CN102405634A - Speakerphone apparatus - Google Patents
Speakerphone apparatus Download PDFInfo
- Publication number
- CN102405634A CN102405634A CN201080017260XA CN201080017260A CN102405634A CN 102405634 A CN102405634 A CN 102405634A CN 201080017260X A CN201080017260X A CN 201080017260XA CN 201080017260 A CN201080017260 A CN 201080017260A CN 102405634 A CN102405634 A CN 102405634A
- Authority
- CN
- China
- Prior art keywords
- echo
- attenuation
- speaker
- transmission signal
- signal path
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000004891 communication Methods 0.000 claims abstract description 137
- 230000005540 biological transmission Effects 0.000 claims abstract description 70
- 238000003780 insertion Methods 0.000 claims abstract description 39
- 230000037431 insertion Effects 0.000 claims abstract description 39
- 238000001514 detection method Methods 0.000 claims description 52
- 239000002699 waste material Substances 0.000 claims description 52
- 230000009977 dual effect Effects 0.000 claims description 43
- 238000012545 processing Methods 0.000 claims description 10
- 230000008878 coupling Effects 0.000 claims description 4
- 238000010168 coupling process Methods 0.000 claims description 4
- 238000005859 coupling reaction Methods 0.000 claims description 4
- 230000009467 reduction Effects 0.000 claims description 4
- 230000008859 change Effects 0.000 description 9
- 238000010586 diagram Methods 0.000 description 7
- 230000035807 sensation Effects 0.000 description 7
- 238000005070 sampling Methods 0.000 description 5
- 230000005764 inhibitory process Effects 0.000 description 4
- 238000012544 monitoring process Methods 0.000 description 4
- 230000004044 response Effects 0.000 description 4
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000007704 transition Effects 0.000 description 3
- 230000002238 attenuated effect Effects 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- 230000003111 delayed effect Effects 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000001629 suppression Effects 0.000 description 2
- 230000001052 transient effect Effects 0.000 description 2
- 244000287680 Garcinia dulcis Species 0.000 description 1
- 230000003044 adaptive effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000000452 restraining effect Effects 0.000 description 1
- 235000015170 shellfish Nutrition 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Images
Landscapes
- Telephone Function (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Abstract
A speakerphone apparatus includes a microphone and a speaker, a voice switch; an echo canceller, a doubletalk detector, and an echo suppressor. The voice switch includes a transmission side loss insertion unit, a reception side loss insertion unit, and an insertion loss amount control unit, and the insertion loss amount control unit includes a total loss amount calculator and an insertion loss amount allocation processor. Further, the total loss amount calculator has an update mode in which a total sum of the loss amounts inserted in the respective paths is calculated and adaptively updated based on estimations of each feedback gain, and a fixed mode in which a total loss amount is fixed to a initial value, and operates in the fixed mode while the echo canceller does not sufficiently converge after starting communications and in the update mode after the echo canceller fully converges.
Description
Technical field
The present invention relates to a kind of speaker-phone device that is used for dwelling house or office.
Background technology
Known a kind of speaker-phone device on the prior art, it need not to listen the hands-free communication of cylinder device when having reached communication in the following manner: use loud speaker that voice signal is amplified, and it is exported to apart from communication terminal MPTY far away; And use microphone to collect the voice of MPTY, and voice are sent to his/her the other side's communication terminal.Here, the voice signal that loud speaker will send from the other side's communication terminal amplifies, and microphone is collected the voice that send from MPTY.
In this speaker-phone device, can be coupled through the acoustics between microphone and the loud speaker and set up acoustic feedback path, warp path thus may be heard the echo (acoustic echo) of making us uncomfortable.In addition, if in communication system, under a frequency component, form closed-loop via said feedback path, and whistle (howling) then may take place above 1 in the gain of said closed-loop under said frequency.Therefore, a kind of Echo Canceller (echo canceller) and voice switch (voice switch) are provided, so that prevent echo and the whistle that makes us uncomfortable.
Said voice switch is constantly assessed communications status (transmit status, accepting state), and through coming suitably to distribute loss based on assessment result loss is provided to sending signal path and receiving in the signal path.Said Echo Canceller comprises: sef-adapting filter (adaptive filter) is used for discerning the impulse response of feedback path, and comes doubtful (suspected) echo components in the estimation feedback path according to the signal that inputs to sef-adapting filter; And subtracter, be used for deducting estimated echo components from the signal that inputs to subtracter via feedback path.Generally speaking, said sef-adapting filter needs some seconds learning time, so that the impulse response of identification feedback path.Therefore, in the some seconds after following the communication beginning closely, can't suppress echo effectively.Yet,, wherein may make us uncomfortable echo or whistle owing in communication system, set up closed-loop.
In this regard, existing people proposes a kind ofly can follow the inhibition of communication beginning back closely and make us the speaker-phone device (for example seeing also the open No.2002-359580 of Japanese patent application) that uncomfortable echo or whistle take place.
In this existing instance; Though not convergence immediately after the communication beginning of Echo Canceller; But the voice switch is operated under fixed mode, and the total amount of the loss that wherein in signal path, provides (total losses amount) is fixed in enough big initial value, suppresses the echo or the whistle that make us uncomfortable thus.On the other hand, after Echo Canceller was restrained fully, the voice switch was upgrading the mode work, wherein needed by occasion and renewal total losses amount, and therefore can reach full duplex (full duplex) and communicate by letter.
Simultaneously, if combine digital communication between a plurality of speaker-phone devices (for example Internet Protocol (IP) communication etc.), then may be in speech data sends because of packet transaction or the communication buffer that is used for suppressing shake (jitter) handle and postpone.Generally speaking, known when in the speech data between a plurality of speaker-phone devices sends, taking place to postpone, the Along with delayed time is elongated, during communication the speaker to the tolerance variation of echo, even and if therefore small echo also can make the speaker not feel well.
Through under fixed mode, setting the initial value bigger, can prevent the echo of making us uncomfortable here than the initial value of existing analog communication.Yet, the amount of degradation of echo tolerance (tolerance) may exceedance shellfish very, this more can't covered by the amount of suppression of Echo Canceller under the new model, and therefore can only in half-duplex operation, communicate by letter but not in full-duplex communication, communicate by letter.In addition, when ambient noise level is higher, following problem may take place: the only side joint that the voice switch continues in transmitter side and receiver side is logical, and therefore makes the voice from a said side not be sent to opposite side.
On the other hand; When (for example communicating by letter in combine digital between speaker-phone device and the communicator that uses receiver; IP communication etc.) time; Can make the residual echo decay that takes place in the transmission signal path of speaker-phone device through the echo suppressor (echo suppressor) that wherein is equipped with, reach full-duplex communication thus.Yet if the signal that is sent to the other side's communicator from the speaker-phone device, there is the noise of high level, echo suppressor not only makes the residual echo decay, but also can make noise attentuation momently.This of short duration decay to noise is postponed, and is discovered by the other side via receiver.Therefore, use the other side of receiver to feel the disconnection sensation of making us uncomfortable in communication period.
In addition, if the other side uses receiver, prevent that disconnection mentioned above from feeling then can be when the attenuation of echo suppressor being set to such an extent that use the speaker-phone device also for a short time than the other side.Yet, have the shortcoming of hearing residual echo via receiver in the case.
Summary of the invention
In view of preceding text, the present invention provides a kind of speaker-phone device, even it also can reach full-duplex communication when in being sent to the other side's voice, transmission lag taking place, even and when the other side uses receiver, also can prevent to feel the sensation of disconnection via receiver.
According to an aspect of the present invention, a kind of speaker-phone device is provided, it comprises: microphone and loud speaker; The voice switch; In order between sending under the communications status and receiving, to switch in the following manner: in receiver side signal path and transmission signal path, loss is provided; Reception signal from the other side's communication terminal is sent to said loud speaker via the receiver side signal path, and the transmission signal of being collected by microphone is sent to the other side's communication terminal via said transmission signal path; Echo Canceller is used to suppress the acoustics coupling between microphone and the loud speaker and the acoustic echo that causes; And the double talk detection device, be used to detect dual end communication.
