WO2018077800A1 - Signalisation acoustique - Google Patents

Signalisation acoustique Download PDF

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Publication number
WO2018077800A1
WO2018077800A1 PCT/EP2017/076999 EP2017076999W WO2018077800A1 WO 2018077800 A1 WO2018077800 A1 WO 2018077800A1 EP 2017076999 W EP2017076999 W EP 2017076999W WO 2018077800 A1 WO2018077800 A1 WO 2018077800A1
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WO
WIPO (PCT)
Prior art keywords
signal
signaling
signaling tone
sound
tone signal
Prior art date
Application number
PCT/EP2017/076999
Other languages
English (en)
Inventor
Peter Perzlmaier
Thomas Hill
Original Assignee
Harman Becker Automotive Systems Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Harman Becker Automotive Systems Gmbh filed Critical Harman Becker Automotive Systems Gmbh
Publication of WO2018077800A1 publication Critical patent/WO2018077800A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R29/00—Monitoring arrangements; Testing arrangements
    • H04R29/001—Monitoring arrangements; Testing arrangements for loudspeakers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00—Circuits for transducers, loudspeakers or microphones
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K9/00—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers
    • G10K9/12—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated
    • G10K9/13—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated using electromagnetic driving means
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R2430/00—Signal processing covered by H04R, not provided for in its groups
    • H04R2430/01—Aspects of volume control, not necessarily automatic, in sound systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R2499/00—Aspects covered by H04R or H04S not otherwise provided for in their subgroups
    • H04R2499/10—General applications
    • H04R2499/13—Acoustic transducers and sound field adaptation in vehicles

