CN101543091B - Voice input device, method of manufacturing the same, and information processing system - Google Patents

Abstract

The invention provides a voice input device, a method of manufacturing the same, and an information processing system. The voice input device includes: a first microphone (710-1) having a first diaphragm; a second microphone (710-2) having a second diaphragm; and a differential signal generation unit (720) that generates a differential signal of the first voltage signal and the second voltage signal; the first and second diaphragms are arranged so that a noise intensity ratio is smaller than an input voice intensity ratio indicating a ratio of an intensity of an input voice component, and a differential signal generating unit (720) includes: a delay unit (730); and a differential signal output unit (740) that generates and outputs a differential signal of the signal to which the delay is given by the delay unit.

Description

Speech input device and manufacture method thereof, information processing system

Technical field

The present invention relates to speech input device and manufacture method thereof, and information processing system.

Background technology

When conversing by telephone set etc. or carrying out speech recognition, voice recording etc., preferably only receive purpose voice (user's voice).But, in the environment for use of speech input device, have sometimes the voice except the purpose voice such as background noise.Therefore, researching and developing the speech input device with noise removal function.

As remove the technology of noise in having the environment for use of noise, known method has the method that makes microphone have sensitive directive property, perhaps utilize the poor arrival direction of identifying sound wave of due in of sound wave, and process the method that removes noise by signal.

In addition, in recent years, electronic equipment is miniaturization increasingly, realizes that the technology of the miniaturization of speech input device becomes important.As the prior art in this field, the flat 7-312638 communique of TOHKEMY, the flat 9-331377 communique of TOHKEMY, TOHKEMY 2001-186241 communique are arranged.

Summary of the invention

Make microphone have sensitive directive property, need to arrange a plurality of vibrating membranes, so be difficult to realize miniaturization.

In addition, utilize the poor arrival direction that detects accurately sound wave of due in of sound wave, the interval of 1 left and right that need to divide with several wavelength of audible sound arranges a plurality of vibrating membranes, therefore is difficult to realize miniaturization.

In addition, if utilize the differential signal of the obtained sound wave of a plurality of microphones, the delay that produces in the manufacture process of microphone or the deviation of gain exert an influence to the noise removal precision sometimes.

The purpose of a plurality of execution modes of the present invention is, a kind of speech input device and manufacture method and information processing system that the noise composition is removed function that have is provided.

(1) the present invention is a kind of speech input device, and it comprises:

The first microphone, it has the first vibrating membrane,

Second microphone, it has the second vibrating membrane,

The differential signal generating unit, the first voltage signal that it is obtained according to described the first microphone and the obtained second voltage signal of described second microphone, the differential signal of generation the first voltage signal and second voltage signal;

This speech input device is characterised in that,

The described first and second vibrating membrane is configured to noise intensity than the structure that is less than input voice strength ratio, wherein, described noise intensity than the intensity that means to be included in the noise composition in described differential signal with respect to be included in described first or the second voltage signal in the ratio of intensity of described noise composition, the intensity that described input voice strength ratio means to be included in the input phonetic element in described differential signal with respect to be included in described first or the second voltage signal in the ratio of intensity of described input phonetic element

Described differential signal generating unit comprises delay section and differential signal efferent,

Described delay section gives after regulation postpones at least one signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, and the signal after regulation postpones has been given in output,

Described differential signal efferent receives have been given by described delay section the signal that postpones and has been used as at least one signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, generates and export the differential signal of the first voltage signal and second voltage signal.

At this, can arrange to the first obtained voltage signal of the first microphone give regulation postpone after output the first delay section, to the second voltage signal give regulation postpone after at least one party in the second delay section of output, at least one party's voltage signal is postponed, thereby generate differential signal.In addition, the first delay section and the second delay both sides of section can be set also, the both sides of the first voltage signal and second voltage signal are all postponed, thereby generate differential signal.When the first delay section and the second delay both sides of section are set, can constitute the delay section that any one party is given fixed delay, and constitute the variable delay section of the delay that can adjust changeably the opposing party.

Due to the electric or mechanical structure in manufacturing process, the delay of the microphone deviation that mostly occurs.Confirm by experiment, when having the deviation of this delay, can affect noise suppression effect.

If employing the present invention gives regulation at least one party in the first voltage signal and second voltage signal and postpones, can proofread and correct thus the delay distortion of the first voltage signal and second voltage signal, therefore can prevent from reducing noise suppression effect because of delay distortion.

According to this speech input device, first and second microphone (the first and second vibrating membrane) be configured to satisfy defined terms.Thus, the differential signal of the difference of expression first and obtained first and the second voltage signal of second microphone can be considered as that the noise composition is removed, the signal of expression input voice.Therefore, according to the present invention, only can provide and just can realize the speech input device of noise removal function by the simple structure that generates differential signal.

In addition, in this speech input device, the differential signal generating unit need not to first and the second voltage signal carry out dissection process (Fourier dissection process etc.), just can generate differential signal.Therefore, can alleviate the signal processing load of differential signal generating unit, perhaps, can realize the differential signal generating unit by very simple circuit.

Thus, according to the present invention, can provide the speech input device that to realize miniaturization and can realize high-precision noise removal function.

In addition, in this speech input device, the first and second vibrating membrane can be configured to: the strength ratio of the phase difference composition of noise composition is less than the strength ratio based on the amplitude of inputting phonetic element.

(2) speech input device of the present invention is characterised in that,

Described differential signal generating unit comprises:

Delay section, it makes retardation change according to the electric current that flows through on the terminal of regulation,

Postpone control part, its terminal feeding to described regulation is used for controlling the electric current of the retardation of described delay section;

Described delay control part comprises the electric resistance array that a plurality of resistance are arranged connected in series or in parallel, and cut off the resistive element of the described electric resistance array of formation or the part of conductor, perhaps, comprise at least one resistive element and cut off the part of this resistive element, thus, can change electric current to the terminal feeding of the regulation of delay section.

Can shear the resistive element of formation electric resistance array or the part of conductor by laser, perhaps, by applying high voltage or high electric current the fuse resistive element that consists of electric resistance array or the part of conductor, change thus resistance value, also can change resistance value by form cut channel on the part of a resistive element.

The deviation of the delay that inspection is caused by the individual difference that produces in the manufacture process of microphone, and determine the retardation of the first voltage signal, poor to eliminate the delay that is produced by this deviation.And, the resistive element of the described electric resistance array of cut-out formation or conductor are (for example, fuse) a part, make it possible to voltage or the electric current of the terminal feeding of stipulating for the retardation that realizes determining, perhaps, form cut channel on the part of resistive element, thereby the resistance value that will postpone control part is set as suitable value.Thus, can adjust delay balance with the obtained second voltage signal of described second microphone.

(3) speech input device of the present invention is characterised in that,

Described differential signal generating unit comprises:

Phase difference detection section, its reception is input to the first voltage signal and the second voltage signal of described differential signal efferent, according to the first voltage signal that receives and second voltage signal, the first voltage signal when detecting the generation differential signal and the phase difference of second voltage signal, generate and the output phase difference signal according to testing result, and

Postpone control part, it is according to described phase signal, the control that the retardation in described delay section is changed.

For example, can come the comparison phase place by analog multiplier, realize thus phase difference detection.

Phase difference detection section for example can generate described phase signal (represent leading or lag behind by signal polarity), be in which state of lag or lead according to the relative the opposing party of phase place of at least one party in the first voltage signal and second voltage signal, the polarity of this phase signal changes, and this phase signal pulse duration changes according to phase pushing figure.

According to the present invention, can detect in real time and adjust in use the deviation of the delay that changes because of a variety of causes.

(4) speech input device of the present invention is characterised in that,

Described phase difference detection section comprises:

The one 2 value section, its level with regulation carries out 2 values to received described the first voltage signal to be processed, and converts received described the first voltage signal to first digital signal;

The 22 value section, its level with regulation carries out 2 values to received described second voltage signal to be processed, and converts received described second voltage signal to second digital signal; And

The phase signal efferent, it calculates the phase difference of described the first digital signal and described the second digital signal, and the output phase difference signal.

(5) speech input device of the present invention is characterised in that,

Comprise sound source section, this sound source section is arranged on from described the first microphone and described second microphone equidistant position,

Described differential signal generating unit comprises phase difference detection section and delay control part,

Described phase difference detection section receives the first voltage signal and the second voltage signal that is input to described differential signal efferent, according to the first voltage signal that receives and second voltage signal, the first voltage signal when detecting the generation differential signal and the phase difference of second voltage signal, generate and the output phase difference signal according to testing result

Described delay control part is according to described phase signal, the control that the retardation in described delay section is changed,

Described differential signal generating unit is according to the sound from described sound source section, the control that the retardation in described delay section is changed.

(6) speech input device of the present invention comprises:

The first microphone, it has the first vibrating membrane,

Second microphone, it has the second vibrating membrane,

The differential signal generating unit, the first voltage signal that it is obtained according to described the first microphone and the obtained second voltage signal of described second microphone, the differential signal of generation the first voltage signal and second voltage signal;

This speech input device is characterised in that,

Comprise:

Delay section, it is given after regulation postpones at least one signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, and the signal after regulation postpones has been given in output,

The differential signal efferent, it receives by described delay section and has given the signal that postpones, be used as at least one signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, generate the differential signal of the first voltage signal and second voltage signal

Sound source section, it is arranged on from described the first microphone and described second microphone equidistant position;

Described differential signal generating unit is according to the sound from described sound source section, the control that the retardation in described delay section is changed.

(7) speech input device of the present invention is characterised in that,

Described differential signal generating unit comprises:

Phase difference detection section, its reception is input to the first voltage signal and the second voltage signal of described differential signal efferent, according to the first voltage signal that receives and second voltage signal, the first voltage signal when detecting the generation differential signal and the phase difference of second voltage signal, generate and the output phase difference signal according to testing result, and

Postpone control part, it is according to described phase signal, the control that the retardation in described delay section is changed.

(8) speech input device of the present invention is characterised in that, described sound source section is the sound source of sending the sound of single-frequency.

(9) speech input device of the present invention is characterised in that, is the outer frequency of audio-band with the frequency setting of described sound source section.

If be the outer frequency of audio-band with the frequency setting of described sound source section, can be in the situation that the user can obstacles when using yet, utilize sound source section to adjust the phase difference of input signal or postpone poor.According to the present invention, can dynamically adjust in use delay, therefore can adjust delay according to environment around variations in temperature etc.

(10) speech input device of the present invention is characterised in that,

Described phase difference detection section comprises the first band pass filter, the second band pass filter,

The first received voltage signal is input to described the first band pass filter, and described the first band pass filter passes through described single-frequency,

Received second voltage signal is input to described the second band pass filter, and described the second band pass filter passes through described single-frequency,

Described phase difference detection section comes detected phase poor according to by the first voltage signal after the first band pass filter with by the second voltage signal after the second band pass filter.

Can send in sound source section the sound of single-frequency, and after removing sound beyond it by the first band pass filter and the second band pass filter, detected phase is poor, therefore poor the or retardation of detected phase accurately.

In addition, in the situation that speech input device itself does not have sound source section, also can when test will test be arranged on sound source temporarily speech input device near, to test to be set as with sound source makes sound input to the first microphone and second microphone with same phase, receive sound by the first microphone and second microphone, and the waveform of the first voltage signal of exporting and second voltage signal is monitored and is changed the retardation of delay section, make both phase places consistent.In addition, phase difference detection section and band pass filter might not be arranged in speech input device, also can similarly be arranged on the outside with measuring sound source.

(11) speech input device of the present invention is characterised in that, comprising:

Noise measuring delay section, after it gave to the obtained second voltage signal of described second microphone the delay that noise measuring uses, the signal after the delay that noise measuring uses had been given in output,

Noise measuring differential signal generating unit, its generted noise detects the differential signal of use, the differential signal that this noise measuring is used represents to have given the poor of second voltage signal that regulation that noise measuring uses postpones and obtained the first voltage signal of described the first microphone by described noise measuring with delay section

Noise measuring section, its differential signal of using according to described noise measuring judges the level of noise, and according to judged result output noise detection signal, and

The signal switching part, it receives differential signal and the first obtained voltage signal of described the first microphone that described differential signal generating unit is exported, switches output the first voltage signal and described differential signal according to described noise detecting signal.

According to the present invention, can detect by the directional property of the controlling differential microphone noise state around resulting except speaker's voice of making a return journey, and according to the level of the noise that detects, can switch the output of single microphone and the output of differential microphone.Therefore, when detect around noise less than the regulation level the time, switch to the output of single microphone, when greater than the regulation level the time, switch to the output of differential microphone, can be provided at thus under quiet environment preferential SN than and under high noise environments the preferential speech input device that suppresses distant place noise.

(12) the present invention is a kind of speech input device, it is characterized in that, comprising:

The first microphone, it has the first vibrating membrane,

Second microphone, it has the second vibrating membrane,

The differential signal generating unit, the first voltage signal that it is obtained according to described the first microphone and the obtained second voltage signal of described second microphone, the differential signal of generation the first voltage signal and second voltage signal,

Noise measuring delay section, after it gave to the obtained second voltage signal of described second microphone the delay that noise measuring uses, the signal after the delay that noise measuring uses had been given in output,

Noise measuring differential signal generating unit, its generted noise detects the differential signal of use, the differential signal that this noise measuring is used represents to have given the poor of second voltage signal that regulation that noise measuring uses postpones and obtained the first voltage signal of described the first microphone by described noise measuring with delay section

Noise measuring section, its differential signal of using according to described noise measuring judges the level of noise, and according to judged result output noise detection signal, and

The signal switching part, it receives differential signal and the first obtained voltage signal of described the first microphone that described differential signal generating unit is exported, and switches output the first voltage signal and described differential signal according to described noise detecting signal.