Said voice switch comprises and is used for providing the transmitter side loss of loss to insert the unit at the transmission signal path; Be used for providing the receiver side loss of loss to insert the unit at the receiver side signal path; And the insertion waste control unit that is used for being controlled at the corresponding waste that transmitter side and receiver side provide.
In addition; Said insertion waste control unit comprises: total losses amount calculator; Its lead-out terminal from said receiver side loss insertion unit in order to estimated path feeds back to the acoustic feedback gain that the input terminal of unit is inserted in said transmitter side loss via acoustic echo path, and calculates the summation that provides to the waste of feedback path based on the estimation that said acoustic feedback is gained; And insertion waste distribution processor; It is in order to monitor said transmission signal and said reception signal to estimate communications status; And reach the summation of calculating by total losses amount calculator based on the communications status of estimating, and confirm to distribute to the corresponding insertion waste that unit and receiver side loss insertion unit are inserted in the transmitter side loss.
In addition; Total losses amount calculator has renewal pattern and fixed mode, in new model more, through based on the corresponding estimation of feedback oscillator is calculated the total losses amount that in feedback path, provides and upgraded the total losses amount adaptively; And in fixed mode, the total losses amount is fixed in initial value.Therefore, when Echo Canceller was not fully restrained after the communication beginning, total losses amount calculator was operated with fixed mode, and after Echo Canceller was restrained fully, total losses amount calculator was with more new model operation.
Said speaker-phone device also comprises echo suppressor, echo suppressor in order to through combining voice switch and/or double talk detection device so that in sending signal path, provide the particular decay amount to make the residual echo decay.
Through above configuration, even if in the voice that between a plurality of communicators, send transmission lag takes place, echo suppressor also makes the residual echo decay that in sending signal path, takes place because of transmission lag effectively, reaches full-duplex communication thus.
Estimate that the voice switch is in accepting state if insert the waste distribution processor, then echo suppressor can insert the particular decay amount in sending signal path, otherwise does not insert the particular decay amount.
Therefore, the inflection that can suppress to take place in the voice (inflection), and after communication, only make the echo attenuation of making us uncomfortable.Therefore, can reach pleasant communication.
When the double talk detection device was just detecting dual end communication, echo suppressor can not insert attenuation in sending signal path, otherwise inserted attenuation.
Therefore, can make because the inflection that the error fade of the voice that be about to send is taken place in voice is suppressed, and when communication, the echo of making us uncomfortable decayed.Therefore, can reach pleasant communication.
If the double talk detection device does not detect dual end communication and inserts the waste distribution processor and estimate that the voice switch is in accepting state, then echo suppressor can insert above-mentioned particular decay amount in sending signal path.
Through operation like this, can prevent that echo suppressor from not providing attenuation by error and making us uncomfortable residual echo; And therefore the echo of making us uncomfortable is decayed in communication period.
Preferably, when Echo Canceller is not fully restrained, only estimate that in insertion waste distribution processor the voice switch is under the situation of accepting state after the communication beginning, echo suppressor just inserts above-mentioned particular decay amount in sending signal path.
Generally speaking, when Echo Canceller was not fully restrained, the double talk detection device can't detect dual end communication.Therefore; Estimate that the voice switch is in accepting state if insert the waste distribution processor; Then how no matter echo suppressor all insert above-mentioned particular decay amount from the testing result of double talk detection device in sending signal path, thereby begin when the back Echo Canceller is not fully restrained the echo of making us uncomfortable to be decayed in communication.
When echo suppressor is sending in the signal path when inserting above-mentioned particular decay amount; Estimate that the voice switch is not in accepting state or the double talk detection device detects dual end communication if insert the waste distribution processor, then echo suppressor can stop attenuation being inserted in the transmission signal path immediately.
Through operation like this, can prevent inflection to be taken place the error fade of sending signal in voice because of echo suppressor.
Echo Canceller also can comprise: sef-adapting filter is used for discerning adaptively the characteristic of echo path; Subtracter is used for deducting near end signal the output of sef-adapting filter; And the double talk detection device, be used to detect dual end communication.In addition, when the double talk detection device detected dual end communication, Echo Canceller can not upgrade the coefficient of sef-adapting filter.
Through this configuration, can use the double talk detection device that provides in the Echo Canceller to reach the simplification of configuration and the reduction of cost.
Preferably, in sending signal path, carry out the handled in Echo Canceller, voice switch and the echo suppressor in order.
Through this configuration, because echo suppressor is placed in voice switch back in sending signal path, so, also can prevent in the voice switch inflection to take place, thereby reach pleasant communication environment even echo suppressor makes transmission signal attenuation by error.
Echo suppressor can gain based on the acoustic feedback of being estimated by total losses amount calculator and adjust attenuation.
Through this configuration,, also can suppress the generation of voice inflection even the voice that send from the near-end loud speaker are decayed by echo suppressor by error.
Echo suppressor can be adjusted attenuation based on the signal level mean value that receives signal.
Through this configuration,, also can suppress the generation of voice inflection even the voice that send from the near-end loud speaker are decayed by echo suppressor by error.
When the signal level that receives signal is lower than threshold value; Echo suppressor can be fixed as standard value with sending the attenuation of inserting in the signal path; And when the signal level that receives signal is a threshold value or when higher, echo suppressor is being adjusted attenuation in the scope of the upper limit to the standard value that is higher than standard value.
Through this configuration, can suppress the generation of voice inflection.
Echo Canceller also can comprise: (signal level average, SLA) arithmetic element are used to calculate the signal level mean value that receives signal to signal level mean value; Sef-adapting filter is used for discerning adaptively the characteristic of echo path; And subtracter, be used for deducting the output of sef-adapting filter near end signal.In addition, echo suppressor can be adjusted attenuation based on the signal level mean value that is calculated by signal level mean value arithmetic element.
This makes can reach the simplification of configuration and the reduction of cost.
Only do not detect dual end communication and insert waste distribution processor estimation voice switch and be under the situation of accepting state at the double talk detection device; Echo suppressor can insert the particular decay amount in sending signal path; And when inserting the waste distribution processor and estimate that the voice switch neither is in accepting state and is not in transmit status again; Maybe when inserting the waste distribution processor and estimate that the voice switch is in accepting state and double talk detection device and detects dual end communication, echo suppressor reduces the attenuation of inserting in this transmission signal path monotonously.
Through this configuration, even if in the voice of the communicator that is sent to the other side, transmission lag takes place, echo suppressor also can make effectively and send the residual echo decay that takes place because of transmission lag in the signal path, reaches full-duplex communication thus.In addition, when not from the speaker-phone device when the communicator that uses receiver sends signal, echo suppressor reduces the attenuation of inserting in the transmission signal path monotonously.This makes the disconnection sensation that the speaker at the communicator place can prevent to use receiver is not felt well by temporary transient decay because of ambient noise.
When the communications status of when attenuation reduces just monotonously, being estimated by insertion waste distribution processor became transmit status, echo suppressor can make attenuation be reduced to zero immediately.
Through operation like this, can prevent is decayed by error by echo suppressor and prevent from the voice (transmission voice) that the near-end loud speaker sends the voice that the other side's loud speaker hears inflection takes place.
When the attenuation of in sending signal path, inserting reduces just monotonously; Then do not detect dual end communication and when inserting communications status that the waste distribution processor estimates and be accepting state, echo suppressor can insert the particular decay amount once more in sending signal path when the double talk detection device.
Through this configuration, can prevent that echo suppressor from not providing attenuation by error and making us uncomfortable residual echo; And the echo of making us uncomfortable is decayed in communication period.
When by inserting communications status that the waste distribution processor estimates neither accepting state when being not transmit status again; Or when communications status be accepting state and double talk detection device when detecting dual end communication, the reduction ratio that echo suppressor can be constant reduces the attenuation of in sending signal path, inserting.
