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Decomposition of respiratory and cardiac phase fluctuations using dual-band distributed CW radar

Published online by Cambridge University Press:  07 November 2025

Min Kim ,
Eugin Hyun ,
Youngseok Jin ,
Jieun Bae ,
Sangbin Cha ,
Jieun Lee  and
Inoh Choi Open the ORCID record for Inoh Choi [Opens in a new window]
Min Kim
Affiliation:
Department of Maritime ICT and Mobility Research, Korea Institute of Ocean Science and Technology, Busan, South Korea
Eugin Hyun
Affiliation:
Department of Future Automotive Technology Research, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
Youngseok Jin
Affiliation:
Department of Future Automotive Technology Research, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
Jieun Bae
Affiliation:
Department of Future Automotive Technology Research, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
Sangbin Cha
Affiliation:
Department of Electronic Engineering, Pukyong National University, Busan, South Korea
Jieun Lee
Affiliation:
Department of Smart Mobility Engineering, Pukyong National University, Busan, South Korea
Inoh Choi*
Affiliation:
Department of Smart Mobility Engineering, Pukyong National University, Busan, South Korea
*
Corresponding author: Inoh Choi; Email: inoh@pknu.ac.kr
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Abstract

Respiratory and cardiac rates can be estimated by analyzing a spectrum of linearly mixed phase fluctuations in a radar echo of an individual. However, there are high-order harmonics caused by time-varying respiratory rate, and the interference effect of the respiratory rate and its harmonics makes it difficult to estimate the cardiac rate with relatively low energy in a spectrum. To solve this problem, we exploit the independent component analysis method with dual-band distributed continuous wave radar for effective decomposition of phase fluctuations corresponding to respiratory and cardiac rates. In simulations and experiments, the respiratory and cardiac rates were successfully estimated by the proposed decomposition method, compared with conventional methods.

Keywords

cardiac ratedual-band distributed continuous wave radarhigh-order harmonicsindependent component analysisrespiratory rate

Information

Type
Research Paper
Information
International Journal of Microwave and Wireless Technologies , First View , pp. 1 - 10
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Copyright
© The Author(s), 2025. Published by Cambridge University Press in association with The European Microwave Association.

