JP2017030671A - Noise reduction device, noise reduction method, and on-vehicle system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology of avoiding howling in a conversation auxiliary device and also hearing a conversation by the conversation auxiliary device more easily than in the conventional practice.SOLUTION: A noise reduction device for reducing noise caused by a vehicle includes an operation information detection part for detecting operation information of a conversation auxiliary device for helping a conversation of a speaker in a cabin, and a control part of the noise reduction device for executing noise reduction processing for reducing noise in accordance with the operation information of the conversation auxiliary device detected by the operation information detection part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a technique for reducing noise.

  There is a technique for reducing noise generated in a vehicle. For example, Patent Document 1 discloses a noise reduction device that forms a canceling sound having an opposite phase and equal sound pressure to noise. Further, for example, in Patent Document 2, based on a transfer characteristic coefficient representing a transfer characteristic from a speaker that outputs a control sound for reducing noise generated in a vehicle to an error microphone provided at a predetermined position in the vehicle interior of the vehicle. A vehicle noise reduction device that controls the noise in the vehicle interior by adaptively changing the control sound is disclosed.

  There is also a technology related to a conversation support device that supports conversation between talkers in a passenger compartment. For example, Patent Document 3 discloses a conversation support device that supports conversations between a plurality of talkers using a sound output device and a sound detection device provided near the head of the talker for each seat on which the talker sits. It is disclosed.

JP 7-168578 A JP 2008-239099 A JP 2010-163054 A

  There is a noise reduction device that outputs a cancellation sound and reduces noise generated in the vehicle. There is also a conversation assisting device that assists the conversation of a speaker in the passenger compartment. For example, in the conversation assist device, a conversation support device that supports conversation between speakers in the vehicle interior, or a call between a speaker in the vehicle interior and a speaker outside the vehicle realizes a so-called hands-free call. There are hands-free devices that assist speakers in the passenger compartment.

  Here, the conventional noise reduction device and the conventional conversation assistance device operate independently of each other. The conventional noise reduction device merely outputs a canceling sound according to the noise at the time of noise. On the other hand, in order to make it easier for the conversation assisting device to hear the speaker's voice during noise, it is conceivable to increase the volume of the speaker of the conversation assisting device. However, the conversation assisting device may cause howling if the volume is increased too much. Therefore, there is a limit to the volume that can be raised by the conversation assistance device.

  It is an object of the present invention to provide a technique for avoiding howling in a conversation assisting device and making conversations by the conversation assisting device easier to hear than in the past.

  In the present invention, in order to solve the above-described problem, the noise reduction device and the conversation assistance device are linked together, and the noise reduction processing by the noise reduction device is executed according to the operation state of the conversation assistance device.

More specifically, the present invention is a noise reduction device that reduces noise generated in a vehicle, and an operation information detection unit that detects operation information of a conversation assistance device that assists a conversation of a speaker in a vehicle interior; And a control unit of a noise reduction device that executes a noise reduction process for reducing noise according to the operation information of the conversation assistance device detected by the operation information detection unit.

  According to the noise reduction device according to the present invention, it is possible to reduce the noise during the conversation by the conversation assistance device by executing the noise reduction processing according to the operation information of the conversation assistance device. As a result, it is possible to make it easier to hear the conversation by the conversation assistance device than in the past. In addition, since it is not necessary to increase the volume of the conversation assistance device more than necessary, it is possible to suppress howling that is a concern by raising the volume of the conversation assistance device. The conversation assist device includes a conversation support device that supports conversation between speakers in the vehicle interior, and a so-called hands-free call in a conversation between a speaker in the vehicle interior and a speaker outside the vehicle interior. A hands-free device that assists the speaker is illustrated. Noise is associated with the traveling of the vehicle and includes a squeaking noise, road noise, wind noise, and the like in the passenger compartment. The muffled noise is generated by resonance of a specific frequency in the vehicle interior, which is a closed space, because the vibration of the engine is transmitted to the vehicle interior. Road noise is caused by contact friction between vehicle tires and the road. Wind noise is generated when the vehicle cuts outside air. The noise reduction processing includes processing for reducing noise by outputting from a speaker a canceling sound (also referred to as control sound) that cancels the noise according to the noise.