In the case, for example, when reducing with mode progressively when comparing, attenuation was reduced to for zero required time period (changing (transition) time period) and can shortens relatively.
When the double talk detection device does not detect dual end communication and when inserting communications status that the waste distribution processor estimates and be accepting state; Echo suppressor can insert the particular decay amount in sending signal path; The level of the ambient noise that echo suppressor is estimated to superpose in this transmissions signal, and when ambient noise level uprises, reduce the attenuation of inserting in this transmission signal path based on the ambient noise level of estimation.
Through this configuration, even if in the voice of the communicator that is sent to the other side, transmission lag takes place, echo suppressor also can make effectively and send the residual echo decay that takes place because of transmission lag in the signal path, reaches full-duplex communication thus.In addition, owing to uprise with noise level, echo suppressor makes and sends the attenuation of inserting in the signal path and reduce, thus can suppress the instantaneous decay of noise, thereby make and be difficult to feel the sensation of breaking off.In the case, if echo suppressor reduces attenuation, then the attenuating of residual echo reduces.Yet when reality was used, residual echo was hidden by ambient noise, and in communication, can not cause trouble.
The echo amount that echo suppressor can be estimated according to received signal level with compare according to the attenuation of sending the ambient noise level that superposes in the signal, and in sending signal path, insert less one of numerical value in echo amount and the attenuation.
This makes and can make the residual echo decay fully, and prevents to sense the sensation of disconnection simultaneously.
When ambient noise level exceeded particular level, echo suppressor can be adjusted into steady state value with attenuation based on noise level.
Through this configuration, can prevent when ambient noise level is very high that residual echo from not obtaining decay.
Description of drawings
Through the description of preferred embodiments that provides below in conjunction with accompanying drawing, target of the present invention and characteristic will become obviously, wherein:
Fig. 1 shows the block diagram according to the first embodiment of the present invention;
Fig. 2 has presented the flow chart of the operation that is used to explain voice switch shown in Figure 1;
Fig. 3 representes to be used to explain the flow chart of the operation of echo suppressor shown in Figure 1;
Fig. 4 shows block diagram according to a second embodiment of the present invention;
Fig. 5 is the flow chart that is used to explain echo suppressor shown in Figure 4;
Fig. 6 shows the block diagram of a third embodiment in accordance with the invention;
Fig. 7 has presented the flow chart of the operation that is used to explain echo suppressor illustrated in fig. 6;
Fig. 8 is the flow chart of operation of echo suppressor that is used for explaining the modification instance of the 3rd embodiment;
Fig. 9 shows the block diagram of a fourth embodiment in accordance with the invention;
Figure 10 shows the flow chart of the operation of the echo suppressor that is used for explaining the 4th embodiment;
Figure 11 has presented the flow chart of the operation that is used for explaining echo suppressor according to a fifth embodiment of the invention;
Figure 12 shows the attenuation of echo suppressor time to time change in the fifth embodiment of the present invention;
Figure 13 representes to be used for explaining the flow chart of the operation of echo suppressor according to a sixth embodiment of the invention;
Figure 14 is the flow chart of operation that is used for explaining the echo suppressor of the 6th embodiment; And
Figure 15 shows the attenuation of echo suppressor time to time change among the 6th embodiment.
Embodiment
Hereinafter, will illustrate in greater detail embodiments of the invention with reference to accompanying drawing, accompanying drawing forms the part of this paper.
First embodiment
With reference to figure 1, the speaker-phone device of present embodiment comprises: microphone 1; Loud speaker 2; Voice switch 10; Voice switch 10 is through inserting loss and change between in communications status, sending and receiving in receiving signal path (being illustrated by dotted line A among Fig. 1) and transmission signal path (being illustrated by dotted line B among Fig. 1); Reception signal from the other side's communication terminal is sent to loud speaker 2 via receiving signal path, and the transmission signal of being collected by microphone 1 is sent to the other side's communication terminal via sending signal path; Echo Canceller 20, the acoustic echo that its inhibition is caused by the coupling of the acoustics between microphone 1 and the loud speaker 2; And amplifier of microphone G1, be used to amplify the output signal (transmission signal) of microphone 1; Speaker amplifier G2 is used to amplify the input signal (reception signal) of microphone 2.
In addition, said speaker-phone device comprises: amplifier G3 is used for being adjusted at the transmission signal path and is inserted in the traffic volume between Echo Canceller 20 and the voice switch 10; And echo suppressor 30, it is through inserting the particular decay amount remaining echo of decaying in sending signal path.
Said Echo Canceller 20 has well-known sef-adapting filter 21 and subtracter 22.Echo Canceller 20 is discerned the impulse response of feedback path (acoustic echo path) Hac that is formed by the acoustics between loud speaker 2 and the microphone 1 coupling adaptively through sef-adapting filter 21, and suppresses the echo components (acoustic echo) estimated according to reference signal (to the input signal of speaker amplifier G2) through the acoustic echo that from the output signal of amplifier of microphone G1, deducts estimation with subtracter 22.
In addition; Insert waste controller 13 and comprise insertion waste (ILA) distribution processor 15; It sends signal and receive signal through monitoring estimates communications status, and confirms the distribution to the corresponding insertion waste of sending signal attenuator 11 and receiving signal attenuation device 12 based on the total losses amount of communications status of estimating and calculating.
In addition, can pass through control hardware (for example, digital signal processor (DSP)), realize Echo Canceller 20 and voice switch 10 through software (program that for example, is used for Echo Canceller and voice switch).Therefore, by unshowned A/D converter (analog-to-digital converter) with the particular sample cycle to inputing to voice switch 10 and Echo Canceller 20 and sampling and quantize from the signal (send signal and receive signal) of its output.
Total losses amount calculator 14 estimates to input to signal that sends signal attenuator 11 and the corresponding average power of signal short cycle of exporting from receiving signal attenuation device 12 through using rectifier, low pass filter to wait.The average power of the output signal of attenuator 12 estimation to received signal under the maximum delay time that total losses amount calculator 14 also obtains in acoustic echo path Hac, to expect.Subsequently; Total losses amount calculator 14 will be set a value for to the estimation α ' of acoustic feedback gain, and said value obtains in the following manner: estimate divided by the average power of the input signal that sends signal attenuator 11 with the average power of the output signal of attenuator 12 estimation to received signal under the maximum delay time.
In addition, total losses amount calculator 14 calculates total losses amount Lt through using to the estimation α ' of acoustic feedback gain and required gain margin (gain margin) MG, and exports total losses amount Lt to insertion waste distribution processor 15.
Insert the corresponding input/output signal that signal attenuator 11 and receiving signal attenuation device 12 are sent in 15 monitorings of waste distribution processor, and confirm communications status (accepting state, transmit status) based on the existence of magnitude relationship in the power level of these input/output signals and voice signal.In addition, insert the insertion waste of waste distribution processor 15 adjustment respective attenuation devices 11 and 12, send signal attenuator 11 and receiving signal attenuation device 12 so that can be dispensed to pro rata based on determined communications status and with total losses amount Lt.
In the present embodiment; Total losses amount calculator 14 has more new model and fixed mode, in new model more, calculates and upgrade adaptively the summation of the waste that is inserted into based on the estimation α ' to the acoustic feedback gain; In fixed mode, the total losses amount is fixed in an initial value.Before Echo Canceller 20 was restrained fully, total losses amount calculator 14 was operated in fixed mode after the communication beginning, and subsequently, after Echo Canceller was restrained fully, total losses amount calculator 14 was more being operated in the new model.
Also be; In case in the special time period after the communication beginning (for example; Hundreds of millisecond or more of a specified duration) value of the estimation α ' of acoustic feedback gain remains on (for example, the value of the little 10dB to 15dB of estimation α ' during than the communication beginning) below the threshold epsilon, and total losses amount calculator 14 thinks that just Echo Canceller 20 fully restrains; And switch to after this and more operating in the new model, and it is operated in fixed mode before this moment always.In addition, in fixed mode, initial value is set to fully the value of the total losses amount of upgrading greater than needing by occasion in the new model more.
