WO2023022435A1 - Noise reduction apparatus, noise reduction method, and multimedia device - Google Patents

Noise reduction apparatus, noise reduction method, and multimedia device Download PDF

Info

Publication number
WO2023022435A1
WO2023022435A1 PCT/KR2022/011992 KR2022011992W WO2023022435A1 WO 2023022435 A1 WO2023022435 A1 WO 2023022435A1 KR 2022011992 W KR2022011992 W KR 2022011992W WO 2023022435 A1 WO2023022435 A1 WO 2023022435A1
Authority
WO
WIPO (PCT)
Prior art keywords
noise
signal
unit
frequency
noise reduction
Prior art date
Application number
PCT/KR2022/011992
Other languages
French (fr)
Inventor
Hui GU
Original Assignee
Samsung Electronics Co., Ltd.
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Samsung Electronics Co., Ltd. filed Critical Samsung Electronics Co., Ltd.
Publication of WO2023022435A1 publication Critical patent/WO2023022435A1/en

Links

Images

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17853—Methods, e.g. algorithms; Devices of the filter
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1781—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase characterised by the analysis of input or output signals, e.g. frequency range, modes, transfer functions
    • G10K11/17821—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase characterised by the analysis of input or output signals, e.g. frequency range, modes, transfer functions characterised by the analysis of the input signals only
    • G10K11/17823—Reference signals, e.g. ambient acoustic environment
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1787—General system configurations
    • G10K11/17873—General system configurations using a reference signal without an error signal, e.g. pure feedforward
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/108—Communication systems, e.g. where useful sound is kept and noise is cancelled
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/321—Physical
    • G10K2210/3218—Filters other than the algorithm-related filters