(13) speech input device of the present invention is characterised in that, also comprises:

Loud speaker, its output sound information; And

Volume control section, it controls the volume of described loud speaker according to described noise detecting signal.

During greater than the level of regulation, speaker volume can be improved when the level of described noise, during less than the level of regulation, speaker volume can be reduced when the level of described noise.

(14) speech input device of the present invention is characterised in that,

The delay that described noise measuring is used be set as distance between centers with the first vibrating membrane and the second vibrating membrane divided by velocity of sound after time of gained.

So set retardation, the directional property of speech input device is set as heart, and with speaker's set positions near directive property invalid position, obtain thus blocking speaker's voice and the directive property of easily only picking up ambient noise, therefore can be used in noise measuring.

(15) speech input device of the present invention is characterised in that,

Also comprise:

The one AD converting unit, it carries out analog/digital conversion to described the first voltage signal,

The 2nd AD converting unit, it carries out analog/digital conversion to described second voltage signal,

Described differential signal generating unit basis converts described first voltage signal of digital signal to by a described AD converting unit and converts the described second voltage signal of digital signal by described the 2nd AD converting unit to, generates the differential signal of the second voltage signal of the first voltage signal.

(16) speech input device of the present invention is characterised in that, the delay of described delay section is set as the integral multiple of the change-over period of analog/digital conversion.

(17) speech input device of the present invention is characterised in that, the distance between centers of the first vibrating membrane and the second vibrating membrane is set to value or its integral multiple that be multiply by gained after velocity of sound the change-over period of analog/digital conversion.

Like this, with in delay section, in the mode of numeral postpone the simple action of n (n as integer) clock by making input voltage signal in noise measuring, can be simply and realize accurately being suitable for picking up around the directional property of heart of noise.

(18) speech input device of the present invention is characterised in that,

Also comprise gain section, after this gain section gave the regulation gain at least one signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, the signal after the regulation gain had been given in output,

Described differential signal efferent receives by described gain section and has given the signal of gain at least one signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, generates and export the differential signal of the first voltage signal and second voltage signal.

According to the present invention, give the regulation gain at least one party in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, the caused gain deviation of individual difference in the time of can absorbing thus the manufacturing by two microphones.At this, can proofread and correct, so that the amplitude of the first voltage signal of relative regulation input acoustic pressure and second voltage signal is identical or difference of vibration the first voltage signal and second voltage signal is restrained within the limits prescribed.Thus, can prevent from reducing noise suppression effect because of the caused sensitivity deviation of individual difference of the microphone that produces in manufacturing process.

(19) speech input device of the present invention is characterised in that,

Also comprise base portion, be formed with recess on the interarea of this base portion,

Described the first vibrating membrane is arranged on the bottom surface of described recess,

Described the second vibrating membrane is arranged on described interarea.

(20) speech input device of the present invention is characterised in that, described base portion is configured to: the opening that is communicated with described recess is configured in the position than the model sound source of the more close described input voice in formation zone of described the second vibrating membrane on described interarea.

According to this speech input device, can reduce to incide the phase deviation of the input voice of the first and second vibrating membrane.Therefore, can the few differential signal of generted noise, thus the speech input device with high-precision noise removal function can be provided.

(21) speech input device of the present invention is characterised in that, described recess is more shallow than the interval between the formation zone of described opening and described the second vibrating membrane.

(22) speech input device of the present invention is characterised in that,

Also comprise base portion, be formed with the first recess and second recess more shallow than described the first recess on the interarea of this base portion,

Described the first vibrating membrane is arranged on the bottom surface of described the first recess,

Described the second vibrating membrane is arranged on the bottom surface of described the second recess.

(23) speech input device of the present invention is characterised in that, described base portion is configured to: the first opening that is communicated with described the first recess is configured in the position than the model sound source of the more close described input voice of the second opening, and this second opening is communicated with described the second recess.

According to this speech input device, can reduce to incide the phase deviation of the input voice of the first and second vibrating membrane.Therefore, can the few differential signal of generted noise, thus the speech input device with high-precision noise removal function can be provided.

(24) speech input device of the present invention is characterised in that, the difference of the degree of depth of described the first recess and the second recess is less than the interval between described the first opening and the second opening.

(25) speech input device of the present invention is characterised in that, described base portion is configured to make described input voice to arrive simultaneously the first vibrating membrane and the second vibrating membrane.

Thus, the differential signal that does not comprise the phase deviation of inputting voice can be generated, therefore the speech input device with high-precision noise removal function can be provided.

(26) the present invention is a kind of speech input device, it is characterized in that,

Comprise:

The first microphone, it has the first vibrating membrane,

Second microphone, it has the second vibrating membrane,

The differential signal generating unit, it be used for to generate differential signal, and this differential signal represents the poor of the first voltage signal that described the first microphone is obtained and the obtained second voltage signal of described second microphone;

The described first and second vibrating membrane is configured to noise intensity than the structure that is less than input voice strength ratio, wherein, described noise intensity than the intensity that means to be included in the noise composition in described differential signal with respect to be included in described first or the second voltage signal in the ratio of intensity of described noise composition, the intensity that described input voice strength ratio means to be included in the input phonetic element in described differential signal with respect to be included in described first or the second voltage signal in the ratio of intensity of described input phonetic element

At least one vibrating membrane in described the first vibrating membrane and described the second vibrating membrane is obtained sound wave by the sound guide tube of tubular, and wherein, described sound guide tube is configured to vertical with face.

Be close to sound guide tube is set with the substrate around vibrating membrane, arrive vibrating membrane so that the sound wave that receives from peristome does not leak ground to the outside, arrive vibrating membrane so enter the sound of sound guide tube unattenuatedly.According to the present invention, at least one party in described the first vibrating membrane and described the second vibrating membrane arranges sound guide tube, can change thus sound and not spatter because of diffusion the distance that arrives till vibrating membrane with declining.Therefore, set the sound guide tube of suitable length (for example, several millimeters) according to the deviation that postpones balance, can eliminate delay thus.

(27) speech input device of the present invention is characterised in that, sound guide tube is configured to make described input voice to arrive simultaneously the first vibrating membrane and the second vibrating membrane.

(28) speech input device of the present invention is characterised in that, the normal that the described first and second vibrating membrane is configured to both is parallel to each other.

(29) speech input device of the present invention is characterised in that, the described first and second vibrating membrane is configured to both normals not on same straight line.

(30) speech input device of the present invention is characterised in that, described first and second microphone be constituted as semiconductor device.

For example, first and second microphone can be silicon microphone (Si microphone).In addition, first and second microphone can be formed on a Semiconductor substrate.At this moment, first and second microphone and differential signal generating unit can be formed on a Semiconductor substrate.First and second microphone can constitute the so-called microelectromechanical systems (MEMS:MicroElectro Mechanical Systems) of utilizing semiconducter process to make.

(31) speech input device of the present invention is characterised in that, the distance between centers of described the first vibrating membrane and the second vibrating membrane is below 5.2mm.

In addition, the first and second vibrating membrane normal that can be configured to both be parallel to each other and both normal between be spaced apart below 5.2mm.

(32) the present invention is a kind of information processing system, it is characterized in that, comprising:

According to the speech input device described in above-mentioned arbitrary technical scheme; And

Dissection process section, it carries out dissection process according to described differential signal to the voice messaging that inputs in described speech input device.

If adopt this information processing system, the differential signal obtained according to speech input device, carry out dissection process to voice messaging, and wherein, in described speech input device, the first and second vibrating membrane is configured to satisfy defined terms.According to this speech input device, differential signal means the signal of the removed phonetic element of noise composition, therefore by this differential signal is carried out dissection process, can carry out various information processings based on the input voice.

Information processing system of the present invention can be the system that carries out voice recognition processing, voice authentication processing or voice-based order generation processing etc.

(33) the present invention is a kind of information processing system, it is characterized in that,

Comprise:

According to the speech input device described in above-mentioned arbitrary technical scheme,

Master computer, it carries out dissection process according to described differential signal to the voice messaging that inputs in described speech input device;

By described communication process section, communicate processing via network and described master computer.

If adopt this information processing system, the differential signal obtained according to speech input device, carry out dissection process to voice messaging, and wherein, in described speech input device, the first and second vibrating membrane is configured to satisfy defined terms.According to this speech input device, differential signal means the signal of the removed phonetic element of noise composition, therefore by this differential signal is carried out dissection process, can carry out various information processings based on the input voice.

Information processing system of the present invention can be the system that carries out voice recognition processing, voice authentication processing or voice-based order generation processing etc.

(34) the present invention is a kind of manufacture method of speech input device, and for the manufacture of the speech input device with function of removing the noise composition, this speech input device comprises:

The first microphone, it has the first vibrating membrane,

Second microphone, it has the second vibrating membrane,

The differential signal generating unit, it be used for to generate differential signal, and this differential signal represents the poor of the first voltage signal that described the first microphone is obtained and the obtained second voltage signal of described second microphone;

The manufacture method of this speech input device is characterised in that, comprising:

Prepare the step for the data of the corresponding relation between expression Δ r/ λ value and noise intensity ratio, wherein, described Δ r/ λ value represents the ratio of the wavelength X of the distance between centers Δ r of described the first vibrating membrane and the second vibrating membrane and noise, described noise intensity is included in the described noise composition in described differential signal than expression intensity with respect to be included in described first or the second voltage signal in the ratio of intensity of described noise composition

According to described data, set the step of described Δ r/ λ value,

According to the described Δ r/ λ value that sets and the wavelength of described noise, set the step of described distance between centers,

Postpone to set step, in this postpones to set step, make the delay control part comprise the electric resistance array that a plurality of resistance are arranged connected in series or in parallel, wherein, described delay control part is used for controlling the electric current of the retardation of described delay section to the terminal feeding of the regulation of delay section, the retardation of described delay section changes according to the electric current that flows through on the terminal of described regulation, and, described delay control part is for the electric current to the terminal feeding regulation of the regulation of delay section, cuts off the resistive element that consists of described electric resistance array or the part of conductor.

(35) manufacture method of speech input device of the present invention is characterised in that,

Set in step in described delay,

From described the first microphone and described second microphone equidistant position, sound source is being set,

According to the sound from described sound source section, judge the phase difference of the voltage signal that the first microphone and described second microphone are obtained, and cut off the resistive element of the described electric resistance array of formation or the part of conductor, thereby realize making this phase difference resistance value within the limits prescribed.

Description of drawings

Fig. 1 is the key diagram of speech input device.

Fig. 2 is the key diagram of speech input device.

Fig. 3 is the key diagram of speech input device.

Fig. 4 is the key diagram of speech input device.

Fig. 5 is the key diagram of making the method for speech input device.

Fig. 6 is the key diagram of making the method for speech input device.

Fig. 7 is the key diagram of speech input device.

Fig. 8 is the key diagram of speech input device.

Fig. 9 shows the figure of mobile phone as an example of speech input device.

Figure 10 shows the figure of microphone as an example of speech input device.

Figure 11 shows the figure of remote controller as an example of speech input device.

Figure 12 is the skeleton diagram of information processing system.

Figure 13 is the schematic diagram of an example of the structure of speech input device.

Figure 14 is the schematic diagram of an example of the structure of speech input device.

Figure 15 is the schematic diagram of an example of delay section and the concrete structure that postpones control part.

Figure 16 A is an example of structure of controlling statically the retardation of group delay filter.

Figure 16 B is an example of structure of controlling statically the retardation of group delay filter.

Figure 17 is the schematic diagram of an example of the structure of speech input device.

Figure 18 is the schematic diagram of an example of the structure of speech input device.

Figure 19 is the sequential chart of phase difference detection section.

Figure 20 is the schematic diagram of an example of the structure of speech input device.

Figure 21 is the schematic diagram of an example of the structure of speech input device.

Figure 22 A is the key diagram of the directive property of differential microphone.

Figure 22 B is the key diagram of the directive property of differential microphone.

Figure 23 is the schematic diagram of an example of structure with speech input device of noise detection unit.

Figure 24 means that the signal that is undertaken by noise measuring switches the flow chart of the example of action.

Figure 25 carries out the flow chart of the action case that the volume of loud speaker controls by noise measuring.

Figure 26 is the schematic diagram of an example of structure with speech input device of AD converting unit.

Figure 27 is the schematic diagram of an example of structure with speech input device of gain adjusting unit.

Figure 28 is the schematic diagram of an example of the structure of speech input device.

Figure 29 is the schematic diagram of an example of the structure of speech input device.

Figure 30 is the schematic diagram of an example of the structure of speech input device.

Figure 31 is the schematic diagram of an example of the structure of speech input device.

Figure 32 is the schematic diagram of an example of the concrete structure of gain section and control portion of gain.

Figure 33 A is an example of the structure of the magnification ratio of ride gain section statically.

Figure 33 B is an example of the structure of the magnification ratio of ride gain section statically.

Figure 34 is the schematic diagram of an example of the structure of speech input device.