  Here, the motion information detection unit detects information about on / off of the conversation assisting device as the operation information of the conversation assisting device, and the control unit of the noise reduction device detects that the conversation assisting device is on. In this case, the noise reduction processing may be executed so that the noise reduction effect is greater than when the conversation assistance device is off. As a result, howling in the conversation assisting device can be avoided, and conversation by the conversation assisting device can be made easier to hear than in the past. The noise reduction effect is an effect that noise is reduced by executing the noise reduction processing. When the noise reduction effect is large, the noise heard by the speaker is reduced, and as a result, the conversation becomes easy to hear. In addition, the control part of the said noise reduction apparatus should just perform a noise reduction process, when the said conversation assistance apparatus is OFF.

  In addition, for example, the control unit of the noise reduction device executes the noise reduction processing according to noise, and the noise reduction effect is greater when the conversation assist device is on than when the conversation assist device is off. The noise reduction processing may be changed so that becomes even larger. According to the present invention, when the conversation assistance device is on, the noise reduction processing is changed so that the noise reduction effect is further increased. As a result, howling in the conversation assisting device can be avoided, and conversation by the conversation assisting device can be made easier to hear than before.

  Here, for example, by opening a window, a sound other than the originally assumed noise may enter the vehicle compartment from outside the vehicle. If a noise other than the originally assumed noise is detected and the noise reduction device executes the noise reduction processing, the noise reduction effect may not be sufficiently exhibited, and conversely, the noise may increase. Since such a case is malfunctioning, the noise reduction device can stop the noise reduction processing. However, when such a malfunction occurs, for example, if the noise reduction process is performed so that the noise reduction effect is maximized, it takes time to stop the noise reduction process. Therefore, the conventional noise reduction device executes the noise reduction processing with the noise reduction effect deliberately suppressed so that the noise reduction processing can be quickly stopped in the case of malfunction due to opening a window or the like. On the other hand, when the conversation assistance device is on, it is assumed that the window is closed. Therefore, the noise reduction device according to the present invention executes the noise reduction processing so that the noise reduction effect is maximized on the assumption that malfunctions due to window opening or the like are unlikely to occur when the conversation assist device is on. May be. For example, the control unit of the noise reduction device detects window opening / closing information related to the opening / closing state of the vehicle window, and executes noise reduction processing according to the operation information of the conversation assisting device only when the window is closed. You may make it do. As a result, it is possible to avoid a situation where the noise is increased in the case of malfunction.

  Here, the present invention can be specified as a noise reduction method. For example, the present invention is a noise reduction method for reducing noise generated in a vehicle, the operation information detecting step for detecting operation information of a conversation assistance device for assisting a conversation of a speaker in a vehicle interior, and the operation information And a noise control step for executing a noise reduction process for reducing noise according to the operation information of the conversation assistance device detected in the detection step. A process including these steps can be executed by a computer, for example.

  According to the noise reduction method of the present invention, it is possible to avoid howling in the conversation assisting device and make it easier to hear the conversation by the conversation assisting device than in the past.

  In addition, the present invention can be specified as an in-vehicle system including the above-described noise reduction device and conversation assistance device. For example, the present invention is an in-vehicle system that includes a noise reduction device that reduces noise generated in a vehicle and a conversation assistance device that assists a conversation of a speaker in a vehicle interior, and the noise reduction device includes: A noise reduction unit that reduces noise according to the operation information detected by the operation information detection unit that detects the operation information of the conversation assistance device that assists the conversation of the speaker And a control unit of a noise reduction device that executes processing.

  In addition, this invention can also be specified as a program which implement | achieves the noise reduction method mentioned above. Furthermore, the present invention may be a computer-readable recording medium that records such a program. In this case, the function can be provided by causing the computer or the like to read and execute the program of the recording medium. Note that a computer-readable recording medium is a recording medium that accumulates information such as data and programs by electrical, magnetic, optical, mechanical, or chemical action and can be read from a computer or the like. Say.

  ADVANTAGE OF THE INVENTION According to this invention, while avoiding the howling in a conversation assistance apparatus, the technique which makes it easier to hear the conversation by a conversation assistance apparatus than before can be provided.

