Patent US4041774A successfully refreshed from Google Patents.
US4041774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acoustic data acquisition device
Assignee: Boeing North American Inc
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Filing: 1976-07-02
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Granted: 1977-08-16
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Expires: 1996-07-02
Abstract
Abstract Acoustic signals are received, selectively filtered, and digitally processed, e.g., by digitizing an amplitude, the peak of an echo, or the transit time, and the digital data are stored in a memory whose storage cells are associated with particular frequencies. Other acoustical signals are similarly processed but compared with the reference data to obtain a spectral representation of differences or ratios.
Inventors
- 👤 Winfred L. Morris
- 👤 Donald O. Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:07
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/34; G01N29/348; G01S; G01S15/00; G01S15/88; G01V; G01V1/00; G01V1/28
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
82 words
Apparatus for acquiring information on acoustic properties of structural materials, comprising: means for receiving an acoustic signal from a part of such a material; means for processing the signal frequency-selectively for extracting therefrom narrow banded components having different frequencies; means for extracting digital information from said narrow banded components; means for storing digital reference information means for digitally processing the extracted digital information with the stored reference information; and means for providing a representation of the processed information in dependence upon frequency.
Claim 2
Dependent Claim
82 words
Apparatus for acquiring information on acoustic properties of structural materials, comprising: means for receiving an acoustic signal from a part of such a material; means for processing the signal frequency-selectively for extracting therefrom narrow banded components having different frequencies; means for extracting digital information from said narrow banded components; means for storing digital reference information means for digitally processing the extracted digital information with the stored reference information; and means for providing a representation of the processed information in dependence upon frequency.
Claim 3
Dependent Claim
30 words
Apparatus as in claim 1, wherein the means for extracting includes peak detection means for detecting a peak value of said component signal; and means for digitizing the peak value.
Claim 4
Dependent Claim
21 words
Apparatus as in claim 1, wherein the means for extracting includes amplitude detector means and means for digitizing the detected amplitude.
Claim 5
Dependent Claim
26 words
Apparatus as in claim 1, wherein the means for extracting includes peak detecting means and means for metering the time of occurrence of the detected peak.
Claim 6
Dependent Claim
18 words
Apparatus as in claim 4, wherein the means for metering operates in response to a launched acoustic signal.
Claim 7
Dependent Claim
60 words
Apparatus as in claim 1, including means for generating the reference information, the means for generating including the means for receiving, the means for processing and the means for extracting, to obtain particular narrow banded component signals as said references, the apparatus further including means for passing said latter component signals as said reference signals to said means for storing.
Claim 8
Dependent Claim
40 words
Apparatus as in claim 1, wherein said means for processing includes a logarithmic amplifier, the means for digitally processing including digital, arithmetic subtracting means to obtain a representation of the ratio of narrow banded component signals and said reference information.
Claim 9
Dependent Claim
26 words
Apparatus as in claim 1, wherein the means for receiving is incorporated in a means for transmitting acoustic signals, the received signals being acoustic echo signals.
Claim 10
Dependent Claim
40 words
Apparatus as in claim 1, wherein said means for processing the signal frequency-selectively includes a controlled oscillator a mixer connected to said oscillator and to said means for receiving; and a filter connected to receive the output of said mixer.
Claim 11
Dependent Claim
66 words
Apparatus for acquiring information on acoustic properties of structural material, comprising: means for receiving a relatively broad banded acoustic signal from a part of said material; means for extracting from said acoustic signal digital information on different, narrow banded portions of said signal; means for comparing said information with digital reference information, to obtain resulting information; and means for providing a spectrum of said resulting information.
Claim 12
Dependent Claim
66 words
Apparatus for acquiring information on acoustic properties of structural material, comprising: means for receiving a relatively broad banded acoustic signal from a part of said material; means for extracting from said acoustic signal digital information on different, narrow banded portions of said signal; means for comparing said information with digital reference information, to obtain resulting information; and means for providing a spectrum of said resulting information.
Claim 13
Dependent Claim
21 words
Apparatus as in claim 10, wherein the reference information includes representation of frequency dependent properties of the said means for receiving.