Definitions

  • the disclosure relates to a system and method (generally referred to as a "system") for acoustic signaling.
  • Signaling sounds such as informational, warning or alarm tones
  • Signaling sounds are used in many different types of applications in which one or more recipients need to be put on alert or warned acoustically, e.g., upon detection of danger or emergency situations such as fire, burglary or unauthorized entry, or also when monitoring transit systems, engines or vehicles.
  • Safety systems commonly record specific events with a sensor, and upon evaluation may generate appropriate signaling sounds by way of acoustic signaling systems.
  • a multiplicity of informational, warning and alarm tones is generated during vehicle operation. Since vehicle drivers rely on the dependable operation of such driver assistance systems, it is essential that their acoustic signaling systems operate without fail. Therefore, there is a desire for increasing the reliability of acoustic signaling.
  • An acoustic signaling system includes a signal source configured to provide a signaling tone signal; a signal processing block configured to process the signaling tone signal to provide a processed signaling tone signal; and an electro-acoustic reproduction block configured to convert the processed signaling tone signal into signaling sound at a listening position.
  • the acoustic signaling system further includes a correlator configured to determine a correlation coefficient from a signal representative of the signaling tone signal and a signal representative of the signaling sound, the correlation coefficient being representative of the correlation of the signaling tone signal and the signaling sound; and a diagnosis block configured to evaluate the correlation coefficient and to output a diagnosis signal if the correlation coefficient is below a predetermined threshold.
  • An acoustic signaling method includes providing a signaling tone signal; processing the signaling tone signal to provide a processed signaling tone signal; and converting the processed signaling tone signal into signaling sound at a listening position.
  • the method further includes determining a correlation coefficient from a signal representative of the signaling tone signal and a signal representative of the signaling sound, the correlation coefficient being representative of the correlation of the signaling tone signal and the signaling sound; and evaluating the correlation coefficient and outputting a diagnosis signal if the correlation coefficient is below a predetermined threshold.
  • Figure 1 is a schematic diagram illustrating an exemplary acoustic signaling system having a simple monitoring structure
  • Figure 2 is a schematic diagram illustrating another exemplary acoustic signaling system having a complex monitoring structure
  • Figure 3 is a diagram illustrating an exemplary method for monitoring an acoustic signaling system
  • Figure 4 is a schematic diagram illustrating an exemplary cross-correlator.
  • an exemplary acoustic signaling system includes a signal generation block 101, a signal processing block 102 connected downstream of the signal generation block 101, and a signal reproduction block 103 connected downstream of the signal processing block 102.
  • a cross-correlator block 104 receives, on the one hand, a signaling tone signal x which is an input signal of signal processing block 102, and, on the other hand, a processed signaling tone signal y which is an output signal of signal processing unit 102, or a signal representative of the processed signaling tone signal y.
  • the cross-correlator block 104 determines a correlation coefficient z representative of the degree of correlation between the signaling tone signal x and the processed signaling tone signal y or a signal representative of the processed signaling tone signal y.
  • the signaling tone signal x is input into the cross-correlator block 104 together with the processed signaling tone signal y or, alternatively, with a processed signaling tone signal s' which is provided by an acoustic sensor 105.
  • the acoustic sensor 105 picks up signaling sound s that is generated by the signal reproduction block 103 based on the processed signaling signal y, and converts the picked up signaling sound s into the processed signaling tone signal s' both of which are representative of the processed signaling tone signal y and vice versa.
  • the correlation coefficient z from cross-correlator block 104 is input into a diagnosis block 106 which evaluates the cross-correlation coefficient z and outputs a diagnosis signal d if the cross-correlation coefficient z is below a predetermined threshold v. Further, diagnosis block 106 may control, dependent on the correlation coefficient z, at least one of the signal generation block 101 and the signal processing block 102 by way of a control signal c.
  • the signal generation block 101 e.g., a tone signal generator, provides one or more signaling tone signals and may be triggered with a trigger signal t, which, as the case may be, can also be used to select one of the tone signals.
  • Different signaling tone signals may be used in connection with different alert, warning or emergency situations, for example.
  • a signal generator any other appropriate signal source may be employed such as a media player, synthesizer, memory with stored sound samples etc.
  • Simple sound generators may include oscillators or multi- vibrators, which generate single frequency tones or multi-frequency tones without or with a certain temporal structure such as modulated tones, on-and-off switched tones, swelling tones, wobbling tones etc.
  • the signal processing block 102 may employ any type of signal processing such as, for example, at least one of equalizing the signaling tone signal x, mixing the signaling tone signal x with another signal, controlling the volume of the signaling tone signal (e.g. by way of a controllable amplifier or an attenuator), modulating the signaling tone signal x (e.g., to change or adjust its temporal structure), delaying the signaling tone signal, and limiting the signaling tone signal.
  • the signal generator block 101 as well as the signal processing block 102 may be implemented in at least one of analog hardware, digital hardware, and software executed by a processor.
