JP2011102984A - Navigation device, voice recognition method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To direct the directional axis of a voice input microphone to a sound source. <P>SOLUTION: The navigation device includes: a microphone system which has a plurality of voice input microphones, and a voice signal generation part for adding delays to output signals from the plurality of microphones and adding together the signals having the delays added thereto to generate a voice signal, and in which a directional axis is changed by changing the delay amounts added to the output signals; a delay amount selection part for selecting, on the basis of the output level of a sample voice signal obtained by adding together the signals of sample delays added to the output signals from the plurality of microphones, one of a plurality of combinations of the delay amounts added to the output signals; a recognition part for recognizing the voice signal generated by using the selected delay amounts; and a control unit for controlling the operation of the device on the basis of the recognition result of the recognition part. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an in-vehicle device, and more particularly to a car navigation system having a voice recognition function.

Car navigation systems using GPS (Global Positioning System) have become widespread. This car navigation system includes a display unit (generally called a monitor) that displays map information and other information, a main body that houses an arithmetic processing unit and the like, a remote controller for inputting control information to the car navigation system, and the like It has. Recently, a car navigation system including a voice input device having a voice recognition function has been put into practical use as a means for inputting control information in addition to a remote control. A car navigation system equipped with this voice input device is provided with a microphone for voice input. Conventionally, this microphone is attached to, for example, a dashboard, a steering column, a sun visor, an A-pillar portion, etc. in a vehicle interior. The microphone is connected to a microphone cable drawn from the main body of the car navigation system. The main body of a car navigation system is often installed in a trunk room, not in the passenger compartment. Therefore, in a car navigation system equipped with a voice input device, a microphone cable is pulled out from a trunk room, and a microphone is attached on a dashboard or the like in a vehicle cabin as described above. Therefore, the required length of the microphone cable has reached 7 m. In addition, there is a problem that the work of wiring the microphone cable is complicated.

  It has been proposed and put to practical use in a voice input device of a car navigation system, in addition to a voice input microphone, a noise microphone for inputting a noise signal. The signal input to the audio input microphone is a signal in which an audio signal and a noise signal are mixed, while the signal input to the noise microphone is exclusively a noise signal. Accordingly, only the audio signal can be extracted by subtracting the signal input to the noise microphone from the signal input to the audio input microphone. However, providing two microphones, a voice input microphone and a noise microphone, is disadvantageous in terms of cost. Therefore, it is desirable that the S / N is good with one microphone.

  A voice input device capable of solving such problems is disclosed in Japanese Patent Laid-Open No. 10-11084. The voice input device disclosed in Japanese Patent Laid-Open No. 10-11084 is a voice input device for an in-vehicle navigation system having a navigation remote controller for performing remote control and a microphone for inputting voice for performing control using voice recognition. In the navigation remote controller, the microphone is provided. In the voice input system disclosed in Japanese Patent Laid-Open No. 10-11084, a microphone is provided in a wireless remote controller for inputting a control signal of a car navigation system, so that it is not necessary to perform wiring work for a microphone cable. . In addition, when the user performs voice input, the user can speak with the remote controller with a built-in microphone close to the mouth. Therefore, there is an advantage that it is hardly affected by noise.

Japanese Patent Laid-Open No. 10-11084

  As described above, the proposal of Japanese Patent Application Laid-Open No. 10-11084 in which a microphone is incorporated in a wireless remote controller is useful for solving the conventional problems. However, in order to input voice to the wireless remote controller with built-in microphone, the user needs to have the wireless remote controller. When voice input is performed while the vehicle is running, there is a risk of impeding driving operations. Accordingly, it is an object of the present invention to provide an in-vehicle device, particularly a car navigation system, which does not require a long cable for a microphone and does not require a microphone cable wiring operation or is simple. It is another object of the present invention to provide an in-vehicle device, particularly a car navigation system, that does not hinder driving operation during voice input.

