Waveform analyzer

• US 5,784,285 A
• Filed: 01/31/1997
• Issued: 07/21/1998
• Est. Priority Date: 01/31/1996
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Tohya, Hirokazu, Masuda, Norio, Tamaki, Naoya
• Primary Examiner(s): Voeltz, Emanuel Todd
• Assistant Examiner(s): PEESO, THOMAS R
• Application Number:
  US08/792,732
• Time in Patent Office: 536 Days
• Field of Search: 364/487, 364/572, 324/76.12, 324/76.19, 324/76.29, 367/38, 367/43, 367/56, 367/60
• US Class Current: 702/66
• CPC Class Codes: G01R 23/16 Spectrum analysis; Fourier analysis
• CPC Class Codes: G01R 29/0814 Field measurements related to measuring influence on or from apparatus, components or humans EMC, EMI and similar testing in general G01R31/001, e.g. in ESD, EMI, EMC, EMP testing, measuring radiation leakage; detecting presence of micro- or radiowave emitters; dosimetry; testing shielding; measurements related to lightning
• CPC Class Codes: G01R 29/0892 Details related to signal analysis or treatment; presenting results, e.g. displays; measuring specific signal features other than field strength, e.g. polarisation, field modes, phase, envelope, maximum value

Abstract

Disclosed is a waveform analyzer, which inputs measured data of an electronic device to be analyzed; generates an orthogonal analyzing wavelet; produces wavelet-analyzed components in which the measured data is wavelet-transformed into a plurality of wavelet spectra by using the orthogonal analyzing wavelet, thereafter the plurality of wavelet spectra are inverse-wavelet-transformed to produce the wavelet-analyzed components; and adds up a component with an order corresponding to a desired filter characteristic of the wavelet-analyzed components to get a filtered waveform.

Claims

1. A waveform analyzer, comprising:

means for inputting measured data of an electronic device to be analyzed;

means for generating an orthogonal analyzing wavelet;

means for producing wavelet-analyzed components in which said measured data is wavelet-transformed into a plurality of wavelet spectra by using said orthogonal analyzing wavelet, thereafter said plurality of wavelet spectra are inverse-wavelet-transformed to produce said wavelet-analyzed components; and

means for adding up a component with an order corresponding to a desired filter characteristic of said wavelet-analyzed components to get a filtered waveform.

2. A waveform analyzer, according to claim 1, wherein:

said adding up means adds up a first order component to a desirable order component of said wavelet-analyzed components, if said desired filter characteristic is of a low-pass filter, said adding up means adds up a middle order component to the maximum order component of said wavelet-analyzed components, if said desired filter characteristic is of a high-pass filter, and said adding up means adds up an optional middle order component except said first order component and said maximum order component of said wavelet-analyzed components, if said desired filter characteristic is of a band-pass filter.

3. A waveform analyzer, comprising:

means for inputting measured data of an electronic device to be analyzed;

means for generating an orthogonal analyzing wavelet;

means for producing wavelet-analyzed components in which said measured data is wavelet-transformed into a plurality of wavelet spectra by using said orthogonal analyzing wavelet, thereafter said plurality of wavelet spectra are inverse-wavelet-transformed to produce said wavelet-analyzed components;

means for analyzing a correlation between each of said wavelet analyzed components and said measured data input by said inputting means; and

means for adding up a component with a correlation analysis result bigger than a threshold value of said wavelet-analyzed components to get a waveform in which a component with a correlation analysis result smaller than said threshold value is removed.

4. A waveform analyzer, comprising:

means for inputting measured data of an electronic device to be analyzed;

means for generating an orthogonal analyzing wavelet and a window function;

means for producing wavelet-analyzed components by wavelet-analyzing a limited time section of said measured data by using said orthogonal analyzing wavelet and said window function; and

means for adding up a component with an order corresponding to a desired filter characteristic of said wavelet-analyzed components to get a filtered waveform.

5. A waveform analyzer, according to claim 4, wherein:

said adding up means adds up a first order component to a desirable order component of said wavelet-analyzed components, if said desired filter characteristic is of a low-pass filter, said adding up means adds up a middle order component to the maximum order component of said wavelet-analyzed components, if said desired filter characteristic is of a high-pass filter, and said adding up means adds up an optional middle order component except said first order component and said maximum order component of said wavelet-analyzed components, if said desired filter characteristic is of a band-pass filter.

6. A waveform analyzer, comprising:

means for inputting measured data of an electronic device to be analyzed;

means for generating an orthogonal analyzing wavelet and a window function;

means for producing wavelet-analyzed components by wavelet-analyzing a limited time section of said measured data by using said orthogonal analyzing wavelet and said window function;

means for analyzing a correlation between each of said wavelet analyzed components and said measured data input by said inputting means; and

means for adding up a component with a correlation analysis result bigger than a threshold value of said wavelet-analyzed components to get a waveform in which a component with a correlation analysis result smaller than said threshold value is removed.