Definitions

  • the present invention relates to a noise reduction apparatus and a noise reduction method.
  • Noise is one of the major pollution sources among the above that is harmful to people's physical and mental health.
  • Sound noise or even serious noise usually exists. It is harmful for long-term and close contact workers to their physical and mental health including hearing loss, fatigue, and attention loss. Therefore, there is a strong demand for noise reduction in situations that noise is more and more serious while people are increasingly pursuing physical and mental health for life quality.
  • noise control should be carried out through the source, the transmission path, or the receiver.
  • noise reduction methods mainly comprise passive noise reduction method and active noise reduction method.
  • Passive noise reduction involves approaches of shock absorption, sound absorption, and sound insulation, which separates the external noise from the ear based on physical properties and usually insulates noise with sound-insulating materials. It is very effective for high-frequency noise and is typically reduced by about 15-20dB.
  • the passive noise reduction method is simple in principle and low in cost but poor in effect. Generally, high-density acoustical insulation or headphone is used need which may result in uncomfortable.
  • Passive noise reduction has a good effect on isolating high-frequency noise like acoustic panels near roads, but less effect on low-frequency noise in small spaces like air conditioner noise, projector noise, engine noise, sound of rain, sound of wind, sound of wave, sound of cicadas , etc.
  • the active noise reduction is based on the principle of two sound wave acoustic destructive interference or acoustic radiation suppression, comprising an artificially manufactured controlled sound source (secondary sound source) generating signals that are equal in value and opposite in phase with the original noise source (primary sound source) so that counterbalances mutually, thereby the purpose of noise reduction is achieved.
  • the object of the present invention is to provide a noise reduction apparatus and a noise reduction method for reducing undesired noise in the object area by signal processing, audio processing, and noise control.
  • the present invention provides a noise reduction apparatus comprising a microphone unit for real-time monitoring the environmental noise and generating an anti-noise signal-N1; a filtering unit for compensating the frequency characteristics of the anti-noise signal-N1 to-N2; a carrier loading unit for loading the compensated signal-N2 onto a high-frequency carrier C so as to form an envelope signal-N3 provided with opposite phase to the noise signal N1; an amplifier unit for amplifying the value of the envelope signal -N3 to -N4 provided with the same value of the noise signal N1; and a speaker unit for playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise.
  • the microphone unit comprises a reverse microphone component.
  • a carrier generation unit for generating the high-frequency carrier C.
  • the frequency of the high-frequency carrier C is higher than the upper limit of the human hearing frequency.
  • the amplifier unit Preferably, comprising a comparator unit for comparing the value of the envelope signal-N3 and the noise signal N1, thereby the amplifier unit adjusting the value of the envelope signal-N3.
  • the filtering unit removes the high-frequency part beyond the upper limit of the human hearing frequency from the anti-noise signal-N1.
  • the filtering unit further comprising power supply components of a resistor R1 and a voltage source VDC which are connected with the microphone unit; impedance matching components of a capacitor C1 for removing the direct current part from the anti-noise signal input by the microphone unit; low-pass filtering components of R2, R3, C2, and C3 composing a second-order low-pass filter for removing the high-frequency part from the output signal of the impedance matching components and preserving the low-frequency part of the anti-noise signal.
  • the present invention provides a noise reduction method comprising the steps of S1: real-time monitoring the environmental noise and generating an anti-noise signal-N1; S2: removing the high-frequency part beyond the upper limit of the human hearing frequency from the anti-noise signal-N1 and matching the impedance with the output to compensate the frequency characteristics to-N2; S3: loading the compensated signal-N2 onto a high-frequency carrier C provided with higher frequency than the upper limit of the human hearing so as to form an envelope signal-N3 provided with opposite phase to the noise signal N1; S4: amplifying the value of the envelope signal -N3 to -N4 provided with the same value of the noise signal N1; S5: playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise.
  • the present invention provides a multimedia device, comprising the noise reduction apparatus according to the above.
  • the mobile phone comprising any of the mobile phone, the tablet computer, the notebook computer, the desktop computer, and the all-in-one computer.
  • a relatively quiet environment can be created by using devices such as laptops, mobile phones, all-in-one computers, or tablets;
  • a three-dimensional low noise region at a certain position can be created with the anti-noise signal output by the speaker.
  • Figure 1 is a block diagram of the noise reduction apparatus according to the present invention.
  • Figure 2 is a schematic diagram of the noise reduction apparatus according to the present invention.
  • Figure 3 is a circuit diagram of the filtering unit of the noise reduction apparatus according to the present invention.
  • Figure 4 is a flow chart of the noise reduction method according to the present invention.
  • Figure 5 is an oscillogram showing the phase of the input signal and output signal of different types of the microphone unit.
