`Case 3:20-cv-03845-LB Document 1-16 Filed 06/11/20 Page 1 of 10
`
`EXHIBIT 16
`
`EXHIBIT 16
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`
`
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`
`
`
`
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`Case 3:20-cv-03845-LB Document 1-16 Filed 06/11/20 Page 2 of 10
`I 1111111111111111 11111 1111111111 111111111111111 IIIII 11111 lll111111111111111
`US007065206B2
`
`c12) United States Patent
`Pan
`
`(IO) Patent No.:
`(45) Date of Patent:
`
`US 7,065,206 B2
`Jun.20,2006
`
`(54) METHOD AND APPARATUS FOR ADAPTIVE
`ECHO AND NOISE CONTROL
`
`(75)
`
`Inventor: Jianhua Pan, Libertyville, IL (US)
`
`(73) Assignee: Motorola, Inc., Schaumburg, IL (US)
`
`( *) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 169 days.
`
`5,691,893 A
`5,768,124 A
`6,108,412 A *
`
`ll/ 1997 Stothers
`6/ 1998 Stothers et al.
`8/2000 Liu et al. ............... 379/406.09
`
`OTHER PUBLICATIONS
`
`Regine Le Bouquin Jeannes, Pascal Scalart, Gerard Faucon
`and Christophe Beaugeant, "Combined Noise and Echo
`Reduction in Hands-Free Systems: A Survey", IEEE Trans(cid:173)
`actions on Speech and Audio Processing, vol. 9, No. 8, Nov.
`2001, 13 pages.
`
`(21) Appl. No.: 10/718,157
`
`(22) Filed:
`
`Nov. 20, 2003
`
`(65)
`
`Prior Publication Data
`
`US 2005/0111655 Al May 26, 2005
`
`(51)
`
`Int. Cl.
`H04M 3/23
`(2006.01)
`H04B 15100
`(2006.01)
`(2006.01)
`H04M 9/08
`(52) U.S. Cl. ............................. 379/406.03; 379/392.01
`(58) Field of Classification Search ........... 379/392.01,
`379/406.09
`See application file for complete search history.
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`5,617,472 A * 4/1997 Yoshida et al. ........ 379/392.01
`5,680,393 A * 10/1997 Bourmeyster et al.
`379/406.01
`5,687,075 A
`11/1997 Stothers
`
`* cited by examiner
`
`Primary Examiner-Daniel Swerdlow
`(74) Attorney, Agent, or Firm-Matthew C. Loppnow
`
`(57)
`
`ABSTRACT
`
`A method and apparatus for adaptive echo and noise control.
`A signal can be received at an input to a communication or
`electronic device. Background noise in the signal can be
`determined. The order of noise suppression and echo can(cid:173)
`cellation can be adaptively determined based on the back(cid:173)
`ground noise in the signal. Adaptively determining the order
`of noise suppression and echo cancellation can be performed
`by comparing the background noise to at least one threshold,
`performing echo cancellation prior to noise suppression on
`the signal if the background noise is below the at least one
`threshold, and performing noise suppression prior to echo
`cancellation on the signal if the background noise is above
`the at least one threshold.
`
`20 Claims, 4 Drawing Sheets
`
`~110
`
`130
`
`140
`
`ECHO
`CANCELLER
`
`220
`
`210
`
`ADAPTIVE ECHO
`AND NOISE
`CONTROL SYSTEM
`CONTROLLER
`
`NOISE
`SUPPRESSOR
`
`230
`
`
`
`Case 3:20-cv-03845-LB Document 1-16 Filed 06/11/20 Page 3 of 10
`
`U.S. Patent
`
`Jun.20,2006
`
`Sheet 1 of 4
`
`US 7,065,206 B2
`
`120
`
`CONTROLLER
`
`~100
`
`130
`
`150
`
`160
`
`,,,-·
`
`/
`I
`ECHO (
`\ ' ~
`,,,,,,,,".
