WO2016067540A1 - 信号処理装置、プログラム、レンジフード装置、および信号処理装置における周波数ビンの選択方法 - Google Patents
信号処理装置、プログラム、レンジフード装置、および信号処理装置における周波数ビンの選択方法 Download PDFInfo
- Publication number
- WO2016067540A1 WO2016067540A1 PCT/JP2015/005208 JP2015005208W WO2016067540A1 WO 2016067540 A1 WO2016067540 A1 WO 2016067540A1 JP 2015005208 W JP2015005208 W JP 2015005208W WO 2016067540 A1 WO2016067540 A1 WO 2016067540A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- frequency
- noise
- sound
- filter coefficient
- signal processing
- Prior art date
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24C—DOMESTIC STOVES OR RANGES ; DETAILS OF DOMESTIC STOVES OR RANGES, OF GENERAL APPLICATION
- F24C15/00—Details
- F24C15/20—Removing cooking fumes
- F24C15/2021—Arrangement or mounting of control or safety systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24C—DOMESTIC STOVES OR RANGES ; DETAILS OF DOMESTIC STOVES OR RANGES, OF GENERAL APPLICATION
- F24C15/00—Details
- F24C15/20—Removing cooking fumes
- F24C15/2042—Devices for removing cooking fumes structurally associated with a cooking range e.g. downdraft
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F7/00—Ventilation
- F24F7/04—Ventilation with ducting systems, e.g. by double walls; with natural circulation
- F24F7/06—Ventilation with ducting systems, e.g. by double walls; with natural circulation with forced air circulation, e.g. by fan positioning of a ventilator in or against a conduit
-
- 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
- G10K11/17825—Error signals
-
- 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
- G10K11/17854—Methods, e.g. algorithms; Devices of the filter the filter being an adaptive 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
- G10K11/1785—Methods, e.g. algorithms; Devices
- G10K11/17855—Methods, e.g. algorithms; Devices for improving speed or power requirements
-
- 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
- G10K11/17879—General system configurations using both a reference signal and an error signal
- G10K11/17881—General system configurations using both a reference signal and an error signal the reference signal being an acoustic signal, e.g. recorded with a microphone
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
- F24F2013/247—Active noise-suppression
-
- 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
- G10K2210/105—Appliances, e.g. washing machines or dishwashers
-
- 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
- G10K2210/109—Compressors, e.g. fans
-
- 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
- G10K2210/301—Computational
- G10K2210/3025—Determination of spectrum characteristics, e.g. FFT
-
- 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
- G10K2210/301—Computational
- G10K2210/3028—Filtering, e.g. Kalman filters or special analogue or digital filters
-
- 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
- G10K2210/301—Computational
- G10K2210/3055—Transfer function of the acoustic system
Definitions
- the present invention generally relates to a signal processing device, a program, a range hood device, and a frequency bin selection method in the signal processing device, and more specifically, a signal processing device, program, range hood device, and signal processing for performing active noise control.
- the present invention relates to a method for selecting a frequency bin in an apparatus.
- a silencer using active noise control as a technique for reducing noise in a space (noise propagation path) through which sound emitted from a noise source propagates.
- Active noise control is a technique for actively reducing noise by radiating a cancellation sound having the opposite phase and the same amplitude.
- the transfer characteristic from the speaker to the error microphone has a peak band where the gain increases and a notch band where the gain falls, which has an adverse effect on the silencing effect. Therefore, there is a demand for active noise control capable of obtaining an excellent silencing effect even when the notch band and the peak band exist in the transfer characteristics from the speaker to the error microphone.
- the present invention has been made in view of the above-mentioned reasons, and the object thereof is to reduce the load caused by the filter coefficient calculation processing, and further, the peak band and the notch band are included in the transfer characteristic from the speaker to the error microphone.
- An object of the present invention is to provide a signal processing device, a program, a range hood device, and a method for selecting a frequency bin in a signal processing device that can obtain an excellent silencing effect even if it exists.
- the signal processing apparatus includes a first sound input device that collects the first noise and is provided in a space in which the first noise emitted from a noise source propagates, and the first noise that is input with a cancel signal. Used in combination with a sound input / output device including a sound output device that emits a canceling sound to cancel the sound into the space, and a second sound input device that collects a synthesized sound of the first noise and the canceling sound in the space.
- a silence filter in which a filter coefficient is set for each of a plurality of frequency bins obtained by dividing a predetermined frequency band, and a noise signal generated based on the output of the first sound input device is input.
- a cancel signal generating unit that outputs the cancel signal, and the filter in the process of repeatedly calculating the output of the first sound input device, the output of the second sound input device, and the filter coefficient
- a coefficient updating unit that calculates the filter coefficient of each of the plurality of frequency bins based on an update parameter related to the magnitude of the number of correction amounts; and a parameter that sets the update parameter of each of the plurality of frequency bins
- the parameter setting unit includes a first frequency bin corresponding to a frequency band of the first noise among the plurality of frequency bins, and a first frequency bin different from the first noise among the plurality of frequency bins.
- the update parameter is set so that the filter coefficient can be corrected, and any one of the first noise and the second noise among the plurality of frequency bins is set. Notch in which the transfer characteristic of the acoustic path from the sound output device to the second sound input device falls among frequency bins not corresponding to the frequency band of For the third frequency bins of frequency, and sets the updated parameter so as not to correct the filter coefficient.
- the program of the present invention is characterized by causing a computer to function as a signal processing device.
- a range hood device collects a hollow air passage, a fan that generates an air flow from one end of the air passage toward the other end, and a first noise that is provided in the air passage and is emitted from the fan.
- a first sound input device that receives the cancel signal, and a sound output device that emits a cancel sound that cancels the first noise into the air passage, and a synthesis of the first noise and the cancel sound in the air passage
- a second sound input device that collects sound, and the signal processing device according to any one of claims 1 to 3, wherein the second sound input device, The sound output device and the first sound input device are arranged in this order.
- the method for selecting frequency bins in the signal processing device of the present invention is a method for selecting frequency bins in the signal processing device, wherein the filter coefficient is selected from the frequency bins not corresponding to the frequency band of the first noise emitted from the noise source.
- a frequency bin in which the gain by the filter coefficient when the update parameter that cannot correct the filter coefficient is set is larger than the gain by the filter coefficient when the update parameter that can correct the filter coefficient is set,
- the frequency bin whose group delay amount of the transfer characteristic of the acoustic path from the sound output device to the second sound input device is lower than a threshold is selected from It is characterized by setting to 3 frequency bins.
- the frequency bin selection method in the signal processing device, program, range hood device, and signal processing device of the present invention has an effect of reducing the load caused by the filter coefficient calculation processing. Furthermore, in the signal processing device, the program, the range hood device, and the signal processing device according to the present invention, the frequency bin selection method may include a peak band and a notch band in the transfer characteristics from the speaker to the error microphone. There is an effect that an excellent silencing effect can be obtained.
