Radar-based Measurement of the Body Movements of Multiple Students in Classroom Environments

TL;DR

This study demonstrates that millimeter-wave radar systems can accurately measure and monitor body movements of multiple students in classroom settings, showing high correlation with subjective evaluations and consistency across different scenarios.

Contribution

The paper introduces a radar-based method for measuring body movements of multiple students in real classroom environments, validating its accuracy and repeatability.

Findings

Correlation coefficient with subjective scores up to 0.97

High consistency between two radar systems (up to 0.78)

Feasibility of real-world multi-student movement monitoring

Abstract

We demonstrate the feasibility of the radar-based measurement of body movements in scenarios involving multiple students using a pair of 79-GHz millimeter-wave radar systems with array antennas. We quantify the body motion using the Doppler frequency calculated from radar echoes. The measurement accuracy is evaluated for two experimental scenarios, namely university students in an office and elementary school students in a classroom. The body movements measured using the two radar systems are compared to evaluate the repeatability and angle dependency of the measurement. Moreover, in the first scenario, we compare the radar-estimated body movement with subjective evaluation scores provided by two evaluators. In the first scenario, the coefficient of correlation between the radar-estimated body movement and the subjective evaluation score is 0.73 on average, with a maximum value of 0.97; in the second scenario, the average correlation coefficient of body movements measured using two radar systems is as high as 0.78. These results indicate that the proposed approach can be used to monitor the body movements of multiple students in realistic scenarios.