`SPEECH
`
`I
`I
`NOISE
`
`ADAPTIVE ECHO
`AND NOISE
`CONTROL
`
`--140
`
`VOCODER
`
`TX/RX
`
`110
`
`FIG. 1
`
`~110
`
`130
`
`140
`
`ECHO
`CANCELLER
`
`220
`
`210
`
`ADAPTIVE ECHO
`AND NOISE
`CONTROL SYSTEM
`CONTROLLER
`
`NOISE
`SUPPRESSOR
`
`230
`
`FIG. 2
`
`
`
`Case 3:20-cv-03845-LB Document 1-16 Filed 06/11/20 Page 4 of 10
`
`U.S. Patent
`
`Jun.20,2006
`
`Sheet 2 of 4
`
`US 7,065,206 B2
`
`-
`-
`
`340 '
`
`~220
`
`/ 350
`
`320, ,
`/
`
`.,,...,,,,
`
`310,
`
`,,
`
`.,-
`
`LMS & DBTK
`DETECTOR
`
`,,
`
`'
`
`-
`-
`
`', -
`X
`
`-
`+
`
`330
`
`FIG. 3
`
`~230
`
`-
`-
`
`420---
`
`CHANNEL NOISE
`ESTIMATE AND
`SUPPRESSION CONTROL
`
`410
`(
`
`-
`
`FREQUENCY
`DOMAIN
`CONVERSION
`
`440
`(
`
`-
`-
`
`TIME
`DOMAIN
`CONVERSION
`
`(~
`430
`MUL Tl-CHANNEL
`NOISE SUPPRESSION POINTER
`
`I' r-..
`
`FIG. 4
`
`
`
`Case 3:20-cv-03845-LB Document 1-16 Filed 06/11/20 Page 5 of 10
`
`U.S. Patent
`
`Jun.20,2006
`
`Sheet 3 of 4
`
`US 7,065,206 B2
`
`505
`
`START
`
`~500
`
`510
`
`INITIALIZE
`
`515
`
`OBTAIN
`TOTAL NOISE
`ENERGY TN
`
`530
`
`CHANGE TO
`HIGH NOISE
`SETTING
`
`CHANGE TO
`LOW NOISE
`SETTING
`
`545
`
`535
`
`SET FLAG
`
`SET FLAG
`
`550
`
`FIG. 5
`
`
`
`Case 3:20-cv-03845-LB Document 1-16 Filed 06/11/20 Page 6 of 10
`
`U.S. Patent
`
`Jun.20,2006
`
`Sheet 4 of 4
`
`US 7,065,206 B2
`
`~600
`
`220
`
`130
`
`230
`l
`140-17-\1 1
`NOiSE
`___
`-01---..i .. SUPPRESSION :
`II ____..
`.. ,
`
`ECHO
`CANCELLATION
`
`..
`
`I
`
`FIG. 6
`
`~700
`
`220
`
`ECHO
`CANCELLATION
`
`130
`
`140
`
`230
`
`NOISE
`SUPPRESSION
`
`FIG. 7
`
`
`
`Case 3:20-cv-03845-LB Document 1-16 Filed 06/11/20 Page 7 of 10
`
`US 7,065,206 B2
`
`1
`METHOD AND APPARATUS FOR ADAPTIVE
`ECHO AND NOISE CONTROL
`
`BACKGROUND
`
`2
`FIG. 5 is an exemplary flowchart illustrating the operation
`of the adaptive echo and noise control system according to
`one embodiment;
`FIG. 6 is an exemplary block diagram of a high noise
`5 setting of the adaptive echo and noise control system accord(cid:173)
`ing to one embodiment; and
`FIG. 7 is an exemplary block diagram of a low noise
`setting of the adaptive echo and noise control system accord(cid:173)
`ing to one embodiment.