- FIG. 1 is a block diagram illustrating the configuration of the first embodiment.
- FIG. 2 is a perspective view illustrating an appearance of the range hood device according to the first embodiment.
- FIG. 3 is a graph showing the silencing characteristics during the partial update process of the first embodiment.
- FIG. 4 is a graph (a) showing the gain of the transfer characteristic C of the first embodiment and a graph (b) showing the group delay amount of the transfer characteristic C of the first embodiment.
- FIG. 5 is a graph illustrating an example of the filter coefficient according to the first embodiment.
- FIG. 6 is a graph showing the silencing characteristics at the time of all update processing according to the first embodiment.
- FIG. 7 is an explanatory diagram illustrating processing of the signal processing device according to the first embodiment.
- FIG. 1 is a block diagram illustrating the configuration of the first embodiment.
- FIG. 2 is a perspective view illustrating an appearance of the range hood device according to the first embodiment.
- FIG. 3 is a graph showing the silencing characteristics during the partial update
- FIG. 8 is a graph showing the silencing characteristics of the signal processing apparatus according to the first embodiment.
- FIG. 9 is a block diagram illustrating a configuration of the second embodiment.
- FIG. 10 is a graph showing the temperature variation of the transfer characteristic C of the second embodiment.
- FIG. 11 is a block diagram illustrating a configuration of the third embodiment.
- FIG. 12 is a flowchart showing a method for selecting a frequency bin.
- FIG. 1 shows a configuration of a silencer 1 (active noise control device) of the present embodiment, and the range hood device 2 includes the silencer 1.
- the range hood apparatus 2 includes a duct 21 (ventilation path) disposed above a kitchen appliance in the kitchen.
- the duct 21 is formed in a box shape in which an air inlet 21a is provided on the lower surface, and the duct 21 includes a fan 22 (see FIG. 1) that takes indoor air into the duct 21 from the air inlet 21a and exhausts the air outside.
- a rectifying plate 23 is provided in the intake port 21a.
- the rectifying plate 23 is formed slightly smaller than the intake port 21a, and improves the intake efficiency.
- the operation part 24 is provided in the front surface of the range hood apparatus 2, and the operation part 24 is provided with the operation switch of each operation
- the space in the duct 21 constituting the air passage corresponds to a space where noise propagates.
- the fan 22 When the fan 22 operates, the fan 22 becomes a noise source, and the operation sound (first noise) of the fan 22 propagates through the duct 21 and is transmitted from the air inlet 21a to the room. Therefore, the silencer 1 is provided in the duct 21 in order to suppress noise transmitted to the room during the operation of the fan 22.
- the silencer 1 provided in the duct 21 includes a sound input / output device 11 and a signal processing device 12, as shown in FIG.
- the sound input / output device 11 includes a reference microphone 111 (first sound input device), an error microphone 112 (second sound input device), and a speaker (sound output device) 113.
- the reference microphone 111 is located on the fan 22 side in the duct 21.
- the error microphone 112 is located on the inlet 21 a side in the duct 21.
- the speaker 113 is located between the reference microphone 111 and the error microphone 112 in the duct 21. That is, the reference microphone 111, the speaker 113, and the error microphone 112 are arranged in this order from the fan 22 to the air inlet 21a.
- the signal processing device 12 includes amplifiers 121, 122, 123, A / D converters 124, 125, a D / A converter 126, and a mute control block 127.
- the output of the reference microphone 111 is amplified by the amplifier 121 and then A / D converted by the A / D converter 124.
- the output of the A / D converter 124 is input to the mute control block 127.
- the output of the error microphone 112 is amplified by the amplifier 122 and then A / D converted by the A / D converter 125.
- the output of the A / D converter 125 is input to the mute control block 127.
- the cancellation signal output from the silence control block 127 is D / A converted by the D / A converter 126 and then amplified by the amplifier 123.
- the speaker 113 receives the cancel signal amplified by the amplifier 123 and emits a cancel sound.
- the silencing control block 127 is composed of a computer that executes a program. Then, the mute control block 127 causes the speaker 113 to output a cancel sound that cancels the first noise generated by the fan 22 so that the sound pressure level at the installation point (mute point) of the error microphone 112 is minimized. That is, when the speaker 113 outputs a canceling sound, the first noise transmitted from the fan 22 to the outside of the duct 21 through the air inlet 21a is suppressed.
- the silencing control block 127 performs active noise control, and executes a silencing program that realizes the function of an adaptive filter in order to follow changes in noise and noise propagation characteristics of the fan 22 serving as a noise source. For updating the filter coefficient of the adaptive filter, a Filtered-X LMS (Least Mean ⁇ Square) sequential update control algorithm is used.
- the reference microphone 111 collects the first noise that is noise from the fan 22, and outputs a noise signal including the collected first noise to the signal processing device 12.
- the A / D converter 124 outputs a discrete value obtained by A / D converting the noise signal amplified by the amplifier 121 at a predetermined sampling frequency to the mute control block 127.
- the error microphone 112 collects residual noise that could not be erased by the cancellation sound at the silencing point, and outputs an error signal corresponding to the collected residual noise to the signal processing device 12.
- the A / D converter 125 performs silence control using a discrete value obtained by A / D converting the error signal amplified by the amplifier 122 at the same sampling frequency as that of the A / D converter 124 as a time domain error signal e (t). Output to block 127.
- the mute control block 127 includes a howling cancellation filter 131 (Howling Cancel Filter), a subtractor 132, a first signal conversion unit 133, a second signal conversion unit 134, a coefficient update unit 135, a cancellation signal generation unit 136, and a parameter setting unit 137.
- the first signal conversion unit 133 includes a correction filter 133a and a conversion unit 133b.
- the second signal conversion unit 134 includes a conversion unit 134a.
- the coefficient update unit 135 includes a coefficient adjustment unit 135a and an inverse conversion unit 135b.
- the cancel signal generation unit 136 includes a silence filter 136a and an inverter 136b.
- the howling cancellation filter 131 is an FIR filter (Finite Impulse Response Filter) in which a transfer characteristic F ⁇ simulating the transfer characteristic F of sound waves from the speaker 113 to the reference microphone 111 is set as a filter coefficient.
- FIR filter Finite Impulse Response Filter
- This howling cancel filter 131 performs a convolution operation on the transfer characteristic F ⁇ on the cancel signal Y (t) output from the cancel signal generation unit 136.
- the subtractor 132 outputs a signal obtained by subtracting the output of the howling cancellation filter 131 from the output of the A / D converter 124. That is, a signal obtained by subtracting the wraparound component of the canceling sound from the noise signal collected by the reference microphone 111 is output from the subtractor 132 as the noise signal X (t). Therefore, even if the cancel sound emitted from the speaker 113 wraps around the reference microphone 111, occurrence of howling can be prevented.
