Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04S—STEREOPHONIC SYSTEMS 
  • H04S7/00—Indicating arrangements; Control arrangements, e.g. balance control
  • H04S7/30—Control circuits for electronic adaptation of the sound field
  • H04S7/302—Electronic adaptation of stereophonic sound system to listener position or orientation
  • H04S7/303—Tracking of listener position or orientation
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
  • H04R1/00—Details of transducers, loudspeakers or microphones
  • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
  • H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
  • H04R1/323—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only for loudspeakers
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
  • H04R1/00—Details of transducers, loudspeakers or microphones
  • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
  • H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
  • H04R1/40—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers
  • H04R1/403—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers loud-speakers
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
  • H04R1/00—Details of transducers, loudspeakers or microphones
  • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
  • H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
  • H04R1/40—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers
  • H04R1/406—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers microphones
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
  • H04R3/00—Circuits for transducers
  • H04R3/005—Circuits for transducers for combining the signals of two or more microphones
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
  • H04R3/00—Circuits for transducers
  • H04R3/12—Circuits for transducers for distributing signals to two or more loudspeakers
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
  • H04R2410/00—Microphones
  • H04R2410/05—Noise reduction with a separate noise microphone
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; 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 present invention relates in general to the electronic industry.
• the present invention relates to an electronic audio communication system for creating isolated audio communication zones within a closed environment such as a land or air transport means, and an audio communication method thereof.
• the microphones are used to acquire the voice of the occupants of the same vehicle and the loudspeakers are used to reproduce sound signals representative of a musical track and/or of a voice of an external user, during a voice call between an occupant of the vehicle and the user.
• US 2020/0413194 A1 discloses an audio system 30 for a headrest 12 of a seat of a vehicle, wherein the audio system 30 comprises one or more loudspeakers 32 and one or more microphones 34, which are integrated into the headrest 12; the audio system 30 allows to decrease (or even cancel) an echo caused by the loudspeaker 32 of the headrest and/or by a loudspeaker 40 of the passenger compartment, for example in case music is present within the passenger compartment while a user 22 is performing a phone call with a remote caller.
• the present invention relates to an electronic audio communication system for creating isolated audio communication zones within a closed environment as defined in the appended claim 1 and the preferred embodiments thereof described in the dependent claims from 2 to 7.
• FIG. 1 a block diagram of an electronic communication system 100 for creating isolated audio communication zones within a closed environment according to an embodiment of the invention is shown.
• the electronic system 100 is positioned within the closed environment in which fixed stations can be defined and in which there are three occupants, each positioned in a respective fixed station associated with a corresponding isolated audio communication zone.
• the closed environment can be, for example:
• isolated audio communication zone (or “private audio communication zone”) is intended to mean that an occupant is positioned (e.g., seated) at a station in an audio communication zone within a closed environment and is capable of exchanging voice messages with a remote user 30 positioned externally with respect to the closed environment, or is capable of exchanging voice messages with other occupants at other stations within the closed environment or with a voice assistant, so as to minimize the interfering noise generated by occupants of the closed environment positioned in audio communication zones (i.e., stations) different from that of the occupant who is speaking and so as to minimize the environmental noise present within the closed environment.
• audio communication zones i.e., stations
• the electronic system 100 comprises a processing unit 50, a user interface unit 40, a first local unit 1, a second local unit 10 and a third local unit 20.
• the electronic system 100 is configured to perform a voice call with the remote user 30 external to the closed environment, wherein each of the three occupants may speak with the remote user 30, both a single occupant, and two occupants simultaneously, and three occupants simultaneously.
• the first and second microphones 2-1, 2-2 of the first local unit 1 are such to also acquire the voice of the driver (when the driver is speaking with the remote user 30 or with the first or second passenger), but the acoustic signal of the voice of the driver (who is speaking with the remote user 30 or with the first or second passenger) acquired by the first and/or second microphone 2-1, 2-2 is not considered as a signal useful for the purposes of voice communication with the remote user 30 (or with the first or second passenger), i.e. it is considered as an interfering noise, since the acoustic signal of the voice of the driver acquired by the first environmental microphone 5-1 will be considered useful for the purposes of voice communication with the remote user 30 (or with the first or second passenger).
• the user interface unit 40 comprises a voice assistant configured to perform a voice conversation with an occupant within the closed environment.
• the fifth and sixth microphones 23-1, 23-2 of the third local unit 20 are such as to also acquire the voice of the second passenger, but the acoustic signal of the voice of the second passenger (who is speaking with the remote user 30 or with the first passenger) acquired by the fifth and/or sixth microphone(s) 23-1, 23-2 is not considered as a signal useful for the purposes of voice communication with the remote user 30 (or with the driver or first passenger), i.e. it is considered as an interfering noise, as the acoustic signal of the voice of the second passenger acquired by the third environmental microphone 5-3 will be considered useful for the purposes of voice communication with the remote user 30 (or with the driver or first passenger).
• the first, second and third environmental microphones 5-1, 5-2, 5-3 are configured to acquire a respective echo of the voice of the remote user 30 who is speaking, wherein each of the echoes is generated due to the loudspeakers 3-1 and/or 3-2 of the first local unit emitting the acoustic signal of the voice of the remote user 30 who is speaking, said emitted acoustic signal of the voice of the remote user 30 being then acquired by the first, second and third environmental microphones 5-1, 5-2, 5-3, and wherein the intensity and the characteristics of the echoes acquired at the first, second and third environmental microphones 5-1, 5-2, 5-3 are different from each other; furthermore, in the event that the loudspeakers 12-1, 12-2, 22-1, 22-2 of the second and/or third local unit(s) 10, 20 emit respective acoustic signals (for example, of a music track and/or of a second and third occupants who are speaking with each other or a
• the first and second microphones 2-1, 2-2 of the first local unit 1 are configured to acquire an interfering noise of the voice of the other occupants who are speaking by themselves or with each other and/or acquire an environmental noise present within the closed environment.
• the processing unit 50 further comprises a second input terminal adapted to receive from the second environmental microphone 5-2 a second occupant signal S2_oc carrying a second acoustic signal of the acquired voice of the first and/or second and/or third occupant(s) and possibly carrying one or more echoes caused by the acoustic signal emitted by the loudspeakers 3-1, 3-2, 12-1, 12-2, 22-1, 22-2 of the first, second and third local units 1, 10, 20; the processing unit 50 further comprises a third input terminal adapted to receive from the third environmental microphone 5-3 a third occupant signal S3_oc carrying a third acoustic signal of the acquired voice of the first and/or second and/or third occupant(s) and possibly carrying one or more echoes caused by the acoustic signal emitted by the loudspeakers 3-1, 3-2, 12-1, 12-2, 22-1, 22-1 of the first, second and third local units 1, 10, 20.
