Skip to main content


  • Research Article
  • Open Access
  • A New Method for Identifying the Life Parameters via Radar

    EURASIP Journal on Advances in Signal Processing20072007:031415

    • Received: 10 January 2006
    • Accepted: 6 October 2006
    • Published:


    It has been proved that the vital signs can be detected via radar. To better identify the life parameters such as respiration and heartbeat, a novel method combined with several signal processing techniques is presented. Firstly, to improve the signal-to-noise ratio (SNR) of the life signals, the signal accumulation technique by FFT is used. Then, to restrain the interferences produced by moving objects, a dual filtering algorithm (DFA) which is able to remove the interferences by tracing the interfering spectral peaks is proposed. Finally, the wavelet transform is applied to separate the heartbeat from the respiration signal. The method cannot only help to automatically detect the existence of human beings effectively, but also identifying the parameters like respiration, heartbeat, and body-moving signals significantly. Experimental results demonstrated that the method is very promising in identifying the life parameters via radar.


    • Radar
    • Respiration
    • Information Technology
    • Signal Processing
    • Vital Sign

    Authors’ Affiliations

    The Key Laboratory of Education, Ministry of China, Xi'an Jiaotong University, Xi'an, 710049, China
    Department of Biomedical Engineering, The Fourth Military Medical University, Xi'an, 710032, China


    1. Jianqi W, Wang HB, Xijing J, et al.: The study on non-contact detection of breathing and heartbeat based on radar principles. Chinese Journal of Medical Instrumentation 2001,25(3):132-135.Google Scholar
    2. Jianqi W, Chongxun Z, Xijing J, Guohua L, Wang H-B, Ni A-S: Study on a non-contact life parameter detection system using millimeter wave. Space Medicine and Medical Engineering 2004,17(3):157.Google Scholar
    3. Droitcour A, Boric-Lubecke O, Lubecke V, Lin J: 0.25mm CMOS and BiCMOS single chip direct conversion Doppler radars for remote sensing of vital signs. Proceedings of IEEE International Solid State Circuits Conference (ISSCC '02), February 2002, San Francisco, Calif, USA 348–349.Google Scholar
    4. Droitcour A, Boric-Lubecke O, Lubecke V, Lin J, Kovacs G: Range correlation effect on ISM band I/Q CMOS radar for non-contact vital signs sensing. Proceedings of IEEE MTT-S International Microwave Symposium Digest (IMS '03), June 2003, Philadelphia, Pa, USA 3: 1945–1948.Google Scholar
    5. Chen K-M, Huang Y, Zhang J, Norman A: Microwave life-detection systems for searching human subjects under earthquake rubble or behind barrier. IEEE Transactions on Biomedical Engineering 2000,47(1):105-114. 10.1109/10.817625View ArticleGoogle Scholar
    6. Matthews G, Sudduth B, Burrow M: A non-contact vital signs monitor. Critical Reviews in Biomedical Engineering 2000,28(1-2):173-178.View ArticleGoogle Scholar
    7. Chuang H-R, Chen YF, Chen KM: Automatic clutter-canceller for microwave life-detection systems. IEEE Transactions on Instrumentation and Measurement 1991,40(4):747-750. 10.1109/19.85346View ArticleGoogle Scholar
    8. Chen KM, Misra D, Wang H, Chuang H-R, Postow E: An X-band microwave life-detection system. IEEE Transactions on Biomedical Engineering 1986,33(7):697-701.View ArticleGoogle Scholar
    9. Xuehong L, Aipin W, Liye W: Restraining the respiration interferences in ECG signal based on wavelet transform. Journal of Biomedical Engineering and Clinical of China 2003,6(7):78-82.Google Scholar
    10. Donoho DL: De-noising by soft-thresholding. IEEE Transactions on Information Theory 1995,41(3):613-627. 10.1109/18.382009MathSciNetView ArticleGoogle Scholar
    11. Adair ER, Gandhi OP: Subcommittee co-chairs, IEEE Standard for Safety Levels with Respect to Human Exposure to Radio frequency Electromagnetic Field, 3kHz to 300 GHz(IEEE c95.1-1991). 1994.Google Scholar


    © Wang Jianqi et al. 2007

    This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.