- the output of the subtracter 132 is input to the mute filter 136a and the correction filter 133a.
- the muffler filter 136a is an FIR type adaptive filter in which the filter coefficient W (t) is set by the coefficient updating unit 135.
- filter coefficients W1 (t) to Wn (t) are set for each of a plurality of frequency bins obtained by dividing the entire frequency band of the cancel sound into n.
- the filter coefficients W1 (t) to Wn (t) in the time domain are not distinguished, they are expressed as filter coefficients W (t).
- the number of frequency bins is set so that the frequency width of the frequency bin is, for example, several tens Hz to several hundreds Hz.
- the correction filter 133a is an FIR filter in which a transfer characteristic C ⁇ simulating the transfer characteristic C of a sound wave from the speaker 113 to the error microphone 112 is set as a filter coefficient.
- the correction filter 133a performs a convolution operation between the noise signal X (t) output from the subtractor 132 and the transfer characteristic C ⁇ , and the output of the correction filter 133a is converted into a time domain reference signal r (t) as a conversion unit. It is input to 133b.
- the conversion unit 133b converts the time domain reference signal r (t) into a frequency domain reference signal R ( ⁇ ) by FFT (Fast Fourier Transform). That is, the first signal conversion unit 133 outputs the frequency domain reference signal R ( ⁇ ) obtained by correcting the noise signal X (t) based on the transfer characteristic C ⁇ to the coefficient adjustment unit 135a.
- the conversion unit 134a of the second signal conversion unit 134 converts the time domain error signal e (t) into a frequency domain error signal E ( ⁇ ) by FFT. That is, the second signal conversion unit 134 outputs the frequency domain error signal E ( ⁇ ) to the coefficient adjustment unit 135a.
- the coefficient adjusting unit 135a of the coefficient updating unit 135 updates the filter coefficients W1 ( ⁇ ) to Wn ( ⁇ ) of the muffler filter 136a using a well-known sequential update control algorithm called Filtered-X LMS in the frequency domain.
- the coefficient adjustment unit 135a receives the reference signal R ( ⁇ ) and the error signal E ( ⁇ ), and further sets the update parameter ⁇ by the parameter setting unit 137, so that the filter coefficients W1 ( ⁇ ) to Wn of the silence filter 136a are set. ( ⁇ ) is calculated.
- the frequency domain filter coefficients W1 ( ⁇ ) to Wn ( ⁇ ) are not distinguished, they are represented as filter coefficients W ( ⁇ ).
- the filter coefficient W (t) in the time domain and the filter coefficient W ( ⁇ ) in the frequency domain are not distinguished, they are expressed as filter coefficients W.
- the filter coefficient W ( ⁇ ) is updated so that the error signal E ( ⁇ ) is minimized.
- the update processing of the filter coefficient W ( ⁇ ) is expressed by the following formula 1 when the filter coefficient is W ( ⁇ ), the update parameter is ⁇ , and the sample number is m.
- the update parameter ⁇ is also called a step size parameter, and is a parameter that determines the magnitude of the correction amount of the filter coefficient W ( ⁇ ) in the process of repeatedly calculating the filter coefficient W ( ⁇ ) using the LMS algorithm or the like.
- the convergence time of the filter coefficient W ( ⁇ ) depends on the size of the reference signal R ( ⁇ ), the error signal E ( ⁇ ), and the update parameter ⁇ .
- the coefficient adjustment unit 135a adjusts the convergence time by multiplying the update parameter ⁇ in the process of calculating the filter coefficient W ( ⁇ ). In order to shorten the time required for convergence, it is necessary to increase the update parameter ⁇ . However, if the update parameter ⁇ is excessively increased, there is a possibility of divergence without convergence.
- the parameter setting unit 137 adjusts the convergence speed of each of the filter coefficients W1 ( ⁇ ) to Wn ( ⁇ ) for each frequency bin by setting update parameters ⁇ 1 to ⁇ n corresponding to each of the plurality of frequency bins. To do.
- the parameter setting unit 137 delivers each value of the update parameters ⁇ 1 to ⁇ n to the coefficient adjustment unit 135a.
- update parameters ⁇ 1 to ⁇ n are not distinguished, they are represented as update parameters ⁇ .
- the coefficient adjustment unit 135a receives the frequency domain reference signal R ( ⁇ ) and the frequency domain error signal E ( ⁇ ), and the parameter setting unit 137 updates the update parameters ⁇ 1 to ⁇ n used in the LMS algorithm for each frequency bin. Is set. Then, the coefficient adjustment unit 135a executes a Filtered-X LMS algorithm in the frequency domain (see Equation 1), and calculates and outputs filter coefficients W1 ( ⁇ ) to Wn ( ⁇ ) for each frequency bin. Therefore, the signal processing device 12 can realize accurate filter characteristics by setting the filter coefficients W1 ( ⁇ ) to Wn ( ⁇ ) for each frequency bin.
- the inverse transform unit 135b performs inverse FFT (Inverse Fast Fourier Transform), thereby converting the frequency domain filter coefficients W1 ( ⁇ ) to Wn ( ⁇ ) calculated by the coefficient adjustment unit 135a into time domain filter coefficients W1 (t ) To Wn (t).
- the filter coefficients W1 (t) to Wn (t) for each frequency bin of the silence filter 136a are set by the output of the inverse transform unit 135b.
- the coefficient updating unit 135 sequentially updates the filter coefficients W1 (t) to Wn (t) of the mute filter 136a.
- the silencing filter 136a separates the noise signal X (t) for each frequency bin, and performs a convolution operation between the noise signal X (t) and the filter coefficients W1 (t) to Wn (t) for each frequency bin.
- the silence filter 136a then outputs the sum of the results of the convolution operation performed for each frequency bin.
- the cancel signal Y (t) is generated by inverting the phase of the output of the muffler filter 136a by the inverter 136b.
- the cancel signal Y (t) output from the cancel signal generation unit 136 is D / A converted by the D / A converter 126 and then amplified by the amplifier 123, and a cancel sound is output from the speaker 113.
- the waveform of the cancellation sound (cancellation signal Y (t)) is generated so as to have the opposite phase and the same amplitude as the noise waveform at the silencing point, and is propagated from the fan 22 through the duct 21 and discharged from the intake port 21a.
- the first noise is reduced.
- Update processing of the filter coefficient W ( ⁇ ) is performed by the coefficient adjustment unit 135a.
- the filter coefficient W ( ⁇ ) is updated by the coefficient adjustment unit 135a.
- the process of updating the filter coefficient W ( ⁇ ) only in a part of the frequency band is referred to as a partial update process.