Therefore; Though Echo Canceller 20 is not fully convergence immediately after the communication beginning; But total losses amount calculator 14 is operated in fixed mode; And set the total losses amount for initial value, and therefore can inhibition make us the echo (acoustic echo) of discomfort or the generation of whistle, and reach stable half-duplex operation with fully big value.
In addition; When Echo Canceller 20 when after the communication time started, restraining fully after through the reasonable time; The operator scheme of total losses amount calculator 14 changes over more new model from fixed mode; And the total losses amount that is inserted into is reduced to the value that fully is lower than initial value, and therefore can reach full-duplex communication.
Hereinafter, will explain the concrete operations of total losses amount calculator 14 in new model more with reference to figure 2.
The particular sample of total losses amount calculator 14 change over the time point of new model more from fixed mode after carried out in the time period estimation of acoustic feedback gain handled, and calculates the estimation α ' (step 1) to the acoustic feedback gain.According to estimating α ' and gain margin MG, calculate required total losses amount Lr (n) (step 2) through using following formula, so that can keep the gain margin MG [dB] of closed-loop:
Lr(n)＝20log|α′(n)|+MG[dB]
Here, α ' (n) and Lr (n) be respectively to the estimation α ' of acoustic feedback gain and required total losses amount, it is to change over the n time sampling calculating that time of new model more lights by fixed mode.In addition, when required total losses amount Lr (n) greater than confirming in (n-1) inferior sampling place and during the actual previous total losses amount Lt (n-1) that inserts, total losses amount calculator 14 is added into previous total losses amount Lt (n-1) (step 3 and 4) with fractional increments Δ i [dB].Also promptly, total losses amount calculator 14 is set total losses amount Lt (n) for Lt (n-1)+Δ i.
In addition, as desired total losses amount Lr (n) during less than previous total losses amount Lt (n-1), total losses amount calculator 14 deducts small decrement d [dB] from previous total losses amount Lt (n-1), and sets the total losses amount result's (step 5 and 6) of said subtraction for.Also promptly, Lt (n)=Lt (n-1)-Δ d.
As stated; Because total losses amount calculator 14 makes the total losses amount increase respectively and reduces small value Δ i and Δ d, even make us uncomfortable feeling in the process that therefore (just as just beginning the back of communicate by letter with the other side's communication terminal) also can be eliminated tin when the acoustic feedback gain is being upgraded a coefficient (filter coefficient) versatilely because of Echo Canceller 20 and fluctuateed widely with convergence.
Said like preceding text about existing instance, if between a plurality of speaker-phone devices, carry out digital communication such as IP communication, then because of packet transaction or the communication buffer that is used to suppress to shake handle, may in voice data transmission, postpone.Generally speaking; Known the quantitative change of Along with delayed time is long when taking place to postpone in the voice data transmission between a plurality of speaker-phone devices, and the speaker is to the tolerance variation of echo during communication; And therefore the speaker perceives even a kind of small echo, thereby does not feel well.Through setting the initial value bigger, can prevent the echo of making us uncomfortable here than the initial value of existing instance to fixed mode.
Yet the amount of degradation of echo tolerance may reach tens of decibels sometimes, and this more can't covered by the amount of suppression of Echo Canceller under the new model fully.In the case, in half-duplex but not executive communication under the full duplex.In addition, when noise level is higher, following problem may take place: wherein the voice switch continues that only a side joint is logical in transmitter side and receiver side, and therefore, is not sent to opposite side from the voice of a side.
In this regard, in the present embodiment, in sending signal path, echo suppressor 30 is provided extraly in Echo Canceller 20 and voice switch 10 back.Echo suppressor 30 makes acoustic echo (hereinafter, being called " the residual echo ") decay that should have been suppressed by Echo Canceller 20.Echo suppressor 30 need make the residual echo decay effectively sending voice signal (transmission signal) when not adding decay.
In addition; When voice switch 10 is in transmit status; Echo suppressor 30 think have no residual echo wait to eliminate or any voice signal (transmission signal) to be sent, and will not add damply output (step 13) in statu quo from the signal of voice switch 10 input.
Through according to the first embodiment of the present invention, even if in the voice that between a plurality of communicators, send transmission lag takes place, echo suppressor also makes effectively and sends the residual echo decay that takes place because of transmission lag in the signal path, reaches full-duplex communication thus.
This point; For example be in transmit status when echo suppressor 30 at voice switch 10 but not sending during accepting state when inserting an attenuation in the signal path; Decayed from the voice that the speaker of proximal lateral (in the present embodiment for using the speaker of speaker-phone device communication) sends; This is undesirable, and may be heard and as the voice inflection by the speaker at the other side's communicator place, wherein the volume step-down of voice or uprise.Yet; In the present embodiment, when voice switch 10 was in accepting state, echo suppressor 30 inserted an attenuation in sending signal path; And when voice switch 10 was in transmit status, echo suppressor 30 did not insert attenuation in sending signal path.Therefore, can only make echo (residual echo) decay of making us uncomfortable, and the voice inflection can not take place.
In addition, if echo suppressor 30 is placed in and sends in the signal path in voice switch 10 fronts and make transmission signal attenuation by error, then decayed by error by echo suppressor 30 the voice inflection possibly take place in voice switch 10 because of sending signal.Yet; In the present embodiment; Because echo suppressor 30 is to be configured in Echo Canceller 20 and voice switch 10 back in sending signal path; And corresponding processing is carried out in order, so even if echo suppressor 30 makes transmission signal attenuation by error, also can in voice switch 10, suppress the generation of voice inflection.Therefore, can be communication pleasant environment is provided.
Simultaneously, the inventor has proposed a kind of speaker-phone device, wherein in sending signal path, is provided for inserting the attenuator (seeing the open No.2003-324371 of Japanese patent application) of loss at the back at the voice switch.Yet, in this file, only estimate in special time period, to remain on a threshold value when following at the temporary transient power that sends signal, attenuator just inserts the loss of specified quantitative in sending signal path.Therefore, if echo having is higher than the big volume of said threshold value, then attenuator does not insert loss, and the echo of making us uncomfortable possibly be sent to the other side.
In addition, even if the power level of the voice that send from the speaker of proximal lateral is lower than said threshold value, attenuator also possibly all of a sudden make the voice signal decay because of inserting loss.Yet in the speaker-phone device according to embodiment, echo suppressor 30 is operated to combine voice switch 10 and is inserted an attenuation, prevents that thus above situation from taking place.
Second embodiment
Fig. 4 schematically shows the block diagram of speaker-phone device according to a second embodiment of the present invention.The speaker-phone device of second embodiment is different from the speaker-phone device of first embodiment, in sending signal path, an attenuation is provided because echo suppressor 30 combines Echo Cancellers 20, and others are identical with aspect among first embodiment.Therefore, same components is represented by same numeral, and will be omitted the explanation to it.
In this embodiment, except sef-adapting filter 21 and subtracter 22, Echo Canceller 20 comprises double talk detection device 23.Double talk detection device 23 disturbs convergence based on the signal whether signal from amplifier of microphone G1 output comprises a certain level of sef-adapting filter 21; Detect dual end communication; That is near-end speaker and the far-end speaker state to speaking each other in fact simultaneously.When double talk detection device 23 detected dual end communication, sef-adapting filter 21 did not upgrade filter coefficient, and kept previous value.
Next, will explain the operation of echo suppressor 30 with reference to flow chart shown in Figure 5.Echo suppressor 30 continues the double talk detection device 23 (step 21) of monitoring Echo Canceller 20.When double talk detection device 23 does not detect dual end communication; Echo suppressor 30 is confirmed to exist residual echo to be eliminated or is sent no voice signal to be sent in the signal path, and through making input signal and particular decay multiplication make its decay and with its output (step 22).
In addition, when double talk detection device 23 detected dual end communication, echo suppressor 30 confirmed to exist voice signal to be sent, and through not making input signal and particular decay multiplication input signal was not added output (step 23) damply.
