EP0161423B1 - Method for determining the boundaries of a signal mixed with background noise - Google Patents
Method for determining the boundaries of a signal mixed with background noise Download PDFInfo
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- EP0161423B1 EP0161423B1 EP85103259A EP85103259A EP0161423B1 EP 0161423 B1 EP0161423 B1 EP 0161423B1 EP 85103259 A EP85103259 A EP 85103259A EP 85103259 A EP85103259 A EP 85103259A EP 0161423 B1 EP0161423 B1 EP 0161423B1
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10L—SPEECH ANALYSIS OR SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING; SPEECH OR AUDIO CODING OR DECODING
- G10L25/00—Speech or voice analysis techniques not restricted to a single one of groups G10L15/00 - G10L21/00
- G10L25/78—Detection of presence or absence of voice signals
- G10L25/87—Detection of discrete points within a voice signal
Definitions
- the present invention relates to a method for detecting the limits of signals which occur in front of a background signal mixture, in particular signal limits for the speech processing of words spoken in front of a background noise, the amplitude behavior of which is used as a distinguishing criterion between a signal of interest and the background signal or background signal mixture.
- the present invention has for its object to provide a method of the type mentioned, which can be carried out inexpensively, in terms of both hardware and software, but works relatively accurately and from certain irrelevant signal disturbances (for example the sound of a banging door , Street noise, the voices of a large number of people and the like) remain unaffected.
- the method according to the present invention uses their amplitude behavior as a distinguishing criterion between a signal of interest and the background signal or background signal mixture.
- a recorded and then preprocessed signal or signal mixture namely an input variable E
- E is observed within a predetermined time interval with regard to its mean amplitude A and its first frequency of passage N, which is based on a reference variable R, and its fluctuation range dN, the frequency of passage N being off
- Individual passage frequencies is determined and the fluctuation range is determined by the maximum deviation of the individual passage frequencies.
- the recorded signal or signal mixture Z (t) is first amplified, then filtered by means of a bandpass filter and then subjected to an analog / digital conversion, as a result of which the input variable E is obtained, see FIG. 1 Auxiliary variables S1, N2 derived, compare FIG. 3.
- the current frequency of passage N1 is determined in relation to the reference variable R.
- one of the previously derived auxiliary variables S1 or S2 is assigned to an evaluation variable S.
- the current input variable E is measured on the basis of this evaluation variable S.
- an operation 01 which is dependent on the position of the input variable E relative to the evaluation variable S is carried out.
- Two limit values UG, OG1 are defined on the basis of the type of signal of interest. The result of operation 01 is limited by the first limit.
- the second, upper limit value OG1 is reached, the presence of a signal of interest is recognized.
- the exact start of the signal SB is a defined time period ahead of the relevant orken time of ZE1, compare Figure 4 and Figure 5.
- a third step the position of the input variable E relative to the evaluation variable S is evaluated by a further operation 02 in such a way that when a second limit value OG2 predetermined based on the type of the signal of interest is reached, the absence of the signal of interest acquired in the second step is present is detected.
- the exact end of the signal SE is a defined time period before the relevant detection time ZE2, see FIG. 7.
- said operation 01 is provided as an integration process.
- the exact start of the signal SB is determined by the temporal position of the last value of the integration result equal to the lower limit value UG before the relevant detection time ZE1.
- the first step can advantageously be repeated in the event that the input variable E exceeds a threshold adapted to the background signal mixture.
- a waiting period is expediently inserted between the first step and the second step.
- auxiliary variables are defined as follows: where the quantities a, b, c and d are constants which are determined by empirical values or by the type of the signal of interest.
- the evaluation variable S is defined as follows: The first operation is defined as follows: The second operation is defined as follows:
- processing and evaluation processes according to the invention can be carried out by means of digital circuits, but are expediently to be carried out by means of a microprocessor and corresponding programs therefor.
- FIG. 2 shows a flow diagram for a word boundary detection.
- the steps mentioned, namely the first step, the second step and the third step, are illustrated again clearly in this flowchart.
- FIG. 8 shows, as already explained at the beginning, a diagram for an entire word boundary recognition of the spoken word “stop”, in the upper part of the diagram a waveform of the relevant time signal with assigned upper and lower threshold values, and the middle part of the diagram a generated digital display signal for the State "word of interest is present" and the process of word start and word end recognition is shown in the lower part of the diagram.