  • the signal reproduction block 103 may include one or more transducers, e.g., loudspeakers, and optionally one or more amplifiers to drive the transducer(s).
  • the signal reproduction block 103 converts the processed signaling tone signals y, which are in the electrical domain, into the signaling sound s which is in the acoustic domain.
  • the signal reproduction block 103 is designed to supply sufficient acoustic energy to a listening position so that the signaling sound is audible at the listening position under normal operating conditions of the signaling system.
  • Cross-correlator 104 determines the correlation coefficient z from the signaling tone signal x and the processed signaling tone signal y (alternatively the processed signaling tone signal s'). The correlation may be determined according to the below equations.
  • the cross-correlation represented by ⁇ ( ⁇ ) is defined as: wherein t is a time and ⁇ is a time delay.
  • n - ⁇ wherein n and m are discrete points in time.
  • the cross-correlation coefficient for continuous signals may be calculated according to: convex, y)
  • the cross-correlation coefficient z for discrete signals may be calculated accordingly. However, any other appropriate approach or method may be used to calculate, estimate or approximate the correlation between x and y. In the present example, the cross-correlation coefficient may be between and including "1", which represents full correlation, and "0" which means no correlation.
  • the acoustic sensor 105 is configured to pick up (total) sound at or in the vicinity of a listening position and may include one or more microphones (e.g., an array of microphones) and optionally appropriate circuitry for evaluating signals provided by the microphone(s) such as, for example, at least one of amplifiers, filters, and beamforming circuits.
  • the microphone(s) may be operated in combination with, e.g., power supplies, preamplifiers, impedance matching circuits, filters, etc.
  • Diagnosis block 106 may, for example, compare the correlation coefficient z with the threshold v and, if the correlation coefficient z undercuts the threshold v, the diagnosis signal d, which indicates a malfunction in the acoustic signaling system, is generated.
  • the diagnosis block 106 may further generate the control signal c which may control, to a certain extent, at least one of the signal generator block lOland the signal processing block 102.
  • the diagnosis block 106 may, at least one of, reset at least one of the signal generator block 101 and signal processing block 102, retrigger (restart) the signal generator block 101, and adjust an equalizer setting and/or a volume setting in the signal processing block 102.
  • the diagnosis block 106 may perform further diagnostic functions on a sporadic or regular basis. Further exemplary diagnostic functions are described below in connection with Figure 2.
  • a signal source e.g., an audio player block 201
  • the control block 203 receives via a control and/or data bus CAN (e.g., a CAN bus) instructions which are processed by the control block 203 in order to generate a control signal M ctr for the memory block 202, a control signal AP ctr for the audio player block 201, and other control signals as described further below.
  • CAN e.g., a CAN bus
  • the audio player block 201 may reproduce any appropriate audio file such as, for example, WAV files, MP3 files, AAC files, PCM files, etc.
  • the audio files that are to be played and that are stored in the memory 202 are sent to the audio player 201 upon initiation by the control block 203.
  • the control block 203 controls the audio player 201 to receive the selected audio file and to reproduce it.
  • the control block 203 may also adjust, by way of control signals EQ ctr, (filter) settings of an equalizer block 204 connected downstream of the audio player 201.
  • the control block 203 may further control, by way of a control signal V ctr, a volume control block 205 which is connected downstream of the equalizer block 204 and which may attenuate or amplify signals received from the equalizer block 204.
  • Signals output by the volume control block 205 are supplied to an audio mixing block 206 which further receives useful audio signals from a second audio source 213.
  • the two signals received are mixed (e.g., summed up) to supply a respective audio signal via an amplifier 207 to a loudspeaker 208.
  • the second audio source 207 may be controlled by the control block 203 and may be an entertainment or navigation system of a vehicle that may provide signals such as traffic messages, route information, etc.
  • a correlator block 209 receives the output signal of the volume control block 205 and the output signal of the audio mixing block 206.
  • the correlation block 209 which may perform a cross-correlation operation, issues a correlation coefficient corr coef to a diagnosis block 210.
  • the diagnosis block 210 may further receive instructions via control and/or data bus CAN and provide a control signal C ctr to the control block 203.
  • the diagnosis block 210 may further receive a diagnosis signal CRC diagn from the memory 202, a diagnosis signal AP diagn from the audio player block 201, a diagnosis signal EQ diagn from the equalizer block 204, and a diagnosis signal V diagn from the volume control block 205.
  • the diagnosis block 210 may receive an amplifier diagnosis signal Amp diagn from the amplifier 207, a loudspeaker diagnosis signal Lpr diagn from the loudspeaker 208. If an optional acoustic sensor for picking up (total) sound at or in the vicinity of a listening position, e.g., a microphone 211 and a preamplifier 212, is employed, a microphone diagnosis signal Mic diagn may also be supplied to the diagnosis block 210. Beside the control signal C ctr the diagnosis block 210 may issue a diagnostic trouble code DTC which indicates a malfunction of the system and provides an identification of the type of malfunction.
  • a diagnostic trouble code DTC which indicates a malfunction of the system and provides an identification of the type of malfunction.
  • the diagnosis of the memory 202 may include a cyclic redundancy check (CRC) which may, for example, check whether audio files to be played are corrupted.
