Iterative-calculation-based real-time compensation method for PGC phase demodulation error

An iterative calculation and real-time compensation technology, which is applied in the direction of converting sensor output, measuring devices, instruments, etc., can solve the problems of PGC phase demodulation error, carrier phase delay, and modulation depth nonlinear error that are difficult to compensate in real time at the same time, so as to improve accuracy , fast computing speed and high real-time effects

Active Publication Date: 2019-10-08
ZHEJIANG SCI-TECH UNIV
View PDF6 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] In order to solve the problems existing in the background technology, the present invention discloses a real-time compensation method of PGC phase demodulation error based on iterative calculation. The present invention solves the problem that the nonlinear error caused by carrier phase delay and modulation depth is difficult to be compensated in real time at the same time

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
  • Iterative-calculation-based real-time compensation method for PGC phase demodulation error
  • Iterative-calculation-based real-time compensation method for PGC phase demodulation error
  • Iterative-calculation-based real-time compensation method for PGC phase demodulation error

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0041] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0042] Such as figure 1 As shown, the specific implementation of the system of the present invention adopts a field programmable logic gate array signal processor (FPGA), and a field programmable logic gate array signal processor (FPGA) includes a frequency synthesizer 1, a first multiplier 2, a first low-pass Filter 3, correction coefficient calculation module 4 based on iterative calculation, first divider 5, second multiplier 6, second low-pass filter 7, second divider 8 and arctangent operator 9; interference signal S( t) input to the input terminals of the first multiplier 2 and the second multiplier 6, the two output terminals of the frequency synthesizer 1 are respectively connected to the input terminals of the first multiplier 2 and the second multiplier 6, the frequency synthesizer 1 is used to generate the reference signal, the output end of the first mul...

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 an iterative-calculation-based real-time compensation method for a PGC phase demodulation error. Multiplication and low-pass filtering processing are carried out on an interference signal and a local reference signal to obtain one pair of orthogonal signals; the pair of orthogonal signals is inputted into an iterative-calculation-based correction coefficient calculation module; a square vector is calculated by the orthogonal signals in the module and a prediction error and a gain matrix are further calculated; amplitudes of the orthogonal signals are predicted; multi-times iterative calculation is performed and then amplitude correction coefficients of the orthogonal signals are calculated; the amplitudes of the orthogonal signals are corrected to be 1 by using theamplitude correction coefficients and a divider; and then antitangent operation is performed on the corrected orthogonal signals to obtain a to-be-calculated phase. Therefore, a problem that the nonlinear error caused by the carrier phase delay and the modulation depth can not be compensated in real time easily in the PGC phase demodulation is solved. The iterative-calculation-based real-time compensation method having the advantage of good real-time performance can be widely applied to the technical field of sinusoidal phase modulation interferometry.

Description

technical field [0001] The invention belongs to the technical field of laser interferometry, in particular to a real-time compensation method for PGC phase demodulation errors based on iterative calculation. Background technique [0002] Phase-generated carrier (PGC) modulation and demodulation technology has the advantages of high sensitivity, large dynamic range, and strong anti-interference ability, and is widely used in laser interferometry systems such as interferometric fiber optic sensors and optical feedback interferometers. In the PGC phase demodulation technology, the interference signal is usually multiplied by the local reference signal and processed by low-pass filtering to obtain a pair of quadrature signals, and then differential cross multiplication (PGC-DCM) or arctangent (PGC-Arctan ) operation to obtain the phase to be measured. Among them, the PGC-DCM algorithm is easily affected by the interference signal amplitude fluctuation, the interference fringe c...

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): G01B9/02G01D5/26
CPCG01B9/02058G01D5/266
Inventor 严利平周春宇陈本永谢建东楼盈天
Owner ZHEJIANG SCI-TECH UNIV
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap