Design and Optimization of an Inductive-Stub-Coupled CSRR for Non-Invasive Glucose Sensing

Area of Science:

• Microwave Engineering
• Biomedical Sensors
• Metamaterials

Background:

• Diabetes mellitus necessitates accurate and continuous blood glucose monitoring.
• Current monitoring methods often involve invasive procedures or lack real-time feedback.
• Developing non-invasive sensing technologies is crucial for improved patient outcomes.

Purpose of the Study:

• To design and evaluate a high-sensitivity microwave sensor for non-invasive blood glucose monitoring.
• To enhance the performance of Complementary Split Ring Resonator (CSRR) sensors through inductive stub integration.
• To investigate the sensor's sensitivity and effectiveness across a range of glucose concentrations.

Main Methods:

• A modified CSRR architecture integrated with inductive stubs was proposed.
• Numerical simulations using a multilayer finger model were performed for performance evaluation.
• Sensor performance was analyzed for glucose concentrations from 0 to 500 mg/dL.
• Key performance metrics including frequency and amplitude sensitivity were compared with a standard CSRR.

Main Results:

• The modified CSRR sensor demonstrated dual-resonance characteristics.
• Optimized inductive loading significantly enhanced electric field localization and coupling efficiency.
• Achieved a frequency shift sensitivity of 0.086 MHz/mg/dL and amplitude sensitivity of 0.02 dB/mg/dL.
• Performance improvements of approximately 168% in frequency sensitivity and 72% in amplitude sensitivity were observed compared to the standard CSRR.

Conclusions:

• The proposed inductive stub-loaded CSRR sensor offers superior sensitivity for non-invasive glucose monitoring.
• The sensor design shows significant potential for compact, wearable, and continuous glucose monitoring systems.
• This technology represents a promising advancement for biomedical applications in diabetes management.