Wearable Dual Polarized Electromagnetic Knee Imaging System.

Area of Science:

• Biomedical Engineering
• Electromagnetics
• Medical Imaging

Background:

• Sport injuries, particularly knee injuries, are increasing, necessitating early and onsite detection.
• Current detection methods may not be suitable for early-stage injury assessment.
• Electromagnetic imaging (EMI) shows promise but requires advanced systems for accurate fluid detection.

Purpose of the Study:

• To develop a portable, dual-polarized wearable electromagnetic imaging (EMI) system for early knee injury detection.
• To design and integrate a compact antenna array into a textile brace for knee monitoring.
• To evaluate the system's performance in reconstructing images of knee injuries.

Main Methods:

• An 8-element dual-polarized aperture antenna array was designed using textile wool-felt as a flexible substrate.
• Each antenna was compact (36 ×36 ×3.1 mm³) with orthogonal coaxial feeds and a ground plane.
• The double stage delay, multiply and sum algorithm (DS-DMAS) was employed for image reconstruction.

Main Results:

• The antenna array operated effectively over a 0.7-3.3 GHz band (130% bandwidth) with a front-to-back ratio > 10 dB.
• The wearable system successfully reconstructed images of knee injuries on realistic models and phantoms.
• The dual-polarized system demonstrated superior performance compared to single-polarized configurations.

Conclusions:

• The proposed dual-polarized wearable EMI system is efficient for onsite knee injury detection.
• The compact antenna design and flexible substrate enable practical application in a textile brace.
• This technology offers a promising advancement for early diagnosis and management of knee injuries.