`
`DETAILED DESCRIPTION
`
`1. Field
`The present disclosure is directed to a method and appa(cid:173)
`ratus for adaptive echo and noise control. More particularly,
`the present disclosure is directed to a method and apparatus
`for reconfiguring noise suppression and echo cancellation 10
`based on noise conditions.
`2. Description of Related Art
`Presently, communication devices are used in a variety of
`environments that have a variety of noise levels. For
`example, a mobile phone may be used in an office, at an 15
`amusement park, at a sporting event, at a party, in a car, or
`elsewhere. As another example, a traditional phone may be
`used in an office, at a construction site, in a home, or
`elsewhere. Unfortunately, these different environments with
`different noise levels cause a problem in that the different 20
`noise levels can make communication difficult. Thus, noise
`suppression may be used with communication devices to
`enhance communication. This creates an additional problem
`in determining the proper amount of noise suppression for
`optimal communication quality.
`Another problem exists because many communication
`devices may have loud speakers or may use speakerphones
`or car kits to provide handsfree operation. This causes the
`
`25
`
`The disclosure provides a method and apparatus for
`adaptive echo and noise control. According to one embodi(cid:173)
`ment, the present disclosure provides an electronic device.
`The electronic device can include an audio input configured
`to receive a received signal, an audio output configured to
`output an output signal, a transceiver configured to transmit
`a transmitted signal, and an adaptive echo and noise control
`system coupled to the audio input, the audio output, and the
`transceiver. The adaptive echo and noise control system can
`include an echo canceller and a noise suppressor. The
`adaptive echo and noise control system can be configured to
`adaptively determine the order of echo cancellation and
`noise suppression based on an amount of noise in the
`received signal to generate a desired signal. The adaptive
`echo and noise control system can also be configured to send
`the desired signal to the transceiver.
`The echo canceller can include a least mean square (LMS)
`adaptive filter and doubletalk detector and a subtraction or
`cancellation point. The noise suppressor can include a
`frequency domain converter, noise estimator and suppres(cid:173)
`sion control, a multi-channel noise suppression point, and a
`time domain converter. The adaptive echo and noise control
`system can further be configured to adaptively determine the
`order of noise suppression and echo cancellation by com(cid:173)
`paring the background noise to at least one threshold,
`performing echo cancellation prior to noise suppression on
`the signal if the background noise is below the at least one
`threshold, and performing noise suppression prior to echo
`cancellation on the signal if the background noise is above
`the at least one threshold.
`The adaptive echo and noise control system can addition(cid:173)
`ally be configured to adaptively determine the order of noise
`suppression and echo cancellation by performing echo can(cid:173)
`cellation prior to noise suppression on the signal if the
`background noise is below a first threshold of the at least one
`threshold and performing noise suppression prior to echo
`cancellation on the signal if the background noise is above
`a second threshold of the at least one threshold. The second
`threshold can be determined based on a noise threshold
`when the benefits of suppressing the environmental noise
`outweigh detriments of the nonlinear effect of noise sup-
`55 pression on echo cancellation. The first threshold can be
`determined based on a noise threshold when benefits of the
`nonlinear effect of noise suppression on echo cancellation
`outweigh detriments of noise suppressing the environmental
`noise. The second threshold can be greater than the first
`60 threshold, for example, to create a hysteresis zone to avoid
`switching oscillation. The adaptive echo and noise control
`system can also be configured to set an indicator to indicate
`a current order of echo cancellation and noise suppression.
`The amount of noise can be based on an estimated and
`65 smoothed noise level when there is no desired input nor
`acoustic echo received at the audio input of the electronic
`device.