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References

Choi, I, Park, S, Kim, M, Cha, S, Jin, Y, Bae, J and Hyun, H (2024) Decomposition of respiratory and cardiac rates using dual band distributed radar. In Proceedings of the 21st European Radar Conference (EuRAD), 324–327.CrossRefGoogle Scholar
Schires, E, Georgiou, P and Lande, TS (2018) Vital sign monitoring through the back using an UWB impulse radar with body coupled antennas. IEEE Transactions on Biomedical Circuits and Systems 12, 292–302. https://doi.org/10.1109/TBCAS.2018.2799322CrossRefGoogle ScholarPubMed
Zhang, Y, Qi, F, Lv, H, Liang, F and Wang, J (2019) Bioradar technology: Recent research and advancements. IEEE Microwave Magazine 20, 58–73. https://doi.org/10.1109/MMM.2019.2915491CrossRefGoogle Scholar
Chen, KM, Huang, Y, Zhang, J and Norman, A (2000) Microwave life-detection systems for searching human subjects under earthquake rubble or behind barrier. IEEE Transactions on Biomedical Engineering 47, 105–114. https://doi.org/10.1109/10.817625CrossRefGoogle ScholarPubMed
Forouzanfar, M,Mabrouk, M, Rajan, S, Bolic, M, HR, Dajani and VZ, Groza (2016) Event recognition for contactless activity monitoring using phase-modulated continuous wave radar. IEEE Transactions on Biomedical Engineering 64, 479–491. https://doi.org/10.1109/TBME.2016.2566619CrossRefGoogle ScholarPubMed
Adib, F, Mao, H, Kabelac, Z, Katabi, D and Miller, RC (2015) Smart homes that monitor breathing and heart rate. In Proceedings of the 33rd Annual ACM Conference on Human Factors in Computing Systems, 837–846.CrossRefGoogle Scholar
Choi, I, Kim, M, Choi, J, Park, J, Park, S and Kim, K (2021) Robust cardiac rate estimation of an individual. IEEE Sensors Journal 21, 15053–15064. https://doi.org/10.1109/JSEN.2021.3074510CrossRefGoogle Scholar
He, M, Nian, Y and Liu, B (2015) Noncontact heart beat signal extraction based on wavelet transform. In Proceedings of the 8th International Conference on Biomedical Engineering and Informatics. (BMEI), 14–16.CrossRefGoogle Scholar
Feng, J and Pan, S (2010) Extraction algorithm of vital signals based on empirical mode decomposition. Journal of South China University of Technology 38, 1–6.Google Scholar
Wang, Y, Yang, Z, Han, L, Li, Y and Zhang, C (2023) Extraction of vital sign based on improved complete ensemble empirical mode decomposition with adaptive noise for UWB radar. 2023 IEEE 6th International Electrical and Energy Conference (CIEEC), 2829–2834.CrossRefGoogle Scholar
Ding, C, Yan, J, Zhang, L, Zhao, H, Hong, H and Zhu, X (2017) Noncontact multiple targets vital sign detection based on VMD algorithm. In Proceedings of the IEEE Radar Conference (RadarConference), 8–12.CrossRefGoogle Scholar
Xia, ZL, Wang, XH, Wei, HB and Xu, Y (2021) Detection of vital signs based on variational mode decomposition using FMCW radar. 2021 International Conference on Microwave and Millimetre Wave Technology (ICMMT), 1–3.CrossRefGoogle Scholar
Qu, L, Liu, C, Yang, T and Sun, Y (2023) Vital sign detection of FMCW radar based on improved adaptive parameter variational mode decomposition. IEEE Sensors Journal 23, 25048–25060. https://doi.org/10.1109/JSEN.2023.3312513CrossRefGoogle Scholar
Liu, Z, Kong, Y, Zhang, X, Wu, J and Wei, L (2020) Vital sign extraction in the presence of radar mutual interference. IEEE Signal Processing Letters 27, 1745–1749. https://doi.org/10.1109/LSP.2020.3026942.CrossRefGoogle Scholar
Chen, Y, Yuan, J and Tang, J (2024) A high precision vital signs detection method based on millimetre wave radar. Scientific Reports 14, 25535.Google ScholarPubMed
Choi, I, Kang, K, Kim, K and Park, S (2022) Use of ICA to separate micro-doppler signatures in ISAR images of aircraft that has fast-rotating parts. IEEE Transactions on Aerospace and Electronic Systems 58, 234–246. https://doi.org/10.1109/TAES.2021.3098110CrossRefGoogle Scholar
Hyvarinen, A, Karhunen, J and Oja, E. (2001) Independent Component Analysis. Hoboken, NJ, USA: WileyCrossRefGoogle ScholarPubMed
Bingham, E and Hyvarinen, A (2000) A fast fixed-point algorithm for independent component analysis of complex valued signals. International Journal of Neural Systems 10, 1–8. https://doi.org/10.1142/S0129065700000028CrossRefGoogle ScholarPubMed
Kammersgaard, NPB, Kvist, SH, Thaysen, J and Jakobsen, KB (2019) Geometrical theory of diffraction formulation for on-body propagation. IEEE Transactions on Antennas and Propagation 67, 1143–1152. https://doi.org/10.1109/TAP.2018.2882596CrossRefGoogle Scholar
Jin, Y, Bae, J, Choi, I, Kim, M, Park, C and Hyun, E (2023) Detection method of human gait-rate and vital-sign using dual-baseband Doppler radar In Apsar 2023. Bali Island, Indonesia, pp. 1–4.Google Scholar
Park, J, Lee, G, Lee, I and Yang, J (2025) Heart rate extraction technique with mitigation of respiration harmonic for bio-radar sensors. IEEE Sensors Journal 25, 929–939. https://doi.org/10.1109/JSEN.2024.3491753CrossRefGoogle Scholar