lower than 3 dB is maintained for all polarization configurations.
• Superior inter-port isolation exceeding 24 dB is achieved, alongside satisfactory MIMO diversity performance.
• The design offers advantages in gain, size, and a simplified switching mechanism using few PIN diodes.

Conclusions:

• The developed antenna provides a simple and effective solution for reconfigurable CP in MIMO WLAN systems.
• The design demonstrates excellent performance characteristics and practical advantages over existing solutions.
• This work contributes to the advancement of adaptable and efficient wireless communication antenna technologies.