Figure 35 is the schematic diagram of an example of the structure of speech input device.

Figure 36 is the schematic diagram of an example of the structure of speech input device.

Figure 37 is the schematic diagram of an example of the structure of speech input device.

Figure 38 is the schematic diagram of an example of structure with speech input device of AD converting unit.

Figure 39 is the schematic diagram of an example of the structure of speech input device.

Figure 40 comes the schematic diagram of the example of adjusting resistance value by laser trimming (laser trimming).

Embodiment

Below, describe using embodiments of the present invention with reference to accompanying drawing.But the present invention is not limited to following execution mode.In addition, the present invention includes the independent assortment of following content.

1. the structure of the speech input device of the first execution mode

At first, with reference to Fig. 1～Fig. 3, the structure of the speech input device 1 of using embodiments of the present invention is described.In addition, below illustrated speech input device 1 be the speech input device of closely saying formula, such as being applied to the voice communication apparatus such as mobile phone and transceiver (transceiver) or having utilized the information processing system (remote controller of voice authentication system, speech recognition system, order generation system, e-dictionary, translating machine, phonetic entry mode etc.) of the technology that the voice of inputting are resolved, perhaps can be applied to sound pick-up outfit, amplification system (loudspeaker), microphone system etc.

The speech input device of present embodiment comprises the first microphone 10 with first vibrating membrane 12 and the second microphone 20 with second vibrating membrane 22.At this, microphone refers to acoustic signal is transformed to the electroacoustic transducing device of the signal of telecommunication.First and second microphone 10,20 can be respectively also that vibration with the first and second vibrating membrane 12,22 (oscillating plates) is output as the converter of voltage signal.

In the speech input device of present embodiment, the first microphone 10 generates the first voltage signal.In addition, second microphone 20 generates the second voltage signal.That is, can be respectively with first and the voltage signal that generates of second microphone 10,20 be called first and the second voltage signal.

About first and second microphone 10, there is no particular limitation for 20 mechanism.In Fig. 2, as applicable to first and an example of second microphone 10,20 microphone, show the structure of Electret Condencer Microphone 100.Electret Condencer Microphone 100 has vibrating membrane 102.Vibrating membrane 102 is to receive the just film (film) of vibration of sound wave, has conductivity, and forms an end of electrode.Electret Condencer Microphone 100 also has electrode 104.It is relative with vibrating membrane 102 that electrode 104 is configured to.Thus, vibrating membrane 102 and electrode 104 form electric capacity.When sound wave incided in Electret Condencer Microphone 100, vibrating membrane 102 vibrated so that the interval between vibrating membrane 102 and electrode 104 changes, thereby the electrostatic capacitance between vibrating membrane 102 and electrode 104 is changed.For example be output as change in voltage by the variation with this electrostatic capacitance, the sound wave to Electret Condencer Microphone 100 incidents can be transformed to the signal of telecommunication.In addition, in Electret Condencer Microphone 100, electrode 104 also can have the structure that not affected by sound wave.For example, electrode 104 also can have netted (mesh) structure.

But, be not limited to Electret Condencer Microphone applicable to microphone of the present invention, and can use known any microphone.For example, as first and second microphone 10,20, also can use the microphones such as dynamic type (dynamic formula), electromagnetic type (magnetic formula), piezoelectric type (crystal formula).

First and second microphone 10,20 can be also to consist of the first and second vibrating membrane 12,22 silicon microphone (Si microphone) by silicon.By utilizing silicon microphone, can realize first and second microphone 10,20 miniaturization and high performance.At this moment, first and second microphone 10,20 can constitute an integrated circuit (IC) apparatus.That is, first and second microphone 10,20 can be formed on a Semiconductor substrate.At this moment, also differential signal generating unit 30 described later can be formed on same Semiconductor substrate.That is, first and second microphone 10,20 can constitute so-called microelectromechanical systems (MEMS:Micro Electro Mechanical Systems).Wherein, also the first microphone 10 and second microphone 20 can be constituted separately independently silicon microphone.

In the speech input device of present embodiment, as described later, utilize the differential signal of the difference of expression first and second voltage signal, realize noise composition removal function.In order to realize this function, make first and the configuration of second microphone (the first and second vibrating membrane 12,22) meet some requirements.About the first and second vibrating membrane 12,22 conditions that should satisfy, to narrate in the back its details, but in the present embodiment, the first and second vibrating membrane 12,22 (first and second microphone 10,20) is configured to noise intensity than less than input voice strength ratio.Thus, differential signal can be considered as representing the signal of the removed phonetic element of noise composition.It is below 5.2mm that the first and second vibrating membrane 12,22 for example also can be configured to distance between centers.

In addition, in the speech input device of present embodiment, and be not particularly limited the first and second vibrating membrane 12,22 towards.The first and second vibrating membrane 12,22 can be configured to both normal parallels.At this moment, the first and second vibrating membrane 12,22 can be configured to both normal not on same straight line.For example, the first and second vibrating membrane 12,22 can pull open arranged spaced on the surface of not shown base portion (for example, circuit substrate).Perhaps, the first and second vibrating membrane 12,22 also can be configured to mutual dislocation on normal direction.Yet it is not parallel that the first and second vibrating membrane 12,22 also can be configured to both normal.The normal that the first and second vibrating membrane 12,22 also can be configured to both is vertical.

And the speech input device of present embodiment has differential signal generating unit 30.Differential signal generating unit 30 generates differential signals, and described differential signal represents poor (voltage difference) of the first voltage signal that the first microphone 10 is obtained and the obtained second voltage signal of second microphone 20.In differential signal generating unit 30, need not to first and the second voltage signal carry out such as dissection process such as Fourier parsings, just can carry out the processing be used to the differential signal that is created on time zone both differences of expression.The function of differential signal generating unit 30 can realize by special-purpose hardware circuit (differential signal generative circuit), also can process to realize by the signal of CPU etc.

The speech input device of present embodiment can also comprise gain section, and this gain section is used for amplifying (mean and comprise the situation that improves gain and the situation that reduces gain) differential signal.Can realize differential signal generating unit 30 and gain section by a control circuit.But the speech input device of present embodiment also can form the structure that does not have gain section in inside.

Fig. 3 shows an example of the circuit that can realize differential signal generating unit 30 and gain section.If adopt circuit shown in Figure 3, after reception first and second voltage signal, output will have been amplified the signal of 10 times for its poor differential signal of expression.But, be used for realizing that the circuit structure of differential signal generating unit 30 and gain section is not limited thereto.

The speech input device of present embodiment can also comprise framework 40.At this moment, the profile of speech input device can be made of framework 40.Can set basic form to framework 40, can limit thus the progress path of input voice.The first and second vibrating membrane 12,22 also can be formed on the surface of framework 40.Perhaps, the first and second vibrating membrane 12,22 also can with the inside that is formed on opening (voice entrance port) on framework 40 and relatively is configured in framework 40.And the first and second vibrating membrane 12,22 also can be configured to from the distance of sound source (the model sound sources of incident voice) different.For example, as shown in Figure 1, can make the progress path of input voice along the basic form of framework 40 surface extensions to framework 40 settings.And, can be along progress path configuration first and second vibrating membrane 12,22 of input voice.And, can with the vibrating membrane of upstream side of progress path that is configured in the input voice as the first vibrating membrane 12, will be configured in the vibrating membrane in downstream as the second vibrating membrane 22.

The speech input device of present embodiment can also comprise arithmetic processing section 50.The differential signal that arithmetic processing section 50 generates based on differential signal generating unit 30 carries out various calculation process.Arithmetic processing section 50 also can be carried out dissection process to differential signal.Arithmetic processing section 50 also can be undertaken be used to determining to have sent the processing (so-called voice authentication processing) of inputting the people of voice by resolving differential signal.Perhaps, arithmetic processing section 50 also can be carried out processing (so-called voice recognition processing) for the content of determining the input voice by differential signal being carried out dissection process.Arithmetic processing section 50 also can be carried out for the processing that generates various command based on the input voice.Arithmetic processing section 50 also can be carried out the processing for amplified difference signal.In addition, arithmetic processing section 50 also can be controlled the action of communication process described later section 60.In addition, arithmetic processing section 50 also can process to realize above-mentioned each function by the signal of CPU, memory.

Arithmetic processing section 50 both can be configured in the inside of framework 40, also can be configured in the outside of framework 40.When arithmetic processing section 50 was configured in framework 40 outside, arithmetic processing section 50 can obtain differential signal by communication process described later section 60.

The speech input device of present embodiment can also comprise communication process section 60.Communication process section 60 is used for controlling communicating by letter of speech input device and other terminal (mobile telephone terminal, master computer etc.).Communication process section 60 can have by the function of network to other terminal transmitted signal (differential signal).In addition, communication process section 60 also can have and receives the function of signal by network from other terminal.And, for example, also can be in master computer the differential signal of obtaining by communication process section 60 be carried out dissection process, carry out voice recognition processing or voice authentication is processed, order generates the various information processings such as processing, data storage processing with this.That is, speech input device can by with other terminal cooperate with the configuration information treatment system.In other words, speech input device can be considered as be used to the input information terminal of constructing information processing system.But speech input device also can form the structure with communication process section 60.

The speech input device of present embodiment can also have the speech input devices such as display unit, loud speaker such as display floater.In addition, the speech input device of present embodiment can also comprise the operation keys for input operation information.

The speech input device of present embodiment can have above structure.If adopt this speech input device, pass through the simple processing of the difference of output first and second voltage signal, can generate the signal (voltage signal) of the removed phonetic element of expression noise composition.Therefore, according to the present invention, can provide the speech input device that to realize miniaturization and have excellent noise removal function.In addition, about its principle, carry out in the back detailed narration.

2. noise removal function

Below, the noise removal principle that the speech input device of present embodiment is adopted and be used for realizing that the condition of this principle describes.

(1) noise removal principle

At first, the noise removal principle of the speech input device of present embodiment described.

Sound wave is along with front in medium and then decay, and its acoustic pressure (intensity/amplitude of sound wave) descends.Due to acoustic pressure be inversely proportional to from the distance of sound source, therefore can be shown as with acoustic pressure P with from the relation table apart between r of sound source:

$P=K\frac{1}{R}---\left(1\right)$

In addition, in formula (1), k is proportionality constant.Fig. 4 shows the curve chart of expression (1), and from this figure as can be known, acoustic pressure (amplitude of sound wave) is (left side of curve chart) sharp-decay in the position close to sound source, and more decays more reposefully away from sound source.In the speech input device of present embodiment, utilize this attenuation characteristic to remove the noise composition.

That is, in the speech input device of closely saying formula, the user than the sound source of noise more near first and the position of second microphone 10,20 (the first and second vibrating membrane 12,22) send voice.Therefore, between the first and second vibrating membrane 12,22, user's voice are significantly decayed, thus first and the intensity of the user speech that comprises of second voltage signal between difference appears.On the contrary, it is far away that its sound source compared in noise composition and user's voice, therefore decays hardly between the first and second vibrating membrane 12,22.Therefore, can think first and the intensity of the noise that comprises of second voltage signal in difference does not appear.From the foregoing, if detect first and second voltage signal poor, can abate the noise, therefore can obtain and not contain voltage signal (differential signal) the noise composition, that only represent user's phonetic element.That is, differential signal can be considered as representing the signal of the removed user speech of noise composition.

Wherein, sound wave has phase component.Therefore, realize the noise removal function that reliability is high, need to consider first and the second voltage signal in the phonetic element that contains and the phase difference of noise composition.

Below, the actual conditions that speech input device should satisfy in order to realize the noise removal function by the generation differential signal is described.

(2) the speech input device actual conditions that should satisfy

As previously described, the speech input device of present embodiment will represent first and the differential signal of the difference of second voltage signal be considered as not comprising the input speech signal of noise.In the situation that adopt this speech input device, if be included in differential signal the noise composition less than be included in first or the second voltage signal in the noise composition, can be evaluated as and realize the noise removal function.In detail, if the intensity relative inclusion that expression is included in the noise composition in differential signal first or the second voltage signal in the noise intensity ratio of ratio of intensity of noise composition, the intensity relative inclusion that is included in the phonetic element in differential signal less than expression first or the second voltage signal in the voice strength ratio of ratio of intensity of phonetic element, can be evaluated as and realize this noise removal function.

Below, the actual conditions that speech input device (the first and second vibrating membrane 12,22) should satisfy in order to realize this noise removal function is described.

At first, research is to first and the acoustic pressure of the voice of second microphone 10,20 (the first and second vibrating membrane 12,22) incident.If be R from the sound source of input voice (user's voice) to the distance of the first vibrating membrane 12, and ignore phase difference, so can with first and acoustic pressure (intensity) P (S1) and the P (S2) of second microphone 10,20 obtainable input voice be expressed as:

$\left\{\begin{array}{cc}P\left(S1\right)=K\frac{1}{R}& \left(2\right)\\ P\left(S2\right)=K\frac{1}{R+\mathrm{\Δr}}& \left(3\right)\end{array}\right.$

Therefore, voice strength ratio ρ (p) can be expressed as:

$\begin{array}{c}\mathrm{\ρ}\left(P\right)=\frac{P\left(S1\right)-P\left(S2\right)}{P\left(S1\right)}\\ =\frac{\mathrm{\Δr}}{R+\mathrm{\Δr}}\end{array}---\left(4\right)$

Described voice strength ratio ρ (p) refers to, the ratio of the intensity of the input phonetic element that the first microphone 10 the when intensity that expression is included in the input phonetic element in differential signal has been ignored the phase difference of input voice relatively is obtained.