  • Figure 6 is an oscillogram showing the signal before and after the carrier loading unit.
  • the present embodiment discloses a noise reduction apparatus, which can be applied to such multimedia devices as mobile phones, tablets, notebooks, desktop computers, and all-in-one computers.
  • the existing noise reduction method is mainly based on the active noise reduction technology eliminating the remote signal noise during a voice call.
  • the environmental noise cannot be reduced due to the fact that only the voice noise during the call can be reduced.
  • the purpose of the scheme is to reduce the undesired environmental noise in the object area by signal processing, audio processing, and noise control, thereby reducing the harm of the environmental noise to the physiology and mental health of people.
  • FIG. 1 is a block diagram of the noise reduction apparatus according to the present invention.
  • Figure 2 is a schematic diagram of the noise reduction apparatus according to the present invention.
  • the present embodiment discloses a noise reduction apparatus comprising a microphone unit for real-time monitoring the environmental noise and generating an anti-noise signal-N1; a filtering unit for compensating the frequency characteristics of the anti-noise signal-N1 to-N2; a carrier loading unit for loading the compensated signal-N2 onto a high-frequency carrier C so as to form an envelope signal-N3 provided with opposite phase to the noise signal N1; an amplifier unit for amplifying the value of the envelope signal -N3 to -N4 provided with the same value of the noise signal N1; and a speaker unit for playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise.
  • Communication channel1 can be wireless, while communication channel2 can be wire or PCB wire.
  • a comparator unit can be arranged before the amplifier unit which compares the value of the envelope signal-N3 and the noise signal N1, thereby the amplifier unit adjusts the value of the envelope signal-N3.
  • the filtering unit removes the high-frequency part beyond the upper limit of the human hearing frequency from the anti-noise signal-N1. The reason for this is that the high-frequency part of the environmental noise higher than the upper limit of the human hearing frequency does not affect human hearing, so it is not necessary to perform noise reduction treatment on this part but make the noise reduction easier.
  • the high-frequency carrier C is generated by a carrier generation unit.
  • the frequency of the high-frequency carrier C is higher than the upper limit of the human hearing frequency, because that no audible noise can be produced during the noise reduction process.
  • FIG. 3 is a circuit diagram of the filtering unit of the noise reduction apparatus according to the present invention.
  • the filtering unit further comprising the power supply components, the impedance matching components, and the low-pass filtering components.
  • the power supply components are consist of a resistor R1 and a voltage source VDC which are connected with the microphone unit.
  • the impedance matching components are consist of a capacitor C1 for removing the direct current part from the anti-noise signal input by the microphone unit.
  • the low-pass filtering components are consist of R2, R3, C2, and C3 composing a second-order low-pass filter for removing the high-frequency part from the output signal of the impedance matching components and preserving the low-frequency part of the anti-noise signal.
  • Figure 4 is a flow chart of the noise reduction method according to the present invention.
  • the present embodiment discloses a noise reduction method comprising the steps of,
  • S1 a reverse microphone component real-time monitoring the environmental noise and generating an anti-noise signal-N1;
  • S4 amplifying the value of the envelope signal -N3 to -N4 provided with same value of the noise signal N1;
  • S5 playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise.
  • the advantages of the present noise reduction method are that,
  • a relatively quiet environment can be created by using devices such as laptops, mobile phones, all-in-one computers, or tablets;
  • a three-dimensional low noise region at a certain position can be created with the anti-noise signal output by the speaker.
  • Figure 5 is an oscillogram showing the phase of the input signal and output signal of different types of the microphone unit.
  • the output signal of a microphone is provided with the same phase of the input signal, while the output signal of a reverse microphone is provided with the opposite phase of the input signal.
  • the present embodiment takes the reverse microphone that has the opposite phase of the input signal. In this case, the output signal is opposite in phase with the input signal (i.e., 180 degrees).
  • the microphone unit receives the external noise and outputs a microphone signal (MIC +, MIC-) with reverted output characteristics of the received external noise.
  • the microphone receives an input signal (e.g., external noise) and outputs an output signal (e.g., reverse noise) that is opposite in phase with the input signal, and the speaker unit outputs the reverse audio signal (Audio +, Audio-).
  • an input signal e.g., external noise
  • an output signal e.g., reverse noise
  • the speaker unit outputs the reverse audio signal (Audio +, Audio-).
  • Figure 6 is an oscillogram showing the signal before and after the carrier loading unit.
  • the environmental noise is acquired by the microphone component to generate an anti-noise signal-N1 which is compensated to form a signal -N2 by the filtering unit.
  • the compensated signal-N2 is loaded onto a high-frequency carrier C to form an envelope signal-N3 provided with the opposite phase to the noise signal N1.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)