`
`~~~~le~ ~:a~o::~c ~~:n:~!~!t~~n 0c:ut:e a c:~~!~:;i~~ 30
`
`35
`
`40
`
`45
`
`50
`
`device. This echo is caused by the microphone of a com(cid:173)
`munication device picking up the audio output by a speaker
`thus causing the communication device to resend audio
`originally sent by an originator back to the originator. This
`echo can be very disruptive to voice communication based
`on the echo magnitude and the time delay to when the echo
`is heard by the originator. To overcome the echo problem, an
`adaptive echo canceller can be used. Unfortunately, echo
`cancellation performance is severely affected by the near-
`end environmental noise and by the presence of near-end
`speech, such as doubletalk. The performance may be sub(cid:173)
`optimal when used in a noisy environment, and it even may
`be non-effective when used in a noisy environment together
`with doubletalk Furthermore, the use of noise suppression
`along with echo cancellation can cause additional problems.
`These problems are caused because the signal resulting from
`noise suppression can result in less efficient echo cancella(cid:173)
`tion. Furthermore, echo cancellation in a noisy environment
`may be inefficient when performed prior to noise suppres-
`S!On.
`Thus, there is a need for a method and
`adaptive echo and noise control.
`
`apparatus for
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`The embodiments of the present invention will be
`described with reference to the following figures, wherein
`like numerals designate like elements, and wherein:
`FIG. 1 is an exemplary block diagram of a communication
`device according to one embodiment;
`FIG. 2 is an exemplary block diagram of an adaptive echo
`and noise control system according to a related embodiment;
`FIG. 3 is an exemplary block diagram of an echo canceller
`according to a related embodiment;
`FIG. 4 is an exemplary block diagram of a noise suppres(cid:173)
`sor according to a related embodiment;
`
`
`
`Case 3:20-cv-03845-LB Document 1-16 Filed 06/11/20 Page 8 of 10
`
`US 7,065,206 B2
`
`5
`
`3
`FIG. 1 is an exemplary block diagram of a communication
`device 100 according to another embodiment. The commu(cid:173)
`nication device 100 may be a mobile communication device
`such as a cellular phone, or may also be a telephone, a
`personal computer, a personal digital assistant, or any other
`device that is capable of sending and receiving communi(cid:173)
`cation signals. The communication device 100 can include
`an audio output 130, an audio input 140, an adaptive echo
`and noise control system 110, and a controller 120. The
`communication device 100 may also include a vocoder 150 10
`and a transceiver 160. The transceiver 160 may include a
`transmitter and/or a receiver. The audio input 140 can
`include a microphone, an attached speakerphone, a headset,
`a car kit, or any other audio input device. The audio output
`130 can include, a speaker, a transducer, an attached speak- 15
`erphone, a headset, a car kit, or any other audio output
`device. All or some of the components may reside within the
`controller 120. Also, all or some of the components may be
`implemented as hardware or software.
`In operation, the audio output 130 can generate an output 20
`acoustic signal. The audio input 140 can receive an input
`acoustic signal such as speech. The input acoustic signal
`may include a desired signal component, a noise signal
`component, and an echo signal component. The controller
`120 can control the operations of the communication device 25
`100. For example, the controller 120 can send a command
`signal to the adaptive echo and noise control system 110 to
`enable, disable, and control the operation of the adaptive
`echo and noise control system 110. The vocoder 150 can be
`used to compress and decompress an audio stream to reduce 30
`the bandwidth and/or the data rate of a transmitted signal.
`The vocoder 150 is not necessary for operation of the
`communication device 100 depending on the type of com(cid:173)
`munication device being used. The transceiver 160 can
`transmit and receive signals across a network such as a 35
`wireless network, a landline network, a wide area network,
`or any other communication network. For example, the
`transceiver 160 can be applicable to wireless or wired
`telephones. The transceiver 160 can be used for voice over
`IP, for a cordless phone, for a wireless phone, for a phone 40
`with an attached speakerphone, or for any other communi(cid:173)
`cation device.
`According to one embodiment, the adaptive echo and
`noise control system 110 can adaptively remove or reduce
`echo and noise in a signal. For example, the adaptive echo 45
`and noise control system 110 can adaptively remove or
`reduce echo and noise in the acoustic signal received by the
`audio input 140. The adaptive echo and noise control system
`110 can operate on frame based signals, sampled signals, or
`any other signal type.