FIG. 1 shows a configuration of an in-vehicle system according to the embodiment. FIG. 2 is a layout diagram of microphones and the like in the in-vehicle system according to the embodiment. FIG. 3 is a flowchart of the conversation support process according to the embodiment. FIG. 4 is a flowchart of noise reduction processing according to the embodiment. FIG. 5 shows a noise reduction processing flow in the normal mode. FIG. 6 is a diagram for explaining the relationship between the speaker volume that is not howling and the speaker volume necessary for improving listening. FIG. 7 is a diagram for explaining the relationship between the speaker volume that is not howling and the speaker volume that is necessary for improving listening when the noise reduction effect is improved.

  Next, an embodiment of an in-vehicle system including a noise reduction device and a conversation assistance device according to the present invention will be described based on the drawings. The following embodiments are exemplifications, and the technical scope of the present invention is not limited thereto.

<Outline of in-vehicle system>
FIG. 1 shows a configuration of an in-vehicle system according to the embodiment. FIG. 2 is a layout diagram of microphones and the like in the in-vehicle system according to the embodiment. The in-vehicle system 1 is mounted on a vehicle 100 and includes a conversation support device 3 that supports conversation between speakers in a passenger compartment 101 and a noise reduction device 2 that reduces noise generated in the vehicle 100.

  The in-vehicle system 1 further includes a microphone 4, a microphone amplifier 81, a DSP (Digital Signal Processor) 83, a main amplifier 84, and a speaker 6. The microphone 4 collects sound in the passenger compartment 101. The microphone 4 also functions as an error microphone. The microphone amplifier 81 adjusts the gain of the audio signal collected by the microphone 4 and converted into a digital signal by an A / D converter (not shown). The DSP 83 performs sound processing on the sound signal whose gain has been adjusted. The main amplifier 84 performs sound processing in the DSP 83 and amplifies the sound signal converted into an analog signal by a D / A converter (not shown). The speaker 6 outputs sound. Further, the speaker 6 outputs a cancel sound (also referred to as a control sound) having a phase opposite to that of the noise and having a constant sound pressure in accordance with the noise. The microphone 4 and the speaker 6 are simply referred to as the microphone 4 and the speaker 6 when it is not necessary to distinguish between them. Details of the microphone 4 and the speaker 6 will be described later.

  As an example, the DSP 83 generates a cancel sound signal (hereinafter also referred to as a cancel signal) that cancels noise. For example, the DSP 83 convolves a filter coefficient with a noise voice signal corresponding to noise to generate a cancel signal that cancels the noise, an error signal from the error microphone (for example, the driver's seat microphone 41), and the cancel signal. In addition, a speaker functioning as a mute speaker (for example, driver's seat speaker 61) and an error microphone (for example, driver's seat microphone 41) having been corrected for transmission characteristics are input so that the level of the error signal is minimized. A coefficient update unit that updates the filter coefficient of the adaptive filter, a transfer characteristic simulation correction unit that simulates the transfer characteristic and corrects the cancel signal, and a noise voice signal that is a control target of the adaptive filter by combining the cancel signal and the error signal And an adding unit that reproduces

  The vehicle 100 on which the in-vehicle system 1 is mounted includes a so-called three-row seat. The conversation support device 3 is configured so that the conversation between the driver seated in the driver's seat 111 or a passenger seated in the passenger seat 112 and the passenger seated in the third row seat 114 can be easily heard from each other. The setting of the speaker 6 and the volume output from the speaker 6 are adjusted. In addition, the noise reduction device 2 is configured so that the conversation between the driver sitting in the driver seat 111 or the passenger seat 112 and the passenger sitting in the third row seat 114 can be heard more easily. The noise reduction process for reducing the noise is executed according to the noise, and the noise reduction process is changed according to the information on the on / off of the conversation support device 3.