Abstract

Disclosed are a Noise Reduction Apparatus, Noise Reduction Method, And Multimedia Device. a noise reduction apparatus comprising a microphone unit for real-time monitoring the environmental noise and generating an anti-noise signal-N1; a filtering unit for compensating the frequency characteristics of the anti-noise signal-N1 to-N2; a carrier loading unit for loading the compensated signal-N2 onto a high-frequency carrier C so as to form an envelope signal-N3 provided with opposite phase to the noise signal N1; an amplifier unit for amplifying the value of the envelope signal -N3 to -N4 provided with the same value of the noise signal N1; and a speaker unit for playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise. With the above-mentioned technical proposals, the advantages of the present invention is that a relatively quiet environment can be created in a noisy environment by using devices such as laptops, mobile phones, all-in-one computers or tablets, and undesired sound waves are destructively interfered to greatly reduce undesired noise under the active noise reduction control, and a three-dimensional low noise region at a certain position can be created with the anti-noise signal output by the speaker.

Description

NOISE REDUCTION APPARATUS, NOISE REDUCTION METHOD, AND MULTIMEDIA DEVICE
The present invention relates to a noise reduction apparatus and a noise reduction method.
With the development of science and technology and the wide use of multimedia devices, people are facing serious pollution problems while enjoying all kinds of convenience brought by modern science and technology. Noise is one of the major pollution sources among the above that is harmful to people's physical and mental health. On many occasions, such as the industrial production process, daily life and working environment, laboratory environment, etc., sound noise or even serious noise usually exists. It is harmful for long-term and close contact workers to their physical and mental health including hearing loss, fatigue, and attention loss. Therefore, there is a strong demand for noise reduction in situations that noise is more and more serious while people are increasingly pursuing physical and mental health for life quality.
In any acoustic system, noise control should be carried out through the source, the transmission path, or the receiver. Currently, noise reduction methods mainly comprise passive noise reduction method and active noise reduction method.
Passive noise reduction involves approaches of shock absorption, sound absorption, and sound insulation, which separates the external noise from the ear based on physical properties and usually insulates noise with sound-insulating materials. It is very effective for high-frequency noise and is typically reduced by about 15-20dB. The passive noise reduction method is simple in principle and low in cost but poor in effect. Generally, high-density acoustical insulation or headphone is used need which may result in uncomfortable. Passive noise reduction has a good effect on isolating high-frequency noise like acoustic panels near roads, but less effect on low-frequency noise in small spaces like air conditioner noise, projector noise, engine noise, sound of rain, sound of wind, sound of wave, sound of cicadas , etc.
The active noise reduction is based on the principle of two sound wave acoustic destructive interference or acoustic radiation suppression, comprising an artificially manufactured controlled sound source (secondary sound source) generating signals that are equal in value and opposite in phase with the original noise source (primary sound source) so that counterbalances mutually, thereby the purpose of noise reduction is achieved.
The object of the present invention is to provide a noise reduction apparatus and a noise reduction method for reducing undesired noise in the object area by signal processing, audio processing, and noise control.
To obtain one or more of these objects, the present invention provides a noise reduction apparatus comprising a microphone unit for real-time monitoring the environmental noise and generating an anti-noise signal-N1; a filtering unit for compensating the frequency characteristics of the anti-noise signal-N1 to-N2; a carrier loading unit for loading the compensated signal-N2 onto a high-frequency carrier C so as to form an envelope signal-N3 provided with opposite phase to the noise signal N1; an amplifier unit for amplifying the value of the envelope signal -N3 to -N4 provided with the same value of the noise signal N1; and a speaker unit for playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise.
Preferably, the microphone unit comprises a reverse microphone component.
Preferably, comprising a carrier generation unit for generating the high-frequency carrier C.
Preferably, the frequency of the high-frequency carrier C is higher than the upper limit of the human hearing frequency.
Preferably, comprising a comparator unit for comparing the value of the envelope signal-N3 and the noise signal N1, thereby the amplifier unit adjusting the value of the envelope signal-N3.
Preferably, the filtering unit removes the high-frequency part beyond the upper limit of the human hearing frequency from the anti-noise signal-N1.
Preferably, the filtering unit further comprising power supply components of a resistor R1 and a voltage source VDC which are connected with the microphone unit; impedance matching components of a capacitor C1 for removing the direct current part from the anti-noise signal input by the microphone unit; low-pass filtering components of R2, R3, C2, and C3 composing a second-order low-pass filter for removing the high-frequency part from the output signal of the impedance matching components and preserving the low-frequency part of the anti-noise signal.
According to another aspect, the present invention provides a noise reduction method comprising the steps of S1: real-time monitoring the environmental noise and generating an anti-noise signal-N1; S2: removing the high-frequency part beyond the upper limit of the human hearing frequency from the anti-noise signal-N1 and matching the impedance with the output to compensate the frequency characteristics to-N2; S3: loading the compensated signal-N2 onto a high-frequency carrier C provided with higher frequency than the upper limit of the human hearing so as to form an envelope signal-N3 provided with opposite phase to the noise signal N1; S4: amplifying the value of the envelope signal -N3 to -N4 provided with the same value of the noise signal N1; S5: playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise.
According to yet another aspect, the present invention provides a multimedia device, comprising the noise reduction apparatus according to the above.
Preferably, comprising any of the mobile phone, the tablet computer, the notebook computer, the desktop computer, and the all-in-one computer.
With the above-mentioned technical proposals, the advantages of the present invention is that,
1, in a noisy environment, a relatively quiet environment can be created by using devices such as laptops, mobile phones, all-in-one computers, or tablets;
2, under the active noise reduction control, undesired sound waves are destructively interfered to greatly reduce undesired noise;
3, a three-dimensional low noise region at a certain position can be created with the anti-noise signal output by the speaker.
Other aspects and advantages of the present invention will become clear from the following detailed description taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.