Through second embodiment, even if in the voice that between a plurality of communicators, send transmission lag takes place, echo suppressor also can make effectively and send the residual echo decay that takes place because of transmission lag in the signal path, reaches full-duplex communication thus.
In this embodiment; When double talk detection device 23 is detecting dual end communication; Echo suppressor 30 does not insert attenuation in sending signal path, and when double talk detection device 23 did not detect dual end communication, echo suppressor 30 inserted attenuation in sending signal path.Therefore, can prevent to be decayed by error, and prevent to take place in the voice inflection from the voice that the speaker of proximal lateral sends.In addition, owing to when communication, can make the echo attenuation of making us uncomfortable, pleasant environment is provided so can be communication.
In addition; Owing to can use the double talk detection module (double talk detection device 23) that provides in the Echo Canceller 20 in this embodiment; So the simplification that can reach configuration (for example; Lower standard in the minimizing of the procedure quantity of in DSP, carrying out, the DSP, be used for minimizing of stored program ROM capacity or the like), and the minimizing of reaching cost.
The 3rd embodiment
Fig. 6 shows the block diagram of the speaker-phone device of a third embodiment in accordance with the invention.The basic configuration of present embodiment is identical with first embodiment and second embodiment, and difference is, echo suppressor 30 combine voice switchs 10 and Echo Canceller 20 both and in sending signal path, insert an attenuation.Therefore, same components is represented by same numeral, and will be omitted the explanation to it.
Hereinafter, will explain the operation of echo suppressor 30 with reference to figure 7.Echo suppressor 30 is monitored the state (step 31) of voice switch 10 always, and when voice switch 10 was in accepting state, echo suppressor 30 confirmed whether double talk detection device 23 detects dual end communication (step 32).When the double talk detection device did not detect dual end communication, echo suppressor 30 thought and has residual echo to be eliminated or do not have voice signal to be sent, and through making input signal and particular decay multiplication make its decay with its output (step 33).
When voice switch 10 is not in accepting state; Or when voice switch 10 is in accepting state when double talk detection device 23 detects dual end communication; Echo suppressor 30 is confirmed no residual echo or is not had voice signal to be sent, and input signal is not added damply output (step 34) in statu quo.
Through this embodiment, can prevent to be decayed by error, and prevent to take place in the voice inflection from the voice that the speaker of proximal lateral sends.In addition, echo suppressor 30 can only make the echo attenuation of making us uncomfortable, and does not make us uncomfortable residual echo (this is because echo suppressor 30 does not all of a sudden insert attenuation), is provided for the pleasant environment of communicating by letter thus.
Here, echo suppressor 30 can be adjusted the attenuation of inserting in this transmission signal path based on the estimation α ' of acoustic feedback gain, and the estimation α ' of acoustic feedback gain is estimated by total losses amount calculator 14.Next, will describe with reference to the operation of 8 pairs of echo suppressors 30 of figure when echo suppressor 30 is adjusted the attenuation of inserting in these transmission signal paths.
On the other hand, when voice switch 10 was in accepting state and double talk detection device 23 and does not detect dual end communication, echo suppressor 30 was set an attenuation coefficient, said attenuation coefficient and input signal multiply by mutually reach standard value SUP_MIN (step 43).After this; The summation of estimating when voice switch 10 to the estimation α ' of acoustic feedback gain and total losses amount Lt (n) is threshold value TH or more greatly when (step 44), then echo suppressor 30 is changed into the upper limit SUP_MAX (step 45) greater than this standard value with attenuation coefficient from standard value SUP_MIN.
In addition, when voice switch 10 estimate to the summation of the estimation α ' of acoustic feedback gain and total losses amount Lt (n) during less than threshold value TH (step 44), echo suppressor 30 is not kept standard value SUP_MIN with as attenuation coefficient with not adding change.At last, multiply each other makes attenuated input signal to echo suppressor 30 through making input signal and determined attenuation coefficient (standard value SUP_MIN or upper limit SUP_MAX), and output result's (step 46).
Through this configuration,, also can prevent the voice inflection even if echo suppressor 30 makes the voice decay of sending from the speaker of proximal lateral by error.
Simultaneously, if the speaker is in the environment that ambient noise is generally high level, then the sef-adapting filter 21 of Echo Canceller 20 does not upgrade filter coefficient in communication beginning back in the long time period.From said reason, Echo Canceller 20 is not restrained, and double talk detection device 23 can't correctly detect dual end communication.In the case, even if voice switch 10 is in accepting state and double talk detection device 23 does not detect dual end communication, echo suppressor 30 can not add damply output in statu quo with input signal yet, and this possibly cause the residual echo that makes us uncomfortable.
In this regard; Though Echo Canceller 20 is not fully convergence after the communication terminal via the other side begins communication, echo suppressor 30 is sending in the signal path and is inserting the particular decay amount when insertion waste distribution processor 15 estimates that voice switchs 10 are in accepting state.Also promptly, echo suppressor 30 makes the residual echo decay of making us uncomfortable, and Echo Canceller 20 is reached the pleasant environment that is used for speaker-phone communication thus in communication beginning back and insufficient convergence.
On the other hand, (as just having begun the back in communication) simultaneously from the proximal lateral and distal side input different phonetic if when total losses amount calculator 14 is just being operated in fixed mode, then voice switch 10 between accepting state and transmit status alternately.Therefore from said reason, echo suppressor 30 maloperations, and in the voice that sent inflection may take place, the level fluctuation of the voice that wherein sent.
In this regard; When double talk detection device 23 detected dual end communication when insertion waste distribution processor 15 estimates that voice switchs 10 are not in accepting state or in sending signal path, are just inserting the particular decay amount, echo suppressor 30 stopped the particular decay amount is inserted in the transmission signal path immediately.This makes and can prevent that the error fade because of sending signal from inflection taking place, and provides pleasant condition for speaker-phone communication thus.
The 4th embodiment
Fig. 9 shows the block diagram of the speaker-phone device of a fourth embodiment in accordance with the invention.In this embodiment, be characterised in that echo suppressor 30 adjusts attenuation through the signal level mean value that use to receive signal, and other basic configuration of present embodiment and the 3rd embodiment's is identical.Therefore, same components is represented by same numeral, and will be omitted the explanation to it.
In the present embodiment; Sef-adapting filter 21 is discerned the impulse response of acoustic echo path Hac adaptively; And come estimated echo component (acoustic echo) g (n) according to signal y (n) (that is, inputing to the reception signal of speaker amplifier G2) from distal side input.For estimated echo component g (n), upgrade filter coefficient hp (n) through using following formula:
Hp(n+1)＝hp(n)+K·F(Ey(n))
Here, p is tap (tap) number, and n is the sampling period, and K is the step-length gain, and F (n) is the coefficient update function.In addition, Ey (n) is the signal level mean value of input signal (reception signal) y (n), and it is through using the following formula in signal level mean value (SLA) arithmetic element 24 that provides in this sef-adapting filter 21 to calculate.Here, SPAN is the time period of the amplitude abs [y (n)] of increase this input signal y (n).
In addition, echo components (estimation) g (n) can calculate through using following formula:
In the present embodiment, echo suppressor 30 is by the SLA arithmetic element picked up signal level mean value Ey (n) that provides in the sef-adapting filter 21.
Hereinafter, will explain the operation of echo suppressor 30 with reference to flow chart shown in Figure 10.
On the other hand; When voice switch 10 is in accepting state and double talk detection device 23 and does not detect dual end communication, depend on the signal level mean value RS_AVE (n) (=Ey (n)) that calculates by SLA arithmetic element 24 by echo suppressor 30 attenuation coefficients that multiply each other with input signal that carry out.More specifically, when RS_AVE (n)＞TH, can confirm attenuation coefficient, and when RS_AVE (n)＜TH, can confirm attenuation coefficient according to following formula (2) according to following formula (1):
Here; SUP_MAX and SUP_MIN corresponding to loud (loud voice) (for example are respectively inhibition; OOdB acoustic pressure or bigger) signal level corresponding to typical problem (for example reaches; OO～OOdB acoustic pressure) the needed attenuation coefficient of signal level, and RS_AVEmax is loud signal level mean value RS_AVE (n).About formula (2); When each sampling period RS_AVE (n)≤TH; Attenuation coefficient multiply by special transition coefficient (transition coefficient) and is decreased to SUP_MIN gradually from SUP_MAX * RS_AVE (n)/RS_AVEmax, and wherein SUP_MIN is set at the lower limit of attenuation coefficient.