As shown in FIG. 2, the so-called third row seat includes a driver seat 111, a passenger seat 112, a second row seat 113, and a third row seat 114. A microphone 4, a speaker 6, and a switch 7 are installed around the driver seat 111 and the passenger seat 112 and around the third row seat 114. Around the driver's seat 111, a driver's seat microphone 41, a driver's seat noise detection microphone 45, a driver's seat speaker 61, and a driver's seat switch 71 are installed. The driver's seat microphone 41 is installed on the headrest of the driver's seat 111 and collects the voice of the driver sitting on the driver's seat 111 or the passenger's voice sitting on the passenger seat 112. The installation position is not particularly limited, but the driver's seat microphone 41 is preferably installed at a position close to the driver's (speaker) 's mouth. The noise detection microphone 45 in the driver's seat is installed on the headrest of the driver's seat 111 and detects noise in the passenger compartment 101 near the driver's seat 111. The installation position is not particularly limited, but the noise detection microphone 45 in the driver's seat is preferably installed at a position close to the driver's (speaker) ear. The noise detection microphone 45 in the driver's seat also functions as an error microphone that detects residual sound as a result of interference between cancellation sound and noise. The driver's seat speaker 61 is installed at a door in the vicinity of the driver's seat 111 and functions as an acoustic speaker that outputs sound in the passenger compartment 101, and is used for a driver sitting in the driver's seat 111 or a passenger sitting in the passenger's seat 112. It functions as an individual speaker that provides individual sounds. Further, the driver's seat speaker 61 has a function of outputting a canceling sound that cancels out noise. The driver's seat switch 71 is installed at a door near the driver's seat 111 so that a conversation between a driver sitting on the driver's seat 111 or a passenger sitting on the passenger's seat 112 and a passenger sitting on the third row seat 114 can be communicated with each other. Toggle conversation support processing for easy listening.

  Around the passenger seat 112, a passenger seat microphone 42, a passenger seat noise detection microphone 46, a passenger seat speaker 62, and a passenger seat switch 72 are installed. The passenger seat microphone 42 is installed at the headrest of the passenger seat 112 and collects a voice of a passenger seated in the passenger seat 112 or a driver seated in the driver seat 111. Although the installation position is not particularly limited, the passenger seat microphone 42 is preferably installed at a position close to the mouth of the passenger (speaker) sitting on the passenger seat 112. The passenger seat noise detection microphone 46 is installed at the headrest of the passenger seat 112 and collects noise in the passenger compartment 101 in the vicinity of the passenger seat 112. The installation position is not particularly limited, but the noise detection microphone 46 in the passenger seat is preferably installed at a position close to the ear of the passenger (speaker) sitting on the passenger seat 112. The passenger seat noise detection microphone 46 also functions as an error microphone. The passenger seat speaker 62 is installed at a door in the vicinity of the passenger seat 112 and functions as an acoustic speaker that outputs sound in the passenger compartment 101, and also serves as a passenger seated in the passenger seat 112 or a driver seated in the driver seat 111. It functions as an individual speaker that provides individual sounds. Further, the passenger seat speaker 62 has a function of outputting a canceling sound for canceling out noise. The passenger seat switch 72 is installed at a door near the passenger seat 112, and conversation between the passenger seated in the passenger seat 112 or the driver seated in the driver seat 111 and the passenger seated in the third row seat 114 is mutually performed. Toggle conversation support processing for easy listening.

  Around the third row seat 114, third row seat microphones 43 and 44, third row seat noise detection microphones 47 and 48, third row seat speakers 63 and 64, and third row seat switches 73 and 74 are installed. ing. The third row seat microphones 43 and 44 are installed on the left and right headrests of the third row seat 114, respectively, and collect voices of passengers sitting on the third row seat 114. The installation position is not particularly limited, but the third row seat microphone 4 is preferably installed at a position close to the passenger's (speaker) mouth. The third row seat noise detection microphones 47 and 48 are installed on the left and right headrests of the third row seat 114, respectively, and detect noise in the passenger compartment 101 in the vicinity of the third row seat 114. Although the installation position is not particularly limited, it is preferable that the noise detection microphones 47 and 48 in the third row seat be installed at a position close to the ears of the passenger (speaker). The noise detection microphones 47 and 48 in the third row seat also function as error microphones. The third row seat speakers 63 and 64 are installed on the left and right doors in the vicinity of the third row seat 114, function as acoustic speakers that output sound into the passenger compartment 101, and are seated on the third row seat 114. It functions as an individual speaker that provides individual sounds to passengers. Further, the third row seat speakers 63 and 64 also have a function of outputting a canceling sound that cancels the noise. The third row seat switches 73 and 74 are installed on the left and right doors in the vicinity of the third row seat 114, and are installed on the driver seated in the driver's seat 111 or the passenger seated in the passenger seat 112 and the third row seat 114. Toggle conversation support processing on / off to make it easier to hear each other's conversations with the passengers who are seated.

