Method for filtering baseline drift by using lifting wavelet transformation

A baseline drift and wavelet transform technology, applied in the field of signal processing, can solve problems such as baseline drift errors, and achieve the effect of filtering out baseline drift

Inactive Publication Date: 2014-12-24
GUILIN UNIV OF ELECTRONIC TECH
View PDF5 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a method for filtering baseline drift by using lifting wavelet transform, which solves the problem that the baseline drift obtained by the existing method has a large error

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for filtering baseline drift by using lifting wavelet transformation
  • Method for filtering baseline drift by using lifting wavelet transformation
  • Method for filtering baseline drift by using lifting wavelet transformation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0019] The present invention will be described in detail below in combination with specific embodiments.

[0020] Aiming at the poor effect of traditional filtering volumetric pulse wave baseline drift, a method of filtering baseline drift by using lifting wavelet transform is proposed, which is carried out according to the following steps:

[0021] Step 1: Use the HKG-70 infrared pulse wave sensor to collect the volumetric pulse wave signal at the fingertips. The sampling frequency used is 200Hz. After filtering by the filter circuit and the 16-order low-pass FIR filter with a cutoff frequency of 10Hz written inside the MSP430 microcontroller A total of 2400 discrete pulse wave data were collected, and the pulse wave data was transmitted to a PC through a USB transmission line and stored as a TXT file.

[0022] Step 2: Use the bior2.2 wavelet function to decompose the pulse wave data stored in the TXT file into 6 layers by using the lifting wavelet transform. The specific pro...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for filtering a baseline drift by using lifting wavelet transformation. The method comprises the following steps: filtering a volume pulse wave signal through a low-pass FIR (far-infrared) filter; carrying out six-layer decomposition on pulse wave data which is stored in a TXT document by using a bior2.2 wavelet basis function and a db4 wavelet basis function by virtue of lifting wavelet transformation; respectively clearing low-frequency approximation coefficients in the sixth scale, which are obtained by decomposition twice, and reconstructing approximation coefficients in the sixth scale and high-frequency detail coefficients in the first scale to the sixth scale; utilizing pulse wave signal data which is reconstructed by the bior2.2 wavelet basis function in the front 0.6 part, and utilizing the pulse wave data which is reconstructed by the db4 wavelet basis function in the rear 0.4 part; reconstructing the signal which is equal to the original volume pulse wave signal in length by combining the pulse wave signal data with the pulse wave data. The method has the beneficial effects that: the method has an obvious effect on filtration of the baseline drift in the volume pulse wave signal, and the main details of the signal are well reserved when the baseline drift is filtered.

Description

technical field [0001] The invention belongs to the technical field of signal processing, and relates to a method for filtering baseline drift by using lifting wavelet transform. Background technique [0002] The baseline drift in the pulse wave belongs to low-frequency interference, generally below 1Hz. Scholars have proposed many solutions to suppress the baseline drift in the pulse wave. The commonly used methods include offset method and filtering method. The offset method uses the original pulse wave The signal subtracts the estimated signal of the baseline drift to achieve the purpose of eliminating the baseline drift, and the baseline drift obtained by this method has a large error. Filtering methods include average filtering, median filtering, curve fitting, high-pass filtering, morphological processing, and wavelet decomposition. High-pass filtering will cause waveform distortion of the pulse wave, and the morphological method will slightly shift. The method of curv...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): A61B5/02
Inventor 陈真诚朱健铭梁永波刘彦伟
Owner GUILIN UNIV OF ELECTRONIC TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products