Figure 1 is a block diagram of the noise reduction apparatus according to the present invention.
Figure 2 is a schematic diagram of the noise reduction apparatus according to the present invention.
Figure 3 is a circuit diagram of the filtering unit of the noise reduction apparatus according to the present invention.
Figure 4 is a flow chart of the noise reduction method according to the present invention.
Figure 5 is an oscillogram showing the phase of the input signal and output signal of different types of the microphone unit.
Figure 6 is an oscillogram showing the signal before and after the carrier loading unit.
The detailed description of the preferred embodiment according to the invention is given below with the accompanying drawings so that the benefits and features of the present invention are understood for those skilled in the art.
The present embodiment discloses a noise reduction apparatus, which can be applied to such multimedia devices as mobile phones, tablets, notebooks, desktop computers, and all-in-one computers. The existing noise reduction method is mainly based on the active noise reduction technology eliminating the remote signal noise during a voice call. The environmental noise cannot be reduced due to the fact that only the voice noise during the call can be reduced. The purpose of the scheme is to reduce the undesired environmental noise in the object area by signal processing, audio processing, and noise control, thereby reducing the harm of the environmental noise to the physiology and mental health of people.
Figure 1 is a block diagram of the noise reduction apparatus according to the present invention. Figure 2 is a schematic diagram of the noise reduction apparatus according to the present invention. The present embodiment discloses a noise reduction apparatus comprising a microphone unit for real-time monitoring the environmental noise and generating an anti-noise signal-N1; a filtering unit for compensating the frequency characteristics of the anti-noise signal-N1 to-N2; a carrier loading unit for loading the compensated signal-N2 onto a high-frequency carrier C so as to form an envelope signal-N3 provided with opposite phase to the noise signal N1; an amplifier unit for amplifying the value of the envelope signal -N3 to -N4 provided with the same value of the noise signal N1; and a speaker unit for playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise. Communication channel1 can be wireless, while communication channel2 can be wire or PCB wire.
A comparator unit can be arranged before the amplifier unit which compares the value of the envelope signal-N3 and the noise signal N1, thereby the amplifier unit adjusts the value of the envelope signal-N3. The filtering unit removes the high-frequency part beyond the upper limit of the human hearing frequency from the anti-noise signal-N1. The reason for this is that the high-frequency part of the environmental noise higher than the upper limit of the human hearing frequency does not affect human hearing, so it is not necessary to perform noise reduction treatment on this part but make the noise reduction easier.
The high-frequency carrier C is generated by a carrier generation unit. The frequency of the high-frequency carrier C is higher than the upper limit of the human hearing frequency, because that no audible noise can be produced during the noise reduction process.
Figure 3 is a circuit diagram of the filtering unit of the noise reduction apparatus according to the present invention. The filtering unit further comprising the power supply components, the impedance matching components, and the low-pass filtering components. The power supply components are consist of a resistor R1 and a voltage source VDC which are connected with the microphone unit. The impedance matching components are consist of a capacitor C1 for removing the direct current part from the anti-noise signal input by the microphone unit. The low-pass filtering components are consist of R2, R3, C2, and C3 composing a second-order low-pass filter for removing the high-frequency part from the output signal of the impedance matching components and preserving the low-frequency part of the anti-noise signal.
Figure 4 is a flow chart of the noise reduction method according to the present invention. The present embodiment discloses a noise reduction method comprising the steps of,
S1: a reverse microphone component real-time monitoring the environmental noise and generating an anti-noise signal-N1;
S2: removing the high-frequency part beyond the upper limit of the human hearing frequency from the anti-noise signal-N1 and matching the impedance with the output to compensate the frequency characteristics to-N2;
S3: loading the compensated signal-N2 onto a high-frequency carrier C provided with higher frequency than the upper limit of the human hearing so as to form an envelope signal-N3 provided with opposite phase to the noise signal N1;
S4: amplifying the value of the envelope signal -N3 to -N4 provided with same value of the noise signal N1;
S5: playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise.
With the above-mentioned technical proposals, the advantages of the present noise reduction method are that,
1, In a noisy environment, a relatively quiet environment can be created by using devices such as laptops, mobile phones, all-in-one computers, or tablets;
2, Under the active noise reduction control, undesired sound waves are destructively interfered to greatly reduce undesired noise;
3, A three-dimensional low noise region at a certain position can be created with the anti-noise signal output by the speaker.
Figure 5 is an oscillogram showing the phase of the input signal and output signal of different types of the microphone unit. The output signal of a microphone is provided with the same phase of the input signal, while the output signal of a reverse microphone is provided with the opposite phase of the input signal. The present embodiment takes the reverse microphone that has the opposite phase of the input signal. In this case, the output signal is opposite in phase with the input signal (i.e., 180 degrees). The microphone unit receives the external noise and outputs a microphone signal (MIC +, MIC-) with reverted output characteristics of the received external noise. In other words, the microphone receives an input signal (e.g., external noise) and outputs an output signal (e.g., reverse noise) that is opposite in phase with the input signal, and the speaker unit outputs the reverse audio signal (Audio +, Audio-).
Figure 6 is an oscillogram showing the signal before and after the carrier loading unit. The environmental noise is acquired by the microphone component to generate an anti-noise signal-N1 which is compensated to form a signal -N2 by the filtering unit. The compensated signal-N2 is loaded onto a high-frequency carrier C to form an envelope signal-N3 provided with the opposite phase to the noise signal N1.
The above descriptions are meant to be exemplary only and are not limited to the examples shown in the drawings and described hereinbefore, and those skilled in the art will recognize that changes may be made to the embodiments described without department from the scope of the invention disclosed. Still, other modifications varied in efficient manners within the scope of the present invention, and their technical equivalents will be apparent to those skilled in the art, in light of a review of this disclosure, and such modifications are intended to fall within the appended claims.