  In the present embodiment, a microphone that collects the voices of the driver and passengers and a microphone that detects noise are installed separately. Since human voice and noise have different frequency bands, this makes it possible to detect sound more accurately. However, these microphones may be shared by expanding the band of one of the speakers.

<Conversation support device>
The conversation support device 3 includes a control unit 33 of the conversation support device. The control unit 33 of the conversation support device includes a driver seated in the driver's seat 111 or a passenger seated in the passenger seat 112 and the third row seat. A conversation support process for adjusting the settings of the microphone 4 and the speaker 6 and adjusting the sound volume output from the speaker 6 is executed so that conversations with the passengers sitting at 114 are easily heard from each other. Specifically, the CPU (Central Processing Unit) 3 of the conversation support device that constitutes the conversation support device 3.
By executing the conversation support processing program 1 recorded in the memory 32 of the conversation support apparatus, the conversation support process is realized. In addition to the conversation support processing program, the memory 32 of the conversation support apparatus records a predetermined value for the volume of sound output from the speaker 6 during execution of the conversation support process. The predetermined value of the volume is determined in advance as a value that does not perform howling.

  Here, FIG. 3 shows a flowchart of the conversation support processing according to the embodiment. The conversation support process is started when the accessory power supply of the vehicle 100 is turned on or the start button of the conversation support process is pressed. The start button of the conversation support process can be displayed as a reception button on, for example, an audio device (not shown) or a touch panel display of a navigation device.

  In step S01, the control unit 33 of the conversation support apparatus determines whether at least one of the driver seat switch 71, the passenger seat switch 72, and the third row seat switches 73 and 74 is turned on. When at least one of these switches is turned on, the process proceeds to step S02. On the other hand, when these switches (for example, the driver's seat switch 71) are off, the process returns to step S01.

  In step S02, the control unit 33 of the conversation support apparatus sets a microphone (for example, driver's seat microphone 41) and a speaker (for example, driver's seat speaker 61) to be used. For example, when the driver's seat switch 71 is turned on, the control unit 33 of the conversation support apparatus turns on the driver's seat microphone 41, the passenger's seat microphone 42, the third-row seat microphones 43 and 44, the driver's seat speaker 61, and the passenger's seat speaker 62. All the third-row seat speakers 63 and 64 are turned on. In this embodiment, when any switch (for example, the driver's seat switch 71) is turned on, a speaker (for example, the driver's seat speaker 61) and a microphone (for example, the driver's seat microphone 41) used in the conversation support process are connected. All are turned on, but only the speaker (for example, the driver's seat speaker 61) and the microphone (for example, the driver's seat microphone 41) of the seat with the switch (for example, the driver's seat switch 71) turned on may be turned on. Good.

  Next, in step S03, the control unit 33 of the conversation support apparatus divides the interior of the passenger compartment 101 into the front and the rear, and when sounds are collected by the driver's seat microphone 41 and the passenger's seat microphone 42 positioned in the front, Sound is output from the third row seat speakers 63 and 64 located at the rear. Further, the control unit 33 of the conversation support apparatus outputs sound from the driver seat speaker 61 and the passenger seat speaker 62 located in front when the sound is collected by the third row seat microphones 43 and 44 located in the rear. To do. The control unit 33 of the conversation support apparatus reads a default value of the volume from the memory 32 of the conversation support apparatus, and based on the read default value of the volume, the volume of the collected sound using an amplifier or the like is set so that no howling occurs. adjust. The control unit 33 of the conversation support device outputs the sound after adjusting the volume from the driver seat speaker 61 and the passenger seat speaker 62 or the third row seat speakers 63 and 64. In the present embodiment, the conversation is supported by dividing the interior of the passenger compartment 101 into the front and the rear. However, the conversation may be supported by dividing each seat. The driver's seat microphone 41 and the passenger's seat microphone 42 may be shared microphones and installed in front of the ceiling. Alternatively, the third row seat speakers 63 and 64 may be shared microphones and installed behind the ceiling.

