Accuracy Considerations for CW Radar Monitoring of Respiratory Motion

The efficacy of different CW Doppler radar demodulation methods has been assessed based on performance in tracking idealized chest motion induced by respiratory activities. The arctangent, DACM, and ScD methods were tested for accoupled and dc-coupled data. A 2.4 GHz quadrature radar system was used to measure sinusoidal modeled chest motion produced using a mechanical mover. Based on the tracking of average rate, Pearson Correlation coefficient, and peak displacement, arctangent successfully performed both rate measurement and displacement tracking. DACM and ScD were sufficient for respiratory rate measurement but not for real-time displacement tracking.