  In order to solve the above-described problem, according to an aspect of the present invention, a plurality of microphones for audio input and a signal added with the delay are added to each of output signals from the plurality of microphones. An audio signal generation unit that generates an audio signal added to the microphone system, the microphone system in which the directivity axis is changed by changing the delay amount added to the output signal, and the output signals from the plurality of microphones A delay amount that selects one delay amount combination from among a plurality of combinations of delay amounts to be added to each of the above output signals, based on the output level of the sample audio signal obtained by adding the signals to which the sample delay has been added. Generated by using a combination of the selection unit and the delay amount selected by the delay amount selection unit. It has a recognition unit for recognizing voice signals, and a control unit for controlling the operation of the device based on the recognition result of the recognition unit, the navigation apparatus is provided.

  The delay amount selection unit may select a combination of the delay amounts having the highest output level.

  A storage unit that stores the combination of the delay amounts determined by the delay amount determination unit in association with the speaker as the sound source; and the audio signal generation unit associates with the designated speaker. The audio signal may be generated using a combination of delay amounts stored in the storage unit.

  The delay amount selection unit may detect the output level for a plurality of combinations of the delay amounts, and select the combination of the delay amounts with the highest output level.

  The output signals from the plurality of microphones are respectively input to the sound source estimation system having the delay amount selection unit and the output signal system having the audio signal generation unit, the recognition unit, and the control unit. The delay amount selection unit may execute the delay amount combination selection process during a period in which the control unit performs control based on the recognition result in the output signal system.

  The plurality of microphones may be arranged at equal intervals.

  In order to solve the above-described problem, according to another aspect of the present invention, a step of acquiring sound by a plurality of microphones, a step of adding a sample delay to output signals from the plurality of microphones, and the sample A step of generating a sample audio signal obtained by adding the signals to which the delay has been added, a step of detecting an output level of the sample audio signal, and a delay amount to be added to each of the output signals based on the output level A step of selecting a combination, a step of adding a delay to each of the output signals from the plurality of microphones based on the selected combination of the delay amounts, and adding each signal to which the delay has been added A step of generating an audio signal and a step of recognizing the audio signal. And-up, based on the result of the recognition including the steps of controlling the operation of the apparatus, the speech recognition method is provided.

  In order to solve the above problems, according to another aspect of the present invention, a computer adds a delay to each of a plurality of microphones for voice input and an output signal from the plurality of microphones. An audio signal generation unit that generates an audio signal obtained by adding the added signals, and a microphone system in which a directivity axis is changed by changing a delay amount added to the output signal; Based on the output level of the sampled audio signal obtained by adding the signal obtained by adding the sample delay to the output signal from the microphone, one delay amount is selected from among a plurality of combinations of delay amounts added to each of the output signals. A combination of a delay amount selection unit for selecting a combination and a delay amount selected by the delay amount selection unit. A program for functioning as a navigation device is provided, which includes a recognition unit for recognizing the voice signal generated by using the control unit and a control unit for controlling the operation of the device based on the recognition result of the recognition unit. .

  The inventor of the present invention paid attention to the use of a monitor as a target for drawing out a microphone cable. In a car navigation system, a monitor is usually mounted on a dashboard. Therefore, even if the microphone cable is pulled out from the monitor and the microphone is mounted on the dashboard, for example, the microphone cable can be shorter than the conventional one and the wiring work is very simple. In addition to the dashboard, the microphone pulled out from the monitor can be mounted and used at the same location as the steering column, sun visor, A-pillar portion, and the user does not need to hold the microphone. It is also possible to eliminate the microphone cable itself. That is, it has been found that the above-mentioned problem can be solved by integrating the microphone with the housing constituting the monitor. In this case, since no microphone cable is present, no wiring work is required. In addition, since the microphone cable is not exposed in the vehicle interior, there is no need to worry about deterioration of appearance due to the exposed wiring.