Next, in step S04, the control unit 33 of the conversation support apparatus determines whether at least one of the driver seat switch 71, the passenger seat switch 72, and the third row seat switches 73 and 74 is turned off. When at least one of these switches (for example, the driver's seat switch 71) is turned off, the conversation support process ends. On the other hand, when these switches (for example, the driver's seat switch 71) remain on, the process returns to step S03 and the conversation support process is continued. In this embodiment, when any of the switches (for example, the driver's seat switch 71) is turned off, a speaker (for example, the driver's seat speaker 61) and a microphone (for example, the driver's seat microphone 41) used in the conversation support process are connected. All conversations are turned off and the conversation support process ends.
For example, only the speaker (for example, the driver's seat speaker 61) and the microphone (the driver's seat microphone 41) of the seat for which the driver's seat switch 71) is turned off may be turned off.

<Noise reduction device>
The noise reduction device 2 includes a control unit 23 of the noise reduction device and an operation information detection unit 24. The control unit 23 of the noise reduction device executes a noise reduction process for reducing noise according to the noise. Further, the noise reduction device 2 performs a change process for changing the noise reduction process in accordance with the information on the on / off of the conversation support device 3 detected by the operation information detection unit 24. Specifically, the noise reduction processing is realized by the CPU 21 that is a computer of the noise reduction device constituting the noise reduction device 2 executing a noise reduction processing program recorded in the memory 22 of the noise reduction device. Further, the CPU 21 of the noise reduction device executes the change processing program for changing the noise reduction processing recorded in the memory 22 of the noise reduction device, whereby the noise reduction processing is changed. The information on the on / off of the conversation support device 3 is acquired by the operation information detection unit 24 as the operation information of the conversation support device 3. The motion information detection unit 24 can be configured by, for example, a signal detection circuit that detects an on / off signal of the conversation support device 3.

  In the noise reduction process, the speaker 6 (for example, the driver's seat speaker 61) outputs a canceling sound (also referred to as a control sound) that cancels the noise according to the noise. In the noise reduction processing, the microphone 4 (for example, the noise detection microphone 45 in the driver's seat) functions as an error microphone while detecting noise (for example, a booming sound). Further, the microphone 4 (for example, the noise detection microphone 45 in the driver's seat), as other noise, for example, road noise (noise caused by contact friction between the tire of the vehicle 100 and the road) and wind noise (the vehicle 100 is outside). The noise generated by cutting the air is detected.

  Here, FIG. 4 shows a flowchart of the noise reduction processing according to the embodiment. Hereinafter, the change process for changing the noise reduction process will be described together with the noise reduction process. The noise reduction process and the change process for changing the noise reduction process are started when the accessory power supply of the vehicle 100 is turned on or the start button of the noise reduction process is pressed. The start button of the noise reduction process can be displayed as a reception button on, for example, an audio device (not shown) or a touch panel display of a navigation device.

  In step S <b> 11, the control unit 23 of the noise reduction device acquires information regarding on / off of the conversation support device 3 as operation information of the conversation support device 3. Information regarding on / off of the conversation support device 3 may be acquired by the operation information detection unit 24 from the driver seat switch 71, the passenger seat switch 72, and the third row seat switches 73 and 74. You may acquire from the part 33. FIG.

  Next, in step S12, the control unit 23 of the noise reduction device determines whether or not the conversation support device 3 is turned on. When conversation support device 3 is turned on (YES in step S12), the process proceeds to step S13. On the other hand, when conversation support device 3 is off (NO in step S12), the process proceeds to step S14. Before executing the noise reduction processing in the high mode, the control unit 23 of the noise reduction device detects window opening / closing information related to the opening / closing state of the window of the vehicle 100, and the conversation is performed only when all the windows are closed. High mode noise reduction processing corresponding to the operation information of the support device 3 may be executed. As a result, it is possible to avoid a situation where the noise is increased in the case of malfunction.