`According to a related embodiment, the adaptive echo and
`noise control system 110 can receive a signal at an input 140
`to the communication device 100, determine background
`noise in the signal, and adaptively determine the order of
`noise suppression and echo cancellation based on the back- 55
`ground noise in the signal. The adaptive echo and noise
`control system 110 can adaptively determine the order of
`noise suppression and echo cancellation by comparing the
`background noise to at least one threshold, performing echo
`cancellation prior to noise suppression on the signal if the 60
`background noise is below the at least one threshold, and
`performing noise suppression prior to echo cancellation on
`the signal if the background noise is above the at least one
`threshold. The background noise can be based on an esti(cid:173)
`mated and smoothed noise level when there is no desired 65
`input nor echo received at the input 140 of the communi(cid:173)
`cation device 100. The adaptive echo and noise control
`
`4
`system 110 can also adaptively determine the order of noise
`suppression and echo cancellation by performing echo can(cid:173)
`cellation prior to noise suppression on the signal if the
`background noise is below a first threshold of the at least one
`threshold and performing noise suppression prior to echo
`cancellation on the signal if the background noise is above
`a second threshold of the at least one threshold. The second
`threshold can be determined based on a noise threshold
`when the benefits of suppressing the environmental noise
`outweigh the detriments of the nonlinear effect of noise
`suppression on echo cancellation. The first threshold can be
`determined based on a noise threshold when the detriments
`of the nonlinear effect of noise suppression on echo cancel(cid:173)
`lation outweigh the benefits of suppressing the environmen(cid:173)
`tal noise. The second threshold can be greater than the first
`threshold, for example, to create a hysteresis zone to avoid
`switching oscillation. The adaptive echo and noise control
`system 110 can also set an indicator to indicate a current
`order of echo cancellation and noise suppression.
`According to another embodiment, the adaptive echo and
`noise control system 110 can receive an acoustic signal at an
`input 140 to the mobile communication device, the acoustic
`signal can include a speech component, an echo component,
`and a noise component, obtain the noise component in the
`acoustic signal, compare the noise component to at least one
`threshold, configure the order of echo cancellation and noise
`suppression to perform echo cancellation prior to noise
`suppression on the acoustic signal if the noise component is
`below the at least one threshold to obtain a desired signal,
`configure the order of echo cancellation and noise suppres(cid:173)
`sion to perform noise suppression prior to echo cancellation
`on the acoustic signal if the noise component is above the at
`least one threshold to obtain a desired signal, and transmit
`the desired signal. The adaptive echo and noise control
`system 110 can also set an indicator to indicate a current
`order of echo cancellation and noise suppression.
`FIG. 2 is an exemplary block diagram of the adaptive
`echo and noise control system 110 according to a related
`embodiment. The adaptive echo and noise control system
`110 can include an adaptive echo and noise control system
`controller 210, an echo canceller 220, and a noise suppressor
`230. In operation, the adaptive echo and noise control
`system controller 210 can control the operations of the
`adaptive echo and noise control system 110. For example,
`the adaptive echo and noise control system controller 210
`can control the routing of signals to the echo canceller 220
`and the noise suppressor 230 to adaptively modify the order
`of echo cancellation and noise suppression. The echo can(cid:173)
`celler 220 can adaptively remove and/or reduce acoustic
`50 echo in the signal received by the audio input 140. The noise
`suppressor 230 can adaptively remove and/or reduce back(cid:173)
`ground noise in the signal received by the audio input 140.
`The adaptive echo and noise control system controller 210
`can then take the resulting echo cancelled and noise sup(cid:173)
`pressed desired signal and send it to the transceiver 160 for
`transmission.
