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The quality of human respiratory motion measurements made with Doppler radar depends on the amount of reflected signal received and the overall signal to noise ratio (SNR) of the measurement. The non-uniform characteristics of the human torso and its motion impact both the amount of signal returned toward the radar and its polarization. This study used a 2.4 GHz continuous wave Doppler radar system to compare the respiratory motion measurement performance for circular polarized antennas and linear polarized antennas, using mechanical respiratory phantom measurements at a nominal distance of one meter. While the different surfaces examined produced varied levels of signal at the original and other polarizations, the measurements using circular polarized antennas consistently provided less overall received signal and no significant improvement of SNR.
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Analysis of Polarimetric Radar Effects in Respiratory Measurements
Physiological Doppler radar measurements for respiration do not typically take into consideration polarimetric effects caused by scattering from the irregular surface of the respiring torso. This study investigated the performance of a physiological Doppler radar system using both vertically and horizontally polarized transmit antennas, each in combination with both vertically and horizontally polarized receive antennas. Return signatures were analyzed for robotic phantom targets with varied arrangements of curvature, and for a representative group of human subjects. The results showed that while cylindrical targets generated significant amounts of cross-polarized return signal, typical human subject return signals produced an even larger proportion of cross-polarized signal.
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- PAR ID:
- 10547790
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-5105-7
- Page Range / eLocation ID:
- 15 to 17
- Subject(s) / Keyword(s):
- Physiological radar polarimetric radar human respiration
- Format(s):
- Medium: X
- Location:
- Montreal, QC, Canada
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/IMBioC60287.2024.10590580
