Complex Number Assignment in the Topology Method for Heartbeat Interval Estimation Using Millimeter-Wave Radar

TL;DR

This paper improves heartbeat interval estimation from millimeter-wave radar by theoretically determining optimal complex number assignments to feature points, replacing empirical methods, and validating the approach with real data.

Contribution

It introduces a simplified waveform model to theoretically justify complex number assignments, enhancing the accuracy of the topology method for heartbeat estimation.

Findings

Optimal complex number assignments improve estimation accuracy.

Theoretical predictions match experimental data.

Validation confirms the method's effectiveness.

Abstract

The topology method is an algorithm for accurate estimation of instantaneous heartbeat intervals using millimeter-wave radar signals. In this model, feature points are extracted from the skin displacement waveforms generated by heartbeats and a complex number is assigned to each feature point. However, these numbers have been assigned empirically and without solid justification. This study used a simplified model of displacement waveforms to predict the optimal choice of the complex number assignments to feature points corresponding to inflection points, and the validity of these numbers was confirmed using analysis of a publicly available dataset.