• the processing unit 50 further comprises a fourth input terminal adapted to receive from the first local unit 1 a first input reference signal S1_ref_in carrying a first return signal representative of the voice of the remote user 30 who is speaking with the first occupant or representative of audio data of a music track or a voice signal of a response of a voice assistant; the processing unit 50 is then configured to transmit towards the user interface unit 40 an internal output interface signal S_IDC_o_int carrying the voice of the first occupant who is speaking with the remote user 30, finally the user interface unit 40 is configured to receive the internal output interface signal S_IDC_o_int and transmit towards the remote user 30 an output interface signal S_IDC_o carrying the voice of the first and/or second and/or third occupant(s) who is/are speaking with the remote user 30.
• a fourth input terminal adapted to receive from the first local unit 1 a first input reference signal S1_ref_in carrying a first return signal representative of the voice of the remote user 30 who is speaking with the first occupant or representative of
• the processing unit 50 further comprises a fifth input terminal adapted to receive from the second local unit 10 a second input reference signal S2_ref_in carrying a second return signal representative of the voice of the remote user 30 who is speaking with the second occupant or representative of audio data of a music track or a voice signal of a response of a voice assistant; the processing unit 50 is then configured to transmit towards the user interface 40 the internal output interface signal S_IDC_o_int carrying the voice of the first and/or second and/or third occupant(s) who is/are speaking with the remote user 30, finally the user interface unit 40 is configured to receive the internal output interface signal S_IDC_o_int and transmit towards the remote user 30 the output interface signal S_IDC_o carrying the voice of the first and/or second and/or third occupant(s) who is/are speaking with the remote user 30.
• the processing unit 50 further comprises a sixth input terminal adapted to receive from the third local unit 20 a third input reference signal S3_ref_in carrying a third return signal representative of the voice of the remote user 30 who is speaking with the third occupant or representative of audio data of a music track or a voice signal of a response of a voice assistant; the processing unit 50 is then configured to transmit towards the user interface unit 40 the internal output interface signal S_IDC_o_int carrying the voice of the first and/or second and/or third occupant(s) who is/are speaking with the remote user 30, finally the user interface unit 40 is configured to receive the internal output interface signal S_IDC_o_int and transmit towards the remote user 30 the output interface signal S_IDC_o carrying the voice of the first and/or second and/or third occupant(s) who is/are speaking with the remote user 30.
• the first local unit 1 when the first occupant is performing a voice call with the remote user 30, the first local unit 1 is configured to receive the first output reference signal S1_ref_o carrying the voice of the remote user 30 who is speaking, then the first local unit 1 is configured to process said received signal of the voice of the remote user 30 so that the acoustic field generated by the first and second loudspeakers 3-1, 3-2 (representative of the voice 30 of the remote user who is speaking) is appropriately directed towards the ears of the first occupant positioned in proximity to the first local unit 1, while the acoustic field of the first and second loudspeakers 3-1, 3-2 is attenuated in the other directions, in particular it is attenuated towards the second and third occupants positioned in proximity to the second and third local units 10, 20: in this way the voice of the remote user 30 is not perceived (or is very attenuated) by the second and third occupants who are participating in the voice call with the remote user 30, as will be explained in more detail below.
• the second local unit 10 when the second occupant is performing a voice call with the remote user 30, the second local unit 10 is configured to receive the second output reference signal S2_ref_o carrying the voice of the remote user 30 who is speaking, then the second local unit 10 is configured to process said received signal of the voice of the remote user 30 so that the acoustic field generated by the third and fourth loudspeakers 12-1, 12-2 is appropriately directed towards the ears of the second occupant positioned in proximity to the second local unit 10, while the acoustic field of the third and fourth loudspeakers 12-1, 12-2 is attenuated in the other directions, in particular it is attenuated towards the first and third occupants positioned in proximity to the first and third local units 1, 20; finally when the third occupant is performing a voice call with the remote user 30, the third local unit 20 is configured to receive the third output reference signal S3_ref_or carrying the voice of the remote user 30 who is speaking, then the third local unit 20 is configured to process said received signal of the voice of the remote user 30 so that the
• the closed environment is for example the passenger compartment of a motor vehicle, in particular a three-seater motor vehicle provided with three seats and three respective headrests: in this case the first local unit 1 is a first headrest unit 1 which is associated with the first headrest fixed to a first seat of a driver of the motor vehicle seated in the first seat, the second local unit is a second headrest unit which is associated with the second headrest fixed to a second seat of a first passenger seated in the second seat, and the third local unit is a third headrest unit which is associated with the third headrest fixed to a third seat of a second passenger seated in the third seat.
• the first local unit 1 is a first headrest unit 1 which is associated with the first headrest fixed to a first seat of a driver of the motor vehicle seated in the first seat
• the second local unit is a second headrest unit which is associated with the second headrest fixed to a second seat of a first passenger seated in the second seat
• the third local unit is a third headrest unit which is associated
• the three environmental microphones 5-1, 5-2, 5-3 are positioned within the passenger compartment, for example according to the following alternative configurations:
• the loudspeakers 3-1, 3-2 of the first headrest unit 1, the loudspeakers 12-1, 12-2 of the second headrest unit 10 and the loudspeakers 22-1, 22-2 of the third headrest unit 20 are positioned on a front side of the respective headrest as shown in Figure 4 , wherein the front side means the side facing the head of the occupant.
• processing unit 50 is shown in more detail.
• the processing unit 50 further comprises the first, second and third output terminals adapted to transmit, respectively, the first output reference signal S1_ref_o, the second output reference signal S2_ref_o and the third output reference signal S3_ref_o, as illustrated above.
• the processing unit 50 further comprises the fourth, fifth and sixth input terminals adapted to receive, respectively, the first input reference signal S1_ref_in, the second input reference signal S2_ref_in and the third input reference signal S3_ref_in, as illustrated above.
• the processing unit 50 comprises a cascade connection of an acoustic echo canceller 55, a source separator 56, a post-filtering and noise cancellation sub-unit 57, a router 58 and a selector 59.
• the processing unit 50 is realized for example in hardware, by means of suitable digital electronic circuits; in particular, the processing unit can be realized with an application-specific integrated circuit (ASIC), a programmable electronic circuit (FPGA) or a digital signal processor (DSP).
• ASIC application-specific integrated circuit
• FPGA programmable electronic circuit
• DSP digital signal processor
• the acoustic echo canceller 55 has the function of processing the voice signals acquired by the environmental microphones 5-1, 5-2, 5-3 and the first and/or second and/or third return signal(s) of the voice of the remote user 30 who is speaking or the return signal of a music track or the return signal of a response of a voice assistant, so as to extract the voice signal of the first and/or second and/or third occupant(s) who is/are speaking with the remote user 30, attenuating (at the limit cancelling) one or more echoes of the voice of the remote user 30 and/or the echo of a music track and/or the echo of a response of a voice assistant.