In step S13, the control unit 23 of the noise reduction device executes high-mode noise reduction processing. On the other hand, in step S14, the control unit 23 of the noise reduction device executes normal mode noise reduction processing. The noise reduction processing in the high mode reduces the noise so as to increase the noise reduction effect compared to the noise reduction processing in the normal mode, that is, the noise is smaller and the conversation by the conversation support device 3 is easier to hear. Processing is executed. When the noise reduction process in the normal mode or the noise reduction process in the high mode ends, the noise reduction process ends.

Here, FIG. 5 shows a noise reduction processing flow in the normal mode. In step S21, the control unit 23 of the noise reduction device acquires noise information. The noise information includes a muffled sound, road noise, and wind noise noise signal. The control unit 23 of the noise reduction device acquires vehicle speed data and engine rotation data from an ECU (Electronic Control Unit) (not shown).
A noise voice signal based on speed data and engine rotation data can be recorded for each type of noise in the memory 22 of the noise reduction device. The control unit 23 of the noise reduction device calculates a noise voice signal for each noise (boom sound, road noise, wind noise) from the acquired vehicle speed data and engine rotation data. The noise voice signal may be calculated from noise detected by each noise detection microphone installed in the vehicle interior 101. In addition, a noise voice signal is calculated from the speed data and the engine rotation data, and the noise voice signal is calculated separately based on the noise detected by each noise detection microphone installed in the passenger compartment 101, and the two are compared. It may be. Further, the noise voice signal calculated from the speed data and the engine rotation data may be corrected according to the comparison result.

  In step S <b> 22, the control unit 23 of the noise reduction device determines a cancel sound based on the noise information (calculated noise voice signal) and outputs the cancel sound from the speaker 6. In the memory 22 of the noise reduction device, a control program in which a filter coefficient for generating a cancel sound corresponding to the noise voice signal is set can be recorded. For example, the control unit 23 of the noise reduction apparatus determines a cancel signal by applying this control program to the DSP 83 and outputs a cancel sound from a speaker (for example, the driver's seat speaker 61).

  Next, in step S23, the control unit 23 of the noise reduction device acquires residual sound as a result of interference between the canceling sound and the noise. The residual sound can be acquired by, for example, a noise detection microphone 45 in the driver's seat that functions as an error microphone.

  In step S24, the control unit 23 of the noise reduction device corrects and outputs the cancel signal based on the acquired residual sound. For example, the transfer characteristic between the speaker (for example, the driver's seat speaker 61) and the error microphone (for example, the noise detection microphone 45 in the driver's seat) is corrected to the error signal and the cancel signal from the error microphone (for example, the driver's seat microphone 41). Then, the filter coefficient of the adaptive filter is updated so that the level of the error signal is minimized, and the cancel signal is corrected by simulating the transfer characteristic. A cancel sound corresponding to the corrected cancel signal is output from the speaker 6, and the noise reduction process in the normal mode is completed.

  The noise reduction processing in the high mode reduces the noise so as to increase the noise reduction effect compared to the noise reduction processing in the normal mode, that is, the noise is smaller and the conversation by the conversation support device 3 is easier to hear. Processing is executed. The process flow is basically the same as the noise reduction process in the normal mode described above. For example, the control unit 23 of the noise reduction device compares the noise reduction process in the high mode with the noise reduction process in the normal mode. Therefore, a control program in which a filter coefficient for generating a cancellation sound is set is applied to the DSP 83 so that the noise reduction effect is increased.

  For example, in the high mode noise reduction processing, the control unit 23 of the noise reduction device generates a cancel signal having a higher intensity than the noise reduction processing in the normal mode by the DSP 83, and a speaker (for example, the driver's seat speaker 61). Can output a canceling sound. As a result, for example, it is possible to effectively enhance the noise reduction effect of the engine noise that is relatively low in the frequency band.

