imec 3001 Heverlee Belgium.
School of Micro-Nano ElectronicsShanghai Jiaotong University Shanghai 200240 China.
IEEE J Transl Eng Health Med. 2024 Oct 1;12:675-683. doi: 10.1109/JTEHM.2024.3471468. eCollection 2024.
Advancements in integrated circuit (IC) technology have accelerated the miniaturization of body-worn sensors and systems, enabling long-term health monitoring. Wearable electrocardiogram (ECG), finger photoplethysmogram (PPG), and wrist-worn PPG have shown great success and significantly improved life quality. Chest-based PPG has the potential to extract multiple vital signs but requires ultra-high dynamic range (DR) IC to read out the small PPG signal among large respiration and artifacts inherent in daily life. This paper presents a dedicated high DR system for wearable chest PPG applications with a small form factor. The whole measurement system is integrated on a 20 cm2 PCB board. We have formulated a comprehensive evaluation protocol to validate the system with on-body chest PPG measurement in the workspace environment. First, chest PPG data was obtained from 6 adults and compared to data from a standard ECG patch. This system showed an average absolute deviation (AD) of 0.41 beats per minute, achieving > 99.53% heart rate (HR) accuracy. Second, chest PPG was recorded and compared to conventional PPG finger clip and PPG wristband, also showing > 98.6% HR matching and an absolute deviation in the standard deviation of NN intervals (SDNN) of < 12.8 ms for HRV monitoring within the protocol. Moreover, it successfully derives other vital parameters such as respiration rate and blood oxygen level (SpO2), showing the advancement among all these three reference modalities. This system can pave the way for new application areas, such as chest patches, to monitor chronic heart and respiratory diseases.
集成电路 (IC) 技术的进步加速了可穿戴传感器和系统的小型化，实现了长期健康监测。可穿戴心电图 (ECG)、手指光容积脉搏波 (PPG) 和手腕 PPG 已经取得了巨大的成功，显著提高了生活质量。基于胸部的 PPG 有潜力提取多个生命体征，但需要超高动态范围 (DR) IC 来读取日常生活中固有较大呼吸和伪影中的微小 PPG 信号。本文提出了一种专用于具有小外形因素的可穿戴胸部 PPG 应用的高 DR 系统。整个测量系统集成在一个 20 cm2 的 PCB 板上。我们制定了一个全面的评估方案，通过在工作环境中的体上胸部 PPG 测量来验证该系统。首先，从 6 位成年人身上获取胸部 PPG 数据，并与标准 ECG 贴片上的数据进行比较。该系统的平均绝对偏差 (AD) 为 0.41 次/分钟，心率 (HR) 准确率达到>99.53%。其次，记录胸部 PPG 并与传统的手指 PPG 夹子和手腕 PPG 带进行比较，在协议内的 HRV 监测中也显示>98.6%的 HR 匹配和标准偏差内 NN 间隔的绝对偏差 (SDNN) <12.8 ms。此外，它还成功地得出了其他生命参数，如呼吸率和血氧水平 (SpO2)，在所有这三种参考模式中都显示出了优势。该系统为新的应用领域铺平了道路，例如胸部贴片，用于监测慢性心脏和呼吸疾病。
