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A number of algorithms have been developed to extract heart rate from physiological motion data using Doppler radar system. Yet, it is very challenging to eliminate noise associated with surroundings, especially with a single-channel Doppler radar system. However, single-channel Doppler radars provide the advantage of operating at lower power. Additionally, heart rate extraction using single-channel Doppler radar has remained somewhat unexplored. This has motivated the development of effective signal processing algorithms for signals received from single-channel Doppler radars. Three algorithms have been studied for estimating heart rate. The first algorithm is based on applying FFT on an FIR filtered signal. In the second algorithm, autocorrelation was performed on the filtered data. Thirdly, a peak finding algorithm was used in conjunction with a moving average preceded by a clipper to determine the heart rate. The results obtained were compared with heart rate readings from a pulse oximeter. With a mean difference of 2.6 bpm, the heart rate from Doppler radar matched that from the pulse oximeter most frequently when the peak finding algorithm was used. The results obtained using autocorrelation and peak finding algorithm (with standard deviations of 2.6 bpm and 4.0 bpm) suggest that a single channel Doppler radar system can be a viable alternative to contact heart rate monitors in patients for whom contact measurements are not feasible.
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A Multi-Arc Method for Improving Doppler RadarMotion Measurement Accuracy
In this paper a phase shifter based multi-arc circle fitting method was proposed to improve accuracy of Doppler radar remote motion sensing. Experiments were conducted to validate the approach by measuring displacement of 3 mm using 2.4 GHz quadrature continuous wave (CW) Doppler radar. It was demonstrated that mean error drops from 4.529% to 1.073% when multiple shifting arcs are utilized to enhance detection accuracy. A greater improvement in accuracy is observed when more arcs are applied.
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- Award ID(s):
- 1660253
- PAR ID:
- 10129119
- Date Published:
- Journal Name:
- 2018 IEEE/MTT-S International Microwave Symposium - IMS
- Page Range / eLocation ID:
- 244 to 247
- Format(s):
- Medium: X
- 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/MWSYM.2018.8439687