- the parameter setting unit 137 sets the update parameter ⁇ to a value larger than zero for the frequency bin 8 constituting the frequency band F1, and sets the filter coefficient W ( ⁇ ) by the coefficient adjustment unit 135a. Update process is executed. Also, the parameter setting unit 137 sets the update parameter ⁇ to zero for the frequency bins 9 constituting the frequency band F2, and does not execute the filter coefficient W ( ⁇ ) update process by the coefficient adjustment unit 135a.
- FIG. 3 shows the silencing characteristic
- the characteristic Y1 solid line
- the characteristic Y0 (broken line) indicates the sound pressure (amplitude) at the silencing point when the noise suppression processing by the silencing device 1 is not performed.
- the characteristic Y1 has a large silence volume in the frequency band F1, but the frequency band F21 in which the sound pressure is locally amplified occurs in the frequency band F2.
- This frequency band F21 corresponds to a frequency band in which the gain of the transfer characteristic C reaches a peak, and is hereinafter referred to as a peak band F21 (see (a) in FIG. 4).
- the filter coefficient W ( ⁇ ) is not updated by the coefficient adjustment unit 135a, and therefore the gain of the filter coefficient W ( ⁇ ) tends to increase.
- the silencing characteristic is like the characteristic Y1 in which the sound pressure is locally increased in the peak band F21.
- FIG. 5 shows the characteristics (filter characteristics) of the filter coefficient W ( ⁇ ).
- the filter characteristic Y11 solid line
- the filter characteristic Y12 broken line
- the filter characteristic Y11 does not perform the update process of the filter coefficient W ( ⁇ ) in the peak band F21
- the gain in the peak band F21 has a relatively high value. Since the filter characteristic Y12 updates the filter coefficient W ( ⁇ ) in the peak band F21, the gain in the peak band F21 is optimized.
- the gain of the filter characteristic Y11 is larger than the gain of the filter characteristic Y12. Since the cancel sound output from the speaker 113 is generated by a convolution operation of the noise signal X (t) and the filter coefficient W (t) (the result of applying inverse FFT to the filter coefficient W ( ⁇ )), the cancel sound Are locally amplified in the frequency band F21. Therefore, as for the silencing characteristic, a peak band F21 in which the sound pressure is locally amplified occurs in the frequency band F2, as the characteristic Y1 in FIG. The cancellation sound locally amplified in the peak band F21 becomes the second noise.
- the characteristic Y21 (solid line) indicates the sound pressure (amplitude) at the muffle point when the full update process is performed.
- the characteristic Y20 (broken line) indicates the sound pressure (amplitude) at the silencing point when the noise suppression processing by the silencing device 1 is not performed.
- the characteristic Y21 has a frequency band F22 that is locally amplified and oscillated in the frequency band F2.
- This frequency band F22 corresponds to a frequency band where the gain of the transfer characteristic C falls locally, and is hereinafter referred to as a notch band F22 (see FIG. 4A).
- a notch band F22 since the transfer characteristic C has a low gain and the phase fluctuates greatly, a characteristic error between the transfer characteristic C ⁇ set in the correction filter 133a and the actual transfer characteristic C is likely to occur. Thus, amplification and oscillation occur.
- FIG. 4B shows the group delay characteristic (phase component differential characteristic) of the transfer characteristic C. It can be seen that the phase fluctuates greatly in the notch band F22 and the group delay amount in the notch band F22 is large.
- the threshold D1 may be other than 0, and the value of the threshold D1 is set as appropriate.
- the signal processing device 12 performs the following processing.
- the parameter setting unit 137 sets the update parameter ⁇ to a value larger than zero for the frequency bin 8 (first frequency bin) constituting the frequency band F1 of the first noise generated by the fan 22. Set.
- the parameter setting unit 137 sets the update parameter ⁇ to a value larger than zero for the frequency bin 91 (second frequency bin) constituting the peak band F21 in the frequency band F2.
- the parameter setting unit 137 selects the frequency bin 92 (third frequency bin) constituting the notch band F22 as shown in FIG. 7 among the frequency bins 9 constituting the band other than the peak band F21 in the frequency band F2. Always sets the update parameter ⁇ to zero.
- the parameter setting unit 137 also updates the update parameter for the frequency bin 93 that does not constitute the notch band F22 as shown in FIG. 7 among the frequency bins 9 that constitute a band other than the peak band F21 in the frequency band F2.
- Set ⁇ to zero In the present embodiment, the update parameter ⁇ of the frequency bin 93 is set to zero, but the update parameter ⁇ of the frequency bin 93 may be set to a value larger than zero. That is, it is only necessary that the update parameter ⁇ is always set to zero for the frequency bins 92 constituting the notch band F22 among the frequency bins 9 constituting the band other than the peak band F21 in the frequency band F2.
- the parameter setting unit 137 sets the update parameter ⁇ of the frequency bin 8 constituting the frequency band F11 to a value greater than zero.
- each data of the peak band F21 and the notch band F22 used in the parameter setting unit 137 is set in advance based on the transfer characteristic C ⁇ set in the correction filter 133a.
- the frequency bins 91, 92, and 93 in the frequency band F2 are not distinguished, they are referred to as the frequency bin 9.
- the update parameter ⁇ is a value greater than zero, the second term on the right side of Equation 1 exceeds zero, and the filter coefficient W ( ⁇ ) is sequentially updated. If the update parameter ⁇ is set to zero, the second term on the right side of Equation 1 becomes zero, and the filter coefficient W ( ⁇ ) is not updated.
- the coefficient adjustment unit 135a executes the update process of the filter coefficient W ( ⁇ ) for the frequency bins 8 constituting the frequency band F1. Furthermore, the coefficient adjustment unit 135a also performs the update process of the filter coefficient W ( ⁇ ) for the frequency bin 91 that configures the peak band F21 in the frequency band F2.
- the coefficient adjustment unit 135a does not execute the update process of the filter coefficient W ( ⁇ ) for the frequency bins 92 and 93 that constitute bands other than the peak band F21 in the frequency band F2. That is, the filter coefficient W ( ⁇ ) update process is not executed for the frequency bins 92 constituting the notch band F22. Further, in the present embodiment, the filter coefficient W ( ⁇ ) update process is not executed for the frequency bins 93 that do not constitute the notch band F22.
- FIG. 8 shows the silencing characteristic
- the characteristic Y31 solid line
- the characteristic Y30 (broken line) indicates the sound pressure (amplitude) at the muffle point when the noise suppression process is not performed.
- amplification in the peak band F21 is suppressed, and amplification and oscillation do not occur in the notch band F22. Therefore, the signal processing device 12 of this embodiment can obtain an excellent silencing effect even when the peak band F21 and the notch band F22 exist in the transfer characteristic C from the speaker 113 to the error microphone 112.