  The present invention is an in-vehicle device that has the advantages as described above, and can be controlled using voice recognition, and includes a monitor for displaying map information and other information, and a voice input device. An in-vehicle device, wherein the microphone is connected to the monitor. In the in-vehicle device according to the present invention, a voice input microphone (hereinafter simply referred to as a microphone) is connected to the monitor as a form connected to the monitor via a microphone cable, or a microphone without a cable. Is directly connected to the monitor. According to the form of connecting to the monitor via a cable, the wiring work is significantly reduced as compared with the conventional case where the wiring work is performed from the trunk room to the front part of the vehicle interior. Also, the length of the cable can be shorter than the conventional one. According to the embodiment in which the microphone is directly connected to the monitor, the wiring work itself becomes unnecessary. In addition, since the cable is not necessary, the cable is not exposed to the vehicle interior as in the conventional case, and it is possible to solve a complaint from the user that the appearance is poor. When the microphone is attached to the monitor via a cable, the position where the microphone is installed is arbitrary. In other words, the microphone can be installed in places such as the dashboard, the steering column, the sun visor, and the A-pillar as in the past. There are the following two forms for directly connecting the microphone to the monitor. In general, a monitor includes a housing for holding a display unit such as a liquid crystal display element and other parts. The monitor is attached to the outside of the housing, and the microphone is attached (built in) to the inside of the housing. is there. In either case, the microphone will be installed on the monitor.

  The number of microphones connected to the monitor is not limited to one, but may be plural. Further, the microphone can be detachable from the monitor. That is, it is also within the scope of the present invention that the microphone cable or the microphone itself is detachably connected to the monitor. When the microphone is directly connected to the monitor, the microphone can be fixed with respect to the monitor, but the direction can be changed. This is because it is desirable to set the microphone directivity axis to an optimum direction with respect to the speaker. As means for changing the direction of the microphone, a driving source such as a motor can be used in addition to manual operation by the user.

  A typical application example of the vehicle-mounted device of the present invention is a car navigation system. Therefore, in the present invention, a recognition unit for recognizing the input voice, a monitor for displaying a result recognized by the recognition unit, and a single unit connected to the monitor for inputting the sound. And a car navigation system characterized by comprising the above microphone. Moreover, although it can apply also to a car audio, if it is in-vehicle equipment, a use will not ask | require. In the vehicle interior, engine sound and other noises are input to the microphone in addition to the voice for voice recognition. In the car navigation system of the present invention, noise suppression means for suppressing noise can be provided. As the noise suppression means, known noise suppression means can be widely applied, but the characteristic noise suppression means in the present invention functions when a microphone is directly connected to a monitor. That is, the sensitivity of the microphone is improved by the diffraction effect of the entire monitor, and noise is suppressed. Therefore, in this case, the monitor constitutes noise suppression means. As a technique for suppressing noise, it has been conventionally practiced to provide a noise collecting microphone separately from a voice input microphone. In the present invention, an audio input microphone can be installed on either the front or back side of the monitor, and a noise input microphone can be installed on the other side of the monitor. That is, in the present invention, a monitor main body for displaying map information and other information, a voice input microphone installed on one of the front and back surfaces of the monitor main body, and a noise input installed on the other surface of the monitor main body And a microphone for monitoring. The noise input microphone corresponds to the noise suppression means described above, but is characterized in that it is installed on the back surface of the monitor main body on which the voice input microphone is installed. The advantages will be described in the embodiments of the invention described later.

  As described above, according to the in-vehicle device of the present invention, since the microphone is connected to the monitor, a long cable for the microphone is unnecessary, and the microphone cable wiring work is unnecessary or simple.