Claims (10)

  1. A noise reduction apparatus, characterized by comprising
    a microphone unit for real-time monitoring the environmental noise and generating an anti-noise signal-N1;
    a filtering unit for compensating the frequency characteristics of the anti-noise signal-N1 to-N2;
    a carrier loading unit for loading the compensated signal-N2 onto a high-frequency carrier C so as to form an envelope signal-N3 provided with opposite phase to the noise signal N1;
    an amplifier unit for amplifying the value of the envelope signal -N3 to -N4 provided with the same value of the noise signal N1; and
    a speaker unit for playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise.
  2. The noise reduction apparatus according to claim 1, wherein the microphone unit comprises a reverse microphone component.
  3. The noise reduction apparatus according to claim 1, wherein comprising a carrier generation unit for generating the high-frequency carrier C.
  4. The noise reduction apparatus according to claim 3, wherein the frequency of the high-frequency carrier C is higher than the upper limit of the human hearing frequency.
  5. The noise reduction apparatus according to claim 1, wherein comprising a comparator unit for comparing the value of the envelope signal-N3 and the noise signal N1, thereby the amplifier unit adjusting the value of the envelope signal-N3.
  6. The noise reduction apparatus according to claim 1, wherein: the filtering unit removes the high-frequency part beyond the upper limit of the human hearing frequency from the anti-noise signal-N1.
  7. The noise reduction apparatus according to claim 6, wherein, the filtering unit further comprising
    power supply components of a resistor R1 and a voltage source VDC which are connected with the microphone unit;
    impedance matching components of a capacitor C1 for removing the direct current part from the anti-noise signal input by the microphone unit;
    low-pass filtering components of R2, R3, C2, and C3 composing a second-order low-pass filter for removing the high-frequency part from the output signal of the impedance matching components and preserving the low-frequency part of the anti-noise signal.
  8. A noise reduction method, characterized by comprising the steps of
    S1: real-time monitoring the environmental noise and generating an anti-noise signal-N1;
    S2: removing the high-frequency part beyond the upper limit of the human hearing frequency from the anti-noise signal-N1 and matching the impedance with the output to compensate the frequency characteristics to-N2;
    S3: loading the compensated signal-N2 onto a high-frequency carrier C provided with higher frequency than the upper limit of the human hearing so as to form an envelope signal-N3 provided with opposite phase to the noise signal N1;
    S4: amplifying the value of the envelope signal -N3 to -N4 provided with the same value of the noise signal N1;
    S5: playing the amplified signal-N4 output by the amplifier unit so as to reduce the environmental noise.
  9. A multimedia device, characterized by comprising the noise reduction apparatus according to any of claims 1 to 7.
  10. The multimedia device according to claim 9, wherein comprising any of the mobile phone, the tablet computer, the notebook computer, the desktop computer, and the all-in-one computer.
PCT/KR2022/011992 2021-08-20 2022-08-11 Noise reduction apparatus, noise reduction method, and multimedia device WO2023022435A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202110961235.7A CN113781991A (en) 2021-08-20 2021-08-20 Noise reduction device, noise reduction method and multimedia equipment
CN202110961235.7 2021-08-20

Publications (1)

Publication Number Publication Date
WO2023022435A1 true WO2023022435A1 (en) 2023-02-23

Family

ID=78838325

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/KR2022/011992 WO2023022435A1 (en) 2021-08-20 2022-08-11 Noise reduction apparatus, noise reduction method, and multimedia device

Country Status (2)

