Design of High Temperature Complex Dielectric Properties Measuring System Based on XGBoost Algorithm.

Area of Science:

• Materials Science
• Electrical Engineering
• Microwave Engineering

Background:

• Accurate measurement of material dielectric properties at high temperatures is crucial for understanding microwave-matter interactions.
• Existing methods for high-temperature permittivity measurement often face challenges in real-time data acquisition and accuracy.

Purpose of the Study:

• To propose and validate an online system for measuring relative complex permittivity at high temperatures.
• To develop a robust inversion model for calculating dielectric coefficients using microwave interferometry data.
• To enhance measurement accuracy through system calibration.

Main Methods:

• Utilized a ridge waveguide with TE10 mode for simultaneous heating and measurement at 2450 MHz.
• Employed a microwave interferometer to capture amplitude and phase differences of incident signals.
• Developed an inversion model using the Extreme Gradient Boosting (XGBoost) algorithm trained on simulation data.
• Applied linear regression (LR) for system calibration to improve accuracy.

Main Results:

• The system demonstrated high-temperature measurement capabilities, tested up to 800 °C with Macor materials.
• Room temperature tests with various materials showed a maximum measurement error of less than 8% compared to theoretical data.
• The Extreme Gradient Boosting (XGBoost) algorithm effectively calculated complex dielectric coefficients.

Conclusions:

• The proposed online system provides an effective method for high-temperature complex permittivity measurements.
• The XGBoost-based inversion model and LR calibration enhance measurement accuracy and robustness.
• This technique facilitates a deeper understanding of microwave-matter interactions at elevated temperatures.