1 is a block diagram showing a system configuration of a car navigation system according to a first embodiment of the present invention. It is a block diagram which shows the structure of the recognition part 5 of the car navigation system concerning 1st Embodiment of this invention. It is a figure which shows the processing flow in the recognition part 5 of the car navigation system concerning 1st Embodiment of this invention. It is a front view of the monitor 6 which concerns on 1st Embodiment of this invention. It is a front view of the monitor 160 which concerns on 2nd Embodiment of this invention, Comprising: It is a figure which shows the state in which the microphone 140 was attached. It is a front view of the monitor 160 which concerns on 2nd Embodiment of this invention, Comprising: It is a figure which shows the state which removed the microphone 140. FIG. It is a figure which shows the structure of the microphone 140 which concerns on 2nd Embodiment of this invention. It is a figure which shows the other structure of the microphone 140 which concerns on 2nd Embodiment of this invention. It is a front view of the monitor 260 which concerns on 3rd Embodiment of this invention. It is a rear view of the monitor 260 which concerns on 3rd Embodiment of this invention. It is a figure which shows one example of the electrical mechanism for noise suppression. It is a front view of the monitor 360 which concerns on 4th Embodiment of this invention. It is a top view of the monitor 360 which concerns on 4th Embodiment of this invention. It is a figure for demonstrating an example of a sound source estimation means. It is a side view of the monitor 460 which concerns on 5th Embodiment of this invention. It is a front view of the monitor 460 which concerns on 5th Embodiment of this invention.

<First Embodiment>
Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings. FIG. 1 is a diagram for explaining the overall system configuration of the car navigation system according to the first embodiment. In this figure, reference numeral 1 is an arithmetic processing unit that controls the entire navigation apparatus, 2 is a positioning unit that measures its own position, 3 is a remote controller as operation means of the car navigation system, and 4 is operation information from the remote controller 3. 5 is a recognition unit for recognizing input speech, and 6 is a monitor for displaying map information and other information.

  Here, the arithmetic processing unit 1 includes a CPU 7 that controls the whole, a ROM 8 that stores predetermined programs, a RAM 9 that stores various data, the positioning unit 2, the receiving unit 4, the recognizing unit 5, and the monitor 6. Etc., and an I / O circuit unit 10 that performs input / output with the device. The positioning unit 2 performs positioning by GPS (Global Positioning System), and a 1575.42 MHz signal (radio wave) transmitted from a plurality of (usually four or more) GPS satellites at an altitude of about 20,000 km. Is received by a receiving antenna (not shown), positioning calculation is performed based on this signal, and positioning data indicating the current position is transferred to the arithmetic processing unit 1. Various operations of the car navigation system can be performed by the remote controller 3. For example, the remote controller 3 displays an operation menu on the monitor 6, changes the display range of the electronic map on the monitor 6, or moves the cursor on various operation menus displayed on the monitor 6. Can do. And the signal based on the operation information by this remote controller 3 is transmitted wirelessly, and after this is received by the receiving part 4, it is transmitted to the arithmetic processing part 1, and the operation content is performed.

  A microphone 40 for voice input is connected to the monitor 6. Various operations of the car navigation system can be controlled by the sound input from the microphone 40 as well as the remote controller 3, and the result is displayed on the monitor 6. For example, by designating the destination by voice, the map information including the destination can be displayed on the monitor 6. The voice input to the microphone 40 is recognized by the recognition unit 5. As shown in FIG. 2, the recognition unit 5 includes a CPU 51, a ROM 52 that stores a predetermined program, and a RAM 53 that stores various data. The recognition unit 5 performs recognition processing as shown in FIG. That is, the input audio signal is converted from an analog value to a digital value. An acoustic analysis is performed after noise suppression processing is performed on the converted audio signal. A known method can be applied to the noise suppression process. In acoustic analysis, a feature amount of speech is extracted. Thereafter, speech recognition is performed by comparing the extracted feature quantity with the standard pattern. The recognized result is displayed on the monitor 6. Furthermore, as shown in FIG. 1, the car navigation system includes a storage medium 11 that stores map information and other information.

  FIG. 4 shows a front view of the monitor 6. The monitor 6 includes a display unit 61 for displaying map information and the like, and a monitor housing 62 that houses the display unit 61 and the like. From the monitor housing 62 of the monitor 6, the microphone cable 41 of the microphone 40 is drawn out. In the present embodiment, the microphone cable 41 is fixed to the monitor housing 62, but may be detachable. That is, the monitor housing 62 has a built-in connector, and the microphone cable 41 can be attached to and detached from the connector. The monitor 6 is attached to a front part of a vehicle interior such as a dashboard or a console box via a column 63. Therefore, if the microphone 40 is mounted on a sun visor or dashboard as in the prior art, the length of the microphone cable 41 of about 1 to 2 m is sufficient. In addition, the position where the microphone 40 is attached is not limited, and the microphone 40 can be attached at any position in the vehicle cabin other than the sun visor and the dashboard. However, since the speaker with respect to the microphone 40 may be a driver or a person sitting in the passenger seat, it will be at any position in the front part of the passenger compartment.