• the acoustic echo canceller 55 comprises a first group of three inputs adapted to receive respectively the signals generated by the three environmental microphones 5-1, 5-2, 5-3, comprises a second group of three further inputs adapted to receive the three input reference signals S1_ref_in, S2_ref_in, S3_ref_in transmitted respectively by the three local units 1, 10, 20, and comprises three outputs adapted to transmit three respective signals S1_aec, S2_aec, S3_aec towards the source separator 56.
• the number of inputs of the first group is equal to the number of the environmental microphones present within the closed environment
• the number of inputs of the second group and the number of outputs is equal to the number of the local units present in the system 100.
• the acoustic echo canceller 55 is configured to receive from the first environmental microphone 5-1 the first occupant signal S1_oc carrying the first voice signal of the voice of the first occupant who is speaking with the remote user 30 or with another occupant (and therefore the acoustic echo canceller 55 considers as an interfering noise the voice signal of the second and third occupant acquired by the first environmental microphone 5-1) and possibly one or more acoustic echoes caused by the acoustic signals emitted by the loudspeakers 3-1, 3-2, 12-1, 12-2, 22-1, 22-2 (for example, the echo of the remote user 30 who is speaking caused by the loudspeakers 3-1, 3-2 emitting the acoustic signal of the voice of the remote user 30 and which is acquired by the first environmental microphone 5-1), is configured to receive from the second environmental microphone 5-2 the second occupant signal S2_oc carrying the second voice signal of the voice of the second occupant who is speaking with the remote user 30 or with another occupant (and then the acous
• the source separator 56 has the function of isolating the voice signals of the individual occupants who are speaking with the remote user (or with another occupant or with a voice assistant) by means of a processing the signals S1_aec, S2_aec, S3_aec received by the acoustic echo canceller 55, generating as output, as a function of the three signals S1_aec, S2_aec, S3_aec, three respective separate signals S1_s, S2_s, S3_s carrying three respective voice signals of the corresponding occupant who is speaking with the remote user 30 (or with another occupant or is interacting with a voice assistant).
• the source separator 56 is configured to generate on the first output terminal the first separate signal S1_s carrying the first voice signal of the occupant (and possibly the environmental noise), while the second and third voice signals of the occupants are considered interfering noise and are therefore greatly attenuated (or even eliminated).
• the source separator 56 is configured to generate on the second output terminal the second separate signal S2_s carrying the second voice signal of the occupant (and possibly environmental noise), while the first and third voice signals of the occupants are considered interfering noise and are therefore greatly attenuated (or even eliminated).
• the post-filtering and noise cancellation sub-unit 57 has the function of reducing (at the limit of cancelling) at least a part of the environmental noise present within the closed environment (in particular, the rolling noise of the tires of a motor vehicle, the noise of the wind, the noise of the engine of the vehicle and the noise caused by unevenness of the road travelled by the motor vehicle), in order to reduce the environmental noise perceived by the remote user 30 by means of a processing in the digital domain, generating as output three respective filtered signals S1_ft, S2_ft, S3_ft.
• the post-filtering and noise cancellation sub-unit 57 is configured to perform a post-filtering of the three separate signals S1_s, S2_s, S3_s and a subsequent reduction (at the limit, cancellation) of the environmental noise, generating as output the three respective filtered signals S1_ft, S2_ft, S3_ft carrying three respective voice signals of the corresponding occupant who is speaking with the remote user 30.
• the router 58 has the function of routing the voice signal of the remote user 30 towards the first and/or second and/or third local unit(s) 1, 10, 20, as a function of the value of a selection signal S_sel indicative of the selection of the first and/or second and/or third occupant(s), as will be explained in more detail below.
• the router 58 has the function of routing the voice signal of an occupant who is speaking towards one of the first, second, third local units 1, 10, 20 different from that associated with the occupant who is speaking, in order to allow an internal voice communication between the two occupants within the closed environment.
• the first local unit 1 is shown in more detail.
• the first local unit 1 comprises the first and second microphones 2-1, 2-2, the first and second loudspeakers 3-1, 3-2, an audio pre-processor 1.2, an audio active noise attenuator 1.1 and an audio post-processor 1.4.
• the first local unit 1 is realized, for example, with a printed circuit board on which the indicated components are fixed or connected, wherein the printed circuit board is integrated (in the case where the closed environment is the passenger compartment of a motor vehicle) within the headrest 200 shown in Figure 4 ; alternatively, the first local unit 1 is realized with a single hardware component, such as a digital signal processor (DSP), a programmable electronic component (FPGA) or an application-specific integrated circuit (ASIC).
• DSP digital signal processor
• FPGA programmable electronic component
• ASIC application-specific integrated circuit
• the first local unit 1 can also be realized with an earpiece provided with two loudspeakers and with one or more microphones, wherein the two loudspeakers are positioned in proximity to the two respective ears of the first occupant.
• the audio pre-processor 1.2 has the function of appropriately directing the acoustic signal of the voice of the remote user 30 (who is speaking with the first occupant) or the audio of a music track, so that the first and second loudspeakers 3-1, 3-2 emit an acoustic signal of the voice of the remote user 30 or of the audio of the music track or a response of a voice assistant that is appropriately directed towards the ears of the first driver, and so that the emitted acoustic signal of the voice of the remote user 30 who is speaking or of the audio of the music track or the response of the voice assistant is attenuated in the other directions of the closed environment, in particular the acoustic signal of the voice of the remote user 30 or of the audio of the music track or the response of the voice assistant is attenuated towards the second and third occupants.
• the audio pre-processor 1.2 is electrically connected as input with the processing unit 50 and is electrically connected as output with the audio post-processor 1.4; the audio pre-processor 1.2 is configured to receive as input the first output reference signal S1_ref_o carrying the voice of the remote user 30 (who is speaking with the first occupant), and is configured to generate, as a function thereof, a first directional signal S1_dir and a second directional signal S2_dir carrying the voice of the remote user 30, so that the acoustic field of the voice of the remote user 30 emitted by the first and second loudspeakers 3-1, 3-2 is appropriately directed towards the first occupant positioned in the station of the first local unit 1, while the acoustic field of the voice of the remote user 30 emitted by the first and second loudspeakers 3-1, 3-2 is attenuated in the other directions, in particular it is attenuated towards the second and third occupants that are positioned in the stations respectively of the second and third local units 10, 20.
• the directionality of the generated acoustic field of the voice of the remote user 30 is obtained by means of generation of the first and second directional signals S1_dir, S2_dir by filtering the first output reference signal S1_ref_o and possibly as a function of the first tracking signal S_tr, so that the phase and amplitude difference values between the first and second directional signals S1_dir, S2_dir control the direction in the space of the acoustic field of the voice of the remote user 30 emitted by the first and second loudspeakers 3-1, 3-2, thus allowing the voice of the remote user 30 to be directed towards the first occupant.
