Technische Hochschule Lübeck, University of Applied Sciences, 23562 Lübeck, Germany.
Institute of Biomedical Engineering, University of Lübeck, 23562 Lübeck, Germany.
Sensors (Basel). 2020 Dec 29;21(1):165. doi: 10.3390/s21010165.
The measurement and analysis of the arterial pulse wave provides information about the state of vascular health. When measuring blood pressure according to Riva-Rocci, the systolic and diastolic blood pressure is measured non-invasively with an inflatable pressure cuff on the upper arm. Today's blood pressure monitors analyze the pulse wave in reference to the rising or falling cuff pressure. With the help of additional pulse wave analysis, one can determine the pulse rate and the heart rate variability. In this paper, we investigated the concept, the construction, and the limitations of ultrawideband (UWB) radar and continuous wave (CW) radar, which provide continuous and non-invasive pulse wave measurements. We integrated the sensors into a complete measurement system. We measured the pulse wave of the cuff pressure, the radar sensor (both UWB and CW), the optical sensor, and ultrasonic Doppler as a reference. We discussed the results and the sensor characteristics. The main conclusion was that the resolution of the pulse radar was too low, even with a maximum bandwidth of 10 GHz, to measure pulse waves reliably. The continuous wave radar provides promising results for a phantom if adjusted properly with phase shifts and frequency. In the future, we intend to develop a CW radar solution with frequency adaption.
动脉脉搏波的测量和分析提供了有关血管健康状况的信息。在根据里瓦-罗西（Riva-Rocci）测量血压时，通过在上臂上充气的压力袖带无创地测量收缩压和舒张压。如今的血压监测器分析脉搏波以参考上升或下降的袖带压力。借助额外的脉搏波分析，可以确定脉搏率和心率变异性。在本文中，我们研究了超宽带（UWB）雷达和连续波（CW）雷达的概念、结构和局限性，这两种雷达都提供连续的非侵入性脉搏波测量。我们将传感器集成到完整的测量系统中。我们测量了袖带压力、雷达传感器（UWB 和 CW）、光学传感器和超声多普勒的脉搏波作为参考。我们讨论了结果和传感器特性。主要结论是，即使使用 10GHz 的最大带宽，脉冲雷达的分辨率也太低，无法可靠地测量脉搏波。连续波雷达如果相位偏移和频率调整得当，对于模拟物将提供有希望的结果。在未来，我们打算开发具有频率自适应功能的 CW 雷达解决方案。