- the coefficient adjustment unit 135a performs the update process of the filter coefficient W ( ⁇ ) only for the frequency bin 91 in the frequency band F2, and the filter coefficient W ( ⁇ ) for the frequency bins 92 and 93. Do not execute the update process. Therefore, the signal processing device 12 of the present embodiment performs the update process of the filter coefficient W ( ⁇ ) only for a part of the frequency bands among all frequency bands in which the cancellation sound can be generated. It is possible to reduce the load due to the calculation processing of W ( ⁇ ).
- the signal processing device 12 described above is combined with a sound input / output device 11 including a reference microphone 111 (first sound input device), a speaker (sound output device) 113, and an error microphone 112 (second sound input device).
- the reference microphone 111 is provided in a space (a space in the duct 21) where the first noise emitted from the fan 22 (noise source) propagates and collects the first noise.
- the speaker 113 emits a cancel sound to the space that cancels the first noise when the cancel signal is input.
- the error microphone 112 collects a synthesized sound of the first noise and the cancellation sound in the space.
- the signal processing device 12 includes a cancel signal generation unit 136, a coefficient update unit 135, and a parameter setting unit 137.
- the cancel signal generation unit 136 includes a silence filter 136a in which a filter coefficient W is set for each of a plurality of frequency bins obtained by dividing a predetermined frequency band.
- the cancellation signal generation unit 136 receives the noise signal X (t) generated based on the output of the reference microphone 111 and outputs a cancellation signal.
- the coefficient updating unit 135 calculates the filter coefficient W of each of the plurality of frequency bins based on the output of the reference microphone 111, the output of the error microphone 112, and the update parameter ⁇ .
- the parameter setting unit 137 sets the update parameter ⁇ for each of the plurality of frequency bins.
- the update parameter ⁇ is a parameter related to the magnitude of the correction amount of the filter coefficient W in the process of repeatedly calculating the filter coefficient W.
- the parameter setting unit 137 sets the update parameter ⁇ so that the filter coefficient W can be corrected for the frequency bin 8 (first frequency bin) corresponding to the frequency band of the first noise among the plurality of frequency bins. To do. Further, the parameter setting unit 137 can correct the filter coefficient W even for the frequency bin 91 (second frequency bin) corresponding to the frequency band of the second noise different from the first noise among the plurality of frequency bins. Set the update parameter ⁇ to. Further, the parameter setting unit 137 transmits the transfer characteristic C of the acoustic path from the speaker 113 to the error microphone 112 among the frequency bins 9 that do not correspond to the frequency bands of the first noise and the second noise among the plurality of frequency bins. The update parameter ⁇ is set so that the filter coefficient W is not corrected for the frequency bin 92 (third frequency bin) in the notch band F22 in which the drop occurs.
- the signal processing device 12 of the present embodiment can reduce the load due to the calculation processing of the filter coefficient W ( ⁇ ). Furthermore, the signal processing apparatus 12 of the present embodiment can obtain an excellent silencing effect even when the peak band F21 and the notch band F22 exist in the transfer characteristic C from the speaker 113 to the error microphone 112.
- FIG. 1A The configuration of the silencer 1A (active noise control device) of the present embodiment is shown in FIG.
- the same components as those of the silencer 1 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
- the silencer 1 ⁇ / b> A includes a temperature sensor 3 in the duct 21.
- the temperature sensor 3 measures the temperature in the duct 21 and outputs the measurement result.
- the signal processing device 12A of the silencer 1A includes a silence control block 127A, and the silence control block 127A further includes a data acquisition unit 141, a temperature information storage unit 142, and a characteristic setting unit 143.
- the transfer characteristic C and the transfer characteristic F vary depending on the temperature in the duct 21.
- FIG. 10 shows an example of the transfer characteristic C for each temperature in the duct 21, and the fluctuation range of the transfer characteristic C due to temperature change increases as the frequency increases.
- the transfer characteristic F varies depending on the temperature in the duct 21.
- the characteristics Y41, Y42, and Y43 are shown in order of increasing temperature in the duct 21.
- the silencer 1 ⁇ / b> A performs the following processing based on the measurement result of the temperature in the duct 21 by the temperature sensor 3.
- the data acquisition unit 141 acquires the measurement result (temperature data) of the temperature in the duct 21 from the temperature sensor 3, and outputs the temperature data to the parameter setting unit 137A and the characteristic setting unit 143.
- the temperature information storage unit 142 stores transfer characteristic C data corresponding to each of a plurality of temperatures and transfer characteristic F data corresponding to each of the plurality of temperatures. Then, the characteristic setting unit 143 reads the transfer characteristic C data and the transfer characteristic F data corresponding to the temperature data from the temperature information storage unit 142. The characteristic setting unit 143 sets the transfer characteristic C data read from the temperature information storage unit 142 in the correction filter 133 a, and sets the transfer characteristic F data read from the temperature information storage unit 142 in the howling cancel filter 131. Therefore, a transfer characteristic C corresponding to the temperature in the duct 21 is set in the correction filter 133a, and a transfer characteristic F corresponding to the temperature in the duct 21 is set in the howling cancellation filter 131.
- the transfer characteristic C ⁇ of the correction filter 133a and the transfer characteristic F ⁇ of the howling cancellation filter 131 are set appropriately. That is, the correction process by the correction filter 133a and the howling cancellation process by the howling cancellation filter 131 can suppress the influence of the temperature change.
- the parameter setting unit 137A reads the data of the transfer characteristic C corresponding to the temperature data from the temperature information storage unit 142.
- the parameter setting unit 137A refers to the transfer characteristic C data read from the temperature information storage unit 142 and identifies the peak band F21.
- the parameter setting unit 137A can identify the peak band F21 by performing a local maximum method for searching for a local maximum point of the transfer characteristic C, a differential operation, or the like in the frequency band F2.
- the parameter setting unit 137A sets the update parameter ⁇ to a value larger than zero for the frequency bin 91 that constitutes the peak band F21.
- the parameter setting unit 137A can accurately specify the peak band F21 in the frequency band F2 and appropriately select the frequency bin 91 even if the transfer characteristic C varies due to temperature change.
- the transfer characteristic C data stored in the temperature information storage unit 142 includes information on the group delay characteristic of the transfer characteristic C. Therefore, the parameter setting unit 137A can identify the notch band F22 with reference to the transfer characteristic C data read from the temperature information storage unit 142. Specifically, the parameter setting unit 137A sets the frequency band in which the group delay amount is lower than the threshold D1 in the frequency band F2 as the notch band F22 (see FIG. 4B). The parameter setting unit 137A always sets the update parameter ⁇ to zero for the frequency bin 92 that forms the notch band F22.
- the parameter setting unit 137A can accurately specify the notch band F22 in the frequency band F2 even if the transfer characteristic C varies due to a temperature change, and can appropriately select the frequency bin 92.