• the first and second directional signals S1_dir, S2_dir have the same amplitude and an appropriate phase difference: the value of said phase difference controls the direction in the space of the acoustic field of the voice of the remote user 30 emitted by the first and second loudspeakers 3-1, 3-2.
• the audio active noise attenuator 1.1 has the function of reducing (at the limit eliminating, i.e. masking) the interfering noise generated by the second and third occupant in proximity to the ears of the first occupant when the remote user 30 is speaking with the first occupant and has the further function of reducing (at the limit eliminating) at least a part of the environmental noise in proximity to the ears of the first occupant within the closed environment (in particular, the rolling noise of the tyres of a motor vehicle, the noise of the wind, the noise of the engine of the vehicle and the noise caused by unevenness of the road travelled by the motor vehicle), in order to reduce (at the limit eliminate) the interfering noise and at least part of the environmental noise perceived by the ears of the first occupant who is speaking by means of a processing in the acoustic domain.
• the audio active noise attenuator 1.1 is electrically connected as input with the first microphone 2-1, with the second microphone 2-2 and with the processing unit 50, and is electrically connected as output with the post-processor 1.4; the audio active noise attenuator 1.1 is configured to receive as input, by means of the first and second microphones 2-1, 2-2, the interfering noise of the voice of the second and third occupants and/or the environmental noise present within the closed environment, is configured to receive the first output reference signal S1_ref_o carrying the voice of the remote user 30 who is speaking, is configured to perform an audio processing of the interfering noise of the voice of the second and third occupants and/or of the environmental noise and of the voice of the remote user, and is configured to generate as output, as a function of said processing, a first anti-noise signal S1_anc and a second anti-noise signal S2_anc allowing to attenuate (at the limit cancel) the interfering noise of the voice of the second and third
• the post-processor 1.4 has the function of combining the voice signal of the remote user 30 with the first and second anti-noise signals S1_anc, S2_anc, generating from these the first and second driving signals S1.1_spk, S1.2_spk for driving the first and second loudspeakers 3-1, 3-2, respectively.
• the post-processor 1.4 is electrically connected as input with the pre-processor 1.2 and with the audio active noise attenuator 1.1, and is electrically connected as output with the first and second loudspeakers 3-1, 3-2.
• the post-processor 1.4 is realized with a first and a second adder, wherein:
• the electronic system 100 further comprises a first pair of position sensors 4-1, 4-2, a second pair of position sensors 14-1, 14-2 and a third pair of position sensors 24-1, 24-2; furthermore the first local unit 1 further comprises a first ear position tracking sub-unit 1.3 electrically connected to the first pair of position sensors 4-1, 4-2, the second local unit 10 comprises a position tracking sub-unit electrically connected to the first pair of position sensors 14-1, 14-2 and the third local unit 20 comprises a position tracking sub-unit electrically connected to the third pair of position sensors 24-1, 24-2.
• the first ear position tracking sub-unit 1.3 (i.e. an ear position tracker) has the function of estimating, as the time varies, the position in the space of the ears of the first occupant who is in a first fixed position within the closed environment: this allows the audio pre-processor 1.2 to appropriately direct the acoustic field of the voice of the remote user 30 (who is speaking with the first occupant) towards the ears of the first occupant and allows to attenuate the acoustic field of the voice of the remote user 30 towards the second and third occupants (who are not speaking with the remote user 30).
• the first ear position tracking sub-unit 1.3 is electrically connected as input with the first and second position sensors 4-1, 4-2 and is electrically connected as output with the active noise attenuator 1.1 and with the audio pre-processor 1.2.
• the first and second position sensors 4-1, 4-2 each have the function of acquiring a two-dimensional representation of a respective portion of the head of the first occupant visible to each of the first and second position sensors 4-1, 4-2, generating respectively a first and a second position signals S1.1_p, S1.2_p representative of the respective two-dimensional representation of the portion of the head of the first occupant.
• Said two-dimensional representation of the portion of the head of the first occupant may be a colour image acquired by means of the first or second position sensor 4-1, 4-2 which are a respective camera, or may be a black and white image acquired by means of the first or second position sensor 4-1, 4-2 which are a respective infrared camera, or may be a depth map generated by means of the first or second position sensor 4-1, 4-2 which are time-of-flight sensors.
• the first ear position tracking sub-unit 1.3 is configured to receive from the position sensor 4-1 and 4-2 respectively the first and second position signals S1.1_p, S1.2_p carrying the respective two-dimensional representation of the portion of the head of the first occupant and is configured to generate, as a function of them, a first tracking signal S_tr representative of the time-variant estimation of the position in the space of the ears of the first occupant.
• the audio pre-processor 1.2 is further configured to receive as input the first tracking signal S_tr and is configured to generate, as a function of the first output reference signal S1_ref_o carrying the voice of the remote user 30 and as a function of the tracking signal S_tr, the first directional signal S1_dir and the second directional signal S2_dir carrying the voice of the remote user 30, so that the acoustic field of the voice of the remote user 30 emitted by the first and second loudspeakers 3-1, 3-2 is suitably directed towards the first occupant positioned at the station of the first local unit 1, while the acoustic field of the voice of the remote user 30 emitted by the first and second loudspeakers 3-1, 3-2 is attenuated in the other directions, in particular it is attenuated towards the second and third occupants which are positioned at the stations of the second and third local units 10, 20, respectively.
• the audio active noise attenuator 1.1 is further configured to receive as input the first tracking signal S_tr and is configured to generate, as a function of the interfering noise of the voice of the second and third occupants and/or of the environmental noise present within the closed environment, as a function of the first output reference signal S1_ref_o carrying the voice of the remote user 30 who is speaking and as a function of the tracking signal S_tr, the first anti-noise signal S1_anc and the second anti-noise signal S2_anc.
• the presence of the first ear position tracking sub-unit 1.3 is not essential for the purposes of the realization of the invention: in this case the position of the ears is estimated by generalizing with the position of a generic occupant having the head turned frontally (for example, turned towards the direction of travel in the case of a driver of a motor vehicle).
• the presence of the audio active noise attenuator 1.1 and of the first and second microphones 2-1, 2-2 is not essential for the purposes of the realization of the invention: in this case the remote user 30 (who is speaking with the first occupant) receives the voice of the first occupant which is not disturbed by the interfering noise and by the environmental noise present within the closed environment, but in this case the first occupant also perceives the interfering noise (for example generated by the second and/or third occupant(s)) and the environmental noise present within the closed environment.
• the above considerations relating to the first local unit 1 provided with the first head position tracking sub-unit 1.3 are applicable in a similar way to the second and third local units 10 and 20, by replacing the first occupant respectively with the second and third occupants.
• the second local unit 10 comprises a second head position tracking sub-unit (not shown in the figures) having the function of estimating, as the time varies, the position in the space of the ears of the second occupant who is in a second fixed position within the closed environment; in particular, the second head position tracking sub-unit is configured to receive the third and fourth position signals S2.1_p, S2.2_p and generate, as a function of them, a second tracking signal representative of the time-variant estimation of the position in the space of the ears of the second occupant.