Country Link
CN (1) CN113781991A (en)
WO (1) WO2023022435A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113781991A (en) * 2021-08-20 2021-12-10 苏州三星电子电脑有限公司 Noise reduction device, noise reduction method and multimedia equipment

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030185405A1 (en) * 1999-08-26 2003-10-02 Spencer Michael E. Modulator processing for a parametric speaker system
JP2005352255A (en) * 2004-06-11 2005-12-22 Seiko Epson Corp Noise eliminating device, sound reproduction system,and noise eliminating method
KR100788678B1 (en) * 2006-01-14 2007-12-26 삼성전자주식회사 Apparatus and method for reducing noise of earphone
US20090214049A1 (en) * 2008-02-22 2009-08-27 National Taiwan University Electrostatic Loudspeaker Array
CN113781991A (en) * 2021-08-20 2021-12-10 苏州三星电子电脑有限公司 Noise reduction device, noise reduction method and multimedia equipment

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005331571A (en) * 2004-05-18 2005-12-02 Seiko Epson Corp Electronic silencing system and silencing method
US9368098B2 (en) * 2013-10-11 2016-06-14 Turtle Beach Corporation Parametric emitter system with noise cancelation
CN112216264A (en) * 2020-09-11 2021-01-12 深圳拓邦股份有限公司 Sweeper noise reduction method and device, sweeper and computer readable storage medium
CN112669807A (en) * 2020-12-29 2021-04-16 复旦大学 Noise directional active control method
CN113112982B (en) * 2021-04-13 2022-08-16 上海联影医疗科技股份有限公司 Medical equipment, noise reduction method of medical equipment and storage medium

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030185405A1 (en) * 1999-08-26 2003-10-02 Spencer Michael E. Modulator processing for a parametric speaker system
JP2005352255A (en) * 2004-06-11 2005-12-22 Seiko Epson Corp Noise eliminating device, sound reproduction system,and noise eliminating method
KR100788678B1 (en) * 2006-01-14 2007-12-26 삼성전자주식회사 Apparatus and method for reducing noise of earphone
US20090214049A1 (en) * 2008-02-22 2009-08-27 National Taiwan University Electrostatic Loudspeaker Array
CN113781991A (en) * 2021-08-20 2021-12-10 苏州三星电子电脑有限公司 Noise reduction device, noise reduction method and multimedia equipment

Also Published As

Publication number Publication date
CN113781991A (en) 2021-12-10

Similar Documents

Publication Publication Date Title
KR101500823B1 (en) Method and device for speech enhancement, and communication headphones with noise reduction
CN108076419B (en) Linear resonant actuator controller
US9402132B2 (en) Limiting active noise cancellation output
CN105959842A (en) Earphone noise reduction processing method and device, and earphone
CN105979415A (en) Noise reduction method capable of realizing self-adaptive adjustment of noise reduction gain, device thereof, and noise reduction earphone
KR20130101152A (en) Communication headset speech enhancement method and device, and noise reduction communication headset
CN111681633B (en) Noise control device, electrical equipment and noise control method thereof
EP2790417A1 (en) Earhole attachment-type sound pickup device, signal processing device, and sound pickup method
WO2023022435A1 (en) Noise reduction apparatus, noise reduction method, and multimedia device
CN206713019U (en) Active noise reducing device and earphone
WO2021238354A1 (en) Sound leakage canceling method and electronic device
WO2011079722A1 (en) Nonenveloped earplug type earphone, device and method for enhancing sound at its earpiece
CN103873975A (en) Bluetooth headset noise reduction method, device and system
CN101924967A (en) Noise reduction earphone and method for reducing noises and distortion of same
CN103686555A (en) Miniature loudspeaker module group and method for enhancing frequency response of miniature loudspeaker module group, and electronic device
CN102238452A (en) Method for actively resisting noises in hands-free earphone and hands-free earphone
WO2020076013A1 (en) Mobile platform based active noise cancellation (anc)
WO2023098401A1 (en) Earphone having active noise reduction function and active noise reduction method
US20090029733A1 (en) Method and apparatus for controllable filtering on multiplexed data bus ports
CN201438738U (en) Active noise cancellation system
KR20140006394A (en) Noise reduction processing device of earphone and headphone.
CN103634731A (en) Method for adjusting loudspeaker, and electronic device
CN105263081A (en) Feedback-suppressed earplug device
CN201717926U (en) Active denoising system
CN115190388A (en) Earphone interface circuit and electronic equipment

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22858673

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE