Radiation source screening and positioning method based on STFT time frequency analysis

A technology of time-frequency analysis and positioning method, applied in the direction of measuring devices, instruments, measuring electricity, etc., to achieve the effect of reducing loop area, suppressing radiation noise, and reducing common mode current

Inactive Publication Date: 2015-04-08
NANJING NORMAL UNIVERSITY
View PDF10 Cites 16 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to overcome the defects of the existing technology, no longer according to the traditional rectification method based on experience, but by finding the corresponding device that causes the radiation to exceed the standard, quickly and effectively suppress the excessive noise of the equipment

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
  • Radiation source screening and positioning method based on STFT time frequency analysis
  • Radiation source screening and positioning method based on STFT time frequency analysis
  • Radiation source screening and positioning method based on STFT time frequency analysis

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0033] The present invention will be further described in detail with the example of PCB, which is composed of two crystal oscillators of 20MHz and 6MHz. Put the PCB board, oscilloscope, two magnetic field probes and wires according to figure 1 Place it on the test bench after connecting.

[0034] Step 1: First, conduct a time-domain test on the PCB board, use two magnetic field probes to measure two sets of time-domain signals, and obtain two sets of observed signals x 1 (t),x 2 (t).

[0035] Step 2: For the measured mixed time-domain signal, first form the two sets of mixed signals into a 2*10000 matrix x, and perform independent component analysis on the observed signal x, that is, to find a separation matrix W so that y=Wx has a maximum Gaussian, the signal is separated into two independent signals z 1 (t),z 2 (t), as attached figure 2shown.

[0036] The third step: the separated signal z 1 (t) Carry out STFT time-frequency analysis, the results are as attached ...

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 radiation source screening and positioning method based on STFT time frequency analysis. According to the method, an independent component analysis ICA algorithm is in combination with STFT, and a systematic, comprehensive, standardized radiated EMI analysis and diagnosis method is proposed. Firstly, radiation noise of EUT is separated through an ICA algorithm, and multiple radiation noise sources are screened out; secondly, short-time rapid Fourier transform and time frequency analysis on exceeding-standard frequency ranges of the overall radiation noise are carried out, and signal characteristics causing exceeding-standard radiation are extracted; lastly, the extracted signal characteristics and the multiple radiation noise sources screened out by the ICA are contrasted, positioning diagnosis on the noise sources causing exceeding-standard radiation noise is carried out, and pertinent rectification inhibition measures are adopted. The method can rapidly and effectively inhibit exceeding-standard noise of equipment through searching the corresponding device causing exceeding-standard radiation.

Description

technical field [0001] The invention relates to a radiation source screening and positioning method based on STFT time-frequency analysis, and belongs to the technical field of electromagnetic compatibility. Background technique [0002] In recent years, with the continuous emergence of a large number of power electronic equipment or systems, radiated EMI noise superimposed on the space field will affect the normal operation of itself and surrounding electronic equipment. According to GB 9254, the test frequency range for radiated EMI noise is 30MHz to 1GHz. Therefore, the identification and diagnosis of the electromagnetic radiation noise source of electronic equipment has become the biggest challenge in EMI fault analysis. [0003] Research on radiated noise usually includes three aspects: identification, prediction and suppression of radiation sources. Radiation source identification refers to the acquisition and determination of information such as the characteristics, ...

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): G01R29/08G01R31/00
Inventor 赵阳张杨夏欢李世锦宋百通魏薇杨博婷
Owner NANJING NORMAL UNIVERSITY
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