At this, the speech input device of present embodiment is the speech input device of closely saying formula, can think that Δ r is enough less than R.

Therefore, above-mentioned formula (4) can be deformed into:

$\mathrm{\ρ}\left(P\right)=\frac{\mathrm{\Δr}}{R}---\left(A\right)$

That is, from the foregoing, in the situation that ignored the phase difference of input voice, the voice strength ratio can be expressed as formula (A).

Yet, when considering the phase difference of input voice, acoustic pressure Q (S1) and the Q (S2) of user speech can be expressed as:

$\left\{\begin{array}{cc}Q\left(S1\right)=K\frac{1}{R}\sin \mathrm{\ωt}& \left(5\right)\\ Q\left(S2\right)=K\frac{1}{R+\mathrm{\Δr}}\sin (\mathrm{\ωt}-\mathrm{\α})& \left(6\right)\end{array}\right.$

In addition, in formula, α is phase difference.

At this moment, voice strength ratio ρ (S) is:

$\begin{array}{c}\mathrm{\ρ}\left(S\right)=\frac{{|P\left(S1\right)-P\left(S2\right)|}_{\max }}{{\left|P\left(S1\right)\right|}_{\max }}\\ =\frac{|{\frac{K}{R}\sin \mathrm{\ωt}-\frac{K}{R+\mathrm{\Δr}}\sin (\mathrm{\ωt}-\mathrm{\α})|}_{\max }}{{\left|\frac{K}{R}\sin \mathrm{\ωt}\right|}_{\max }}\end{array}---\left(7\right)$

When consideration formula (7), the size of voice strength ratio ρ (S) can be expressed as:

$\begin{array}{c}\mathrm{\ρ}\left(S\right)=\frac{\frac{K}{R}{|\sin \mathrm{\ωt}-\frac{1}{1+\mathrm{\Δr}/R}\sin (\mathrm{\ωt}-\mathrm{\α})|}_{\max }}{\frac{K}{R}{\left|\sin \mathrm{\ωt}\right|}_{\max }}\\ =\frac{1}{1+\mathrm{\Δr}/R}{|(1+\mathrm{\Δr}/R)\sin \mathrm{\ωt}-\sin (\mathrm{\ωt}-\mathrm{\α})|}_{\max }\\ =\frac{1}{1+\mathrm{\Δr}/R}{|\sin \mathrm{\ωt}-\sin (\mathrm{\ωt}-\mathrm{\α})+\frac{\mathrm{\Δr}}{R}\sin \mathrm{\ωt}|}_{\max }\end{array}---\left(8\right)$

In formula (8), the strength ratio of sin ω t-sin (ω t-α) expression phase component, Δ r/Rsin ω t item represents the strength ratio of amplitude composition.Even input phonetic element, but the phase difference composition is noise for the amplitude composition, therefore in order to extract accurately input voice (user speech), the strength ratio that must make phase component is enough less than the strength ratio of amplitude composition.That is, sin ω t-sin (ω t-α) and Δ r/Rsin ω t need to satisfy following relation:

${\left|\frac{\mathrm{\Δr}}{R}\sin \mathrm{\ωt}\right|}_{\max }>{|\sin \mathrm{\ωt}-\sin (\mathrm{\ωt}-\mathrm{\α})|}_{\max }---\left(B\right)$

Wherein,

$\sin \mathrm{\ωt}-\sin (\mathrm{\ωt}-\mathrm{\α})=2\sin \frac{\mathrm{\α}}{2}\·\cos (\mathrm{\ωt}-\frac{\mathrm{\α}}{2})---\left(9\right)$

Therefore, above-mentioned formula (B) can be expressed as:

${\left|\frac{\mathrm{\Δr}}{R}\sin \mathrm{\ωt}\right|}_{\max }{>|2\sin \frac{\mathrm{\α}}{2}\·\cos (\mathrm{\ωt}-\frac{\mathrm{\α}}{2})|}_{\max }---\left(10\right)$

From the foregoing, if the amplitude composition of consideration formula (10), the speech input device of present embodiment need to satisfy following formula:

$\frac{\mathrm{\Δr}}{R}>2\sin \frac{\mathrm{\α}}{2}---\left(C\right)$

In addition, as mentioned above, can think Δ r enough less than R, so can think that sin (α/2) is enough little, therefore it can be approximately:

$\sin \frac{\mathrm{\α}}{2}\≈\frac{\mathrm{\α}}{2}---\left(11\right)$

Therefore, formula (C) can be deformed into:

$\frac{\mathrm{\Δr}}{R}>\mathrm{\α}---\left(D\right)$

In addition, if will be expressed as formula as the α of phase difference and the relation between Δ r:

$\mathrm{\α}=\frac{2\mathrm{\π\Δr}}{\mathrm{\λ}}---\left(12\right)$

, formula (D) can be deformed into:

$\frac{\mathrm{\Δr}}{R}>2\mathrm{\π}\frac{\mathrm{\Δr}}{\mathrm{\λ}}>\frac{\mathrm{\Δr}}{\mathrm{\λ}}---\left(E\right)$

That is, in the present embodiment, in order to extract accurately input voice (user speech), speech input device need to be manufactured and satisfy the relation shown in formula (E).

Then, research is to first and the acoustic pressure of the noise of second microphone 10,20 (the first and second vibrating membrane 12,22) incident.

If with first and the amplitude of the obtained noise composition of second microphone be made as A, A ', acoustic pressure Q (N1) and the Q (N2) that has considered the noise of phase difference composition can be expressed as:

$\left\{\begin{array}{cc}Q\left(N1\right)=A\sin \mathrm{\ωt}& \left(13\right)\\ Q\left(N2\right)=A^{\′}\sin (\mathrm{\ωt}-\mathrm{\α})& \left(14\right)\end{array}\right.$

Noise intensity can be expressed as than ρ (N):

$\begin{array}{c}\mathrm{\ρ}\left(N\right)=\frac{{|Q\left(N1\right)-Q\left(N2\right)|}_{\max }}{{\left|Q\left(N1\right)\right|}_{\max }}\\ =\frac{{|A\sin \mathrm{\ωt}-A^{\′}\sin (\mathrm{\ωt}-\mathrm{\α})|}_{\max }}{{\left|A\sin \mathrm{\ωt}\right|}_{\max }}\end{array}---\left(15\right)$

Described noise intensity refers to than ρ (N), and expression is included in the ratio of the intensity of the obtained noise composition of relative first microphone 10 of intensity of the noise composition in differential signal.

In addition, as previously described, first and the amplitude (intensity) of the obtained noise composition of second microphone roughly the same, so can be considered as A=A '.Therefore, above-mentioned formula (15) can be deformed into:

$\mathrm{\ρ}\left(N\right)=\frac{{|\sin \mathrm{\ωt}-\sin (\mathrm{\ωt}-\mathrm{\α})|}_{\max }}{{\left|\sin \mathrm{\ωt}\right|}_{\max }}---\left(16\right)$

And, the size of noise intensity ratio can be expressed as:

$\begin{array}{c}\mathrm{\ρ}\left(N\right)=\frac{{|\sin \mathrm{\ωt}-\sin (\mathrm{\ωt}-\mathrm{\α})|}_{\max }}{{\left|\sin \mathrm{\ωt}\right|}_{\max }}\\ ={|\sin \mathrm{\ωt}-\sin (\mathrm{\ωt}-\mathrm{\α})|}_{\max }\end{array}---\left(17\right)$

At this, if consider above-mentioned formula (9), formula (17) can be deformed into:

$\begin{array}{c}\mathrm{\ρ}\left(N\right)={\left|\cos (\mathrm{\ωt}-\frac{\mathrm{\α}}{2})\right|}_{\max }\·2\sin \frac{\mathrm{\α}}{2}\\ =2\sin \frac{\mathrm{\α}}{2}\end{array}---\left(18\right)$

Then, if consideration formula (11) can be deformed into formula (18):

ρ(N)＝α (19)

At this, if with reference to formula (D), the noise intensity ratio can be expressed as:

$\mathrm{\&rho;}\left(N\right)=\mathrm{\&alpha;}<\frac{\mathrm{\&Delta;r}}{R}---\left(F\right)$

In addition, shown in (A), Δ r/R is the strength ratio of the amplitude composition of input voice (user speech).From formula (F) as can be known, in this speech input device, noise intensity is than the strength ratio Δ r/R less than the input voice.

From the foregoing, in the speech input device (with reference to formula (B)) of strength ratio less than the strength ratio of amplitude composition of the phase component that is designed to input voice, noise intensity is than less than input voice strength ratios (with reference to formula (F)).On the contrary, be designed to noise intensity than the speech input device less than input voice strength ratio if adopt, can realize the noise removal function that precision is high.

That is, if adopt, the first and second vibrating membrane 12,22 (first and second microphone 10,20) is configured to noise intensity than the speech input device less than the present embodiment of input voice strength ratio, can realizes the noise removal function that precision is high.

3. the manufacture method of speech input device

Below, the manufacture method of the speech input device of present embodiment is described.In the present embodiment, utilize value and the noise intensity of expression Δ r/ λ to make speech input device than the data of the corresponding relation between (strength ratio of the phase component of noise), wherein, the ratio of the wavelength X of the value representation first of described Δ r/ λ and the second vibrating membrane 12,22 distance between centers Δ r and noise.

The strength ratio of the phase component of noise can be expressed as above-mentioned formula (18).Therefore, the decibel value of the strength ratio of the phase component of noise can be expressed as:

$20\log \mathrm{\&rho;}\left(N\right)=20\log \left|2\sin \frac{\mathrm{\&alpha;}}{2}\right|---\left(20\right)$

And, to each value of the α substitution of formula (20), can clear and definite phase difference α and the strength ratio of the phase component of noise between corresponding relation.One example of the phase difference when Fig. 5 shows the expression transverse axis and gets the strength ratio (decibel value) that α/2 π, the longitudinal axis get the phase component of noise and the data of the corresponding relation between strength ratio.

In addition, shown in (12), can utilize the function of the ratio Δ r/ λ of distance, delta r and wavelength X to represent phase difference α, so the transverse axis of Fig. 5 can be considered as Δ r/ λ.That is, can say that Fig. 5 is for the strength ratio of the phase component that represents noise and the data of the corresponding relation between Δ r/ λ.

In the present embodiment, utilize these data to make speech input device.Fig. 6 utilizes these data to make the flow chart of the step of speech input device for explanation.

At first, prepare the strength ratio (strength ratio of the phase component of noise) of expression noise and the data (with reference to Fig. 5) (step S10) of the corresponding relation between Δ r/ λ.

Then, according to purposes, set the strength ratio (step S12) of noise.In addition, in the present embodiment, need so that the mode that the intensity of noise descends is set the strength ratio of noise.Therefore, in this step, the strength ratio of noise is set as below 0dB.

Then, according to these data, the value (step S14) of the Δ r/ λ that derives corresponding with the strength ratio of noise.

Then, by the wavelength to the main noise of λ substitution, the condition (step S16) that derivation Δ r/ λ should satisfy.

As concrete example, consider to make the situation of following speech input device: in this speech input device, be that 1kHz, its wavelength are under the environment of 0.347m at main noise, the intensity decline 20dB of noise.

At first, as necessary condition, research makes the strength ratio of noise become the following condition of 0dB.With reference to Fig. 5 as can be known, the strength ratio of noise is become below 0dB, the value of Δ r/ λ is made as below 0.16 and get final product.That is, Δ r value is made as below 55.46mm gets final product, the necessary condition of Here it is this speech input device.

Then, consideration is for the condition of the intensity decline 20dB of the noise that makes 1kHz.With reference to Fig. 5 as can be known, make the intensity decline 20dB of noise, as long as the value of Δ r/ λ is made as 0.015.And, if establish λ=0.347m, when the value of Δ r be that 5.20mm satisfies this condition when following.That is, if Δ r is set as approximately below 5.2mm, can make the speech input device of the formula of closely saying with noise removal function.

In addition, the speech input device of present embodiment is the speech input device of closely saying formula, and the interval between the sound source of user speech and the first or second vibrating membrane 12,22 is generally below 5cm.In addition, can by the design to framework 40, can control the sound source of user speech and the interval between the first and second vibrating membrane 12,22.Therefore, the value of the strength ratio Δ r/ λ of input voice (user speech) is greater than 0.1 (strength ratio of noise), so can realize the noise removal function.

In addition, usually, noise is not limited to single-frequency.But frequency ratio is envisioned for the low noise of noise of main noise, and this main noise of its wavelength ratio is longer, so the value of Δ r/ λ diminishes, so can be removed by this speech input device.In addition, if the decay of the higher energy of sound wave frequency is just faster.Therefore, frequency ratio is envisioned for the high noise of noise of main noise and decays more quickly than this main noise, therefore can ignore the impact that speech input device is brought.From the foregoing, even under the environment that has the frequency noise different from the noise that is envisioned for main noise, the speech input device of present embodiment also can be brought into play excellent noise removal function.