- the signal processing device 12A preferably includes the data acquisition unit 141 that acquires temperature data of the space (the space in the duct 21). Then, the parameter setting unit 137A selects the frequency bin 91 (second frequency bin) and the frequency bin 92 (third frequency bin) according to the temperature of the space.
- the signal processing device 12A can obtain a more excellent silencing effect even if the transfer characteristic C varies due to a temperature change.
- the parameter setting unit 137A sets the update parameter ⁇ to zero even for the frequency bin 93 that does not constitute the notch band F22 in the frequency band F2.
- the update parameter ⁇ of the frequency bin 93 may be set to a value larger than zero.
- FIG. 11 shows the configuration of the silencer 1B (active noise control device) of the present embodiment.
- the same components as those of the silencer 1 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
- the signal processing device 12B of the silencer 1B includes a silence control block 127B, and the silence control block 127B includes a bin setting unit 151.
- the bin setting unit 151 sets each of all the frequency bins 9 in the frequency band F2 to any one of the frequency bin 91, the frequency bin 92, and the frequency bin 93.
- the bin setting unit 151 instructs the parameter setting unit 137 to perform each of the above-described partial update processing and full update processing.
- the partial update process is executed by the parameter setting unit 137 setting the update parameter ⁇ to zero for all frequency bins 9 in the frequency band F2.
- the all update process is executed by the parameter setting unit 137 setting the update parameter ⁇ to a value greater than zero for all the frequency bins 9 in the frequency band F2.
- the bin setting unit 151 compares the filter coefficient W ( ⁇ ) during the partial update process with the filter coefficient W ( ⁇ ) during the full update process.
- the bin setting unit 151 sets a range in which the filter coefficient W ( ⁇ ) during the partial update process is larger than the filter coefficient W ( ⁇ ) during the full update process as the peak band F21 (see FIG. 5).
- the bin setting unit 151 sets the update parameter ⁇ to a value larger than zero for the frequency bin 91 that constitutes the peak band F21.
- the minimum bandwidth is determined in advance for the peak bandwidth, and the bin setting unit 151 has a minimum range in which the filter coefficient W ( ⁇ ) during the partial update process is larger than the filter coefficient W ( ⁇ ) during the full update process. Only when it is continuous beyond the bandwidth, it is recognized as a peak bandwidth.
- the bin setting unit 151 causes the speaker 113 to output a reference sound with a known frequency characteristic. Then, the bin setting unit 151 estimates the transfer characteristic C based on the frequency characteristic of the reference sound collected by the error microphone 112. The bin setting unit 151 derives the group delay characteristic of the transfer characteristic C and sets the frequency band in which the group delay amount is below the threshold D1 as the notch band F22 (see FIG. 4B). The bin setting unit 151 always sets the update parameter ⁇ to zero for the frequency bins 92 constituting the notch band F22.
- the bin setting unit 151 can grasp the peak band F21 and the notch band F22 based on the actual characteristic of the transfer characteristic C, the frequency bins 91 and 92 can be set based on the actual characteristic of the transfer characteristic C. An excellent silencing effect can be obtained.
- the signal processing device 12B preferably includes the bin setting unit 151 that sets the frequency bin 91 (second frequency bin) and the frequency bin 92 (third frequency bin).
- the bin setting unit 151 has a gain by the filter coefficient W when the update parameter ⁇ that cannot correct the filter coefficient W is set larger than a gain by the filter coefficient W when the update parameter ⁇ that can correct the filter coefficient W is set.
- the bin setting unit 151 sets the extracted frequency bin to the frequency bin 91 (second frequency bin).
- the bin setting unit 151 extracts frequency bins in which the group delay amount of the transfer characteristic C of the acoustic path from the speaker 113 to the error microphone 112 is lower than the threshold D1, from other than the frequency band F1 of the first noise, and this extraction
- the frequency bin thus set is set to the frequency bin 92 (third frequency bin).
- the signal processing device 12B can accurately grasp the peak band F21 and the notch band F22 by the bin setting unit 151, a more excellent silencing effect can be obtained.
- the computer constituting the signal processing device 12 or 12A or 12B includes a processor and an interface that operate according to a program as main hardware configurations.
- This type of processor includes a DSP (Digital Signal Processor), a CPU (Central Processing Unit), an MPU (Micro-Processing Unit), and the like. And if a processor can implement
- DSP Digital Signal Processor
- CPU Central Processing Unit
- MPU Micro-Processing Unit
- a computer-readable ROM Read Only Memory
- a form stored in advance in a recording medium such as an optical disk, or the like is supplied to the recording medium via a wide area communication network including the Internet.
- a wide area communication network including the Internet.
- the program is characterized by causing a computer to function as the signal processing device 12 or 12A or 12B.
- the range hood device 2 includes a hollow duct 21, a fan 22, a reference microphone 111, a speaker 113, an error microphone 112, and a signal processing device 12 (or 12A or 12B). To do.
- the hollow duct 21 corresponds to an air passage
- the reference microphone 111 corresponds to a first sound input device
- the speaker 113 corresponds to a sound output device
- the error microphone 112 corresponds to a second sound input device.
- the error microphone 112, the speaker 113, and the reference microphone 111 are arranged in this order from one end of the duct 21 to the other end.
- the fan 22 generates an air flow from one end of the duct 21 toward the other end.
- the reference microphone 111 is provided in the duct 21 and collects the first noise generated by the fan 22.
- the speaker 113 emits a cancel sound in the duct 21 that cancels the first noise when the cancel signal is input.
- the error microphone 112 collects a synthesized sound of the first noise and the cancel sound in the
- a program that causes a computer to function as the signal processing device 12 or 12A or 12B can also achieve the same effect as described above. That is, this program can reduce the load due to the calculation processing of the filter coefficient W ( ⁇ ). Further, this program can obtain an excellent silencing effect even when the peak band F21 and the notch band F22 exist in the transfer characteristic C from the speaker 113 to the error microphone 112.
- the range hood device 2 equipped with the signal processing device 12 or 12A or 12B can reduce the load due to the calculation processing of the filter coefficient W ( ⁇ ). Further, the range hood device 2 can obtain an excellent silencing effect even when the peak band F21 and the notch band F22 exist in the transfer characteristic C from the speaker 113 to the error microphone 112.
- the frequency bin selection method in the signal processing device 12 or 12A or 12B has the following characteristics as shown in the flowchart of FIG. First, among the frequency bins that do not correspond to the frequency band F1 of the first noise emitted from the fan 22 (noise source), the gain by the filter coefficient W when the update parameter ⁇ that cannot correct the filter coefficient W is set is the filter. A frequency bin larger than the gain by the filter coefficient W when the update parameter ⁇ capable of correcting the coefficient W is set is set as a frequency bin 91 (second frequency bin) (S10).