More specifically, echo suppressor 30 confirms at first whether attenuation coefficient is set at SUP_MIN (step 53).When attenuation coefficient was not set at SUP_MIN, echo suppressor 30 made it and changes multiplication, sets new attenuation coefficient (step 54) thus.Otherwise, then SUP_MIN being used as attenuation coefficient, this is because it is the lower limit of attenuation coefficient.
Next; As if RS_AVE (n)＞TH, also promptly satisfy the condition (step 55) of formula (1), then echo suppressor 30 is set at SUP_MAX * RS_AVE (n)/RS_AVEmax (step 56) with attenuation coefficient; Otherwise, use the attenuation coefficient of setting in the previous steps and do not change attenuation coefficient.At last, echo suppressor 30 multiplies each other through the attenuation coefficient that makes input signal and setting and makes attenuated input signal so that output (step 57).
Through present embodiment,, also can suppress the generation of voice inflection even if echo suppressor 30 all of a sudden makes the voice decay of sending from the speaker of proximal lateral.In addition; Owing to come signal calculated level mean value RS_AVE (n) through using the signal level mean value arithmetic element 24 that provides in the Echo Canceller 20; So the simplification that can reach configuration (for example; Lower standard in the minimizing of the procedure quantity of in DSP, carrying out, the DSP, be used for minimizing of stored program ROM capacity or the like), and cost reduces.
The 5th embodiment
Next, will explain the fifth embodiment of the present invention with reference to accompanying drawing.In the present embodiment, echo suppressor 30 combines signal level mean value (SLA) arithmetic element 24 that provides in the sef-adapting filter 21 of double talk detection device 23 and Echo Canceller 20 of voice switch 10, Echo Canceller 20 and in sending signal path, inserts attenuation.Other configuration of present embodiment is identical with the 4th embodiment.Therefore, same components is represented by same numeral, and will be omitted the explanation to it.
To come the operation of illustrated in detail echo suppressor 30 with reference to flow chart shown in Figure 11.Step 61 among Figure 11 to 67 with Figure 10 in step 51 to step 57 about the 4th embodiment identical.Therefore, with the explanation of omitting to it.
When voice switch 10 is not in accepting state, or when voice switch 10 is in accepting state when double talk detection device 23 detects dual end communication, echo suppressor 30 confirms further whether voice switchs 10 are in transmit status (step 68).When voice switch 10 was in transmit status, echo suppressor 30 was confirmed not have residual echo or do not have voice signal to be sent, and input signal is not added damply output (step 611) in statu quo.
If (hereinafter at speaker-phone device according to the present invention and the communicator that uses receiver; Be called " receiver communicator ") between executive communication; And the level of ambient noise is quite high the transmission signal that is sent to the receiver communicator from the speaker-phone device; When then the echo suppressor in the speaker-phone device 30 made the residual echo decay, ambient noise temporarily decayed.This decay of ambient noise postpones through one and is heard by receiver, and the speaker at receiver communicator place may be felt in the uncomfortable disconnection of making us in communication period is felt voice.
In this regard; In the present embodiment; When voice switch 10 is not in transmit status in the step 68 (for example; Insert waste distribution processor 15 and in sending signal attenuator 11 and receiving signal attenuation device 12, insert same loss amount (hereinafter, this state being called " intermediateness ")), echo suppressor 30 makes monotonously and sends the attenuation decay of inserting in the signal path.
More specifically, when voice switch 10 was not in transmit status in the step 68, echo suppressor 30 confirmed further whether attenuation coefficient is zero (step 69).If attenuation coefficient is zero, then handles being back to step 61, and do not change attenuation coefficient.Otherwise echo suppressor 30 is set new attenuation coefficient (step 610) through making attenuation coefficient and transformation multiplication.Also promptly, echo suppressor 30 makes attenuation coefficient (attenuation) reduce (shown in the line A among Figure 12, reducing monotonously) gradually through the processing of repeating step 61 or 62-＞step 68-＞step 69-＞step 610-＞step 61.
In the present embodiment, because echo suppressor 30 reduces the attenuation of inserting in the transmission signal path monotonously, so ambient noise can temporarily not decay.This makes the speaker be difficult to make receiver communicator place feel the disconnection sensation of making us uncomfortable.
Simultaneously; When the state changes of voice switch 10 is transmit status when attenuation coefficient (attenuation) reduces through the processing of repeating step 61 or 62-＞step 68-＞step 69-＞step 610-＞step 61 just monotonously; Echo suppressor 30 makes attenuation coefficient (attenuation) be reduced to zero (referring to, the dotted line B among Figure 12 for example) immediately.Therefore, in the voice that the speaker that can prevent at the other side's communicator place hears inflection takes place, this is all of a sudden to be decayed by echo suppressor 30 because of the voice (transmission voice) that the speaker from the speaker-phone device sends.
In addition; The state changes of voice switch 10 is that transmit status and double talk detection device 23 be not when detecting dual end communication when attenuation coefficient (attenuation) reduces through the processing of repeating step 61 or 62-＞step 68-＞step 69-＞step 610-＞step 61 just monotonously; Processing through execution in step 63 to 67 of echo suppressor 30 (referring to, the dotted line C among Figure 12 for example) and in sending signal path, insert a particular decay amount.This makes and can prevent that echo suppressor 30 from all of a sudden not inserting an attenuation and preventing the residual echo that makes us uncomfortable, and only makes the echo attenuation of making us uncomfortable in communication period exactly.
In the present embodiment, the time ratio (reducing ratio) that echo suppressor 30 reduces attenuation monotonously is constant (referring to, the line A among Figure 12 for example).When attenuation as stated during linear attenuation, be decreased to for zero required time period (fringe time section) to compare and to shorten with the situation that progressively makes the attenuation decay.
The 6th embodiment
Next, will explain according to a sixth embodiment of the invention with reference to figures 13 to Figure 15.Shown in figure 13, the difference of the 6th embodiment and the 5th embodiment is, between step 77 and 78, the step 712 of controlling attenuation based on ambient noise level is provided.Step 71 to 79 and step 710 and 711 with the 5th embodiment in the step 61 explained to 69 and step 610 and 611 identical, and will omit explanation to it.
In the present embodiment, echo suppressor 30 further combining environmental noise levels are controlled attenuation.The combining environmental noise level has been shown in flow chart shown in Figure 14 has controlled the processing of attenuation.
Also promptly, along with the ambient noise level of speaker-phone device one side uprises, the attenuation that echo suppressor 30 inserts in sending signal path reduces.Therefore, can suppress the instantaneous decay of ambient noise, make thus to be difficult to feel the sensation of breaking off.In the case, if echo suppressor reduces attenuation, then the attenuating of residual echo reduces.Yet when reality was used, residual echo was hidden by ambient noise, and in communication, can not cause trouble.
Hereinafter, with reference to the flow chart shown in Figure 14 and description taken in conjunction ambient noise level is controlled the processing of attenuation.
Echo suppressor detects (estimations) level (ambient noise level) LEVEL_NOISE of the ambient noise of continued presence in sending signal through using long-term average by the transmission signal of the input point Tin input of sending signal attenuator 11, and estimated ambient noise level LEVEL_NOISE and threshold value Nth are compared (step 821).When ambient noise level LEVEL_NOISE is threshold value Nth or more hour, echo suppressor 30 comes basis of calculation attenuation coefficient ATT (step 822) through using following formula:
ATT＝α×LEVEL_NOISE+β，α＜0
In addition, when ambient noise level LEVEL_NOISE exceeded threshold value Nth, how echo suppressor 30 ambient noise level LEVEL_NOISE were set at steady state value ATTmin (step 823) with standard attenuation coefficient ATT.