In addition, in the present embodiment, also can know from formula (12), the prerequisite of present embodiment is, noise is along connecting the first and second vibrating membrane 12,22 straight line top incident.This noise is the noise that makes the first and second vibrating membrane 12,22 apparent interval become maximum, and is the noise that makes phase difference become maximum under the environment for use of reality.That is, the speech input device of present embodiment has the structure of the noise that can remove the phase difference maximum.Therefore, if adopt the speech input device of present embodiment, can remove from the noise of all direction incidents.

4. effect

Below, the effect of the speech input device of present embodiment is described.

As previously described, if adopt the speech input device of present embodiment, only just can obtain the removed phonetic element of noise composition by generating differential signal, described differential signal represents first and the difference of second microphone 10,20 obtained voltage signals.That is, in this speech input device, need not to carry out complicated parsing calculation process and just can realize the noise removal function.Therefore, according to present embodiment, can provide the speech input device that just can realize the noise removal function that precision is high with simple structure.

In addition, in this speech input device, make based on the strength ratio of the noise of the phase difference strength ratio less than the input voice, realize thus the noise removal function.Yet, based on the noise intensity of phase difference than changing according to the first and second vibrating membrane 12,22 orientation and the incident direction of noise.That is, wider with respect to the interval (apparent interval) between first and second vibrating membrane 12,22 of noise, the phase difference of noise is just larger, makes based on the noise intensity of phase difference larger than change.Yet in the present embodiment, from formula (12) also as can be known, speech input device has can remove the structure that makes the noise that the first and second vibrating membrane 12,22 apparent interval become the widest.In other words, in the present embodiment, the first and second vibrating membrane 12,22 is configured to remove the noise intensity that makes based on phase difference than the noise of large ground incident that becomes.Therefore, if adopt this speech input device, just can remove the noise from comprehensive incident.That is, according to the present invention, can provide the speech input device that to remove from the noise of comprehensive incident.

In addition, if adopt this speech input device, can also remove the user speech composition that is incided after the reflections such as wall in speech input device.In detail, can think far away than the sound source of common user speech by the sound source of the user speech of the reflections such as wall, and because a large amount of energy has been lost in reflection, therefore same with the noise composition, acoustic pressure can significantly decay between the first and second vibrating membrane 12,22.Therefore, if adopt this speech input device, with noise similarly, incided user speech composition in speech input device (as noise a kind of) after the reflections such as wall and also be removed.

And, if utilize this speech input device, just can obtain the signal of the expression input voice that do not comprise noise.Therefore, by utilizing this speech input device, can realize that the high speech recognition of precision, voice authentication or order generate processing.

In addition, if this speech input device is applicable to microphone system, the sound from the user of loud speaker output also is removed as noise.Therefore, can provide the microphone system that is difficult for occuring singing (howling).

5. the speech input device of the second execution mode

Then, with reference to Fig. 7, the speech input device of having used the second execution mode of the present invention is described.

The speech input device of present embodiment comprises base portion 70.Be formed with recess 74 on the interarea 72 of base portion 70.And, in the speech input device of present embodiment, dispose the first vibrating membrane 12 (the first microphone 10) on the bottom surface 75 of recess 74, dispose the second vibrating membrane 22 (second microphone 20) on the interarea 72 of base portion 70.In addition, recess 74 can vertically extend with interarea 72, and the bottom surface 75 of recess 74 can be the face parallel with interarea 72.Bottom surface 75 can be also the face vertical with recess 74.In addition, recess 74 also can have the profile identical with the first vibrating membrane 12.

In the present embodiment, recess 74 can be more shallow than the interval between zone 76 and opening 78.That is, if the degree of depth of recess 74 is made as d, the interval between zone 76 and opening 78 is made as Δ G, base portion 70 can satisfy d≤Δ G.Base portion 70 also can satisfy 2d=Δ G.In addition, Δ G can be below 5.2mm.Perhaps, also can to have the air line distance that connects the first and second vibrating membrane 12,22 center be the following structure of 5.2mm to base portion 70.

Base portion 70 is configured to: the opening 78 that is communicated with recess 74 is configured in the position than the sound source of the more close input voice in zone 76 of configuration the second vibrating membrane 22 on interarea 72.Base portion 70 can be configured to input voice and arrive simultaneously the first and second vibrating membrane 12,22.For example, it is identical with the interval between model sound source and the second vibrating membrane 22 that base portion 70 can be configured to make sound source (model sound source) and the interval between the first vibrating membrane 12 of input voice.Base portion 70 also can be arranged in the framework that is set with the basic form that satisfies above-mentioned condition.

If adopt the speech input device of present embodiment, can reduce poor to time of incidence of the input voice (user speech) of the first and second vibrating membrane 12,22 incidents.That is, owing to generating differential signal in the mode that does not comprise the phase difference composition of inputting voice, so can extract accurately the amplitude composition of input voice.

In addition, sound wave is in the interior indiffusion of recess 74, so the amplitude of sound wave is decayed hardly.Therefore, in this speech input device, can think that the intensity (amplitude) of the input voice that make the first vibrating membrane 12 vibration is identical with the intensity of the input voice at opening 78 places.Thus, even make the input voice arrive simultaneously the first and second vibrating membrane 12,22 in the situation that speech input device has, also can on the intensity of the input voice that make the first and second vibrating membrane 12,22 vibrations, difference appear.Therefore, by obtaining the differential signal of expression first and the difference of second voltage signal, can extract the input voice.

In sum, if adopt this speech input device, can obtain in the mode of the noise that do not comprise the phase difference composition of inputting voice the amplitude composition (differential signal) of input voice.Therefore, can realize the noise removal function that precision is high.

In addition, be made as (5.2mm is following) below Δ G by the degree of depth with recess 74, can set the resonance frequency of recess 74 higher, therefore can prevent at recess 74 places generation resonance noise.

Fig. 8 shows the variation of the speech input device of present embodiment.

The speech input device of present embodiment comprises base portion 80.On the interarea 82 of base portion 80, be formed with the first recess 84 and shallow the second recess 86 than the first recess 84.The difference Δ d of the first and second recess 84,86 the degree of depth can less than the first opening 85 that is communicated with the first recess 84 and with the second opening 87 that the second recess 86 is communicated with between interval delta G.And the first vibrating membrane 12 is configured in the bottom surface of the first recess 84, and the second vibrating membrane 22 is configured in the bottom surface of the second recess 86.

Even adopt this speech input device, also can bring into play and above-mentioned same effect, therefore can realize high-precision noise removal function.

At last, in Fig. 9～Figure 11, the example as the speech input device of embodiment of the present invention represents respectively mobile phone 300, microphone (microphone system) 400 and remote controller 500.In addition, Figure 12 shows the skeleton diagram that comprises as the information processing system 600 of the speech input device 602 of input information terminal and master computer 604.

6. the structure of the speech input device of the 3rd execution mode

Figure 13 is the schematic diagram of an example of structure of the speech input device of the 3rd execution mode.

The speech input device 700 of the 3rd execution mode comprises the first microphone 710-1 with first vibrating membrane.In addition, the speech input device 700 of the 3rd execution mode comprises the second microphone 710-2 with second vibrating membrane.

the first vibrating membrane of the first microphone 710-1 and the second vibrating membrane of second microphone 710-2 are configured to the noise intensity ratio less than input voice strength ratio, wherein, described noise intensity is included in the noise composition in differential signal 742 than expression intensity relative inclusion is described first or second voltage signal 712-1, the ratio of the intensity of the described noise composition in 712-2, the intensity relative inclusion that described input voice strength ratio represents to be included in the input phonetic element in described differential signal 742 described first or the second voltage signal in the ratio of intensity of described input phonetic element.

In addition, have the first microphone 710-1 and the second microphone 710-2 with second vibrating membrane of the first vibrating membrane, also can have structure as described in Fig. 1～Fig. 8.

The speech input device 700 of the 3rd execution mode comprises differential signal generating unit 720, the first voltage signal 712-1 that this differential signal generating unit 720 is obtained according to described the first microphone 710-1 and the obtained second voltage signal 712-2 of described second microphone, the differential signal 742 of generation the first voltage signal 712-1 and second voltage signal 712-2.

In addition, differential signal generating unit 720 comprises delay section 730.730 pairs, delay section at least one voltage signal in obtained the first voltage signal 712-1 of described the first microphone and the obtained second voltage signal 712-2 of described second microphone give regulation postpone after output.

In addition, differential signal generating unit 720 comprises differential signal efferent 740.Differential signal efferent 740 receives by described delay section and has given at least one voltage signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone the signal that postpones, the differential signal that generates the first voltage signal and the second voltage signal line output of going forward side by side.

Delay section 730 can arrange to the first obtained voltage signal 712-1 of the first microphone give regulation postpone after output the first delay 732-1 of section and to second voltage signal 712-2 give regulation postpone after some in the second delay 782-2 of section of output, some voltage signals are postponed, thereby generate differential signal.The first delay 732-1 of section and the second delay 732-2 of section also can be set, the first voltage signal 712-1 and second voltage signal 712-2 are postponed, thereby generate differential signal.When both of the first delay 732-1 of section and the second delay 732-2 of section are set, can be with some delay wherein section as the delay section that gives fixed delay, with another delay section as the variable delay section that can adjust changeably delay.

Thus, postpone by at least one voltage signal in the first voltage signal 712-1 and second voltage signal 712-2 being given regulation, can proofread and correct the deviation of the delay of that individual difference when making microphone causes, the first voltage signal and second voltage signal, therefore can prevent the noise suppression effect decline that the deviation because of the delay of the first voltage signal and second voltage signal causes.

Figure 14 is the schematic diagram of an example of structure of the speech input device of the 3rd execution mode.

The differential signal generating unit 720 of present embodiment can comprise delay control part 734.Postpone the control that control part 734 changes the retardation in delay section (being the first delay 732-1 of section at this).Also can by postponing control part 734 dynamically or the retardation of control lag section (being the first delay 732-1 of section at this) statically, adjust thus the signal delay balance between the obtained second voltage signal 712-2 of the delay output S1 of section and described second microphone.

Figure 15 is the schematic diagram of an example of delay section and the concrete structure that postpones control part.For example, can consist of delay section (being the first delay 732-1 of section at this) by analog filters such as group delay filters.For example, postponing control part 734 can or flow through the magnitude of current between control terminal 736-GND according to the voltage between the control terminal 736-GND of group delay filter 732-1, dynamically or statically controls the retardation of group delay filter.

Figure 16 A (Figure 16 B) is an example of structure of controlling statically the retardation of group delay filter.

For example, as shown in Figure 16 A, can comprise the electric resistance array that is connected in series with a plurality of resistive elements (r), and supply with the electric current of prescribed level to the terminal (control terminal 734 of Figure 15) of the regulation of delay section by this electric resistance array.At this, in manufacture process, the size of electric current according to the rules, utilize laser to shear resistive element (r) or the conductor (738 F) that consists of described electric resistance array, perhaps, fuse and consist of resistive element (r) or the conductor (738 F) of described electric resistance array by applying high voltage or high electric current.

In addition, for example, as shown in Figure 16 B, can comprise the electric resistance array that is connected in parallel to a plurality of resistive elements (r), and supply with the electric current of prescribed level to the terminal (control terminal 734 of Figure 15) of the regulation of delay section by this electric resistance array.At this, in manufacture process, the size of electric current according to the rules, utilize laser to shear resistive element (r) or the conductor (F) that consists of described electric resistance array, perhaps, fuse and consist of resistive element (r) or the conductor (F) of described electric resistance array by applying high voltage or high electric current.

At this, according to the deviation of the delay that produces in manufacture process, the size of electric current of terminal that will flow through the regulation of delay section is set as the value that can eliminate this deviation and gets final product.As shown in Figure 16 A (Figure 16 B), by utilizing the electric resistance array that a plurality of resistive elements (r) arranged connected in series or in parallel, can be made into the resistance value corresponding with the deviation of the delay that produces in manufacture process, performance postpones the function of control part, this postpones control part and is connected with the terminal of regulation, and supply is for the electric current of the retardation of controlling described delay section.

In addition, in the above-described embodiment, for example understand the structure that a plurality of resistive elements (r) link together by fuse (F), but be not limited thereto.Also can adopt a plurality of resistance (r) not pass through fuse (F) and direct structure connected in series or in parallel, at this moment, can cut off at least one resistance.

In addition, also can adopt so-called laser trimming to come the structure of adjusting resistance value, for example, as shown in figure 40, be consisted of resistance R 1 or the R2 of Figure 32 by a resistive element, and cut off the structure of the part of resistive element.

Figure 17 is the schematic diagram of an example of structure of the speech input device of the 3rd execution mode.

Differential signal generating unit 720 can comprise phase difference detection section 750.Phase difference detection section 750 receives the first voltage signal (S1) and the second voltage signal (S2) of the input that becomes differential signal efferent 740, and according to the first voltage signal (S1) that receives and second voltage signal (S2), the first voltage signal (S1) when detecting generation differential signal 742 and the phase difference of second voltage signal (S2), and according to testing result, generate and output phase difference signal (FD).

Postpone control part 734 according to phase signal (FD), can change the retardation in delay section (being the first delay 732-1 of section at this).

In addition, differential signal generating unit 720 can comprise gain section 760.Output after 760 pairs, gain section at least one voltage signal in obtained the first voltage signal of the first microphone 710-1 and the obtained second voltage signal of described second microphone 710-2 is given the regulation gain.