`FIG. 3 is an exemplary block diagram of an echo canceller
`220 according to a related embodiment. The echo canceller
`220 can include a least mean square (LMS) adaptation
`control and doubletalk detector 310, an adaptive filter 320,
`and a cancellation point 330. In operation, the LMS adap-
`tation control and doubletalk detector 310 can control the
`adaptive filter 320 based on an input signal 340, an echo
`residue signal and based on a signal received from the
`transceiver 160 at the input 350. This echo residue signal can
`be based on signal energy from the input 340 and signal
`energy from the echo cancelled signal after the cancellation
`
`
`
`Case 3:20-cv-03845-LB Document 1-16 Filed 06/11/20 Page 9 of 10
`
`US 7,065,206 B2
`
`5
`point 330. The cancellation point 330 can subtract the output
`of the adaptive filter 320 from the signal at the input 340 to
`obtain the echo cancelled signal.
`FIG. 4 is an exemplary block diagram of a noise suppres(cid:173)
`sor 230 according to a related embodiment. The noise
`suppressor 230 can include a frequency domain converter
`410, channel noise estimate and adaptive suppression con(cid:173)
`trol block 420, multi-channel noise suppression point 430,
`and a time domain converter 440. In operation the noise
`suppressor 230 can receive a signal including a desired
`signal portion and an undesired signal portion. For example,
`the signal can include speech and noise. The frequency
`domain converter 410 can convert the input signal from time
`domain to frequency domain, for example, using a fast
`Fourier transformation (FFT). The channel noise estimate
`and suppression control block 420 can include voice activity
`detection (VAD). It generates a noise estimate based on the
`input signal and controls the multi-channel noise suppres(cid:173)
`sion point 430 to adaptively and selectively suppress the
`environmental noise in the different frequency channels. The
`time domain converter 440 can convert the noise suppressed
`signal from frequency domain to time domain for generating
`the output signal. It is to be understood that the noise
`estimate and suppression can also be carried out in the time
`domain to remove or reduce the undesired signal portion.
`FIG. 5 is an exemplary flowchart 500 illustrating the
`operation of the adaptive echo and noise control system 110
`according to another embodiment. In step 505, the flowchart
`begins. In step 510, the adaptive echo and noise control
`system 110 intializes the echo canceller 220, the noise
`suppressor 230, and the initial order of echo canceller and
`noise suppression processing. For example, the adaptive
`echo and noise control system 110 can set an indicator, such
`as a flag, to indicate a current order of noise suppression and
`echo cancellation. According to one embodiment, the order
`is originally set for a low noise order where echo cancella(cid:173)
`tion is performed before noise suppression. This order can
`be useful in a low noise environment because noise sup(cid:173)
`pression can be a non-linear process that can cause a
`detrimental effect on echo cancellation. However, in a high
`noise environment, the benefits of noise suppression out(cid:173)
`weigh the detrimental effect. Thus, the order can be reversed
`for a high noise environment. In step 515, the adaptive echo
`and noise control system 110 can obtain a current total noise
`level determined by the noise suppressor 230, for example,
`by a summation of the noise signal energy of all or some
`frequency channels Also, smoothing of the total noise
`energy TN can be performed based on low-pass filtering the
`noise level for smoother operation. In step 520, the adaptive
`echo and noise control system 110 can determine a current
`order of noise suppression and echo cancellation. For
`example, the order can be determined based on the indicator
`set in step 510. If the adaptive echo and noise control system
`110 determines the order is a low noise order, in step 525,
`the adaptive echo and noise control system 110 determines 55
`if the total noise energy is greater than or equal to a high
`noise threshold THIGH- If not, the adaptive echo and noise
`control system 110 maintains the current low noise status
`and continues the process in step 515. If so, in step 530, the
`adaptive echo and noise control system 110 switches to a 60
`high noise setting. For example, the adaptive echo and noise
`control system 110 can switch to a high noise setting by first
`noise suppressing an incoming signal, then echo canceling
`the noise suppressed signal as illustrated in FIG. 6. In step
`535, the adaptive echo and noise control system 110 can set 65
`an indicator or flag to indicate the high noise setting and
`returns to step 515.