Subsequently, echo suppressor 30 will compare (step 824) with the standard attenuation coefficient ATT that calculates through step 821 to 823 processing through the attenuation coefficient (corresponding to the attenuation of the echo amount of estimating according to received signal level) that step 73 is calculated to 76 processing.When attenuation coefficient is standard attenuation coefficient ATT or more hour, echo suppressor 30 upgrades attenuation coefficient (step 825) with standard attenuation coefficient ATT, thereby advances to step 77.In addition, when attenuation coefficient overgauge attenuation coefficient ATT, echo suppressor 30 advances to step 77, and does not upgrade this attenuation coefficient.
Also be; In step 824 and 825; The attenuation of the echo amount that echo suppressor 30 will be estimated corresponding to foundation receives the speech signal level in the signal path (referring to; The curve D among Figure 15 for example) come with based on ambient noise level and definite attenuation (referring to, the curve E among Figure 15 for example) compares, and in sending signal path, insert the attenuation more by a small margin that has in the attenuation subsequently.In addition, when ambient noise level LEVEL_NOISE exceeded threshold value Nth, echo suppressor 30 was set at steady state value ATT based on ambient noise level LEVEL_NOISE with attenuation (attenuation coefficient).This way can prevent when ambient noise level is very high that remaining echo from not obtaining decay.
Though illustrated and described the present invention with respect to embodiment, it will be apparent to those skilled in the art that and to make various changes and modification under the situation of the category of the present invention that in not departing from following claim, defines.
Claims (19)
1. speaker-phone device comprises:
Microphone;
Loud speaker;
The voice switch; In order to loss is next switches between sending under the communications status and receiving through in receiving signal path and transmission signal path, providing; Wherein, Reception signal from the other side's communication terminal is sent to said loud speaker via said reception signal path, and the transmission signal of being collected by said microphone is sent to said the other side's said communication terminal via said transmission signal path;
Echo Canceller is used to suppress the acoustic echo that the acoustics coupling between said microphone and the said loud speaker causes;
The double talk detection device is used to detect dual end communication; And
Echo suppressor, in order to making the residual echo decay so that in said transmission signal path, insert the particular decay amount through combining said voice switch and/or said double talk detection device,
Wherein, said voice switch comprises: the transmitter side loss insertion unit that is used for inserting at said transmission signal path loss; Be used for inserting the receiver side loss insertion unit of loss at said reception signal path; And be used to control by said transmitter side loss and insert the insertion waste control unit that the respective amount of the loss of inserting the unit is inserted in unit and said receiver side loss,
Said insertion waste control unit comprises: total losses amount calculator; The lead-out terminal from said receiver side loss insertion unit in order to estimated path feeds back to the acoustic feedback gain that the input terminal of unit is inserted in said transmitter side loss via acoustic echo path, and calculates the summation of the said waste of in said path, inserting based on the said estimation that said acoustic feedback is gained; And insertion waste distribution processor; In order to monitor said transmission signal and said reception signal and to estimate communications status; And reach the value of calculating by said total losses amount calculator based on said results estimated; And definite distribution of inserting waste to said transmitter side loss insertion unit and said receiver side loss insertion unit, and
Said total losses amount calculator has renewal pattern and fixed mode; In said more new model; Based on to the corresponding estimation of said feedback oscillator and calculate and be updated in adaptively the summation of the said waste of inserting in the said path; In said fixed mode; The total losses amount is fixed in initial value, and said total losses amount calculator is operated under said fixed mode when said Echo Canceller is not fully restrained after the communication beginning, and said total losses amount calculator is operated under said more new model after said Echo Canceller is restrained fully.
2. speaker-phone device as claimed in claim 1; Wherein, If said insertion waste distribution processor estimates that said voice switch is in accepting state, then said echo suppressor inserts said particular decay amount in said transmission signal path, otherwise does not insert said particular decay amount.
3. speaker-phone device as claimed in claim 1, wherein, when said double talk detection device was just detecting dual end communication, said echo suppressor did not insert said particular decay amount in said transmission signal path, otherwise inserts said particular decay amount.
4. speaker-phone device as claimed in claim 3; Wherein, If said double talk detection device does not detect dual end communication and said insertion waste distribution processor estimates that said voice switch is in said accepting state, then said echo suppressor inserts said particular decay amount in said transmission signal path.
5. speaker-phone device as claimed in claim 4; Wherein, When said Echo Canceller is not fully restrained after the communication beginning; Only estimate that in said insertion waste distribution processor said voice switch is under the situation of said accepting state, said echo suppressor just inserts said particular decay amount in said transmission signal path.
6. like each described speaker-phone device among the claim 3-5; Wherein, In said transmission signal path, insert during the said particular decay amount; If said insertion waste distribution processor estimates that said voice switch is not in said accepting state or said double talk detection device detects dual end communication, then said echo suppressor stops said attenuation is inserted in the said transmission signal path immediately.
7. like each described speaker-phone device among the claim 1-6, wherein, said Echo Canceller comprises: sef-adapting filter is used for discerning adaptively the characteristic of echo path; Subtracter is used for deducting from said transmission signal the output of said sef-adapting filter; And said double talk detection device, be used to detect dual end communication, and when said double talk detection device detected dual end communication, said Echo Canceller did not upgrade the coefficient of said sef-adapting filter.
8. like each described speaker-phone device among the claim 1-7, wherein, said Echo Canceller, said voice switch and said echo suppressor are provided in order in said transmission signal path, and carry out its corresponding processing.
9. like each described speaker-phone device among the claim 1-8, wherein, said echo suppressor is adjusted said attenuation based on the said acoustic feedback gain of being estimated by said total losses amount calculator.
10. like each described speaker-phone device among the claim 1-6, wherein, said echo suppressor is based on the signal level mean value of said reception signal and adjust said attenuation.
11. speaker-phone device as claimed in claim 10; Wherein, When the said signal level of said reception signal is lower than threshold value; The said attenuation that said echo suppressor will insert in said transmission signal path is set at specified standard value, and when said signal level be said threshold value or when higher, said echo suppressor is in the said attenuation of adjustment in the upper limit to the scope of said specified standard value that is higher than said specified standard value.
12. speaker-phone device as claimed in claim 10, wherein, said Echo Canceller comprises: signal level mean value (SLA) arithmetic element is used to calculate the signal level mean value of said reception signal; Sef-adapting filter is used for discerning adaptively the characteristic of said echo path; And subtracter, be used for deducting the output of said sef-adapting filter, and said echo suppressor is adjusted said attenuation through using the said signal level mean value that is calculated by said signal level mean value arithmetic element from said transmission signal.
13. speaker-phone device as claimed in claim 1; Wherein, Only do not detect dual end communication and said insertion waste distribution processor estimates that said voice switch is under the situation of said accepting state at said double talk detection device; Said echo suppressor just inserts the particular decay amount in said transmission signal path; And when said insertion waste distribution processor estimates that said voice switch neither is in said accepting state and is not in said transmit status again; Or when said insertion waste distribution processor estimated that said voice switch is in said accepting state and said double talk detection device and detects dual end communication, said echo suppressor was reduced in the said attenuation of inserting in the said transmission signal path monotonously.
14. speaker-phone device as claimed in claim 13; Wherein, When the said communications status of when said attenuation reduces just monotonously, being estimated by said insertion waste distribution processor became said transmit status, said echo suppressor was reduced to zero with said attenuation immediately.
15. like claim 13 or 14 described speaker-phone devices; Wherein, When the said attenuation of in said transmission signal path, inserting reduces just monotonously; When said double talk detection device did not detect dual end communication and is said accepting state by the said communications status that said insertion waste distribution processor is estimated, said echo suppressor inserted said particular decay amount once more in said transmission signal path.
