Vasu V, Fox N, Heneghan C, Sezer S
The Institute of Electronics, Communications and Information Technology, Queen's University Belfast, BT3 9DT, Northern Ireland, U.K.
Annu Int Conf IEEE Eng Med Biol Soc. 2010;2010:2407-10. doi: 10.1109/IEMBS.2010.5626125.
We describe a contact-less method for measurement of respiration rate during sleep using a 5.8GHz radio-frequency bio-motion sensor. The sensor operates by sensing phase shifts in reflected radio waves from the torso caused by respiratory movements and other bodily movements such as twitches, positional changes etc. These non-respiratory motion artefacts can obscure reliable estimation of breathinig rates if conventional spectral analysis is used. This paper reports on the accuracy of the respiration rate estimates obtained via algorithmic approaches using Lomb-periodogram based analysis (which can deal with missing or corrupted data), as compared to conventional spectral analysis. Gold-standard respiration rates are derived by expert scoring of respiration rates measured through polysomnography (PSG) from sensors (Respiratory Inductance Plethysmography (RIP) belts) in contact with the subject in an accredited sleep laboratory. Specifically, respiration rates for 15-minute segments chosen from 10 subjects free of Sleep-Disorded Breathing (AHI〈5) were selected for analysis in this paper. Comparison to the expert annotation indicates strong agreement, with the Lomb-periodogram respiration rates with the average error between the measurements being less than 0.4 breaths/min and a standard deviation of 0.3 breaths/minute. Moreover, we showed that the proposed algorithm could track respiration rate over the complete night's recordings for those 10 subjects. We conclude that the non-contact biomotion sensor may provide a promising approach to continuous respiration rate monitoring of reasonable accuracy.
我们描述了一种使用5.8GHz射频生物运动传感器在睡眠期间测量呼吸频率的非接触式方法。该传感器通过检测由呼吸运动以及其他身体运动（如抽搐、体位变化等）引起的来自躯干的反射无线电波中的相位变化来工作。如果使用传统的频谱分析，这些非呼吸运动伪影可能会干扰呼吸频率的可靠估计。本文报告了与传统频谱分析相比，通过基于Lomb周期图分析的算法方法（可处理缺失或损坏的数据）获得的呼吸频率估计的准确性。金标准呼吸频率是通过在认可的睡眠实验室中，由专家对通过多导睡眠图（PSG）从与受试者接触的传感器（呼吸感应体积描记法（RIP）带）测量的呼吸频率进行评分得出的。具体而言，本文选择了从10名无睡眠呼吸障碍（呼吸暂停低通气指数〈5）的受试者中选取的15分钟时间段的呼吸频率进行分析。与专家注释的比较表明高度一致，Lomb周期图呼吸频率测量之间的平均误差小于0.4次/分钟，标准差为0.3次/分钟。此外，我们表明所提出的算法可以跟踪这10名受试者整个夜间记录的呼吸频率。我们得出结论，这种非接触式生物运动传感器可能为连续呼吸频率监测提供一种具有合理准确性的有前景的方法。