- the frequency bin 92 (the third bin) in which the group delay amount of the transfer characteristic C of the acoustic path from the speaker 113 to the error microphone 112 is less than the threshold D1.
- Frequency bin (S11). Note that the order of step S10 and step S11 may be reversed.
- the signal processing device 12 or 12A or 12B can accurately set the peak band F21 and the notch band F22, an excellent silencing effect can be obtained.
- devices other than the range hood device 2 may include the silencer 1 of each of the above-described embodiments.
Abstract
Description
図1は、本実施形態の消音装置1(能動騒音制御装置)の構成を示しており、レンジフード装置2が消音装置1を備えている。
本実施形態の消音装置1A(能動騒音制御装置)の構成を図9に示す。消音装置1Aは、実施形態1の消音装置1と同様の構成には同一の符号を付して、説明は省略する。
本実施形態の消音装置1B(能動騒音制御装置)の構成を図11に示す。消音装置1Bは、実施形態1の消音装置1と同様の構成には同一の符号を付して、説明は省略する。
2 レンジフード装置
11 音入出力装置
12、12A、12B 信号処理装置
21 ダクト(通気路)
22 ファン
111 参照マイクロホン(第1音入力器)
112 誤差マイクロホン(第2音入力器)
113 スピーカ(音出力器)
133 第1信号変換部
134 第2信号変換部
135 係数更新部
136 キャンセル信号生成部
136a 消音フィルタ
137、137A パラメータ設定部
141 データ取得部
151 ビン設定部
Claims (6)
- 騒音源から発せられた第1騒音が伝播する空間に設けられて前記第1騒音を集音する第1音入力器と、キャンセル信号が入力されて前記第1騒音を打ち消すキャンセル音を前記空間に発する音出力器と、前記空間において前記第1騒音と前記キャンセル音との合成音を集音する第2音入力器とを備える音入出力装置と組み合わせて用いられる信号処理装置であって、
所定の周波数帯域を分割した複数の周波数ビンのそれぞれにフィルタ係数が設定された消音フィルタを具備して、前記第1音入力器の出力に基づいて生成された騒音信号が入力されて前記キャンセル信号を出力するキャンセル信号生成部と、
前記第1音入力器の出力、前記第2音入力器の出力、および前記フィルタ係数を繰り返し算出する処理における前記フィルタ係数の補正量の大きさに関係する更新パラメータに基づいて、前記複数の周波数ビンのそれぞれの前記フィルタ係数を算出する係数更新部と、
前記複数の周波数ビンのそれぞれの前記更新パラメータを設定するパラメータ設定部とを備え、
前記パラメータ設定部は、
前記複数の周波数ビンのうち前記第1騒音の周波数帯域に対応する第1周波数ビン、および前記複数の周波数ビンのうち前記第1騒音とは異なる第2騒音の周波数帯域に対応する第2周波数ビンに対しては、前記フィルタ係数を補正できるように前記更新パラメータを設定し、
前記複数の周波数ビンのうち前記第1騒音および前記第2騒音のいずれの周波数帯域にも対応しない周波数ビンのうち、前記音出力器から前記第2音入力器に至る音響経路の伝達特性が落ち込むノッチ帯域の第3周波数ビンに対しては、前記フィルタ係数を補正しないように前記更新パラメータを設定する
信号処理装置。 - さらに、前記空間の温度データを取得するデータ取得部を備え、
前記パラメータ設定部は、前記空間の温度に応じて、前記第2周波数ビンおよび前記第3周波数ビンを選択する
請求項1記載の信号処理装置。 - さらに、前記第2周波数ビンおよび前記第3周波数ビンを設定するビン設定部を備え、
前記ビン設定部は、
前記フィルタ係数を補正できない前記更新パラメータが設定された場合の前記フィルタ係数によるゲインが、前記フィルタ係数を補正できる前記更新パラメータが設定された場合の前記フィルタ係数によるゲインより大きくなる周波数ビンを、前記第1騒音の周波数帯域以外から抽出して、この抽出した周波数ビンを前記第2周波数ビンに設定し、
前記音出力器から前記第2音入力器に至る音響経路の伝達特性の群遅延量が閾値を下回る周波数ビンを、前記第1騒音の周波数帯域以外から抽出して、この抽出した周波数ビンを前記第3周波数ビンに設定する
請求項1または2記載の信号処理装置。 - コンピュータを、請求項1乃至3いずれか記載の信号処理装置として機能させることを特徴とするプログラム。
- 中空状の通気路と、前記通気路の一端から他端に向かう気流を発生させるファンと、前記通気路内に設けられて前記ファンが発する第1騒音を集音する第1音入力器と、キャンセル信号が入力されて前記第1騒音を打ち消すキャンセル音を前記通気路内に発する音出力器と、前記通気路内において前記第1騒音と前記キャンセル音との合成音を集音する第2音入力器と、請求項1乃至3いずれか記載の信号処理装置とを備え、前記通気路の前記一端から前記他端に向かって、前記第2音入力器、前記音出力器、前記第1音入力器の順に配置されるレンジフード装置。
- 請求項1乃至3いずれか記載の信号処理装置における周波数ビンの選択方法であって、
騒音源から発せられた第1騒音の周波数帯域に対応しない周波数ビンのうち、前記フィルタ係数を補正できない前記更新パラメータが設定された場合の前記フィルタ係数によるゲインが、前記フィルタ係数を補正できる前記更新パラメータが設定された場合の前記フィルタ係数によるゲインより大きくなる周波数ビンを、前記第2周波数ビンとし、
前記第1騒音の周波数帯域に対応しない周波数ビンのうち、前記音出力器から前記第2音入力器に至る音響経路の伝達特性の群遅延量が閾値を下回る周波数ビンを、前記第3周波数ビンに設定する
信号処理装置における周波数ビンの選択方法。
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2016556195A JP6429174B2 (ja) | 2014-10-28 | 2015-10-15 | 信号処理装置、プログラム、レンジフード装置、および信号処理装置における周波数ビンの選択方法 |
US15/503,791 US10240812B2 (en) | 2014-10-28 | 2015-10-15 | Signal processing device, program, range hood device, and selection method for frequency bins in signal processing device |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2014219587 | 2014-10-28 | ||
JP2014-219587 | 2014-10-28 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2016067540A1 true WO2016067540A1 (ja) | 2016-05-06 |
Family
ID=55856909
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2015/005208 WO2016067540A1 (ja) | 2014-10-28 | 2015-10-15 | 信号処理装置、プログラム、レンジフード装置、および信号処理装置における周波数ビンの選択方法 |
Country Status (3)
Country | Link |
---|---|
US (1) | US10240812B2 (ja) |
JP (1) | JP6429174B2 (ja) |
WO (1) | WO2016067540A1 (ja) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106439961A (zh) * | 2016-08-31 | 2017-02-22 | 杭州老板电器股份有限公司 | 侧吸式吸油烟机降噪装置 |
Families Citing this family (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10037755B2 (en) * | 2016-11-25 | 2018-07-31 | Signal Processing, Inc. | Method and system for active noise reduction |
DE102017200822A1 (de) * | 2017-01-19 | 2018-07-19 | Bayerische Motoren Werke Aktiengesellschaft | Belüftungseinrichtung für einen Innenraum eines Kraftwagens und Verfahren zum Betrieb einer solchen Belüftungseinrichtung |