`
`6
`If, in step 520, the adaptive echo and noise control system
`110 determines the current order is a high noise order, in step
`540, the adaptive echo and noise control system 110 deter(cid:173)
`mines if the total noise energy is less than or equal to a low
`5 noise threshold T Low- The low noise threshold may be equal
`to or less than the high noise threshold. For example, the low
`noise threshold and the high noise threshold may be equal
`for ease of determination. Alternately, low noise threshold
`and the high noise threshold may be different for better
`10 system stability. Both the low noise threshold and the high
`noise threshold may be determined based on experimenta(cid:173)
`tion to determine their optimal values. If the total noise
`energy is not less than or equal to the low noise threshold,
`the adaptive echo and noise control system 110 maintains
`15 the current high noise status and continues the process in
`step 515. If, in step 540, the total noise energy is less than
`or equal to the low noise threshold, in step 545, the adaptive
`echo and noise control system 110 switches to a low noise
`setting. For example, the adaptive echo and noise control
`20 system 110 can switch to a low noise setting by first echo
`canceling an incoming signal, then noise suppressing the
`echo cancelled signal as illustrated in FIG. 7. In step 550, the
`adaptive echo and noise control system 110 can set an
`indicator or flag to indicate the low noise setting and can
`25 return to step 515.
`The method of this invention is preferably implemented
`on a programmable processor. However, the controller 120,
`the adaptive echo and noise control system 110, and/or any
`other components of the communication device 100 the may
`30 also be implemented on a general purpose or special purpose
`computer, a programmed microprocessor or microcontroller
`and peripheral integrated circuit elements, an ASIC or other
`integrated circuit, a hardware electronic or logic circuit such
`as a discrete element circuit, a progranimable logic device
`35 such as a PLD, PLA, FPGA or PAL, or the like. In general,
`any device on which resides a finite state machine capable
`of implementing the flowcharts shown in the Figures may be
`used to implement the processor functions of this invention.
`While this invention has been described with specific
`40 embodiments thereof, it is evident that many alternatives,
`modifications, and variations will be apparent to those
`skilled in the art. For example, various components of the
`embodiments may be interchanged, added, or substituted in
`the other embodiments. Also, all of the elements of each
`45 figure are not necessary for operation of the disclosed
`embodiments. For example, one of ordinary skill in the art
`of the disclosed embodiments would be enabled to make and
`use the invention by simply employing the elements of the
`independent claims. Accordingly, the preferred embodi-
`50 ments of the invention as set forth herein are intended to be
`illustrative, not limiting. Various changes may be made
`without departing from the spirit and scope of the invention.
`
`What is claimed is:
`1. A method for echo and noise control in a communica(cid:173)
`tion device, comprising:
`receiving a signal at an input to the communication
`device;
`determining background noise in the signal; and
`adaptively determining an order of noise suppression and
`echo cancellation based on the background noise in the
`signal.
`2. The method according to claim 1, wherein the step of
`adaptively determining the order of noise suppression and
`echo cancellation further comprises:
`comparing the background noise to at least one threshold;
`
`
`
`Case 3:20-cv-03845-LB Document 1-16 Filed 06/11/20 Page 10 of 10
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`US 7,065,206 B2
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`10
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`8
`12. The electronic device according to claim 9, wherein
`the adaptive echo and noise control system is further con(cid:173)
`figured to adaptively determine the order of noise suppres(cid:173)
`sion and echo cancellation by
`comparing the background noise to at least one threshold,
`performing echo cancellation prior to noise suppression
`on the signal if the background noise is below the at
`least one threshold, and
`performing noise suppression prior to echo cancellation
`on the signal if the background noise is above the at
`least one threshold.