- the environmental noise will have dominant frequency components in the area of the vowel formants.
- these formants mostly have relatively large amplitudes, so that they can also be detected at a high threshold.
- the method according to the invention is of course not limited to the exemplary embodiments described.
- it can also be used for monitoring purposes to find certain typical signal profiles within a signal mixture, for example for radio monitoring purposes.
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- Acoustics & Sound (AREA)
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- Compression, Expansion, Code Conversion, And Decoders (AREA)
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Abstract
Description
Die vorliegende Erfindung betrifft ein Verfahren zur Erfassung der Grenzen von Signalen, die vor einem Hintergrundsignalgemisch auftreten, insbesondere von Signalgrenzen für die Sprachverarbeitung von vor einem Hintergrundgeräusch gesprochenen Wörtern, wobei als Unterscheidungskriterium zwischen einem interessierenden Signal und dem Hintergrundsignal oder Hintergrundsignalgemisch deren Amplitudenverhalten herangezogen wird.The present invention relates to a method for detecting the limits of signals which occur in front of a background signal mixture, in particular signal limits for the speech processing of words spoken in front of a background noise, the amplitude behavior of which is used as a distinguishing criterion between a signal of interest and the background signal or background signal mixture.
Bisherige Lösungen zur Wortgrenzendetektion reichen von einfachen Signalamplituden-Betrachtungen bis zur Analyse des Zeitsignals mit nachfolgender Erkennung und Klassifikation in Pause und Sprache.Previous solutions for word boundary detection range from simple signal amplitude considerations to analysis of the time signal with subsequent recognition and classification in pause and speech.
Die Beurteilung der mittleren Amplitude von Hintergrundsignalen bzw. des Amplitudenverhaltens allgemein reicht jedoch in zahlreichen Anwendungsfällen nicht aus. Eine vollständige Analyse hinsichtlich beispielsweise des Frequenzverhaltens - ausgedrückt durch Parameter - und/ oder des Amplitudenverhaltens, wie aus dem Stand der Technik bekannt, ist jedoch für zahlreiche Anwendungsfälle zu aufwendig, und zwar betreffend sowohl. die Hardware als auch die Software.However, the assessment of the mean amplitude of background signals and of the amplitude behavior in general is not sufficient in numerous applications. However, a complete analysis with regard to, for example, the frequency behavior - expressed by parameters - and / or the amplitude behavior, as is known from the prior art, is too complex for numerous applications, both with regard to. the hardware as well as the software.
Der vorliegenden Erfindung liegt die Aufgabe zugrunde, ein Verfahren der eingangs genannten Art zu schaffen, das kostengünstig, und zwar bezüglich der Hardware als auch der Software, durchzuführen ist, jedoch verhältnismässig genau arbeitet und von bestimmten irrelevanten Signalstörungen (zum Beispiel das Geräusch einer schlagenden Tür, Strassenlärm, die Stimmen einer Vielzahl von Menschen u. dgl.) unbeeinflusst bleibt.The present invention has for its object to provide a method of the type mentioned, which can be carried out inexpensively, in terms of both hardware and software, but works relatively accurately and from certain irrelevant signal disturbances (for example the sound of a banging door , Street noise, the voices of a large number of people and the like) remain unaffected.
Die der vorliegenden Erfindung zugrundeliegende Aufgabe wird durch ein Verfahren der eingangs genannten Art bzw. gemäss dem Oberbegriff des Patentanspruchs 1 gelöst, das durch die im kennzeichnenden Teil des Patentanspruchs 1 angegebenen Merkmale charakterisiert ist.The object on which the present invention is based is achieved by a method of the type mentioned at the outset or according to the preamble of
Vorteilhafte Weiterbildungen der Erfindung sind durch die in den Unteransprüchen angegebenen Merkmale gekennzeichnet.Advantageous developments of the invention are characterized by the features specified in the subclaims.
Die vorliegende Erfindung wird im folgenden anhand mehrerer Ausführungsbeispiele für die Erfindung betreffender Figuren im einzelnen erläutert.
Figur 1 zeigt ein schematisches Blockschaltbild, aus dem das Grundprinzip der Vorverarbeitung des Zeitsignals eines an eine Eingangsklemme einer entsprechenden Einrichtung zur Durchführung des Verfahrens gelegten Eingangssignals hervorgeht.- Figur 2 zeigt ein Ablaufdiagramm von Schritten zur Wortgrenzendetektion gemäss der vorliegenden Erfindung.
- Figur 3 zeigt ein schematisches Blockschaltbild, aus dem Einrichtungen und deren Zusammenwirken zur Durchführung eines ersten Verfahrensschrittes hervorgehen.
- Figur 4 zeigt ein Blockschaltbild, aus dem Einrichtungen und deren Zusammenwirkung zur Durchführung einer «Beginn-Detektion» hervorgehen.
- Figur 5 zeigt eine Diagrammdarstellung eines Beispiels für die «Beginn-Detektion» des gesprochenen Wortes «Stop».
- Figur 6 zeigt ein Blockschaltbild, aus dem Einrichtungen und deren Zusammenwirken für eine «Ende-Detektion» hervorgehen.
- Figur 7 zeigt eine Diagrammdarstellung eines Beispiels für die «Ende-Detektion» des gesprochenen Wortes «Stop».
- Figur 8 zeigt eine Diagrammdarstellung eines Beispiels für eine gesamte Wortgrenzenerkennung für das gesprochene Wort «Stop».
- FIG. 1 shows a schematic block diagram, from which the basic principle of preprocessing the time signal of an input signal connected to an input terminal of a corresponding device for carrying out the method emerges.
- FIG. 2 shows a flow diagram of steps for word boundary detection according to the present invention.
- FIG. 3 shows a schematic block diagram from which devices and their interaction for carrying out a first method step emerge.
- FIG. 4 shows a block diagram from which devices and their interaction for carrying out a “start detection” result.
- FIG. 5 shows a diagram of an example of the “start detection” of the spoken word “stop”.
- FIG. 6 shows a block diagram from which devices and their interaction for an “end detection” result.
- FIG. 7 shows a diagram of an example of the “end detection” of the spoken word “stop”.
- FIG. 8 shows a diagram of an example of an overall word boundary recognition for the spoken word “stop”.
Wie bereits eingangs ausgeführt, benutzt das Verfahren gemäss der vorliegenden Erfindung als Unterscheidungskriterium zwischen einem interessierenden Signal und dem Hintergrundsignal oder Hintergrundsignalgemisch deren Amplitudenverhalten. Dazu wird in einem ersten Schritt ein aufgenommenes und anschliessend vorverarbeitetes Signal oder Signalgemisch, nämlich eine Eingangsgrösse E, hinsichtlich seiner mittleren Amplitude A und seiner auf eine Referenzgrösse R bezogenen ersten Durchgangshäufigkeit N und deren Schwankungsbreite dN innerhalb eines vorgegebenen Zeitintervalls beobachtet, wobei die Durchgangshäufigkeit N aus Einzeldurchgangshäufigkeiten ermittelt wird und wobei die Schwankungsbreite durch die maximale Abweichung der Einzeldurchgangshäufigkeiten bestimmt ist. Zu diesem Zweck wird das aufgenommene Signal bzw. Signalgemisch Z (t) zunächst verstärkt, dann mittels eines Bandpassfilters gefiltert und anschliessend einer Analog/Digital-Wandlung unterzogen, wodurch sich die genannte Eingangsgrösse E ergibt, vergleiche Figur 1. Aus den betreffenden gewonnenen Grössen werden Hilfsgrössen S1, N2 abgeleitet, vergleiche Figur 3.As already stated at the outset, the method according to the present invention uses their amplitude behavior as a distinguishing criterion between a signal of interest and the background signal or background signal mixture. For this purpose, in a first step, a recorded and then preprocessed signal or signal mixture, namely an input variable E, is observed within a predetermined time interval with regard to its mean amplitude A and its first frequency of passage N, which is based on a reference variable R, and its fluctuation range dN, the frequency of passage N being off Individual passage frequencies is determined and the fluctuation range is determined by the maximum deviation of the individual passage frequencies. For this purpose, the recorded signal or signal mixture Z (t) is first amplified, then filtered by means of a bandpass filter and then subjected to an analog / digital conversion, as a result of which the input variable E is obtained, see FIG. 1 Auxiliary variables S1, N2 derived, compare FIG. 3.