• the second head position tracking sub-unit is configured to receive the third and fourth position signals S2.1_p, S2.2_p and generate, as a function of them, a second tracking signal representative of the time-variant estimation of the position in the space of the ears of the second occupant.
• the third local unit 20 comprises a third head position tracking sub-unit (not shown in the figures) having the function of estimating, as the time varies, the position in the space of the ears of the third occupant who is in a third fixed position within the closed environment; in particular, the third head position tracking sub-unit is configured to receive the fifth and sixth position signals S3.1_p, S3.2_p and generate, as a function of them, a third tracking signal representative of the time-variant estimation of the position in the space of the ears of the third occupant.
• a headrest 200 fixed above a seat of a motor vehicle wherein the seat is for example the seat of the driver of the motor vehicle or the seat of a passenger.
• the headrest 200 comprises the first headrest unit 1, in which three microphones 2-1, 2-2, 2-3, three loudspeakers 3-1, 3-2, 3-2 and two position sensors 4-1, 4-2 are visible.
• the three loudspeakers 3-1, 3-2, 3-2 and the two position sensors 4-1, 4-2 are positioned in a front portion of the headrest 200, i.e., they are positioned in a portion of the headrest 200 that is turned towards the head of the driver or passenger.
• the three microphones 2-1, 2-2, 2-3 are positioned in a rear portion of the headrest 200, i.e. they are positioned in a portion of the headrest 200 that is opposite the head of the driver or passenger.
• the closed environment is the passenger compartment of a motor vehicle provided with three seats with respective headrests, wherein a driver is sitting in a first seat having a headrest in which the first headrest unit 1 is mounted, while the first passenger is sitting in a second seat having a headrest in which the second headrest unit 10 is mounted and the second passenger is sitting in a third seat having a headrest in which the third headrest unit 20 is mounted.
• a voice call is performed through a mobile radio network between the driver of the vehicle and the remote user 30 provided with a smartphone, while the first and second passengers are speaking with each other (so they are not speaking with the remote user 30).
• head tracking sub-units are not present within the first, second and third headrest units 1, 10, 20.
• the driver begins to speak with the remote user 30 and thus the first environmental microphone 5-1 acquires the voice of the driver who is speaking; moreover the first environmental microphone 5-1 also acquires an interfering noise of the voice of the first and second passengers who are speaking with each other and also acquires an environmental noise present within the passenger compartment, in which the intensity of the interfering noise of the acquired voice of the first and second passengers is different from that of the voice of the driver.
• the second and third environmental microphone 5-2, 5-3 also acquire the voice of the driver, which is considered an interfering noise, acquire the interfering noise of the voice of the first and second passengers who are speaking with each other and also acquire the environmental noise within the passenger compartment, in which the intensity of the acquired voice of the driver is different from that of the interfering noise of the voice of the first and second passengers.
• the microphones 2-1, 2-2 of the first headrest unit 1 acquire the interfering noise of the voice of the driver who is speaking with the remote user 30, acquire the environmental noise and possibly acquire the interfering noise of the voice of the first and second passengers who are speaking with each other.
• the microphones 13-1, 13-2 of the second headrest unit 10 acquire the interfering noise of the voice of the first passenger who is speaking with the second passenger, acquire the environmental noise present within the passenger compartment and possibly acquire the interfering noise of the voice of the driver and of the second passenger.
• the microphones 23-1, 23-2 of the third headrest unit 20 acquire the interfering noise of the voice of the second passenger who is speaking with the first passenger, acquire the environmental noise and possibly acquire the interfering noise of the voice of the driver and of the first passenger.
• the router 58 of the processing unit 50 receives the selection signal S_sel indicative of the selection of the voice of the driver.
• the voice signal of the remote user 30 is received by the user interface unit 40 by means of the input interface signal S_IDC_in, which is forwarded as output on the internal input interface signal S_IDC_in_int, which is in turn received by the processing unit 50 and is routed, by means of the router 58 and of the value of the selection signal S_sel, towards the first headrest unit 1 of the driver by means of the first output reference signal S1_ref_o generated by the first output terminal of the router 58.
• the first headrest unit 1 receives the first output reference signal S1_ref_o carrying the voice signal of the remote user 30 who is speaking, then the first audio pre-processor 1.2 receives as input the first output reference signal S1_ref_o of the voice of the remote user 30 and performs an audio type pre-processing; in particular, the first audio pre-processor 1.2 generates as output the first directional signal S1_dir and the second directional signal S2_dir, so that the acoustic field of the voice of the remote user 30 emitted by the first and second loudspeakers 3-1, 3-2 is appropriately directed towards the driver seated on the first driving seat and having the head positioned in proximity to the headrest provided with the first headrest unit 1, while the acoustic field of the voice of the remote user 30 emitted by the first and second loudspeakers 3-1, 3-2 is attenuated in the other directions, in particular it is attenuated towards the first and second passengers who are seated in the
• the audio active noise attenuator 1.1 receives as input the first output reference signal S1_ref_o carrying the voice of the remote user 30 who is speaking with the driver, receives as input (from the microphones 2-1, 2-2) the interfering noise of the voice of the driver and of the first and second passengers who are speaking with each other, the environmental noise within the passenger compartment: the audio active noise attenuator 1.1 then attenuates the interfering noise of the voice of the driver and of the first and second passengers and also attenuates at least in part the environmental noise in proximity to the ears of the driver, by using the voice signal of the remote user 30, in which said attenuation is performed by means of generating as output the first and second anti-noise signals S1_anc, S2_anc carrying the signal in counter-phase of the interfering noise of the voice of the driver and of the voice of the first and second passengers and of at least part of the environmental noise.
• the post-processor 1.4 receives as input the first directional signal S1_dir carrying the directed voice of the remote user 30, receives as input the first anti-noise signal S1_anc carrying the signal in counter-phase of the interfering noise of the voice of the driver and of the first and second passengers and at least part of the environmental noise, then the post-processor 1.4 generates as output the first driving signal S1.1_spk driving the first loudspeaker 3-1 generating an acoustic signal of the voice of the remote user 30 who is speaking, so that the acoustic field of the voice of the remote user 30 emitted by the first loudspeaker 3-1 is directed mainly towards the ears of the driver.
• the post-processor 1.4 receives as input the second directional signal S2_dir carrying the directed voice of the remote user 30, receives as input the second anti-noise signal S2_anc carrying the signal in counter-phase of the interfering noise and of at least part of the environmental noise, then the post-processor 1.4 generates as output the second driving signal S1.2_spk driving the second loudspeaker 3-2 generating an acoustic signal of the voice of the remote user 30 who is speaking, so that the acoustic field of the voice of the remote user 30 emitted by the second loudspeaker 3-2 is directed mainly towards the ears of the driver.
