利用胸部运动调制无线电信号的非接触式PPG信号获取
Non-Contact Acquisition of PPG Signal using Chest Movement-Modulated Radio Signals
AI总结：
本文首次提出利用胸部运动调制的无线电信号实现非接触式PPG信号获取，通过SDR采集、PCA降维、小波去噪和DCT域非线性回归重建PPG波形，在16名受试者数据集上取得平均绝对误差8.1294，可用于传染病患者的心血管与呼吸系统非接触评估。
摘要：
我们首次提出一种新方法，利用胸部运动调制的无线电信号实现光电容积脉搏波（PPG）信号的非接触式获取。在所提方法中，一台软件定义无线电（SDR）以5.24 GHz中心频率、64个子载波的正交频分复用信号照射附近受试者的胸部，同时另一台紧邻的SDR采集经胸部反射的调制无线电信号。通过这种方式，我们构建了一个自定义数据集，采集了来自16名健康年轻受试者的160分钟带标签数据（包括原始无线电数据以及参考PPG信号）。在此基础上，我们首先利用主成分分析对无线电数据进行降维。接着，使用小波技术对无线电信号和参考PPG信号进行去噪，随后进行分割和Z-score归一化。然后，我们利用互相关方法同步无线电段和PPG段。最后，我们进入波形转换（回归）任务，首先使用离散余弦变换（DCT）将无线电段和PPG段转换到频域，再学习它们之间的非线性回归关系。最终，通过对回归模块输出进行逆DCT重建合成PPG信号，平均绝对误差为8.1294。合成PPG波形具有重要的临床意义，因为它可用于对患有传染病（例如covid19）的患者进行心血管和呼吸系统的非接触式性能评估。
英文摘要：
We present for the first time a novel method that utilizes the chest movement-modulated radio signals for non-contact acquisition of the photoplethysmography (PPG) signal. Under the proposed method, a software-defined radio (SDR) exposes the chest of a subject sitting nearby to an orthogonal frequency division multiplexing signal with 64 sub-carriers at a center frequency 5.24 GHz, while another SDR in the close vicinity collects the modulated radio signal reflected off the chest. This way, we construct a custom dataset by collecting 160 minutes of labeled data (both raw radio data as well as the reference PPG signal) from 16 healthy young subjects. With this, we first utilize principal component analysis for dimensionality reduction of the radio data. Next, we denoise the radio signal and reference PPG signal using wavelet technique, followed by segmentation and Z-score normalization. We then synchronize the radio and PPG segments using cross-correlation method. Finally, we proceed to the waveform translation (regression) task, whereby we first convert the radio and PPG segments into frequency domain using discrete cosine transform (DCT), and then learn the non-linear regression between them. Eventually, we reconstruct the synthetic PPG signal by taking inverse DCT of the output of regression block, with a mean absolute error of 8.1294. The synthetic PPG waveform has a great clinical significance as it could be used for non-contact performance assessment of cardiovascular and respiratory systems of patients suffering from infectious diseases, e.g., covid19.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