In einem zweiten Schritt innerhalb eines für eine ausreichende Auflösung benötigten Zeitrasters wird die aktuelle Durchgangshäufigkeit N1 bezogen auf die Referenzgrösse R bestimmt. In Abhängigkeit von der beobachteten abgeleiteten Durchgangshäufigkeit N2 mit ihrer Schwankungsbreite dN und der aktuellen Durchgangshäufigkeit N1 wird eine der zuvor abgeleiteten Hilfsgrössen S1 oder S2 einer Bewertungsgrösse S zugeordnet. Anhand dieser Bewertungsgrösse S wird die aktuelle Eingangsgrösse E gemessen. Dazu wird eine von der Lage der Eingangsgrösse E relativ zu der Bewertungsgrösse S abhängige Operation 01 durchgeführt. Aufgrund der Art des interessierenden Signals werden zwei Grenzwerte UG, OG1 festgelegt. Das Ergebnis der Operation 01 wird durch den ersten Grenzwert nach unten begrenzt. Bei Erreichen des zweiten, oberen Grenzwertes OG1 wird das Vorhandensein eines interessierenden Signals erkannt. Der exakte Signalbeginn SB liegt dabei um einen definierten Zeitabschnitt vor dem betreffenden Erkennungszeitpunkt ZE1, vergleiche Figur 4 und Figur 5.In a second step within a time grid required for a sufficient resolution, the current frequency of passage N1 is determined in relation to the reference variable R. Depending on the observed derived passage frequency N2 with its fluctuation range dN and the current passage frequency N1, one of the previously derived auxiliary variables S1 or S2 is assigned to an evaluation variable S. The current input variable E is measured on the basis of this evaluation variable S. For this purpose, an operation 01 which is dependent on the position of the input variable E relative to the evaluation variable S is carried out. Two limit values UG, OG1 are defined on the basis of the type of signal of interest. The result of operation 01 is limited by the first limit. When the second, upper limit value OG1 is reached, the presence of a signal of interest is recognized. The exact start of the signal SB is a defined time period ahead of the relevant orken time of ZE1, compare Figure 4 and Figure 5.
In einem dritten Schritt wird durch eine weitere Operation 02 die Lage der Eingangsgrösse E relativ zu der Bewertungsgrösse S in der Art ausgewertet, dass bei Erreichen eines zweiten aufgrund der Art des interessierenden Signals zuvor festgelegten Grenzwertes OG2 das Nichtvorhandensein des in dem zweiten Schritt erfassten interessierenden Signals festgestellt wird. Das exakte Signalende SE liegt um einen definierten Zeitabschnitt vor dem betreffenden Erkennungszeitpunkt ZE2, vergleiche Figur und Figur 7.In a third step, the position of the input variable E relative to the evaluation variable S is evaluated by a further operation 02 in such a way that when a second limit value OG2 predetermined based on the type of the signal of interest is reached, the absence of the signal of interest acquired in the second step is present is detected. The exact end of the signal SE is a defined time period before the relevant detection time ZE2, see FIG. 7.
Gemäss einer vorteilhaften Weiterbildung der Erfindung ist die genannte Operation 01 als ein Integrationsvorgang vorgesehen.According to an advantageous development of the invention, said operation 01 is provided as an integration process.
Der exakte Signalbeginn SB ist durch die zeitliche Position des letzten Wertes des Integrationsergebnisses gleich dem unteren Grenzwert UG vor dem betreffenden Erkennungszeitpunkt ZE1 festgelegt.The exact start of the signal SB is determined by the temporal position of the last value of the integration result equal to the lower limit value UG before the relevant detection time ZE1.
Vorteilhafterweise kann der erste Schritt, wie er zuvor beschrieben wurde, für den Fall wiederholt werden, dass die Eingangsgrösse E eine dem Hintergrundsignalgemisch angepasste Schwelle überschreitet. Ausserdem ist zweckmässigerweise zwischen dem ersten Schritt und dem zweiten Schritt eine Karenzzeit eingeschoben.The first step, as described above, can advantageously be repeated in the event that the input variable E exceeds a threshold adapted to the background signal mixture. In addition, a waiting period is expediently inserted between the first step and the second step.