• the post-processor 1.4 generates as output the first input reference signal S1_ref_in carrying a first return signal of the voice of the remote user 30 who is speaking with the driver.
• the driver of the vehicle listens to the voice of the remote user 30 (who is speaking) by means of the first and second loudspeakers 3-1, 3-2, without being disturbed by the voices of the second and third passengers who are speaking and without being disturbed by the environmental noise, by means of the audio active noise attenuator 1.1 and by means of the pre-processor 1.2.
• the environmental microphone 5-1 of the driver acquires at least part of said acoustic signals of the voice of the remote user 30, thus acquiring an echo of the voice of the remote user 30.
• the environmental microphones 5-2, 5-3 of the first and second passengers also acquire at least part of the acoustic signals of the voice of the remote user 30 emitted by the first and second loudspeakers 3-1, 3-2, thus generating a further echo of the voice of the remote user 30, wherein the intensity of the further echo is typically less than that of the echo detected at the environmental microphone 5-1 of the driver.
• the acoustic echo canceller 55 receives from the first environmental microphone 5-1 the first occupant signal S1_oc carrying the voice of the driver who is speaking with the remote user 30, carries the interfering noise of the voice of the first and second passengers who are speaking with each other, carries at least part of the environmental noise and carries the echo of the remote user 30, receives from the second environmental microphone 5-2 the second occupant signal S2_oc carrying the interfering noise of the voice of the driver who is speaking with the remote user 30 and of the voice of the first and second passengers who are speaking with each other, carries at least part of the environmental noise and carries the echo of the remote user 30, receives from the third environmental microphone 5-3 the third occupant signal S3_oc carrying the voice of the driver who is speaking with the remote user 30, carries the interfering noise of the voice of the driver who is speaking with the remote user 30 and of the voice of the first and second passengers who are speaking with each other, carries at least part of the environmental noise and
• the post-filtering and noise cancellation sub-unit 57 receives on the first input terminal the voice signal of the driver and at least part of the environmental noise, receives on the second and third input terminal at least part of the environmental noise, then performs a post-filtering of the voice signal of the driver and a reduction (at the limit, cancellation) of said at least part of the environmental noise, thus generating on the first output terminal the first filtered signal S1_ft carrying the voice of the driver who is speaking with the remote user 30.
• the selector 59 receives the selection signal S_sel indicative of the selection of the voice of the driver, receives as input the first, second and third filtered signal S1_ft, S2_ft, S3_ft and transmits on the output terminal the internal output interface signal S_IDC_o_int equal to the first filtered signal S1_ft carrying the voice of the driver who is speaking with the remote user 30.
• the interface unit 40 receives as input the internal output interface signal S_IDC_o_int and generates as output the output interface signal S_IDC_o carrying the voice of the driver who is speaking with the remote user 30.
• the remote user 30 receives the voice of the driver, by means of a mobile radio network: in this way the remote user 30 listens to the voice of the driver of the vehicle who is speaking with a good quality, since the voice of the driver received by the remote user 30 is not disturbed by the voice of the first and second passengers nor by the environmental noise within the vehicle.
• the remote user 30 is speaking both with the driver and with the first passenger.
• the operation differs from the first operation in that the router 58 of the processing unit is further configured to route the voice of the remote user 30 towards the second headrest unit 10, therefore the above considerations relating to the first headrest unit 1 are similarly applicable to the second headrest unit 10, with the difference that the first environmental microphone 5-1 acquires a further echo of the voice of the remote user 30 caused by the loudspeakers 12-1, 12-2 of the second headrest unit 10, which emit the voice of the remote user 30 that is heard by the first passenger.
• the first passenger is listening to a music track, which is reproduced by means of the loudspeakers 12-1, 12-2 of the second headrest unit 10.
• the operation of the first variant differs from the first operation in that the router 58 of the processing unit 50 further transmits (at instant t1) to the second headrest unit 10 the output reference signal S2_ref_o carrying the audio of the music track, then the second headrest unit 10 receives the audio of the music track and drives the loudspeakers 12-1, 12-2 emitting the acoustic signal of the audio of the music track, which is then heard by the first passenger.
• the operation of the second headrest unit 10 is similar to that of the first headrest unit 1, with the difference that the audio of the music track is processed and the acoustic field of the audio of the music track generated by the loudspeakers 12-1, 12-2 is appropriately directed towards the ears of the first passenger, who then listens to the audio of the music track with a good quality, i.e. without being disturbed by the voice of the driver who is speaking with the remote user 30 and, vice versa, the driver listens to the voice of the remote user 30 without being disturbed by the audio of the music track.
• the acoustic echo canceller 55 receives from the first, second and third environmental microphones respectively the first, second and third occupant signals S1_oc, S2_oc, S3_oc further carrying the further echoes of the audio of the music track, then the acoustic echo canceller 55 also performs a reduction of said further echoes of the audio of the music track: in this way the remote user 30 listens to the voice of the driver of the vehicle who is speaking with a good quality, without being disturbed by the audio of the music track.
• a second operation of the electronic system 100 will be described below, wherein the electronic system 100 differs from that of the first operation in that the first headrest unit 1 of the driver further comprises the first ear position tracking sub-unit 1.3.
• the second operation differs from the first operation in that at instant t1 the first ear position tracking sub-unit 1.3 receives, from the first and second position sensors 4-1, 4-2, the first and second position signals S1.1_p, S1.2_p carrying a respective two-dimensional representation of a portion of the head of the driver and generates, as a function of them, the first tracking signal S_tr representative of the time-variant estimation of the position in the space of the ears of the driver.
• the first audio pre-processor 1.2 generates the first directional signal S1_dir and the second directional signal S2_dir, further taking into account the first tracking signal S_tr representative of the estimation of the position in the space of the ears of the driver; in addition, the audio active noise attenuator 1.1 generates as output the first and second anti-noise signals S1_anc, S2_anc carrying the signal in counter-phase of the interfering noise and of the environmental noise, further taking into consideration the first tracking signal S_tr representative of the estimation of the position in the space of the ears of the driver.
• a third operation of the electronic system 100 will be described below, wherein the electronic system 100 differs from that of the first operation in that both the driver of the vehicle and a first passenger are speaking with the remote user 30, while a second passenger is speaking alone (or is singing a song, or is listening to a song reproduced by a smartphone loudspeaker), thus generating an acoustic signal that will be considered an interfering noise.
• the third operation differs from the first operation in that the first environmental microphone 5-1 acquires the voice of the driver who is speaking with the remote user 30 and acquires also the voice of the first passenger which is considered an interfering noise with respect to the voice of the driver; moreover the first environmental microphone 5-1 acquires the interfering noise of the second passenger who is speaking by him-/herself (for example, he/she is singing a song or listening to a song reproduced by a loudspeaker of a smartphone of the second passenger) and also acquires the environmental noise within the passenger compartment.