  Further, according to the present embodiment, the monitor 6 is disposed in the front part of the vehicle interior as compared with the conventional case where the microphone cable is wired from the trunk room to the front part of the vehicle interior. The work is simple. In the present embodiment, conventionally known microphones 40 and microphone cables 41 can be applied. For example, as the microphone 40, there are a unidirectional microphone and an omnidirectional microphone, either of which can be used. However, the unidirectional microphone is preferable because the possibility of noise collection is reduced. Moreover, although the microphone 40 is single in this Embodiment, you may attach multiple.

Second Embodiment
A second embodiment according to the present invention will be described with reference to FIGS. Note that the basic configuration of the car navigation system according to the second embodiment is the same as that of the first embodiment, and therefore, differences will be mainly described here. As shown in FIG. 5, the monitor 160 according to the second embodiment includes a display unit 161 for displaying map information and the like, and a monitor housing 162 that houses the display unit 161 and the like. The difference between the second embodiment and the first embodiment is that the microphone 40 and the monitor housing 62 are connected via the microphone cable 41 in the first embodiment, whereas the microphone in the second embodiment is a microphone. 140 is directly connected to the monitor housing 162. The monitor housing 162 has a built-in connector for connecting to the microphone 140, and the microphone 140 is detachable from the monitor housing 162 as shown in FIG.

  According to the second embodiment described above, since the microphone 140 is directly connected to the monitor housing 162, the work of wiring the microphone cable is completely unnecessary. Further, the microphone cable is not exposed in the vehicle interior. Although some users dislike that the appearance of the microphone cable is poor when the microphone cable is exposed in the vehicle interior, the second embodiment can meet such user demands. In addition, a noise suppression effect can be expected by directly connecting the microphone 140 to the monitor 160, that is, as a single unit, as in the second embodiment. That is, the sensitivity of the microphone 140 is improved by the diffraction effect of the entire monitor 160. This improvement in sensitivity due to the diffraction effect can be experienced by placing a palm behind the ear when a human hears a small sound.

  In the second embodiment, the microphone 140 includes a microphone body 141 and a microphone casing 142 as shown in FIG. The microphone main body 141 is composed of a unidirectional microphone, and this directional characteristic is controlled in combination with the microphone casing 142 to amplify sound and suppress noise. The unidirectional microphone main body 141 can improve directivity by increasing the distance between the front acoustic terminal and the rear acoustic terminal, that is, the distance between the two acoustic terminals. FIG. 7 shows a front view (left side) and a side view (right side) of the microphone 140, and it can be seen that the microphone housing 142 has a cross section having a through hole 142h. The microphone main body 141 is disposed at an intermediate portion of the through hole 142h in the penetrating direction. The distance between the two sound terminals of the microphone main body 141 is d1, whereas the distance between the two sound terminals d2 as the microphone 140 is set to the distance between the two sound terminals of the microphone main body 141 by combining with the microphone housing 142. It can be larger than d1. The commercially available microphone main body 141 is often a simple columnar shape as shown in FIG. 7, but according to the present embodiment, the commercially available microphone main body 141 is used and the microphone main body 141 is attached to the monitor 160. In combination with the microphone housing 142, there is an advantage that the distance between the two sound terminals can be increased. In the present embodiment, the microphone casing 142 is a kamakura type, but the present invention is not limited to this. Any form is effective for the present invention as long as it has a function of attaching the microphone body 140 to the monitor 160 and a function of increasing the distance between the two sound terminals. FIG. 8 shows another configuration example of the microphone 140. The microphone 140 of FIG. 8 has basically the same configuration as the microphone 140 shown in FIG. 7, but has a through hole 142 i formed in the upper portion of the microphone casing 142. When air flows through the through-hole 142i, the microphone 140 can be prevented from becoming hot due to solar radiation or the like.