  • CRC cyclic redundancy check
  • the diagnosis of the audio player 201 may include determining the status of the audio file, e.g. as in order (OK) or not in order (NOK) at start-up, and may include a playback response check (OK, NOK) during operation of the audio player 201.
  • an equalization check may be performed which may include checking the equalizer status and operability at start-up, and checking the equalizer settings, continuously or on a regular basis, during operation of equalizer block 204.
  • Checking the equalizer settings may include a plausibility check at start-up as well as checking the signal flow version and the audio level received from the audio equalization block 204 by comparing them against expected versions and levels.
  • An optional check of the volume control block 205 may include a plausibility check of the volume settings at start-up and/or (continuously or on a regular basis) during operation.
  • the diagnosis of the amplifier 207 may include a continuous check of the power supply of the amplifier, and monitoring the output of the amplifier 207.
  • diagnosis of the loudspeaker 208 may include a direct current (DC) check at start-up and a continued alternating current (AC) check during operation to detect, e.g., a line break or a short circuit.
  • DC direct current
  • AC alternating current
  • a respective diagnosis may be performed, which may include a DC microphone check once at start-up and an AC check continuously or on a regular basis during operation.
  • the correlation coefficient Corr coef determined by the correlator block 209 may be compared with at least one threshold value in diagnosis block 210.
  • the correlation coefficient Corr coef may be verified against two threshold values, a minimum correlation threshold Corr min and a maximum correlation threshold Corr max.
  • the correlation coefficient Corr Coef may be determined, e.g., calculated, after the respective audio file has been completely played.
  • the two thresholds Corr min and Corr max define a valid range within which the correlation coefficient Corr coef should be during normal operation. The range may be adjustable or fixed.
  • the diagnosis block 210 evaluates the results of each particular diagnosis process and issues the diagnostic trouble code DTC that indicates and optionally identifies a malfunction.
  • the diagnosis block 210 may generate the control signal C ctr which may control, via the control block 203, the audio player block 201, the memory block 202, the equalizer block 204, and the volume control block 205.
  • a signaling tone signal is provided (procedure 301) and the signaling tone signal is processed to provide a processed signaling tone signal (procedure 302).
  • the processed signaling tone signal is converted into signaling sound at a listening position (procedure 303).
  • a correlation coefficient is determined from a signal representative of the signaling tone signal and a signal representative of the signaling sound (procedure 304), wherein the correlation coefficient is representative of the correlation of the signaling tone signal and the signaling sound.
  • the correlation coefficient is evaluated in order to output a diagnosis signal if the correlation coefficient is below a predetermined threshold (procedure 305), i.e., if there is little or no correlation.
  • One option is to use the processed signaling tone signal as a signal representative of the signaling sound.
  • sound may be picked up at or in the vicinity of the listening position and converted into a (total) sound signal which can be used as the signal representative of the signaling sound.
  • at least one of signaling tone signal and processed signaling tone signal may be controlled dependent on the correlation coefficient.
  • Signal processing may include combining the signaling tone signal and a useful signal and/or may include controlling volume by attenuating the signaling tone signal dependent on a volume control signal. Controlling the volume may be dependent on the total sound signal, and may further include checking initially, repeatedly or continuously at least one of converting the processed signaling tone signal into signaling sound, picking up sound, providing the signaling tone signal, and signal processing. Determining the correlation coefficient may further include performing a cross-correlation calculation.
  • the signal representative of the processed signaling tone signal may be derived from the total sound signal or from the processed signaling tone.
  • an exemplary structure of a simple cross-correlator block includes a delay line 401 that is formed by a multiplicity of series-connected delays 402, each having a delay time ⁇ .
  • the delay line 401 is supplied with one input signal, e.g., signal x(t) or y(t), and includes taps between the delays 402, at the beginning of the delay line 401 and at the end of the delay line 401 to provide a multiplicity of tap signals.
  • Each tap signal is multiplied with another input signal, e.g., signal y(t) or x(t), by way of a multiplicity of multipliers 403 to provide a multiplicity of intermediate signals which are summed up by a summer 404 to form a sum signal.
  • the sum signal is weighted (multiplied) in a multiplier 405 with a coefficient K which may be, for example, 1/ ⁇ ⁇ ⁇ ⁇ .
  • the output signal of the multiplier 405 is the correlation coefficient z.
  • the exemplary systems and methods described above in connection with Figures 1-4 may be used in a variety of applications such as, e.g., automotive applications in which a reliable acoustic signaling is vital.
  • the exemplary systems and methods may be employed to alert a driver of when an autonomous cruise control (ACC) system or any other safety-relevant system including an advanced driver assistance system (ADAS) has become unavailable or issues an alarm.
  • ACC autonomous cruise control
  • ADAS advanced driver assistance system
  • references to "one embodiment” or “one example” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.
  • the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements or a particular positional order on their objects.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Circuit For Audible Band Transducer (AREA)

