The accuracy of the heart rate (HR) estimated from the photoplethysmography (PPG) signal is always skeptical due to the ubiquity of the motion artifact (MA) in the signal. To ensure the HR estimated from the PPG signal is accurate, a new algorithm is proposed for the removal of MA component from the PPG signal using accelerometer signals. In this paper, the combination of adaptive filters using single noise reference signal referred to as CASINOR is proposed. The recursive least square (RLS) and normalized least mean square (NLMS) adaptive filters are used for denoising the PPG signals. The selection of single noise reference signal is based on the power value of the accelerometer signals. The MA-reduced PPG signals obtained from these RLS and NLMS filters are combined to a single PPG signal using sigmoid function, and the HR is estimated. The estimated HR is refined by using phase vocoder. The proposed method resulted in less HR estimation error of 1.92 beat per minute (BPM) on 23 PPG datasets (IEEE SP CUP 2015). Reduced error value, less computational time and improved accuracy augment this technique to be implemented in wearable devices.

中文翻译：

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CASINOR：自适应滤波器的组合使用单个噪声参考信号从 PPG 信号估计心率

由于信号中运动伪影 (MA) 的普遍性，根据光电容积脉搏波 (PPG) 信号估计的心率 (HR) 的准确性始终令人怀疑。为了确保从 PPG 信号中估计出的 HR 是准确的，提出了一种使用加速度计信号从 PPG 信号中去除 MA 分量的新算法。在本文中，提出了使用称为 CASINOR 的单噪声参考信号的自适应滤波器组合。递归最小二乘 (RLS) 和归一化最小均方 (NLMS) 自适应滤波器用于对 PPG 信号进行去噪。单个噪声参考信号的选择基于加速度计信号的功率值。使用 sigmoid 函数将从这些 RLS 和 NLMS 滤波器获得的 MA 减少的 PPG 信号组合成单个 PPG 信号，并估计 HR。估计的 HR 是通过使用相位声码器来细化的。所提出的方法在 23 个 PPG 数据集 (IEEE SP CUP 2015) 上导致每分钟 1.92 次心跳 (BPM) 的 HR 估计误差较小。减少的错误值、更少的计算时间和提高的准确性增强了该技术在可穿戴设备中的应用。