<Third Embodiment>
A third embodiment according to the present invention will be described with reference to FIGS. Note that the basic configuration of the car navigation system according to the third embodiment is the same as that of the first and second embodiments, and therefore, differences will be mainly described here. FIG. 9 is a front view of a monitor 260 according to the third embodiment, and FIG. 10 is a rear view thereof. As shown in FIG. 9, the monitor 260 according to the third embodiment includes a display unit 261 for displaying map information and the like, and a monitor housing 262 for housing the display unit 261 and the like. The third embodiment differs from the second embodiment in that the microphone 140 is attached to the outside of the monitor housing 162 in the second embodiment, whereas the microphone 240 is a monitor housing in the third embodiment. It is the point embedded in 262.

  According to the third embodiment described above, the microphone 240 is directly connected to the monitor housing 262. Therefore, similarly to the second embodiment, there is an effect that the wiring work of the microphone cable is not required at all, and the microphone cable is not exposed in the vehicle interior. In addition, since the microphone 240 is embedded in the monitor housing 262, the microphone 140 does not protrude outside the monitor 160 as in the second embodiment, and the user feels neat. Also in the third embodiment, since the microphone 240 is attached to the monitor 260 as in the second embodiment, the sensitivity of the microphone 240 can be improved by the diffraction effect of the entire monitor 260.

  In the third embodiment, as shown in FIG. 10, a noise microphone 241 for collecting noise is built in the monitor housing 262 on the back side of the monitor 260. The microphone 240 shown in FIG. 9 collects not only voice but also noise. On the other hand, the noise microphone 241 collects noise. Therefore, if the “noise signal” from the noise microphone 241 is subtracted from the “voice signal + noise signal” from the microphone 240, only the voice signal can be extracted. As described above, a technique of using only one microphone for “voice signal + noise signal” and the other microphone for “noise signal” and extracting only “voice signal” is already known. However, as in the third embodiment, the configuration in which the “sound signal + noise signal” microphone 240 and the “noise signal” noise microphone 241 are arranged on the front and back surfaces of the monitor 260 is novel.

  When the distance between the microphone 240 and the noise microphone 241 is large, the noise signal collected by the microphone 240 and the noise signal collected by the noise microphone 241 are different. Therefore, the “noise signal” is changed from “voice signal + noise signal”. The process of decreasing becomes unrealistic. Therefore, it is desirable that the microphone 240 and the noise microphone 241 are disposed at close positions. However, since the noise microphone 241 is a signal for which a noise signal is desired, it should be placed at a position where it is difficult to collect the voice of the speaker. That is, in consideration of this point, it is not desirable to arrange the microphone 240 and the noise microphone 241 at very close positions. However, if the noise microphone 241 is disposed on the back side of the monitor 260 as in the third embodiment, the sound from the speaker is blocked by the monitor 260. That is, it can be said that the noise microphone 241 is arranged at a position where it is difficult to collect the voice of the speaker. In addition, it is possible to satisfy the requirement that the noise microphone 241 should be disposed at a position close to the microphone 240. Therefore, the process of subtracting “noise signal” from “voice signal + noise signal” is effective.

  In the third embodiment, an example in which two microphones 240 and two noise microphones 241 are provided has been described. However, the present invention is not limited to this, and one or two or more microphones may be provided. Good. Further, the positions where the microphones 240 and the noise microphones 241 are arranged are also the upper ends of the monitor 260 in the third embodiment, but the present invention is not limited to this, and may be appropriately determined according to the number of the microphones 240 and noise microphones 241. it can. In addition to the above, noise suppression can also be performed by an electrical mechanism as shown in FIG. In FIG. 11, M represents a microphone, A represents an amplifier, and τ represents a delay of one sample. However, such known electrical noise suppression means can be provided.