Claim 14
Dependent Claim
15 words
Apparatus as in claim 10, wherein the reference information includes representation of an amplitude spectrum.
Claim 15
Dependent Claim
33 words
Apparatus as in claim 10 and including means for storing said reference information, said means for comparing includes, means for arithmetically processing the digital information as extracted together with said stored reference information.
Claim 16
Dependent Claim
32 words
Apparatus as in claim 10, wherein said means for extracting is operated by control means to obtain particular digital information, the apparatus including means for storing the particular information as reference information.
Claim 17
Independent Claim
99 words
An apparatus for analyzing acoustic information resulting from interaction of acoustic signals with structural material, comprising: means for receiving a train of broad banded acoustic signals; means for analog processing the signal train as received to separate therefrom different frequency components; means for digitally processing the separated components to obtain a sequence of digital information constituting a first spectrum; means for providing digital information representing a second spectrum covering the same frequency range as the first spectrum; and means for processing the information of the first and second spectra for obtaining an indication of a normalized or referenced spectrum.
Claim 18
Independent Claim
99 words
An apparatus for analyzing acoustic information resulting from interaction of acoustic signals with structural material, comprising: means for receiving a train of broad banded acoustic signals; means for analog processing the signal train as received to separate therefrom different frequency components; means for digitally processing the separated components to obtain a sequence of digital information constituting a first spectrum; means for providing digital information representing a second spectrum covering the same frequency range as the first spectrum; and means for processing the information of the first and second spectra for obtaining an indication of a normalized or referenced spectrum.
Claim 19
Dependent Claim
19 words
Apparatus as in claim 15, wherein said spectrum represent peak amplitudes of echo signals at the different frequency components.
Claim 20
Dependent Claim
14 words
Apparatus as in claim 15, wherein said spectra represent dispersive delays of echo signals.
Claim 21
Dependent Claim
20 words
Apparatus as in claim 15 wherein means are provided to store the first spectrum, to serve subsequently as second spectrum.
Claim 22
Dependent Claim
39 words
Apparatus as in claim 15, and including control means for determining a rate of acquisition, the control means connected to and operating means for launching acoustic test signals to be received by the means for receiving following said interaction.
Claim 23
Dependent Claim
135 words
An improvement in an apparatus for acquiring information on acoustic properties of structural materials, said apparatus including means for transmitting acoustic signals into and means for receiving acoustic signals from the material, said improvement comprising: an addressable memory for storing digital information representative of particularly dispersive acoustic properties; selective filter means for filtering from a broad banded signal narrow banded components corresponding to a frequency selection; means for operating the memory and the filter means for obtaining said selection and for obtaining particular access to a portion of the memory holding reference information related to the selected frequency; means for extracting digital information from the narrow banded component as selected by the filter means; and means for digitally processing the reference information held in the accessed memory portion in relation to the extracted digital information.
Claim 24
Dependent Claim
135 words
An improvement in an apparatus for acquiring information on acoustic properties of structural materials, said apparatus including means for transmitting acoustic signals into and means for receiving acoustic signals from the material, said improvement comprising: an addressable memory for storing digital information representative of particularly dispersive acoustic properties; selective filter means for filtering from a broad banded signal narrow banded components corresponding to a frequency selection; means for operating the memory and the filter means for obtaining said selection and for obtaining particular access to a portion of the memory holding reference information related to the selected frequency; means for extracting digital information from the narrow banded component as selected by the filter means; and means for digitally processing the reference information held in the accessed memory portion in relation to the extracted digital information.
Claim 25
Dependent Claim
46 words
In an apparatus as in claim 20, said means for operating including an address counter for accessing the memory and a digital to analog converter for converting the counter state into a control signal, the selective filter means being operated in response to the control signal.
Claim 26
Dependent Claim
51 words
In an apparatus as in claim 21, said selective filter means including a voltage controlled oscillator operated by said control signal, a balanced mixer receiving an output of the voltage controlled oscillator and said broad banded signal for forming a difference-of-the-frequencies signal; and a narrow banded filter receiving said difference signal.
