Design of Electrically Small Intraocular Antenna for Retinal Prosthesis System and Its Validation.

Area of Science:

• Biomedical Engineering
• Electromagnetics
• Antenna Design

Background:

• Retinal prostheses require miniaturized, efficient antennas for wireless communication.
• Achieving multi-band operation and specific polarization is crucial for advanced prosthetic functionality.

Purpose of the Study:

• To design and validate an ultra-miniaturized, triple-band microstrip antenna for intraocular use in retinal prostheses.
• To investigate the antenna's performance, including specific absorption rate (SAR), within eye and head models.

Main Methods:

• A circular microstrip patch was modified with annular rings and a rectangular stub, incorporating a shorting pin for multi-band operation.
• The ground plane was slotted to reduce electrical size and accommodate dense electrodes.
• Simulations and fabrication were performed, with performance validated against prior studies in eye and head models.

Main Results:

• The proposed antenna achieved triple-band operation at 1.25 GHz, 2.45 GHz, and 3.32 GHz.
• Circular polarization was obtained at 1.25 GHz with a 10 MHz axial ratio bandwidth.
• Measured results closely matched simulated parameters, confirming the antenna's viability.

Conclusions:

• The developed ultra-miniaturized antenna is suitable for intraocular applications in retinal prostheses.
• The design modifications successfully enabled triple-band operation and circular polarization.
• The antenna's performance within eye and head models indicates its potential for practical implementation.