Differential signal efferent 740 can have been given the signal (S2) of gain by receiving by 760 pairs, gain section at least one voltage signal in obtained the first voltage signal of the first microphone 710-1 and the obtained second voltage signal of described second microphone 710-2, generates and export the differential signal of the first voltage signal (S1) and second voltage signal (S2).

For example, output phase difference signal FD after phase difference detection section 740 can carry out computing to the phase difference of the output S1 of delay section (being the first delay 732-1 of section at this) and the gain output S2 of section, postponing control part 734 can according to the polarity of phase signal FD, dynamically change the retardation of delay section (being the first delay 732-1 of section at this).

The first delay 732-1 of section receives the first obtained voltage signal 712-1 of the first microphone 710-1, and the voltage signal S1 of the delay of regulation has been given in output according to delayed control signal (for example, rated current) 735.Gain section 760 receives the obtained second voltage signal 712-2 of second microphone 710-2, and the voltage signal S2 of the gain of regulation has been given in output.Phase signal efferent 754 receives the voltage signal S2 that voltage signal S1 that the first delay 732-1 of section export and gain section 760 export, output phase difference signal FD.Postpone the phase signal FD that control part 734 receiving phase difference signal efferents 754 are exported, output delay control signal (for example, rated current) 735.Can pass through the retardation that this delayed control signal (for example, rated current) 735 is controlled the first delay 732-1 of section, thus the retardation of the first delay 732-1 of section be carried out FEEDBACK CONTROL.

Figure 18 is the schematic diagram of an example of structure of the speech input device of the 3rd execution mode.

Phase difference detection section 720 can comprise the one 2 value 752-1 of section.The one 2 value 752-1 of section carries out 2 values with specified level (1evel) to described the first voltage signal S1 that receives, thereby is converted to the first digital signal D1.

In addition, phase difference detection section 720 can comprise the 22 value 752-2 of section.The 22 value 752-2 of section carries out 2 values with specified level to the described second voltage signal S2 that receives, thereby is converted to the second digital signal D2.

Phase difference detection section 720 comprises phase signal efferent 754.The phase difference that phase signal efferent 754 calculates between the first digital signal D1 and described the second digital signal D2, thereby output phase difference signal FD.

The first delay 732-1 of section receives the first obtained voltage signal 712-1 of the first microphone 710-1, and the signal S1 of the delay of regulation has been given in output according to delayed control signal (for example, rated current) 735.Gain section 760 receives the obtained second voltage signal 712-2 of second microphone 710-2, and the signal S2 of the gain of regulation has been given in output.The one 2 value 752-1 of section receives the first voltage signal S1 that the first delay 732-1 of section exports, and exports the first digital signal D1 that has carried out 2 values with specified level.The second voltage signal S2 that the 22 value 752-2 of section receiving gain section 760 exports, and output the second digital signal D2 of having carried out 2 values with specified level.The second digital signal D2 that the first digital signal D1 that phase signal efferent 754 reception the one 2 value 752-1 of section export and the 22 value 752-2 of section export, and output phase difference signal FD.Postpone the phase signal FD that control part 734 receiving phase difference signal efferents 754 are exported, output delay control signal (for example, rated current) 735.Can pass through the retardation that this delayed control signal (for example, rated current) 735 is controlled the first delay 732-1 of section, carry out thus

The first delay 732-1 of section is carried out the FEEDBACK CONTROL of retardation.

Figure 19 is the sequential chart of phase difference detection section.S1 is the voltage signal that the first delay 732-1 of section exports, and S2 is the voltage signal that gain section exports.Voltage signal S2 is with respect to voltage signal S1, phase delay Δ φ.

D1 is the 2 value signals of voltage signal S1, and D2 is the 2 value signals of voltage signal S2.For example, the signal of D1 or D2 is making voltage signal S1 or S2 by after high pass filter, to carry out the 2 resulting signals of value by comparator (comparator) circuit.

FD is the phase signal that generates according to 2 value signal D1 and 2 value signal D2.For example, as shown in figure 19, when the phase place of the first voltage signal is more leading than the phase place of second voltage signal, can generate respectively to each cycle the positive pulse P of the pulse duration corresponding with the leading phase potential difference, when the phase place of the first voltage signal lags behind than the phase place of second voltage signal, can generate respectively negative pulse with the poor corresponding pulse duration of lagging phase to each cycle.

Figure 21 is the schematic diagram of an example of structure of the speech input device of the 3rd execution mode.

Phase difference detection section 750 comprises the first band pass filter 756-1.The first band pass filter 756-1 is, after received the first voltage signal S1 of input, and the band pass filter that the signal K1 of the single-frequency of regulation is passed through.

Phase difference detection section 750 comprises the second band pass filter 756-2.The second band pass filter 756-2 is, after the received second voltage signal S2 of input, and the band pass filter that the signal K2 of the single-frequency of regulation is passed through.

Phase difference detection section 750 can come detected phase poor according to the first voltage signal K1 and the second voltage signal K2 that have passed through after the first band pass filter 756-1 and the second band pass filter 756-2.

For example, as shown in figure 20, sound source section 770 is configured in from the first microphone 710-1 and second microphone 710-2 equidistant position, generate the sound of single-frequency and receive this sound, utilizing after the first band pass filter 756-1 and the second band pass filter 756-2 cut off the sound of the frequency except the sound of this single-frequency, detected phase is poor, can improve thus the SN ratio of comparison of signal phase, thus the poor or retardation of detected phase accurately.

In addition, even in the situation that speech input device itself does not have sound source section 770, also can when test will test be arranged on sound source temporarily speech input device near, and will test to be set as with sound source and make sound input to the first microphone and second microphone with same phase, and receive sound by the first microphone and second microphone, the waveform of the first voltage signal of exporting and second voltage signal is monitored and changed the retardation of delay section, make the first voltage signal consistent with the phase place of second voltage signal.

The first delay 732-1 of section receives the first obtained voltage signal 712-1 of the first microphone 710-1, and the signal S1 of the delay of regulation has been given in output according to delayed control signal (for example, rated current) 735.Gain section 760 receives the obtained second voltage signal 712-2 of second microphone 710-2, and the signal S2 of the gain of regulation has been given in output.The first band pass filter 756-1 receives the first voltage signal S1 that the first delay 732-1 of section exports, the signal K1 of output single-frequency.The second voltage signal S2 that the second band pass filter 756-2 receiving gain section 760 exports, the signal K2 of output single-frequency.The signal K1 of the single-frequency that the one 2 value 752-1 of section reception the first band pass filter 756-1 exports, the first digital signal D1 that output has been carried out 2 values with specified level.The signal K2 of the single-frequency that the 22 value 752-2 of section reception the second band pass filter 756-2 exports, the second digital signal D2 that output has been carried out 2 values with specified level.The second digital signal D2 that the first digital signal D1 that phase signal efferent 754 reception the one 2 value 752-1 of section export and the 22 value 752-2 of section export, output phase difference signal FD.Postpone the phase signal FD that control part 734 receiving phase difference signal efferents 754 are exported, output delay control signal (for example, rated current) 735.Can pass through the retardation that this delayed control signal (for example, rated current) 735 is controlled the first delay 732-1 of section, thus the retardation of the first delay 732-1 of section be carried out FEEDBACK CONTROL.

Figure 22 A (Figure 22 B) is the key diagram of the directive property of differential microphone.

Figure 22 A is illustrated in the directional property under the state that the phase place of two microphone M1, M2 is offset.The circle regional 810-1 of shape and 810-2 represent the directional property that the difference according to the output of two microphone M1, M2 obtains, this directional property represents double directing property, both, the rectilinear direction of supposing connection two microphone M1, M2 is 0 degree, 180 degree, the direction vertical with the rectilinear direction that is connected two microphone M1, M2 is made as 90 degree, 270 degree, have maximum sensitivity on 0 degree, 180 degree directions, do not have sensitivity on 90 degree, 270 degree directions.

When a signal in the signal obtained to two microphone M1, M2 had been given delay, directional property changed.For example, when the output for microphone M1, given be equivalent to microphone interval d divided by velocity of sound C the delay of time the time, the zone of the directive property of expression two microphone M1, M2 become Figure 22 B 820 shown in heart.In this case, can realize not having the directional property of sensitivity (invalid (null)) for speaker's direction of 0 degree, thus speaker's voice can optionally be interdicted, thus the sound (noise on every side) around can only obtaining.

Utilize above-mentioned characteristic, the state of the noise level (level) around can detecting.

Figure 23 is the schematic diagram of an example of structure with speech input device of noise detection unit.

The speech input device of present embodiment comprises that noise measuring is with delay section 780.Noise measuring is given after the delay that noise measuring uses its output with the obtained second voltage signal 712-2 of delay 780 couples of second microphone 710-2 of section.

The speech input device of present embodiment comprises noise measuring differential signal generating unit 782.Noise measuring detects the differential signal 783 of use with differential signal generating unit 782 generted noises, these differential signal 783 expression noise measurings have been given the poor of the signal 781 of the regulation delay that noise measuring uses and obtained the first voltage signal 712-1 of described the first microphone 710-1 with delay section 780.

The speech input device of present embodiment comprises noise measuring section 784.The differential signal 783 that noise measuring section 784 uses according to noise measuring judges the level of noise, and comes output noise detection signal 785 according to judged result.Noise measuring section 784 also can calculate the average level of the differential signal that noise measuring uses, and generates according to average level the differential signal 785 that noise measuring is used.

The speech input device of present embodiment comprises signal switching part 786.Signal switching part 786 receives differential signal 742 and the first obtained voltage signal 712-1 of described the first microphone that differential signal generating unit 720 is exported, and switches output the first voltage signal 712-1 and described differential signal 742 according to described noise detecting signal 785.Signal switching part 786 can be specified level when following in noise level, exports the first obtained voltage signal of described the first microphone, at described average level output difference sub-signal during greater than specified level.Like this, under quiet environment (noise level is below specified level), the sound that the good single microphone of output SNR (Signal to Noise Ratio:SN ratio, signal to noise ratio) obtains.In addition, under the environment (noise level is more than specified level) of high noisy, the sound that the differential microphone that the output noise removal capacity is good obtains.

At this, the differential signal generating unit can have in Figure 13, Figure 14, Figure 17, Figure 18, structure illustrated in fig. 21, also can have the structure of well-known general differential microphone.in addition, the first vibrating membrane of the first microphone 710-1 and the second vibrating membrane of second microphone 710-1 can have and be configured to noise intensity than the structure less than input voice strength ratio, but also can have other structures that there is no such restriction, wherein, described noise intensity is included in the noise composition in described differential signal 742 than expression intensity relative inclusion described first or the second voltage signal in the ratio of intensity of described noise composition, the intensity relative inclusion that described input voice strength ratio represents to be included in the input phonetic element in described differential signal described first or the second voltage signal in the ratio of intensity of described input phonetic element.

In addition, the delay used of described noise measuring can not be also with the distance between centers (with reference to the d in Figure 20) of the first and second vibrating membrane time divided by the velocity of sound gained.Even in the situation that speaker's direction is not 0 degree direction, as long as the direction that does not have sensitivity (invalid) of directional property can be set on speaker's direction, just can realize being suitable for having blocking speaker's voice and pick up the characteristic of noise measuring of the directive property of ambient noise.For example, also can will postpone to be set as the directional property with high heart-shaped (hypercardioid), super heart-shaped (supercardioid), thus blocking speaker voice.

Differential signal generating unit 720 receives obtained the first voltage signal 712-1 and the obtained second voltage signal 712-2 of second microphone 710-2 of the first microphone 710-1, generates and output difference sub-signal 742.

Noise measuring receives the obtained second voltage signal 712-2 of second microphone 710-2 with delay section 780, and the signal 781 of the delay that noise measuring uses has been given in output.Noise measuring generates with differential signal generating unit 782 and output noise detects the differential signal 783 of use, and these differential signal 783 expression noise measurings have been given the poor of the signal 781 of the regulation delay that noise measuring uses and obtained the first voltage signal 712-1 of described the first microphone 710-1 with delay section 780.Noise measuring section 784 receives the differential signal 783 that noise measuring is used, and the differential signal 783 of using according to noise measuring judges the level of noise, and comes output noise detection signal 785 according to judged result.

Signal switching part 786 receives obtained the first voltage signal 712-1 and the noise detecting signal 785 of differential signal 742, described the first microphone that differential signal generating unit 720 is exported, and switches output the first voltage signal 712-1 and described differential signal 742 according to noise detecting signal 785.

Figure 24 means that the signal that is undertaken by noise measuring switches the flow chart of the example of action.

The noise detecting signal of exporting when noise measuring section is during less than the threshold value (LTH) of regulation (step S120), the signal (step S112) of the single microphone of signal switching part output, when the noise detecting signal of exporting when noise measuring section is not less than the threshold value (LTH) of regulation (step S110), the signal (step S114) of signal switching part output differential microphone.

In addition, have the speech input device for the loud speaker of output sound information, also can comprise the volume control section of coming the volume of control loudspeaker according to noise detecting signal.

Figure 25 means the flow chart of example of the volume control action of the loud speaker that is undertaken by noise measuring.

The noise detecting signal of exporting when noise measuring section is during less than the threshold value (LTH) of regulation (step 120), be the first value (step S122) with the sound volume setting of loud speaker, when the noise detecting signal of exporting when noise measuring section is not less than the threshold value (LTH) of regulation (step S120), be the second value with the sound volume setting of loud speaker, the volume of the second value is greater than the volume (step S124) of the first value.

