A microwave imaging-based technique to localize an in-body RF source for biomedical applications

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Electromagnetics

Background:

• Accurate localization of in-body radio-frequency (RF) sources is crucial for biomedical applications like wireless capsule endoscopy.
• Precise positioning of abnormalities enables targeted therapeutic operations within the gastrointestinal tract.
• Tissue electrical properties (permittivity and conductivity) are key to estimating internal positions.

Purpose of the Study:

• To present a novel method for localizing an in-body RF source using microwave imaging.
• To estimate the position of an RF source by analyzing tissue electrical properties derived from microwave imaging.
• To evaluate the accuracy of the proposed localization method under noisy conditions.

Main Methods:

• Microwave imaging was employed to determine the electrical properties of tissues at 403.5 MHz.
• A 2-D simulation model was developed, including a circular phantom and a realistic phantom.
• White Gaussian noise was added to simulated data to mimic real-world conditions.
• The position of the RF source was estimated based on the generated microwave images.

Main Results:

• The proposed algorithm demonstrated accurate localization of the RF source in both simulated phantom models.
• The root-mean-square error was within 10 mm for the circular phantom and 4 mm for the realistic phantom.
• The method proved effective even with the addition of significant white Gaussian noise.

Conclusions:

• The developed microwave imaging technique offers a capable and accurate solution for in-body RF source localization.
• The algorithm's robustness to noise makes it suitable for practical biomedical applications.
• This method enhances the potential for precise therapeutic interventions guided by internal source positioning.