US11463212B2 (en) * | 2017-12-29 | 2022-10-04 | Apple Inc. | Methods of frequency domain intra-orthogonal frequency-division multiplexing (OFDM) symbol multi RX-beam measurement and dynamic RX beam sweeping |
CN109282479B (zh) * | 2018-09-17 | 2021-02-23 | 青岛海信日立空调系统有限公司 | 空调降噪装置及降噪方法 |
US11217222B2 (en) * | 2019-07-19 | 2022-01-04 | Cirrus Logic, Inc. | Input signal-based frequency domain adaptive filter stability control |
US10984778B2 (en) * | 2019-07-19 | 2021-04-20 | Cirrus Logic, Inc. | Frequency domain adaptation with dynamic step size adjustment based on analysis of statistic of adaptive filter coefficient movement |
US10789933B1 (en) * | 2019-07-19 | 2020-09-29 | Cirrus Logic, Inc. | Frequency domain coefficient-based dynamic adaptation control of adaptive filter |
CN114448500A (zh) * | 2020-11-03 | 2022-05-06 | 富士通株式会社 | 相频响应测量方法和装置 |
US11496831B2 (en) | 2021-04-06 | 2022-11-08 | Gulfstream Aerospace Corporation | Active noise cancellation of equipment fan noise on aircraft |
TWI803300B (zh) * | 2021-05-25 | 2023-05-21 | 英屬開曼群島商意騰科技股份有限公司 | 具有降噪功能之風扇控制系統及方法 |
TWI811768B (zh) * | 2021-08-19 | 2023-08-11 | 宏碁股份有限公司 | 具散熱和前饋式主動噪音控制功能之電子系統 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3617079B2 (ja) * | 1994-08-29 | 2005-02-02 | 日産自動車株式会社 | 能動型騒音制御装置及び能動型振動制御装置 |
JP5503023B2 (ja) * | 2011-01-06 | 2014-05-28 | パイオニア株式会社 | 能動型振動騒音制御装置、能動型振動騒音制御方法及び能動型振動騒音制御プログラム |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3250224B2 (ja) | 1991-03-12 | 2002-01-28 | 三菱電機株式会社 | 能動騒音低減装置 |
JP3549120B2 (ja) | 1994-01-26 | 2004-08-04 | 本田技研工業株式会社 | 車両用能動振動制御装置 |
JP4513810B2 (ja) | 2005-07-21 | 2010-07-28 | パナソニック株式会社 | 能動騒音低減装置 |
JP2012168283A (ja) | 2011-02-10 | 2012-09-06 | Tokai Rubber Ind Ltd | 能動型振動騒音抑制装置 |
JP5832839B2 (ja) | 2011-09-27 | 2015-12-16 | パイオニア株式会社 | 能動型騒音制御装置及び能動型騒音制御方法 |
-
2015
- 2015-10-15 JP JP2016556195A patent/JP6429174B2/ja active Active
- 2015-10-15 US US15/503,791 patent/US10240812B2/en active Active
- 2015-10-15 WO PCT/JP2015/005208 patent/WO2016067540A1/ja active Application Filing
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3617079B2 (ja) * | 1994-08-29 | 2005-02-02 | 日産自動車株式会社 | 能動型騒音制御装置及び能動型振動制御装置 |
JP5503023B2 (ja) * | 2011-01-06 | 2014-05-28 | パイオニア株式会社 | 能動型振動騒音制御装置、能動型振動騒音制御方法及び能動型振動騒音制御プログラム |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106439961A (zh) * | 2016-08-31 | 2017-02-22 | 杭州老板电器股份有限公司 | 侧吸式吸油烟机降噪装置 |
CN106439961B (zh) * | 2016-08-31 | 2018-06-12 | 杭州老板电器股份有限公司 | 侧吸式吸油烟机降噪装置 |
Also Published As
Publication number | Publication date |
---|---|
JP6429174B2 (ja) | 2018-11-28 |
US20170276398A1 (en) | 2017-09-28 |
US10240812B2 (en) | 2019-03-26 |
JPWO2016067540A1 (ja) | 2017-08-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6429174B2 (ja) | 信号処理装置、プログラム、レンジフード装置、および信号処理装置における周波数ビンの選択方法 | |
JP6384784B2 (ja) | 信号処理装置、プログラム、レンジフード装置 | |
JP6343970B2 (ja) | 信号処理装置、プログラム、レンジフード装置 | |
WO2016178309A1 (ja) | 信号処理装置、信号処理方法、プログラム、レンジフード装置 | |
JP4790843B2 (ja) | 能動消音装置および能動消音方法 | |
JP4742226B2 (ja) | 能動消音制御装置及び方法 | |
JP5707663B2 (ja) | 能動消音装置 | |
JP2013109352A (ja) | 調整可能なアクティブ雑音制御 | |
JP6179062B2 (ja) | 能動騒音制御装置、プログラム、レンジフード装置 | |
JP2012123135A (ja) | 能動騒音低減装置 | |
WO2019044564A1 (ja) | 信号処理装置、消音システム、信号処理方法、及びプログラム | |
JP6214884B2 (ja) | 能動消音装置および能動消音方法 | |
JP6614534B2 (ja) | 信号処理装置、プログラム、およびレンジフード装置 | |
JP6116300B2 (ja) | 能動型消音システム | |
JP2014174348A (ja) | 消音装置および消音方法 | |
JP2002328681A (ja) | 能動的騒音制御装置 | |
JP2012141532A (ja) | 能動騒音低減装置 | |
US20240098408A1 (en) | Noise reduction system and noise reduction method | |
JP4350919B2 (ja) | 能動型雑音除去装置 | |
JP4438632B2 (ja) | ハウリングキャンセラ | |
JPH0635482A (ja) | アクティブ消音方法及び消音装置 | |
JP2001042875A (ja) | 適応型能動消音装置 | |
JP2011043636A (ja) | 能動型消音システム | |
JP2002333887A (ja) | 伝達関数同定装置及び能動型雑音除去装置 | |
JPH0561490A (ja) | アクテイブ消音装置 |
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: 15853798 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2016556195 Country of ref document: JP Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 15503791 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 15853798 Country of ref document: EP Kind code of ref document: A1 |