Bias-Free Optically Controlled Pattern-Reconfigurable Planar Antenna

Area of Science:

• Electrical Engineering
• Electromagnetics
• Wireless Communication

Background:

• Reconfigurable antennas are crucial for adaptive wireless systems.
• Traditional bias-line networks for antenna reconfiguration can be complex and introduce interference.
• Need for efficient, bias-free solutions for pattern diversity in sub-6 GHz applications.

Purpose of the Study:

• To present a novel antenna-level bias-line-free, optically controlled pattern-reconfigurable planar antenna.
• To demonstrate a compact and wideband solution for sub-6 GHz wireless systems.
• To enable flexible radiation pattern switching without complex biasing networks.

Main Methods:

• Design of a planar antenna with four tapered-slot radiating units.
• Integration of a reconfigurable feeding network using four light-dependent resistors (LDRs) and LEDs.
• Optical control of LDRs for selective activation of feed arms, enabling pattern reconfiguration.

Main Results:

• The antenna supports ten distinct radiation states, including principal, diagonal, and dual-beam patterns.
• Achieved impedance matching across the 3.3-6.7 GHz band for all states (<-10 dB |S11|).
• Measured realized gain of 5.8-6.3 dBi and total radiation efficiency of 86-90%.

Conclusions:

• The proposed optically controlled antenna offers a compact, wideband, and bias-free platform for pattern reconfiguration.
• This technology is suitable for coverage and interference adaptation in sub-6 GHz wireless systems.
• Demonstrates a practical implementation for advanced wireless communication needs.