`13. The electronic device according to claim 12, wherein
`the adaptive echo and noise control system is further con(cid:173)
`figured to adaptively determine the order of noise suppres(cid:173)
`sion and echo cancellation by
`performing echo cancellation prior to noise suppression
`on the signal if the background noise is below a first
`threshold of the at least one threshold, and
`performing noise suppression prior to echo cancellation
`on the signal if the background noise is above a second
`threshold of the at least one threshold.
`14. The electronic device according to claim 13, wherein
`the second threshold is determined based on a noise thresh(cid:173)
`old when benefits of suppressing the environmental noise
`outweigh detriments of the nonlinear effect of noise sup(cid:173)
`pression on echo cancellation.
`15. The electronic device according to claim 13, wherein
`the first threshold is determined based on a noise threshold
`when detriments of the nonlinear effect of noise suppression
`on echo cancellation outweigh benefits of noise suppressing
`the environmental noise.
`16. The electronic device according to claim 13, wherein
`the second threshold is greater than the first threshold.
`17. The electronic device according to claim 9, wherein
`35 the adaptive echo and noise control system is further con(cid:173)
`figured to set an indicator to indicate a current order of echo
`cancellation and noise suppression.
`18. The electronic device according to claim 9, wherein
`the amount of noise is based on an estimated noise level
`40 when there is no desired input received at the audio input of
`the electronic device.
`19. A method for echo cancellation and noise suppression
`in a mobile communication device, comprising:
`receiving an acoustic signal at an input to the mobile
`communication device, the acoustic signal including a
`speech component, an echo component, and a noise
`component;
`obtaining the noise component in the acoustic signal;
`comparing the noise component to at least one threshold;
`configuring the order of echo cancellation and noise
`suppression to perform echo cancellation prior to noise
`suppression on the acoustic signal if the noise compo(cid:173)
`nent is below the at least one threshold to obtain a
`desired signal;
`configuring the order of echo cancellation and noise
`suppression to perform noise suppression prior to echo
`cancellation on the acoustic signal if the noise compo(cid:173)
`nent is above the at least one threshold to obtain a
`desired signal; and
`transmitting the desired signal.
`20. The method according to claim 19, further comprising
`setting an indicator to indicate a current order of echo
`cancellation and noise suppression.
`
`7
`performing echo cancellation prior to noise suppression
`on the signal if the background noise is below the at
`least one threshold; and
`performing noise suppression prior to echo cancellation
`on the signal if the background noise is above the at 5
`least one threshold.
`3. The method according to claim 2, wherein the back(cid:173)
`ground noise is based on an estimated noise level when there
`is no desired input received at the input of the communica-
`tion device.
`4. The method according to claim 2, wherein the step of
`adaptively determining the order of noise suppression and
`echo cancellation further comprises:
`performing echo cancellation prior to noise suppression
`on the signal if the background noise is below a first 15
`threshold of the at least one threshold; and
`performing noise suppression prior to echo cancellation
`on the signal if the background noise is above a second
`threshold of the at least one threshold.
`5. The method according to claim 4, wherein the second 20
`threshold is determined based on a noise threshold when
`benefits of suppressing the environmental noise outweigh
`detriments of the nonlinear effect of noise suppression on
`echo cancellation.
`6. The method according to claim 4, wherein the first 25
`threshold is determined based on a noise threshold when
`detriments of the nonlinear effect of noise suppression on
`echo cancellation outweigh benefits of noise suppressing the
`environmental noise.
`7. The method according to claim 4, wherein the second 30
`threshold is greater than the first threshold.
`8. The method according to claim 1, further comprising
`setting an indicator to indicate a current order of echo
`cancellation and noise suppression.
`9. An electronic device, comprising:
`an audio input configured to receive a received signal;
`an audio output configured to output an output signal;
`a transceiver configured to transmit a transmitted signal;
`and
`an adaptive echo and noise control system coupled to the
`audio input, the audio output, and the transceiver, the
`adaptive echo and noise control system including
`an echo canceller; and
`a noise suppressor,
`wherein the adaptive echo and noise control s