• the first environmental microphone 5-1 acquires the voice of the driver who is speaking with the remote user 30 and acquires also the voice of the first passenger which is considered an interfering noise with respect to the voice of the driver; moreover the first environmental microphone 5-1 acquires the interfering noise of the second passenger who is speaking by him-/herself (for example, he/she is singing a song or listening to a song reproduced by a loudspeaker of a smartphone of the second passenger) and
• the second environmental microphone 5-2 acquires the voice of the first passenger who is speaking with the remote user 30 and acquires also the voice of the driver which is considered an interfering noise with respect to the voice of the first passenger; in addition the second environmental microphone 5-2 acquires the interfering noise of the voice of the second passenger and also acquires the environmental noise within the passenger compartment.
• the third environmental microphone 5-3 acquires the interfering noise of the voice of the driver, of the first and of the second passenger and also acquires the environmental noise within the passenger compartment.
• the microphones 2-1, 2-2 of the first headrest unit 1 acquire the interfering noise of the voice of the driver, the environmental noise and possibly the interfering noise of the voice of the first and second passengers
• the microphones 13-1, 13-2 of the second headrest unit 10 acquire the interfering noise of the voice of the first passenger, the environmental noise and possibly the interfering noise of the voice of the driver and of the second passenger
• the microphones 23-1, 23-2 of the third headrest unit 20 acquire the interfering noise of the voice of the second passenger, the environmental noise and possibly the interfering noise of the voice of the driver and of the first passenger.
• the router 58 of the processing unit 50 receives the selection signal S_sel indicative of the selection of the voice of the driver and of the first passenger.
• the voice signal of the remote user 30 is received by the user interface unit 40 by means of the input interface signal S_IDC_in, which is forwarded as output on the internal input interface signal S_IDC_in_int, which is in turn received by the processing unit 50 and is routed, by means of the router 58 and by the value of the selection signal S_sel:
• the second headrest unit 1 receives the second output reference signal S2_ref_o carrying the voice signal of the remote user 30 who is speaking also with the first passenger, then the second audio pre-processor (similar to the first audio processor 1.2) receives as input the second output reference signal S2_ref_o of the voice of the remote user 30 and performs an audio type pre-processing; in particular, the second audio pre-processor generates as output a third directional signal (similar to the first directional signal S1_dir) and a fourth directional signal (similar to the second directional signal S2_dir), so that the acoustic field of the voice of the remote user 30 emitted by the third and fourth loudspeakers 12-1, 12-2 is appropriately directed towards the first passenger seated on the first passenger seat and having the head positioned in proximity to the headrest provided with the second headrest unit 10, while the acoustic field of the voice of the remote user 30 emitted by the third and fourth loudspeakers 12-1, 12-2 is
• a second audio active noise attenuator (similar to the audio active noise attenuator 1.1) receives as input the second output reference signal S2_ref_o carrying the voice of the remote user 30 who is speaking with the first passenger, receives as input (from the microphones 13-1, 13-2) the interfering noise of the voice of the driver and of the first and second passengers and the environmental noise within the passenger compartment: the second audio active noise attenuator then attenuates the interfering noise of the voice of the second passenger and of the driver and of the first passenger and also attenuates at least in part the environmental noise in proximity to the ears of the first passenger, by using the signal of the voice of the remote user 30, in which said attenuation is performed by generating as output a third and a fourth anti-noise signals (similar to the first and second anti-noise signals S1_anc, S2_anc) carrying the signal in counter-phase of the interfering noise of the voice of the second passenger, of the voice of the driver and
• a second post-processor receives as input the third directional signal carrying the directed voice of the remote user 30, receives as input the third anti-noise signal carrying the signal in counter-phase of the interfering noise of the voice of the second passenger, of the voice of the driver and of the first passenger and of at least part of the environmental noise, then the second post-processor generates as output the third driving signal S2.1_spk driving the third loudspeaker 12-1 generating an acoustic signal of the voice of the remote user 30 who is speaking, so that the acoustic field of the voice of the remote user 30 emitted by the third loudspeaker 12-1 is directed mainly towards the ears of the first passenger.
• the second post-processor receives as input the fourth directional signal carrying the directed voice of the remote user 30, receives as input the fourth anti-noise signal carrying the signal in counter-phase of the interfering noise of the voice of the second passenger, of the voice of the driver and of the first passenger and of at least part of the environmental noise, then the second post-processor generates as output the fourth driving signal S2.2_spk driving the fourth loudspeaker 12-2 generating an acoustic signal of the voice of the remote user 30 who is speaking, so that the acoustic field of the voice of the remote user 30 emitted by the fourth loudspeaker 12-2 is directed mainly towards the ears of the first passenger.
• a second post-processor (similar to post-processor 1.4) generates as output the second input reference signal S2_ref_in carrying a second return signal of the voice of the remote user 30 who is speaking also with the first passenger.
• the first passenger of the vehicle listens to the voice of the remote user 30 (who is speaking) by means of the third and fourth loudspeakers 12-1, 12-2, without being disturbed by the voices of the third passenger and without being disturbed by the environmental noise, by means of the second audio active noise attenuator and by means of the second pre-processor.
• the second environmental microphone 5-2 acquires a third echo of the voice of the remote user 30 (caused by the first and second loudspeakers 3-1, 3-2) and a fourth echo of the voice of the remote user (caused by the third and fourth loudspeakers 12-1, 12-2); finally, the third environmental microphone 5-3 acquires a fifth echo of the voice of the remote user 30 (caused by the first and second loudspeakers 3-1, 3-2) and a sixth echo of the voice of the remote user (caused by the third and fourth loudspeakers 12-1, 12-2).
• the acoustic echo canceller 55 receives from the first environmental microphone 5-1 the first occupant signal S1_oc carrying the voice of the driver who is speaking with the remote user 30, carries the interfering noise of the voice of the first and second passengers, carries at least part of the environmental noise and carries the first and second echoes of the remote user 30.
• the acoustic echo canceller 55 receives from the second environmental microphone 5-2 the second occupant signal S2_oc carrying the voice of the first passenger who is speaking with the remote user 30, carries the interfering noise of the voice of the driver and of the second passenger, carries at least part of the environmental noise and carries the third and fourth echoes of the remote user 30.
• the acoustic echo canceller 55 receives from the third environmental microphone 5-3 the third occupant signal S3_oc carrying the interfering noise of the voice of the driver, of the first and of the second passenger, carries at least part of the environmental noise and carries the fifth and sixth echoes of the remote user 30.
• the acoustic echo canceller 55 receives from the first headrest unit 1 the first input reference signal S1_ref_in carrying the first voice return signal of the remote user 30 who is speaking with the driver, and the acoustic echo canceller 55 also receives from the second headrest unit 10, the second input reference signal S2_ref_in carrying the second voice return signal of the remote user 30 who is speaking with the first passenger.
