Harmonic Multiple Loop Detection (HMLD) Algorithm for Not-Contact Vital Sign Monitoring Based on Ultra-Wideband (UWB) Radar

Abstract

In this paper, the harmonic multiple loop detection (HMLD) algorithm for heart rate (HR) and respiration rate (RR) estimation with impulse radio ultrawideband (IR-UWB) radar is introduced. The algorithm includes two parts: one is the harmonic multiple discriminant principle and the other is the cyclic spectrum updating process. The harmonic multiple discriminant principle is used to detect whether the peak point in the fundamental frequency band is the true vital sign signal. The cyclic spectrum updating process can remove the error peak point according to the results obtained from the part one. In this algorithm, threshold setting is not needed and the estimation error caused by the erroneous threshold can be reduced. Only the fundamental and second harmonic frequencies are needed for HR and RR estimation, so the algorithm has strong environmental robustness and low requirement of radar hardwares. Compared with other algorithms, HMLD algorithm provides reasonable average error rates (4.95% and 5.06%) compared to real data from the oximeter in RR and HR detection. The real-time vital signs detection experiment shows that HMLD algorithm can not only detect the vital signs rate and record the historical curve in real time, but also detect the location information, which proves the validity of HMLD algorithm in real-time vital signs detection. INDEX TERMS Harmonic multiple loop detection, biomedical signal processing, impulse radio ultrawideband (IR-UWB) radar, heart rate (HR), respiration rate (RR).

Non-Contact Vital Sign Monitoring During Sleep Through UWB Radar

“…They used Brain Products actiCHamp as a reference system for breathing estimation. Zhang et al [23] implemented harmonic multiple loop detection (HMLD) algorithm for RR and HR detection. The algorithm's RR and HR average errors were 4.95% and 5.06%, respectively.…”

Convolutional Neural Networks for the Real-Time Monitoring of Vital Signs Based on Impulse Radio Ultrawide-Band Radar during Sleep

“…A contactless radio-frequency-based monitoring solution capable of solving these problems was studied and proposed [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. This method has the advantage of being able to monitor the health of the user for a long period of time in an unconstrained manner.…”

“…Shyu et al [ 1 ] proposed the first valley peak of the energy function of the intrinsic two-layer mode-function-based ensemble empirical mode decomposition method to simultaneously extract heartbeat and breath information. Zhang et al [ 2 ] introduced a harmonic multiple-loop detection algorithm for the noncontact detection of vital signs using IR-UWB radar. Their algorithm only needed to extract fundamental and second-harmonic components to estimate vital signs.…”

Joint Vital Signs and Position Estimation of Multiple Persons Using SIMO Radar

“…To do so, several radar types have been investigated, including unmodulated continuous wave (CW) [13], frequencymodulated continuous-wave (FMCW) [14], step frequency continuous-wave (SFCW) [15], and IR-UWB [4]. Meanwhile, many signal processing techniques have been proposed, covering clutter rejection, human localization, and VS estimation [16][17][18][19][20][21]. Despite the great advances in the field, most research has focused on a single target for VS measurement.…”