<Fourth embodiment>
A fourth embodiment according to the present invention will be described with reference to FIGS. Since the basic configuration of the car navigation system according to the fourth embodiment is the same as that of the first to third embodiments, the differences will be mainly described here. FIG. 12 is a front view of a monitor 360 according to the fourth embodiment, and FIG. 13 is a plan view. As shown in FIG. 12, the monitor 360 according to the fourth embodiment includes a display unit 361 for displaying map information and the like, and a monitor housing 362 for housing the display unit 361 and the like. In the fourth embodiment, similarly to the second embodiment, a microphone 340 is directly connected to the monitor housing 362. In the second embodiment, the microphone 140 attached to the monitor housing 162 was detachable, but the direction could not be changed. However, in the fourth embodiment, the direction of the microphone 340 can be changed. That is, as shown in FIG. 13, the microphone 340 is attached to the monitor 360 so as to be rotatable. Therefore, the directivity axis of the microphone 340 can be directed to the speaker, that is, the sound source.

  The microphone 340 may be rotated manually or using a driving source such as a motor. When a plurality of microphones 340 are provided as in the fourth embodiment, the plurality of microphones 340 can be rotated simultaneously using a link mechanism or the like. In the fourth embodiment, the example in which the direction of the microphone 340 is changed in the horizontal direction has been described. However, the direction can be changed in the vertical direction. Moreover, the direction of the microphone 340 suitable for each speaker can be registered (preset) in advance, and when the speaker becomes a driver, the microphone 340 can be directed in the preset direction. . For example, when a car equipped with the navigation device according to the fourth embodiment is used by a family, the direction of the microphone 340 is preset for each person who drives the car in the family. When the user is driving, the preset orientation of the microphone 340 is read, and the orientation of the microphone 340 is set to that orientation.

  The preset of the direction of the microphone 340 can be realized by using sound source estimation means. FIG. 14 shows an example of the sound source estimation means, which uses the noise suppression means shown in FIG. In the noise suppression means shown in FIG. 11, τ (one sample delay) is added to each microphone M, but the directivity axis as the microphone system can be changed by increasing or decreasing the delay amount in software. That's it. For example, assume that four microphones M1 to M4 are arranged at equal intervals as shown in FIG. A sound source estimation system is provided separately from the output signal system, and the delay amount is sequentially changed therein. First, a 6-sample delay is added to the output of the microphone M1, a 4-sample delay is added to the microphone M2, and a 2-sample delay is added to the microphone M3, and no delay is added to the microphone M4. Is detected. Next, there is no delay in the output of the microphone M1, 2 sample delay is added to the microphone M2, 4 sample delay is added to the microphone M3, and 6 sample delay is added to the microphone M4. Is detected. Furthermore, the audio output level when no delay is applied to all the microphones M1 to M4 is detected. Among these three types of audio output levels, the one with the highest level is selected, and the method of delaying at that time is copied to the output signal system to perform sound source estimation processing. As for the preset of the microphone 340, any known means may be employed in addition to the sound source estimating means described above.

<Fifth Embodiment>
A fifth embodiment according to the present invention will be described with reference to FIGS. 15 and 16. The basic configuration of the navigation system according to the fifth embodiment is the same as that of the first embodiment, and the microphone 440 is connected to the monitor 460 via the microphone cable 441. As shown in FIGS. 15 and 16, the monitor 460 according to the fifth embodiment includes a display unit 461 for displaying map information and the like, and a monitor housing 462 for housing the display unit 461 and the like. The monitor 460 is attached to an arbitrary position in the front part of the vehicle interior via the column 470. Generally, it is attached to the center of the dashboard in the vehicle width direction. An L-shaped and hollow arm 480 for fixing the microphone 440 is extended from the column 470. A microphone 440 is attached to the tip of the arm 480. The microphone 440 is disposed close to the surface of the monitor 460. The microphone 440 is connected to the monitor 460 via the microphone cable 441. The microphone cable 441 is pulled out from the back surface of the monitor 460, wired in the hollow portion of the arm 480, and connected to the microphone 440.