• the acoustic echo canceller 55 performs at instant t2 a reduction (at the limit, a cancellation) of the first, second, third, fourth, fifth and sixth echoes of the remote user 30 by using the received signal of the voice of the remote user 30 from the first and second input reference signals S1_ref, S2_ref.
• the acoustic echo canceller 55 the acoustic echo canceller 55:
• the source separator 56 receives on the first input terminal the voice signal of the driver, the interfering noise of the voice of the first and second passengers and at least part of the environmental noise, receives on the second input terminal the voice signal of the first passenger, the interfering noise of the voice of the driver and of the second passenger and at least part of the environmental noise, receives on the third input terminal the interfering noise of the voice of the driver, of the first and second passengers and at least part of the environmental noise, then the source separator 56 performs:
• the post-filtering and noise cancellation sub-unit 57 receives on the first input terminal the voice signal of the driver and at least part of the environmental noise, further receives on the second input the voice signal of the first passenger and at least part of the environmental noise, receives on the third input terminal at least part of the environmental noise, then performs a post-filtering of the voice signal of the driver and of the first passenger and a reduction (at the limit, cancellation) of said at least part of the environmental noise, thus generating on the first output terminal the first filtered signal S1_ft carrying the voice of the driver who is speaking with the remote user 30 and on the second output terminal the second filtered signal S2_ft carrying the voice of the first passenger who is speaking with the remote user 30.
• the selector 59 receives the selection signal S_sel indicative of the selection of the voice of the driver and of the first passenger, receives as input the first, second and third filtered signal S1_ft, S2_ft, S3_ft and transmits on the output terminal the internal output interface signal S_IDC_o_int equal to a multiplexing of the first filtered signal S1_ft carrying the voice of the driver who is speaking with the remote user 30 and of the second filtered signal S2_ft carrying the voice of the first passenger who is speaking with the remote user 30.
• the interface unit 40 receives as input the internal output interface signal S_IDC_o_int and generates as output the output interface signal S_IDC_o carrying the voice of the driver and of the first passenger who are speaking with the remote user 30.
• the remote user 30 receives the voice of the driver and of the first passenger, by means of a mobile radio network: in this way the remote user 30 listens to the voice of the driver of the vehicle and of the first passenger who are speaking with a good quality, since the voice of the driver received by the remote user 30 is not disturbed by the voice of the second passenger nor by the environmental noise within the vehicle, and since the voice of the first passenger received by the remote user 30 is not disturbed by the voice of the second passenger nor by the environmental noise in the vehicle.
• the invention is applicable also in case the voice communication is internal, i.e. it is performed between two occupants within the closed environment or in case there is a voice interaction between an occupant within the closed environment and a voice assistant, wherein said internal audio communication or said voice interaction can also be performed simultaneously with a voice communication between the remote user 30 and another occupant not engaged in internal voice communication.
• the acoustic echo canceller 55 is an acoustic echo/return canceller, i.e. it has the further function of cancelling a return of an echo containing the voice of a first occupant who is speaking, wherein said echo is generated due to the loudspeaker associated with the second occupant emitting the acoustic signal of the voice of the first occupant who is speaking, wherein the acoustic signal of the voice of the first occupant (emitted by the loudspeaker associated with the second occupant) is acquired by the environmental microphone associated with the first occupant who is speaking.
• the above considerations relating to the first operation are similarly applicable to the case where the driver is interacting with a voice assistant within the passenger compartment, with the difference that the remote user 30 is replaced by the voice assistant which can be realized internally to the user interface unit 40, thus the voice call between the driver and the remote user 30 is replaced by the voice interaction between the driver and the voice assistant and the voice signal of the remote user 30 is replaced by the voice signal generated automatically by the voice assistant.
• the system comprises at least two local units and a processing unit electrically connected to the at least two local units, wherein each local unit comprises at least one loudspeaker.
• the system further comprises at least two environmental microphones within the closed environment and associated with at least two respective occupants within the closed environment, each environmental microphone being connected to the processing unit.
• the at least two environmental microphones are configured to acquire a respective acoustic signal of the voice of an occupant, positioned in an audio communication zone within the closed environment, who is speaking with a remote user, is configured to acquire an interfering noise of the voice of at least one further occupant within the closed environment, and is configured to acquire an environmental noise present within the closed environment.
• the processing unit is configured to transmit, towards a first one of the at least two local units, a voice signal of the remote user.
• the first local unit is configured to receive the voice signal of the remote user and generate therefrom at least one driving signal for driving the at least one loudspeaker associated with the first local unit, in order to emit the acoustic field of the voice of the remote user directed towards said occupant and in order to emit the acoustic field of the voice of the remote user attenuated towards directions different from said occupant.
• the first local unit is configured to transmit, towards the processing unit, a return signal of the voice of the remote user who is speaking.
• the at least two environmental microphones are further configured to acquire a respective at least one echo of the voice of the remote user emitted by the at least one loudspeaker of the first local unit.
• the processing unit is configured to receive the return signal carrying the voice of the remote user, is configured to receive from the at least two environmental microphones the respective acoustic signal of the voice of the occupant, the interfering noise of the voice of the at least one further occupant, the environmental noise and the respective at least one echo of the voice of the remote user, and is configured to attenuate, as a function of the received signals, said respective at least one echo of the voice of the remote user, the interfering noise of the voice of the at least one further occupant and the environmental noise, generating as output an interface signal carrying the voice of the occupant.
• the method comprises the step a) of acquiring, by means of at least two environmental microphones, associated with at least two respective occupants within the closed environment, of an electronic audio communication system within the closed environment, at least one respective acoustic signal of the voice of an occupant, positioned in an audio communication zone within the closed environment, who is speaking with a remote user, acquiring an interfering noise of at least one further occupant within the closed environment, and acquiring an environmental noise present within the closed environment; it comprises step b) of acquiring, by means of at least one microphone of at least two respective local units of the electronic system, the interfering noise of the at least one further occupant and the environmental noise; it comprises step c) of receiving, at a first of the at least two local units, from a processing unit of the electronic system, a voice signal of the remote user and generating therefrom at least one driving signal for driving at least one loudspeaker associated with the first local unit, in order

Landscapes

• Health & Medical Sciences (AREA)
• Otolaryngology (AREA)
• Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Acoustics & Sound (AREA)
• Signal Processing (AREA)
• General Health & Medical Sciences (AREA)
• Fittings On The Vehicle Exterior For Carrying Loads, And Devices For Holding Or Mounting Articles (AREA)
• Circuit For Audible Band Transducer (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=92800148

Family Applications (1)

Country Status (1)

Citations (6)

• 2025
  • 2025-06-13 EP EP25182679.8A patent/EP4664924A1/de active Pending

Patent Citations (6)

Similar Documents

Legal Events