Doppler signal period distribution demodulation method of laser Doppler velocimeter

A Doppler velocimeter and Doppler signal technology, which is applied in the direction of instruments, measuring devices, electromagnetic wave reradiation, etc., can solve the problems of affecting frequency demodulation results, speed measurement curve burrs, poor anti-interference ability, etc., to achieve The effect of suppressing the widening or narrowing of the signal cycle, eliminating calculation errors, and improving the accuracy of signal processing

Inactive Publication Date: 2011-11-09
XIAN MODERN CHEM RES INST
View PDF3 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Since the period count demodulation method of the Doppler signal is used to obtain a certain time period t g The average frequency of the entire cycle N in the cycle, the signal cycle change caused by the instability of the sc

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
  • Doppler signal period distribution demodulation method of laser Doppler velocimeter
  • Doppler signal period distribution demodulation method of laser Doppler velocimeter
  • Doppler signal period distribution demodulation method of laser Doppler velocimeter

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0034] The present invention will be further described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0035] The preferred embodiment of the invention is implemented by a computer data processing system. When a heterodyne interferometer is used to measure the velocity of the target by laser Doppler, the velocity Doppler signal output by the heterodyne interferometer is collected and stored in real time by a digital oscilloscope. After the measurement, the computer data processing system reads the speed measurement Doppler signal saved by the digital oscilloscope and transfers it to the computer hard disk. Then, you can follow the Figure 5The workflow shown performs frequency demodulation of the Doppler signal.

[0036] In the first step, relevant parameters used in demodulation processing are set. These parameters include the cycle count period length t of the Doppler signal demodulation process g , and at a t g The maximum num...

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 Doppler signal period distribution demodulation method of a laser Doppler velocimeter. The time domain processing principle based on a period counting method is adopted, the average frequency in all periods in each set time period is not calculated, but the time value distribution of each period in each time period is analyzed, and the most frequent time value in the time value distribution is taken as the period length in the time period and is converted into the signal frequency in the time period. The Doppler signal period distribution demodulation method has the main advantages of improving the calculation precision of Doppler frequency shift signal processing and effectively reducing the influence of widening or narrowing of the Doppler frequency shift signal period, losing of part of signals and noise, which are caused by the instability of the scattered light, on the test result of the target movement velocity.

Description

technical field [0001] The invention belongs to the technical field of laser Doppler velocimetry, and mainly relates to a time-domain demodulation method of a Doppler signal of a laser Doppler velocimeter, in particular to a heterodyne interferometer for measuring the velocity of a fixed moving target Doppler signal periodic distribution demodulation method. Background technique [0002] The Doppler effect will occur when the light source and the object move relative to each other. The laser Doppler velocimeter relies on the frequency shift between the scattered light of the moving particles and the irradiated light to obtain the velocity information. The commonly used optical heterodyne interferometer principle of the reference light mode See attached figure 1 . single frequency f 0 When the laser beam is irradiated on a moving object, the frequency of the received scattered light is f 0 +Δf D , where Δf D is the frequency shift between the scattered light and the ill...

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
IPC IPC(8): G01S7/48G01S17/58
Inventor 寿光裕苏健军姬建荣王国庆
Owner XIAN MODERN CHEM RES INST
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