In addition, in the time of also can working as noise detecting signal that noise measuring section exports less than the threshold value (LTH) of regulation, reduce the volume of loud speaker, when the noise detecting signal of exporting when noise measuring section is not less than the threshold value (LTH) of regulation, improve the volume of loud speaker.

Figure 26 is the schematic diagram of an example of structure with speech input device of AD converting unit.

The speech input device of present embodiment can comprise an AD converting unit 790-1.The one AD converting unit 790-1 carries out analog/digital conversion to the first obtained voltage signal 712-1 of the first microphone 710-1.

The speech input device of present embodiment can comprise the 2nd AD converting unit 790-2.The 2nd AD converting unit 790-2 carries out analog/digital conversion to the obtained second voltage signal 712-2 of second microphone 710-2.

The speech input device of present embodiment comprises differential signal generating unit 720.Differential signal generating unit 720 can according to described the first voltage signal 782-1 that converts digital signal by an AD converting unit 790-1 to and the described second voltage signal 782-2 that converts digital signal by described the 2nd AD converting unit 790-2 to, generate the differential signal 742 of the first voltage signal and second voltage signal.

At this, differential signal generating unit 720 can adopt in Figure 13, Figure 14, Figure 17, Figure 18, structure illustrated in fig. 21.The delay of differential signal generating unit 720 can be set as the integral multiple of change-over period of the analog/digital conversion of an AD converting unit 790-1 or the 2nd AD converting unit 790-2.Like this, delay section makes input signal skew 1 clock (clock) or number clock by trigger (flip-flop) with digital form, can realize thus postponing.

In addition, the distance between centers of the second vibrating membrane of the first vibrating membrane of the first microphone 710-1 and second microphone 710-2 can be set as the change-over period of analog/digital conversion be multiply by the resulting value of velocity of sound or its integral multiple.

Like this, in noise measuring with in delay section, by making the simple action of input voltage signal skew n clock (n is integer), the directional property (for example, heart) that can realize accurately being suitable for picking up ambient noise.

For example, when the sample frequency when carrying out analog/digital conversion was 44.1kHz, the distance between centers of the first and second vibrating membranes was about the 7.7mm left and right, and when sample frequency was 16kHz, the distance between centers of the first and second vibrating membranes was about the 21mm left and right.

Figure 27 is the schematic diagram of an example of structure with speech input device of gain adjusting unit.

The differential signal generating unit 720 of the speech input device of present embodiment comprises control portion of gain 910.The control that control portion of gain 910 changes the magnification ratio (gain) in gain section 760.In control portion of gain 910, the difference of vibration signal AD that can export according to the difference of vibration test section, the magnification ratio of ride gain section 760 is dynamically adjusted the balance of the amplitude between the obtained second voltage signal 712-2 of the first obtained voltage signal 712-1 of the first microphone 710-1 and second microphone 710-2 thus.

Differential signal generating unit 720 comprises the first amplitude detection units 920-1.The first amplitude detection units 920-1 detects the amplitude of the output signal S1 of the first delay 732-1 of section, output the first amplitude signal A1.

Differential signal generating unit 720 comprises the second amplitude detection units 920-2.The second amplitude detection units 920-2 detects the amplitude of the output signal S2 of gain section 760, output the second amplitude signal A2.

Differential signal generating unit 720 comprises difference of vibration test section 930.Difference of vibration test section 930 receives the second amplitude signal A2 that the first amplitude signal A1 that the first amplitude detection units 920-1 export and the second amplitude detection units 920-2 export, and obtains output amplitude difference signal AD after the difference of vibration between them.Can come according to difference of vibration signal AD the gain of ride gain section 760, thus FEEDBACK CONTROL be carried out in the gain of gain section 760.

7. the structure of the speech input device of the 4th execution mode

Figure 28, Figure 29 are the schematic diagrames of an example of structure of the speech input device of the 4th execution mode.

The speech input device 700 of the 4th execution mode comprises the first microphone 710-1 with first vibrating membrane.In addition, the speech input device 700 of the 4th execution mode comprises the second microphone 710-2 with second vibrating membrane.

the first vibrating membrane of the first microphone 710-1 and the first vibrating membrane of second microphone 710-2 are configured to the noise intensity ratio less than input voice strength ratio, wherein, described noise intensity is included in the noise composition in differential signal 742 than expression intensity relative inclusion is described first or second voltage signal 712-1, the ratio of the intensity of the described noise composition in 712-2, the intensity relative inclusion that described input voice strength ratio represents to be included in the input phonetic element in described differential signal 742 described first or the second voltage signal in the ratio of intensity of described input phonetic element.

In addition, have the first microphone 710-1 and the second microphone 710-2 with second vibrating membrane of the first vibrating membrane, can have in Fig. 1～structure illustrated in fig. 8.

The speech input device 700 of the 4th execution mode comprises differential signal generating unit 720, the first voltage signal 712-1 that this differential signal generating unit 720 is obtained according to described the first microphone 710-1 and the obtained second voltage signal 712-2 of described second microphone, the differential signal 742 of generation the first voltage signal 712-1 and second voltage signal 712-2.

In addition, differential signal generating unit 720 comprises gain section 760.Gain section 760 amplifies and exports the first obtained voltage signal 712-1 of the first microphone 710-1 with the gain of regulation.

In addition, differential signal generating unit 720 comprises differential signal efferent 740.The first voltage signal S1 and the obtained second voltage signal of described second microphone that differential signal efferent 740 receiving gain sections 760 amplify with the gain of regulation generate and exports with the first voltage signal S1 of the gain amplification of stipulating and the differential signal of second voltage signal.

By amplify the first voltage signal 712-1 (mean and comprise the situation that improves gain and the situation that reduces gain) with the gain of regulation, the difference of vibration that can be with its correction the first voltage signal and second voltage signal is zero, and the noise suppression effect that therefore can prevent differential microphone is because the sensitivity between two microphones that cause because of manufacture deviation etc. is poor and deteriorated.

Figure 30, Figure 31 are the schematic diagrames of an example of structure of the speech input device of the 4th execution mode.

The differential signal generating unit 720 of present embodiment can comprise control portion of gain 910.The control that control portion of gain 910 changes the gain in gain section 760.In control portion of gain 910, can by the gain of ride gain dynamically or statically section 760, adjust the balance of the amplitude between the obtained second voltage signal 712-2 of the gain output S1 of section and described second microphone.

Figure 32 is the schematic diagram of an example of the concrete structure of gain section and control portion of gain.For example, when analog signal is processed, can consist of gain section 760 by analog circuits such as operational amplifiers (op amp) (for example, shown in figure 32 non-upset amplifying circuit).Can perhaps for example during fabrication the value fine setting of resistance R 1, R2 be set as the value of regulation by the value of change resistance R 1, R2, come dynamically or control statically voltage on a terminal that is applied to operational amplifier, the magnification ratio of control algorithm amplifier thus.

Figure 33 A (Figure 33 B) is an example of the structure of the magnification ratio of ride gain section statically.

For example, resistance R 1 or the R2 of Figure 32 comprise the electric resistance array that is connected in series with a plurality of resistance as shown in Figure 33 A, can apply via this electric resistance array the voltage of prescribed level to the terminal (terminal of Figure 32) of the regulation of gain section.Can obtain suitable magnification ratio, and in manufacture process, shear resistive element (r) or the conductor (912 F) that consists of described electric resistance array by laser, perhaps, fuse and consist of resistive element (r) or the conductor (912 F) of described electric resistance array by applying high voltage or high electric current, make described resistance R 1 or R2 take in the resistance value that realizes this magnification ratio.

In addition, for example, also resistance R 1 or the R2 of Figure 32 can be constituted: comprise the electric resistance array that is connected in parallel to as shown in figure 33 a plurality of resistance, and the terminal (terminal of Figure 32) of the regulation of gain section is applied the voltage of prescribed level via this electric resistance array.Can obtain suitable magnification ratio, and in manufacture process, shear resistive element (r) or the conductor (912 F) that consists of described electric resistance array by laser, perhaps, fuse and consist of resistive element (r) or the conductor (912 F) of described electric resistance array by applying high voltage or high electric current, make described resistance R 1 or R2 take in the resistance value that realizes this magnification ratio.

At this, the value that suitable value of magnification is set as the gain balance that can eliminate the microphone that produces in manufacturing process gets final product.By utilizing the electric resistance array that a plurality of resistance are arranged connected in series or in parallel as shown in Figure 33 A (Figure 33 B), can make the resistance value corresponding with the gain balance of the microphone that produces in manufacturing process, thereby can bring into play the function of control portion of gain, this control portion of gain is connected with the terminal of regulation, is used for controlling the gain of described gain section.

In addition, in the above-described embodiment, for example understand the structure that a plurality of resistive elements (r) link together by fuse (F), but be not limited thereto.Also can adopt a plurality of resistance (r) not pass through fuse (F) and direct structure connected in series or in parallel, at this moment, can cut off at least one resistance.

In addition, also can adopt so-called laser trimming to come the structure of adjusting resistance value, for example, as shown in figure 40, be consisted of resistance R 1 or the R2 of Figure 33 by a resistive element, and cut off the structure of the part of resistive element.

Figure 34 is the schematic diagram of an example of structure of the speech input device of the 4th execution mode.

Differential signal generating unit 720 can comprise difference of vibration test section 940.Difference of vibration test section 940 receives the first voltage signal (S1) and the second voltage signal (S2) of the input that becomes differential signal efferent 740, and according to the first voltage signal (S1) that receives and second voltage signal (S2), the first voltage signal (S1) when detecting generation differential signal 742 and the difference of vibration of second voltage signal (S2), and generate and output amplitude difference signal 942 according to testing result.

Control portion of gain 910 is according to difference of vibration signal 942, and the gain in gain section 760 is changed.

Difference of vibration test section 940 can comprise: the first amplitude detecting 920-1 of section, and it is for detection of the amplitude of the output signal of gain section 760; The second amplitude detecting 920-2 of section, it is for detection of the signal amplitude of the obtained second voltage signal of described second microphone; Difference of vibration signal generating unit 930, it obtains the difference of the second amplitude signal 922-2 that the first amplitude signal 922-1 that described the first amplitude detecting 920-1 of section detects and the second amplitude detecting 920-2 of section detect, generating amplitude difference signal 942.

Can be also: output signal S1 and the detected amplitude of the first amplitude detection units 920-1 receiving gain section 760, according to testing result output the first amplitude signal 922-1; The second amplitude detection units 920-2 receives obtained second voltage signal 912-2 and the detected amplitude of second microphone, according to testing result output the second amplitude signal 922-2; The second amplitude signal 922-2 that the first amplitude signal 922-1 that difference of vibration signal generating unit 930 reception the first amplitude detection units 920-1 export and the second amplitude detecting 920-2 of section export also obtains difference, generates and output amplitude difference signal 942.

Control portion of gain 910 receives the difference of vibration signal 942 that difference of vibration signal efferent 930 is exported, outputing gain control signal (for example, rated current) 912.Can pass through the gain that this gain control signal (for example, rated current) 912 comes ride gain section 760, thus FEEDBACK CONTROL be carried out in the gain of gain section 760.

According to present embodiment, can detect in real time and adjust the difference of vibration that changes because of a variety of causes in use.

Described control portion of gain can the output signal S1 of gain section and described second microphone is obtained the difference of vibration of second voltage signal 712-2 (S2) be adjusted into below the ratio value of ratio for regulation of its relative arbitrary signal (S1 or S2).Perhaps, also can adjust the magnification ratio of gain section, obtain the noise suppression effect (for example, approximately more than 10) of regulation.

For example, the difference of vibration of signal S1 and S2 can be adjusted into respect to S1 or S2 be in more than-3% ,+scope below 3% in, also described difference of vibration can be adjusted into be in more than-6% ,+scope below 6% in.In the situation that the former, can be with approximately 10 decibels of noise suppressed, in the latter case, can be with approximately 6 decibels of noise suppressed.

Figure 35, Figure 36, Figure 37 are the schematic diagrames of an example of structure of the speech input device of the 4th execution mode.

Differential signal generating unit 720 can comprise low pass filter section 950.The radio-frequency component of differential signal is removed by low pass filter section 950.Low pass filter section 950 can adopt the filter with single order blocking characteristic.In addition, the cut-off frequency of low pass filter section 950 can be set as 1kHz more than and the arbitrary value K in the following scope of 5kHz.For example, preferably, more than the cut-off frequency of low pass filter section 950 is set as 1.5kHz and the following degree of 2kHz.

Gain section 760 amplifies with the magnification ratio (gain) of stipulating after receiving the first obtained voltage signal 712-1 of the first microphone 710-1, the first voltage signal S1 that output was amplified with the gain of regulation.Differential signal efferent 740 receives the first voltage signal S1 and the obtained second voltage signal S2 of described second microphone 710-2 that amplifies with the gain of regulation by gain section 760, generates and exports with the first voltage signal S1 of the gain amplification of stipulating and the differential signal 742 of second voltage signal.Low pass filter section 950 receives the differential signal 742 that differential signal efferent 740 is exported, and output makes the differential signal 952 of high frequency (frequency of the above frequency band of the K) decay that is included in differential signal 742.