Abstract

L'invention concerne un système et un procédé de signalisation acoustique, consistant à : fournir un signal tonal de signalisation ; traiter le signal tonal de signalisation pour fournir un signal tonal de signalisation traité ; et convertir le signal tonal de signalisation traité en un son de signalisation à une position d'écoute. Le système et le procédé consistent en outre à : déterminer un coefficient de corrélation à partir d'un signal représentatif du signal tonal de signalisation et d'un signal représentatif du son de signalisation, le coefficient de corrélation étant représentatif de la corrélation du signal tonal de signalisation et du son de signalisation ; évaluer le coefficient de corrélation ; et émettre un signal de diagnostic si le coefficient de corrélation est inférieur à un seuil prédéterminé.
PCT/EP2017/076999 2016-10-27 2017-10-23 Signalisation acoustique WO2018077800A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP16195977.0 2016-10-27
EP16195977 2016-10-27

Publications (1)

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WO2018077800A1 true WO2018077800A1 (fr) 2018-05-03

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PCT/EP2017/076999 WO2018077800A1 (fr) 2016-10-27 2017-10-23 Signalisation acoustique

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109618273A (zh) * 2018-12-29 2019-04-12 北京声智科技有限公司 麦克风质检的装置及方法
EP3694230A1 (fr) * 2019-02-08 2020-08-12 Ningbo Geely Automobile Research & Development Co. Ltd. Diagnostic audio dans un véhicule

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6639989B1 (en) * 1998-09-25 2003-10-28 Nokia Display Products Oy Method for loudness calibration of a multichannel sound systems and a multichannel sound system
US20100074451A1 (en) * 2008-09-19 2010-03-25 Personics Holdings Inc. Acoustic sealing analysis system
US20100135118A1 (en) * 2005-06-09 2010-06-03 Koninklijke Philips Electronics, N.V. Method of and system for determining distances between loudspeakers
US20120140936A1 (en) * 2009-08-03 2012-06-07 Imax Corporation Systems and Methods for Monitoring Cinema Loudspeakers and Compensating for Quality Problems
US20140294201A1 (en) * 2011-07-28 2014-10-02 Thomson Licensing Audio calibration system and method
US20150256944A1 (en) * 2012-10-24 2015-09-10 Kyocera Corporation Vibration pickup device, vibration measurement device, measurement system, and measurement method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6639989B1 (en) * 1998-09-25 2003-10-28 Nokia Display Products Oy Method for loudness calibration of a multichannel sound systems and a multichannel sound system
US20100135118A1 (en) * 2005-06-09 2010-06-03 Koninklijke Philips Electronics, N.V. Method of and system for determining distances between loudspeakers
US20100074451A1 (en) * 2008-09-19 2010-03-25 Personics Holdings Inc. Acoustic sealing analysis system
US20120140936A1 (en) * 2009-08-03 2012-06-07 Imax Corporation Systems and Methods for Monitoring Cinema Loudspeakers and Compensating for Quality Problems
US20140294201A1 (en) * 2011-07-28 2014-10-02 Thomson Licensing Audio calibration system and method
US20150256944A1 (en) * 2012-10-24 2015-09-10 Kyocera Corporation Vibration pickup device, vibration measurement device, measurement system, and measurement method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109618273A (zh) * 2018-12-29 2019-04-12 北京声智科技有限公司 麦克风质检的装置及方法
EP3694230A1 (fr) * 2019-02-08 2020-08-12 Ningbo Geely Automobile Research & Development Co. Ltd. Diagnostic audio dans un véhicule

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