  When the microphone 140 (240, 340) is directly connected to the monitor 160 (260, 360) as in the second (third, fourth) embodiment, the diffraction effect of the entire monitor 160 (260, 360) is caused. The sensitivity of the microphone 140 (240, 340) could be improved. In the case of the fifth embodiment, the microphone 440 is connected to the monitor 460 via the microphone cable 441, but the microphone 440 is disposed close to the surface of the monitor 460 using the arm 480. Therefore, the sensitivity of the microphone 440 can be improved by the diffraction effect of the entire monitor 460.

DESCRIPTION OF SYMBOLS 1 ... Arithmetic processing part, 3 ... Remote controller, 5 ... Recognition part, 6,160,260,360,460 ... Monitor, 11 ... Storage medium, 40,140,240,340,440 ... Microphone, 41,441 ... Microphone Cable, 61, 161, 261, 361, 461 ... display unit, 62, 162, 262, 362, 462 ... monitor housing

Claims (8)

A plurality of microphones for voice input; and an audio signal generation unit that adds a delay to each of output signals from the plurality of microphones and generates an audio signal obtained by adding the signals to which the delay has been added. A microphone system in which the directivity axis is changed by changing the amount of delay applied to the output signal;
Based on the output level of the sample audio signal obtained by adding the signal obtained by adding the sample delay to the output signal from the plurality of microphones, one of the combinations of the delay amounts to be added to each of the output signals is A delay amount selection section for selecting a combination of delay amounts;
A recognition unit for recognizing the audio signal generated using the combination of delay amounts selected by the delay amount selection unit;
A control unit for controlling the operation of the apparatus based on the recognition result of the recognition unit;
A navigation device comprising:   The navigation device according to claim 1, wherein the delay amount selection unit selects the combination of the delay amounts having the highest output level. A storage unit for storing a combination of delay amounts determined by the delay amount determination unit in association with a speaker as the sound source;
Further comprising
The navigation device according to claim 1, wherein the voice signal generation unit generates the voice signal using a combination of delay amounts stored in the storage unit in association with a designated speaker.   4. The delay amount selection unit according to claim 1, wherein the delay amount selection unit detects the output level for a plurality of combinations of the delay amounts, and selects the combination of the delay amounts that maximizes the output level. 5. Navigation device. Output signals from the plurality of microphones are respectively input to the sound source estimation system having the delay amount selection unit and the output signal system having the audio signal generation unit, the recognition unit, and the control unit.
2. The navigation device according to claim 1, wherein the delay amount selection unit performs the delay amount combination selection process during a period in which the control unit performs control based on the recognition result in the output signal system.   The navigation device according to claim 1, wherein the plurality of microphones are arranged at equal intervals. Acquiring sound with a plurality of microphones;
Adding a sample delay to each of output signals from the plurality of microphones;
Generating a sample audio signal obtained by adding the signal to which the sample delay has been added;
Detecting an output level of the sample audio signal;
Selecting a combination of delay amounts to be added to each of the output signals based on the output level;
Adding a delay to each of the output signals from the plurality of microphones based on the selected combination of the delay amounts;
Generating an audio signal by adding the respective signals to which the delay has been added; and
Recognizing the audio signal;
Controlling the operation of the device based on the recognition result;
A speech recognition method. Computer
A plurality of microphones for voice input; and an audio signal generation unit that adds a delay to each of output signals from the plurality of microphones and generates an audio signal obtained by adding the signals to which the delay has been added. A microphone system in which the directivity axis is changed by changing the amount of delay applied to the output signal;
Based on the output level of the sample audio signal obtained by adding the signal obtained by adding the sample delay to the output signal from the plurality of microphones, one of the combinations of the delay amounts to be added to each of the output signals is A delay amount selection section for selecting a combination of delay amounts;
A recognition unit for recognizing the audio signal generated using the combination of delay amounts selected by the delay amount selection unit;
A control unit for controlling the operation of the apparatus based on the recognition result of the recognition unit;
A program for functioning as a navigation device.

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