Figure 37 is the key diagram of the gain characteristic of differential microphone.Transverse axis represents frequency, and the longitudinal axis represents gain.1020 mean the curve chart of frequency and the relation between gain of single microphone (single mike).Single microphone has the flat frequency characteristic.1010 speakers that mean at differential microphone imagine the frequency of position and the curve chart of relation between gain, for example, expression from the center of the first microphone 710-1 and second microphone 710-2 at a distance of the frequency characteristic of the position of 50mm.Even the first microphone 710-1 and second microphone 710-2 have the flat frequency characteristic, but due to the high frequency of differential signal from approximately rising with first-order characteristics (20dB/dec) near 1kHz, therefore, the low-pass first order filter of characteristic makes high frequency attenuation if utilization has in contrast, can make the frequency characteristic of differential signal become smooth, thereby can prevent inharmonious sense acoustically.

Therefore, as shown in figure 36, make differential signal by low pass filter to proofread and correct its frequency characteristic, can access thus the almost flat frequency characteristic as shown in 1012.Thus, can prevent that the high frequency of speaker's voice or the high frequency of noise from being emphasized and becoming ear-piercing tonequality.

Figure 38 is the schematic diagram of an example of structure with speech input device of AD converting unit.

The speech input device of present embodiment can comprise an AD converting unit 790-1.The one AD converting unit 790-1 carries out analog/digital conversion to the first obtained voltage signal 712-1 of the first microphone 710-1.

The speech input device of present embodiment can comprise the 2nd AD converting unit 790-2.The 2nd AD converting unit 790-2 carries out analog/digital conversion to the obtained second voltage signal 712-2 of second microphone 710-2.

The speech input device of present embodiment comprises differential signal generating unit 720.Differential signal generating unit 720 can be according to described the first voltage signal 782-1 that converts digital signal by an AD converting unit 790-1 to and the described second voltage signal 782-2 that converts digital signal by described the 2nd AD converting unit 790-2 to, all carry out the gain balance adjustment and postpone balanced adjustment by the Digital Signal Processing computing, generate the differential signal 742 of the first voltage signal and second voltage signal.

At this, differential signal generating unit 720 can have the structure of explanation in Figure 29, Figure 31, Figure 34, Figure 36 etc.

8. the structure of the speech input device of the 5th execution mode

Figure 20 is the schematic diagram of an example of structure of the speech input device of the 5th execution mode.

The speech input device of present embodiment can comprise the sound source section 770 that is arranged on from the first microphone (the first vibrating membrane 711-1) and described second microphone (the second vibrating membrane 711-2) equidistant position.Sound source section 770 can be made of oscillator etc., and sound source section 770 can be set in the central point C2 equidistant position from the second vibrating membrane (film) 711-2 of the central point C1 of the first vibrating membrane (film (diaphragm)) 711-1 of the first microphone 710-1 and second microphone 710-2.

And, can be according to the sound from sound source section 770, will become the phase difference of the first voltage signal S1 of input of differential signal generating unit 740 and second voltage signal S2 or postpone and poorly be adjusted into zero.

In addition, also can carry out the control that the magnification ratio in gain section 760 changed according to the sound from sound source section 770.

And, also can be according to the sound from sound source section 770, will become the first voltage signal S1 of input of differential signal generating unit 740 and the difference of vibration of second voltage signal S2 and be adjusted into zero.

At this, sound source section 770 can use the sound source of the sound that sends single-frequency.For example, can send the sound of 1kHz.

In addition, can be with the frequency setting of sound source section 770 the outer frequency of audio-band.For example, if use the frequency higher than 20kHz (for example, sound 30kHz), people's ear is less than sound.If be the outer frequency of audio-band with the frequency setting of sound source section 770, in the situation that user's also obstacles not when using, can utilize sound source section 770 to adjust the phase difference of input signal or postpone poorly, and sensitivity (gain) is poor.

For example, when consisting of delay section by analog filter, retardation may change according to temperature characterisitic, if but adopt present embodiment, can carry out the delay adjustment corresponding with the environmental change around variations in temperature etc.Postpone to adjust, can often carry out, also can carry out off and on, also can carry out when switching on power etc.

9. the structure of the speech input device of the 6th execution mode

Figure 39 is the schematic diagram of an example of structure of the speech input device of the 6th execution mode.

The speech input device of present embodiment can comprise: the first microphone 710-1, and it has the first vibrating membrane; Second microphone 710-2, it has the second vibrating membrane; And not shown differential signal generating unit, the differential signal of the difference of the second voltage signal that the first voltage signal that described the first microphone of its generation expression is obtained and described second microphone are obtained, at least one vibrating membrane in described the first vibrating membrane and described the second vibrating membrane is obtained sound wave by the sound guide tube 1100 of being arranged to the tubular vertical with face.

Sound guide tube 1100 can be arranged on substrate 1110 around vibrating membrane, so that the sound wave that receives from the peristome 1102 of cylinder does not leak via sound equipment hole 714-2 the vibrating membrane that ground arrives second microphone 710-2 to the outside.Like this, enter the sound of sound guide tube 1100 and arrive the vibrating membrane of second microphone 710-2 in the situation that can not decay.According to present embodiment, by at least one party in described the first vibrating membrane and described the second vibrating membrane, sound guide tube is set, can change the distance till sound arrives vibrating membrane.Therefore, the sound guide tube of suitable length (for example, several millimeters) is set according to the deviation that postpones balance, can eliminates delay thus.

In addition, the present invention is not limited to above-mentioned execution mode, and can carry out various distortion.The present invention includes in fact the structure (for example, function, method and the structure that come to the same thing, perhaps purpose and effect identical structure) identical with the structure that illustrates in execution mode.In addition, the present invention includes the structure that displaces the part of non-intrinsically safe from execution mode in the structure that illustrates.In addition, the structure that the present invention includes the performance action effect identical with the structure that illustrates in execution mode maybe can realize the structure of identical purpose.In addition, present invention resides in the structure that has increased known technology on the basis of the structure that illustrates in execution mode.

Claims (21)

1. speech input device comprises:

The first microphone, it has the first vibrating membrane,

Second microphone, it has the second vibrating membrane,

The differential signal generating unit, the first voltage signal that it is obtained according to described the first microphone and the obtained second voltage signal of described second microphone, the differential signal of generation the first voltage signal and second voltage signal;

This speech input device is characterised in that,

The described first and second vibrating membrane is configured to noise intensity than the structure that is less than input voice strength ratio, wherein, described noise intensity than the intensity that means to be included in the noise composition in described differential signal with respect to be included in described first or the second voltage signal in the ratio of intensity of described noise composition, the intensity that described input voice strength ratio means to be included in the input phonetic element in described differential signal with respect to be included in described first or the second voltage signal in the ratio of intensity of described input phonetic element

Described differential signal generating unit comprises delay section, differential signal efferent and postpones control part,

Described delay section gives after regulation postpones at least one signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, and the signal after regulation postpones has been given in output,

Described differential signal efferent receives have been given by described delay section the signal that postpones and has been used as at least one signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, generate and export the differential signal of the first voltage signal and second voltage signal

Described delay control part is used for controlling the electric current of the retardation of described delay section to the terminal feeding of regulation;

Described delay section makes retardation change according to the electric current that flows through on the terminal of described regulation,

Described delay control part, comprise the electric resistance array that a plurality of resistance are arranged connected in series or in parallel, and cut off the resistive element of the described electric resistance array of formation or the part of conductor, perhaps, comprise at least one resistive element and cut off the part of this resistive element, thus, can change electric current to the terminal feeding of the regulation of delay section.

2. speech input device according to claim 1, is characterized in that,

Electric resistance array or at least one resistive element that a plurality of resistance are arranged connected in series or in parallel of described delay control part, based on the check result of the deviation of the caused delay of individual difference that produces, cut off the resistive element that consists of the electric resistance array that a plurality of resistance are arranged connected in series or in parallel or the part of conductor in described the first microphone and manufacture process described second microphone.

3. speech input device according to claim 1, is characterized in that,

Also comprise:

The one AD converting unit, it carries out analog/digital conversion to described the first voltage signal,

The 2nd AD converting unit, it carries out analog/digital conversion to described second voltage signal,

Described differential signal generating unit basis converts described first voltage signal of digital signal to by a described AD converting unit and converts the described second voltage signal of digital signal by described the 2nd AD converting unit to, generates the differential signal of the second voltage signal of the first voltage signal.

4. speech input device according to claim 3, is characterized in that,

The delay of described delay section is set to the integral multiple of the change-over period of analog/digital conversion.

5. speech input device according to claim 3, is characterized in that,

The distance between centers of the first vibrating membrane and the second vibrating membrane is set to value or its integral multiple that be multiply by gained after velocity of sound the change-over period of analog/digital conversion.

6. speech input device according to claim 1, is characterized in that,

Also comprise gain section, after this gain section gave the regulation gain at least one signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, the signal after the regulation gain had been given in output,

Described differential signal efferent receives by described gain section and has given the signal of gain at least one signal in obtained the first voltage signal of described the first microphone and the obtained second voltage signal of described second microphone, generates and export the differential signal of the first voltage signal and second voltage signal.

7. speech input device according to claim 1, is characterized in that,

Also comprise base portion, be formed with recess on the interarea of this base portion,

Described the first vibrating membrane is arranged on the bottom surface of described recess,

Described the second vibrating membrane is arranged on described interarea.

8. speech input device according to claim 7, is characterized in that,

Described base portion is configured to following structure,

This structure is that the opening that is communicated with described recess is configured in the position than the model sound source of the more close described input voice in formation zone of described the second vibrating membrane on described interarea.

9. speech input device according to claim 8, is characterized in that,

Described recess is more shallow than the interval between the formation zone of described opening and described the second vibrating membrane.

10. speech input device according to claim 7, is characterized in that,

Also comprise base portion, be formed with the first recess and second recess more shallow than described the first recess on the interarea of this base portion,

Described the first vibrating membrane is arranged on the bottom surface of described the first recess,

Described the second vibrating membrane is arranged on the bottom surface of described the second recess.

11. speech input device according to claim 10 is characterized in that,

Described base portion is configured to following structure,

This structure is, the first opening that is communicated with described the first recess is configured in the position than the model sound source of the more close described input voice of the second opening, and wherein, this second opening is communicated with described the second recess.

12. speech input device according to claim 11 is characterized in that,

The difference of the degree of depth of described the first recess and the second recess is less than the interval between described the first opening and the second opening.

13. speech input device according to claim 7 is characterized in that,

Described base portion is configured to make described input voice to arrive simultaneously the structure of the first vibrating membrane and the second vibrating membrane.

14. speech input device according to claim 1 is characterized in that,

The described first and second vibrating membrane is configured to the structure that both normal is parallel to each other.

15. speech input device according to claim 1 is characterized in that,

The normal that the described first and second vibrating membrane is configured to both is the structure on same straight line not.

16. speech input device according to claim 1 is characterized in that,

Described first and second microphone constitute semiconductor device.

17. speech input device according to claim 1 is characterized in that,

The distance between centers of described the first vibrating membrane and the second vibrating membrane is below 5.2mm.

18. an information processing system is characterized in that, comprising:

The described speech input device of any one in claim 1 to 17, and

Dissection process section, it carries out dissection process according to described differential signal to the voice messaging that inputs in described speech input device.

19. an information processing system is characterized in that,

Comprise:

The described speech input device of any one according to claim 1 to 17,

Master computer, it carries out dissection process according to described differential signal to the voice messaging that inputs in described speech input device;

By described communication process section, communicate processing via network and described master computer.

20. the manufacture method of a speech input device, for the manufacture of the speech input device with function of removing the noise composition, this speech input device comprises:

The first microphone, it has the first vibrating membrane,

Second microphone, it has the second vibrating membrane,

The differential signal generating unit, it be used for to generate differential signal, and this differential signal represents the poor of the first voltage signal that described the first microphone is obtained and the obtained second voltage signal of described second microphone;

The manufacture method of this speech input device is characterised in that, comprising:

Prepare the step for the data of the corresponding relation between expression △ r/ λ value and noise intensity ratio, wherein, described △ r/ λ value represents the ratio of the wavelength X of the distance between centers △ r of described the first vibrating membrane and the second vibrating membrane and noise, described noise intensity is included in the described noise composition in described differential signal than expression intensity with respect to be included in described first or the second voltage signal in the ratio of intensity of described noise composition

According to described data, set the step of described △ r/ λ value,

According to the described △ r/ λ value that sets and the wavelength of described noise, set the step of described distance between centers,

Postpone to set step, in this postpones to set step, make the delay control part comprise the electric resistance array that a plurality of resistance are arranged connected in series or in parallel, wherein, described delay control part is used for controlling the electric current of the retardation of described delay section to the terminal feeding of the regulation of delay section, the retardation of described delay section changes according to the electric current that flows through on the terminal of described regulation, and, described delay control part is for the electric current to the terminal feeding regulation of the regulation of delay section, cuts off the resistive element that consists of described electric resistance array or the part of conductor.

21. the manufacture method of speech input device according to claim 20 is characterized in that,

Set in step in described delay,

From described the first microphone and described second microphone equidistant position, sound source is being set,

According to the sound from described sound source section, judge the phase difference of the voltage signal that the first microphone and described second microphone are obtained, and cut off the resistive element of the described electric resistance array of formation or the part of conductor, thereby realize making this phase difference resistance value within the limits prescribed.

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