Die zuvor genannten Hilfsgrössen sind wie folgt definiert:
Die Bewertungsgrösse S ist wie folgt definiert:
Die erfindungsgemässen Verarbeitungs- und Bewertungsvorgänge können mittels digitaler Schaltkreise durchgeführt werden, sind jedoch zweckmässigerweise mittels eines Mikroprozessors und entsprechender Programme dafür durchzuführen.The processing and evaluation processes according to the invention can be carried out by means of digital circuits, but are expediently to be carried out by means of a microprocessor and corresponding programs therefor.
Figur 2 zeigt, wie bereits erläutert, ein Ablaufdiagramm für eine Wortgrenzendetektion. In diesem Ablaufdiagramm sind die genannten Schritte, nämlich der erste Schritt, der zweite Schritt und der dritte Schritt nochmals verdeutlichend dargestellt.As already explained, FIG. 2 shows a flow diagram for a word boundary detection. The steps mentioned, namely the first step, the second step and the third step, are illustrated again clearly in this flowchart.
Figur 8 zeigt, wie bereits eingangs erläutert, eine Diagrammdarstellung für eine gesamte Wortgrenzenerkennung des gesprochenen Wortes «Stop», wobei in dem oberen Diagrammteil ein Schwingungsverlauf des betreffenden Zeitsignals mit zugeordneten oberen und unteren Schwellwerten, dem mittleren Teil des Diagramms ein erzeugtes digitales Anzeigesignal für den Zustand «interessierendes Wort liegt vor» und in dem unteren Teil der Diagrammdarstellung der Vorgang der Wortbeginn- und Wortende-Erkennung gezeigt ist.FIG. 8 shows, as already explained at the beginning, a diagram for an entire word boundary recognition of the spoken word “stop”, in the upper part of the diagram a waveform of the relevant time signal with assigned upper and lower threshold values, and the middle part of the diagram a generated digital display signal for the State "word of interest is present" and the process of word start and word end recognition is shown in the lower part of the diagram.
Das erfindungsgemässe Verfahren bietet im Zusammenhang mit dem Erkennen der Grenzen von gesprochenen Wörtern folgende Vorteile:
- 1. Signale mit dem Frequenzverhalten des Umweltgeräusches werden mit einer hohen Schwelle verglichen, können also auch dann, wenn sie lauter werden, nur in seltenen Fällen zu einer fälschlichen «Wortbeginn»-Meidung führen.
- 2. Signale mit anderem Frequenzverhalten werden mit einer niedrigen Schwelle verglichen, das heisst, sie können auch bei kleiner Amplitude erkannt werden.
- 3. Bei Signalen, deren überwiegender Anteil unter der jeweiligen Schwelle liegt, kann das Integral über die «geclippten» Werte einen bestimmten vorgegebenen Betrag nicht erreichen. Dadurch werden Störungen wie etwa das Geräusch einer schlagenden Tür, Fabrikmaschinenlärm usw. oder schwacher Signale, wie Sprache oder Musik, aus weiterer Entfernung unterdrückt.
- 4. Durch das integrierte Verfahren werden auch Sprachsignale mit schwachen Anfangsfrikativen korrekt detektiert.
- 1. Signals with the frequency behavior of the environmental noise are compared to a high threshold, so even if they become louder, they can rarely lead to an erroneous “beginning of words” avoidance.
- 2. Signals with different frequency behavior are compared with a low threshold, which means that they can be recognized even with a small amplitude.
- 3. In the case of signals whose predominant share lies below the respective threshold, the integral cannot reach a certain predetermined amount via the “clipped” values. This suppresses interference such as the sound of a door banging, factory machine noise etc. or weak signals such as speech or music from a distance.
- 4. The integrated method also correctly detects speech signals with weak initial fricatives.
In den meisten Fällen wird das Umweltgeräusch dominierende Frequenzanteile im Bereich der Vokal-Formanten aufweisen. Diese Formanten haben jedoch meist relativ grosse Amplituden, so dass sie auch bei einer hohen Schwelle detektiert werden können.In most cases, the environmental noise will have dominant frequency components in the area of the vowel formants. However, these formants mostly have relatively large amplitudes, so that they can also be detected at a high threshold.