Claim 27
Dependent Claim
26 words
In an apparatus as in claim 20, said means for digitally processing including arithmetic means for arithmetically combining said reference information and said extracted digital information.
Claim 28
Dependent Claim
19 words
In an apparatus as in claim 23, said means for extracting including a logarithmic amplifier and amplitude responsive means.
Claim 29
Independent Claim
129 words
An apparatus for analyzing acoustic information resulting from interaction of acoustic waves with structural material, comprising: means for transmitting a series of broad band acoustic signals into the part, the signals having similar frequency spectrum; means for receiving signals resulting from interaction of the transmitted signals with the material and detecting different narrow banded portions in the different signals as received, the portions differing as to frequency of the respective narrow band; means for extracting digital information from each of the different portions; a memory containing a reference spectrum in digital representation; means connected for digitally processing the extracted digital information in relation to the stored reference spectrum, separately for each of the different frequencies; and means for generating a display or recording of the spectrum of processed signals.
Claim 30
Independent Claim
129 words
An apparatus for analyzing acoustic information resulting from interaction of acoustic waves with structural material, comprising: means for transmitting a series of broad band acoustic signals into the part, the signals having similar frequency spectrum; means for receiving signals resulting from interaction of the transmitted signals with the material and detecting different narrow banded portions in the different signals as received, the portions differing as to frequency of the respective narrow band; means for extracting digital information from each of the different portions; a memory containing a reference spectrum in digital representation; means connected for digitally processing the extracted digital information in relation to the stored reference spectrum, separately for each of the different frequencies; and means for generating a display or recording of the spectrum of processed signals.
Claim 31
Dependent Claim
27 words
An apparatus as in claim 25, including means for stepwise changing frequency selectivity in the means for receiving and detecting corresponding to the series of transmitted signals.
Claim 32
Dependent Claim
20 words
An apparatus as in claim 25, and including means for storing extracted digital information as reference spectrum in the memory.
Claim 33
Dependent Claim
25 words
Apparatus as in claim 25, wherein said reference spectrum includes frequency dependency of operation of the means for transmitting and of the means for receiving.
Claim 34
Independent Claim
177 words
An apparatus for analyzing acoustic signals resulting from interaction with a part of structural material, comprising: means for transmitting acoustic signals to the part and for receiving acoustic signals from the part; frequency selective means for providing a signal representing a narrow band of the acoustic signal as received subsequently to transmission of a acoustic signal; means for deriving digital information from said narrow band signal; a memory holding a plurality of stored digital reference information and having significance for different frequencies; circuit means for digitally processing the digital information representing the narrow band signal and said reference information as associated with the selected frequency to provide a related representation of the narrow band signal in relation to the reference information; means for varying the frequency selectivity of said selective means and for changing the access to the memory for extracting therefrom correspondingly different reference information; and means for providing a representation of different ones of said relative representations as produced by said circuit means for different selected frequency and in dependence upon the frequencies as selected.
Claim 35
Independent Claim
177 words
An apparatus for analyzing acoustic signals resulting from interaction with a part of structural material, comprising: means for transmitting acoustic signals to the part and for receiving acoustic signals from the part; frequency selective means for providing a signal representing a narrow band of the acoustic signal as received subsequently to transmission of a acoustic signal; means for deriving digital information from said narrow band signal; a memory holding a plurality of stored digital reference information and having significance for different frequencies; circuit means for digitally processing the digital information representing the narrow band signal and said reference information as associated with the selected frequency to provide a related representation of the narrow band signal in relation to the reference information; means for varying the frequency selectivity of said selective means and for changing the access to the memory for extracting therefrom correspondingly different reference information; and means for providing a representation of different ones of said relative representations as produced by said circuit means for different selected frequency and in dependence upon the frequencies as selected.
References Cited (Backward Citations)
US3857052A
Cited
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-08-15 | 1981-02-14 | 1981-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-15 | 1985-02-14 | 1985-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-15 | 1989-02-14 | 1989-08-16 | $7700.00 | Window Closed / Lapsed |