<Effect>
Here, FIG. 6 shows a diagram for explaining the relationship between the speaker volume that is not howling and the speaker volume necessary for improving listening. FIG. 7 is a diagram for explaining the relationship between the speaker volume that is not howling and the speaker volume that is necessary for improving listening when the noise reduction effect is improved. In FIG. 6, the speaker volume necessary for improving listening is higher than the speaker volume that is not howling. On the other hand, in FIG. 7, since the noise reduction effect is increased, the speaker volume necessary for improving listening is within the speaker volume that does not perform howling. FIG. 7 corresponds to the relationship between the speaker volume that is not howling and the speaker volume that is necessary for improving listening in the case where the noise reduction effect is improved in the in-vehicle system 1 according to the embodiment. That is, according to the noise reduction device 2 according to the embodiment, the noise can be reduced during the conversation by the conversation support device 3 by executing the noise reduction process according to the operation information of the conversation support device 3. . As a result, the conversation by the conversation support apparatus 3 can be made easier to hear than in the past. Further, since it is not necessary to increase the volume of the conversation support apparatus 3 more than necessary, it is possible to suppress howling that is a concern by increasing the volume of the conversation support apparatus 3.

  In the above-described embodiment, the conversation support device 3 that supports conversation between speakers in the passenger compartment 101 has been described as an example of the conversation assistance device according to the present invention. The conversation support process executed by the conversation support apparatus 3 is merely an example. Further, in place of the conversation support device 3, a hands-free call is realized in a call between a speaker in the passenger compartment 101 and a speaker outside the vehicle 100 to assist the speaker in the passenger compartment 101. Other devices such as a free device may be used.

  Moreover, the noise reduction process performed with the noise reduction apparatus 2 is only an example. The noise reduction device 2 only needs to perform noise reduction processing according to the operation information of the conversation support device 3, and the existing technology can be applied to the content of the noise reduction processing.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these, and can include combinations thereof as much as possible.

DESCRIPTION OF SYMBOLS 1 ... In-vehicle system 2 ... Noise reduction apparatus 21 ... CPU of noise reduction apparatus
DESCRIPTION OF SYMBOLS 22 ... Memory of noise reduction apparatus 23 ... Control part of noise reduction apparatus 24 ... Detection part 3 of operation information ... Conversation support apparatus 31 ... CPU of conversation support apparatus
32 ... Memory of conversation support device 33 ... Control unit 4 of conversation support device ... Microphone 6 ... Speaker 7 ... Switch 81 ... Microphone amplifier 83 ... DSP
84 ... Main amplifier 100 ... Vehicle 101 ... Vehicle 111 ... Driver seat 112 ... Passenger seat

Claims (6)

A noise reduction device for reducing noise generated in a vehicle,
An operation information detection unit for detecting operation information of a conversation assistance device that assists the conversation of a speaker in the vehicle interior;
In accordance with the operation information of the conversation assistance device detected by the operation information detection unit, a control unit of the noise reduction device that executes noise reduction processing to reduce noise,
A noise reduction device comprising: The operation information detection unit detects information about on / off of the conversation assisting device as the operation information of the conversation assisting device,
The control part of the said noise reduction apparatus performs a noise reduction process so that a noise reduction effect may become large when the said conversation assistance apparatus is on compared with the case where the said conversation assistance apparatus is off. The noise reduction device described.   The control unit of the noise reduction device executes the noise reduction processing according to noise, and the noise reduction effect is further increased when the conversation assistance device is on compared to when the conversation assistance device is off. The noise reduction device according to claim 2, wherein the noise reduction processing is changed.   The control unit of the noise reduction device detects window opening / closing information related to the opening / closing state of the window of the vehicle, and the operation of the conversation assistance device detected by the operation information detection unit only when the vehicle is closed The noise reduction device according to any one of claims 1 to 3, wherein a noise reduction process for reducing noise is executed in accordance with information. A noise reduction method for reducing noise generated in a vehicle,
An operation information detection step for detecting operation information of a conversation assistance device for assisting a conversation of a speaker in the vehicle interior;
A noise control step for executing a noise reduction process for reducing noise according to the operation information of the conversation assistance device detected in the detection step of the operation information;
Noise reduction method including An in-vehicle system comprising a noise reduction device that reduces noise generated in a vehicle and a conversation assistance device that assists a conversation of a speaker in a vehicle interior,
The noise reduction device is:
An operation information detection unit for detecting operation information of a conversation assistance device that assists the conversation of a speaker in the vehicle interior;
In accordance with the operation information of the conversation assistance device detected by the operation information detection unit, a control unit of the noise reduction device that executes noise reduction processing to reduce noise,
In-vehicle system including

Images