Die durch die Vorverarbeitung (Bandpassfilterung) stark bedämpften stimmlosen Laute mit einem grossen Anteil hoher Frequenzen unterscheiden sich dagegen meist nur durch ihre Nulldurchgangsrate von der Umgebung. Dies wird durch die Wahl der niedrigen Schwelle berücksichtigt.The unvoiced sounds with a large proportion of high frequencies, which are strongly attenuated by the preprocessing (bandpass filtering), on the other hand, differ from the surroundings only in their zero crossing rate. This is taken into account by the choice of the low threshold.
Das erfindungsgemässe Verfahren ist selbstverständlich nicht auf die beschriebenen Ausführungsbeispiele beschränkt. So kann es beispielsweise auch für Überwachungszwecke zum Auffinden bestimmter typischer Signalverläufe innerhalb eines Signalgemisches, beispielsweise für Funküberwachungszwecke, verwendet werden.The method according to the invention is of course not limited to the exemplary embodiments described. For example, it can also be used for monitoring purposes to find certain typical signal profiles within a signal mixture, for example for radio monitoring purposes.
Claims (11)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT85103259T ATE40235T1 (en) | 1984-03-28 | 1985-03-20 | METHOD OF DETECTING THE BOUNDARIES OF SIGNALS OCCURRING OVER A BACKGROUND SIGNAL COMPOSITION. |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19843411485 DE3411485A1 (en) | 1984-03-28 | 1984-03-28 | METHOD FOR DETECTING THE LIMITS OF SIGNALS THAT APPEAR IN MIXTURE BEFORE A BACKGROUND SIGNAL MIXTURE |
| DE3411485 | 1984-03-28 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0161423A1 EP0161423A1 (en) | 1985-11-21 |
| EP0161423B1 true EP0161423B1 (en) | 1989-01-18 |
Family
ID=6231908
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP85103259A Expired EP0161423B1 (en) | 1984-03-28 | 1985-03-20 | Method for determining the boundaries of a signal mixed with background noise |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0161423B1 (en) |
| JP (1) | JPS60218700A (en) |
| AT (1) | ATE40235T1 (en) |
| DE (2) | DE3411485A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0537804B1 (en) * | 1987-01-16 | 1997-07-23 | Sharp Kabushiki Kaisha | Speech recording apparatus with compression of soundless sections |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1772633U (en) | 1958-06-26 | 1958-08-21 | No Sag Drahtfedern Gmbh | SPRING FOR UPHOLSTERY FRAME. |
| GB1012765A (en) | 1964-03-06 | 1965-12-08 | Standard Telephones Cables Ltd | Apparatus for the analysis of waveforms |
| GB1495389A (en) | 1974-01-31 | 1977-12-14 | Atomic Energy Authority Uk | Apparatus for providing time reference signals |
| US4032710A (en) * | 1975-03-10 | 1977-06-28 | Threshold Technology, Inc. | Word boundary detector for speech recognition equipment |
| FR2402971A1 (en) | 1977-09-09 | 1979-04-06 | Onera (Off Nat Aerospatiale) | SYNTACTIC EXTRACTOR OF EVOLVING SIGNALS AND EXTRACTION PROCESS |
| DE3003556C2 (en) | 1980-02-01 | 1984-12-06 | Dornier Gmbh, 7990 Friedrichshafen | Method and device for determining a useful signal from a band-limited signal superimposed with interference signals |
| US4388495A (en) | 1981-05-01 | 1983-06-14 | Interstate Electronics Corporation | Speech recognition microcomputer |
| DE3207556C2 (en) | 1982-03-03 | 1983-12-22 | Vierling, Oskar, Prof. Dr.Phil.Habil., 8553 Ebermannstadt | Arrangement for measuring the characteristic times of pulses and pulse series |
-
1984
- 1984-03-28 DE DE19843411485 patent/DE3411485A1/en not_active Withdrawn
-
1985
- 1985-03-20 EP EP85103259A patent/EP0161423B1/en not_active Expired
- 1985-03-20 DE DE8585103259T patent/DE3567757D1/en not_active Expired
- 1985-03-20 AT AT85103259T patent/ATE40235T1/en not_active IP Right Cessation
- 1985-03-27 JP JP60063154A patent/JPS60218700A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| DE3567757D1 (en) | 1989-02-23 |
| JPS60218700A (en) | 1985-11-01 |
| ATE40235T1 (en) | 1989-02-15 |
| DE3411485A1 (en) | 1985-10-03 |
| EP0161423A1 (en) | 1985-11-21 |
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