16. like each described speaker-phone device among the claim 13-15; Wherein, When the said communications status of being estimated by said insertion waste distribution processor neither is in said accepting state and is not in said transmit status again; Or when said communications status be said accepting state and said double talk detection device when detecting dual end communication, said echo suppressor reduces with the said attenuation that constant reduction ratio will insert in said transmission signal path.
17. speaker-phone device as claimed in claim 1; Wherein, Only when said double talk detection device does not detect dual end communication and is said accepting state by the said communications status that said insertion waste distribution processor is estimated; Said echo suppressor just inserts said particular decay amount in said transmission signal path; Said echo suppressor is estimated the ambient noise level that in said transmission signal, superposes, and based on the estimated result of said ambient noise level is reduced the said attenuation of inserting in the said transmission signal path when said ambient noise level uprises.
18. speaker-phone device as claimed in claim 17; Wherein, Said echo suppressor will according to the estimated echo of the said signal level of said reception signal amount with depend on that the attenuation of the ambient noise level that superposes in the said transmission signal compares, and in said transmission signal path, insert less one of numerical value in said echo amount and the said attenuation.
19. speaker-phone device as claimed in claim 18, wherein, when said noise level exceeded particular level, said echo suppressor was adjusted into steady state value based on said ambient noise level with said attenuation.
Applications Claiming Priority (9)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2009-103245 | 2009-04-21 | ||
| JP2009103245 | 2009-04-21 | ||
| JP2009-260173 | 2009-11-13 | ||
| JP2009260173A JP5712350B2 (en) | 2009-04-21 | 2009-11-13 | Loudspeaker |
| JP2010011384A JP5432741B2 (en) | 2010-01-21 | 2010-01-21 | Loudspeaker |
| JP2010-011384 | 2010-01-21 | ||
| JP2010-011383 | 2010-01-21 | ||
| JP2010011383A JP5297396B2 (en) | 2010-01-21 | 2010-01-21 | Loudspeaker |
| PCT/IB2010/000876 WO2010122398A1 (en) | 2009-04-21 | 2010-04-20 | Speakerphone apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102405634A true CN102405634A (en) | 2012-04-04 |
| CN102405634B CN102405634B (en) | 2014-08-06 |
Family
ID=44995589
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201080017260.XA Expired - Fee Related CN102405634B (en) | 2009-04-21 | 2010-04-20 | Speakerphone apparatus |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN102405634B (en) |
| TW (1) | TWI399968B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103475763A (en) * | 2013-09-26 | 2013-12-25 | 汉达尔通信技术(北京)有限公司 | Conversation echo canceling circuit of PSTN communication terminal |
| CN104754157A (en) * | 2013-12-26 | 2015-07-01 | 联芯科技有限公司 | Residual echo suppression method and system |
| CN108055417A (en) * | 2017-12-26 | 2018-05-18 | 杭州叙简科技股份有限公司 | One kind inhibits switching audio frequency processing system and method based on speech detection echo |
| CN111556210A (en) * | 2020-04-23 | 2020-08-18 | 深圳市未艾智能有限公司 | Call voice processing method and device, terminal equipment and storage medium |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI802108B (en) * | 2021-05-08 | 2023-05-11 | 英屬開曼群島商意騰科技股份有限公司 | Speech processing apparatus and method for acoustic echo reduction |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1416639A (en) * | 2000-01-27 | 2003-05-07 | 高通股份有限公司 | Improved system and method for implementation of echo canceller |
| US20040076288A1 (en) * | 2002-10-16 | 2004-04-22 | Cairns Douglas A. | Integrated noise cancellation and residual echo suppression |
| JP2006050342A (en) * | 2004-08-05 | 2006-02-16 | Matsushita Electric Works Ltd | Loudspeaker call device |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7065207B2 (en) * | 2003-09-11 | 2006-06-20 | Freescale Semiconductor, Inc. | Controlling attenuation during echo suppression |
| JP4456622B2 (en) * | 2007-07-25 | 2010-04-28 | 沖電気工業株式会社 | Double talk detector, double talk detection method and echo canceller |
-
2010
- 2010-04-20 TW TW99112310A patent/TWI399968B/en active
- 2010-04-20 CN CN201080017260.XA patent/CN102405634B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1416639A (en) * | 2000-01-27 | 2003-05-07 | 高通股份有限公司 | Improved system and method for implementation of echo canceller |
| US20040076288A1 (en) * | 2002-10-16 | 2004-04-22 | Cairns Douglas A. | Integrated noise cancellation and residual echo suppression |
| JP2006050342A (en) * | 2004-08-05 | 2006-02-16 | Matsushita Electric Works Ltd | Loudspeaker call device |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103475763A (en) * | 2013-09-26 | 2013-12-25 | 汉达尔通信技术(北京)有限公司 | Conversation echo canceling circuit of PSTN communication terminal |
| CN104754157A (en) * | 2013-12-26 | 2015-07-01 | 联芯科技有限公司 | Residual echo suppression method and system |
| CN104754157B (en) * | 2013-12-26 | 2017-06-16 | 联芯科技有限公司 | Method and system for suppressing residual echo |
| CN108055417A (en) * | 2017-12-26 | 2018-05-18 | 杭州叙简科技股份有限公司 | One kind inhibits switching audio frequency processing system and method based on speech detection echo |
| CN111556210A (en) * | 2020-04-23 | 2020-08-18 | 深圳市未艾智能有限公司 | Call voice processing method and device, terminal equipment and storage medium |
| CN111556210B (en) * | 2020-04-23 | 2021-10-22 | 深圳市未艾智能有限公司 | Call voice processing method and device, terminal equipment and storage medium |
Also Published As
| Publication number | Publication date |
|---|---|
| TW201039606A (en) | 2010-11-01 |
| CN102405634B (en) | 2014-08-06 |
| TWI399968B (en) | 2013-06-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110225214B (en) | Method, attenuation unit, system and medium for attenuating a signal | |
| KR100711869B1 (en) | Improved system and method for implementation of an echo canceller | |
| US6961422B2 (en) | Gain control method for acoustic echo cancellation and suppression | |
| CN106713570B (en) | Echo cancellation method and device | |
| CN105577961A (en) | Automatic tuning of a gain controller | |
| EP1786191A1 (en) | Acoustic echo canceller | |
| CN102405634B (en) | Speakerphone apparatus | |
| JP2002185371A (en) | Echo canceller with sound volume automatically regulating function | |
| US20060198511A1 (en) | Fast echo canceller reconvergence after TDM slips and echo level changes | |
| CN100591084C (en) | Device and method for suppressing echo, in particular in telephones | |
| JP5712350B2 (en) | Loudspeaker | |
| EP0917796A2 (en) | Dynamic optimization of handsfree microphone gain | |
| JP2005286796A (en) | Loudspeaker call device | |
| JP3941581B2 (en) | Loudspeaker | |
| JP5297396B2 (en) | Loudspeaker | |
| JP4900184B2 (en) | Loudspeaker | |
| JP5432741B2 (en) | Loudspeaker | |
| EP2430770B1 (en) | Noise suppression in a full-duplex audio communication terminal | |
| JP3404236B2 (en) | Loudspeaker | |
| WO2010122398A1 (en) | Speakerphone apparatus | |
| JP2007068223A (en) | Telephone set | |
| JP2007124162A (en) | Loudspeaker call device | |
| JP4349194B2 (en) | Loudspeaker | |
| AU2005242180B2 (en) | Improved system and method for implementation of an echo canceller | |
| JP2000270089A (en) | Amplified sound speech device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| ASS | Succession or assignment of patent right |
Owner name: MATSUSHITA ELECTRIC INDUSTRIAL CO, LTD. Free format text: FORMER OWNER: MATSUSHITA ELECTRIC WORKS LTD. Effective date: 20120227 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20120227 Address after: Osaka Japan Applicant after: Matsushita Electric Industrial Co., Ltd. Address before: Osaka Japan Applicant before: Matsushita Electric Works, Ltd. |
|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140806 Termination date: 20170420 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |