Nothing Special   »   [go: up one dir, main page]

WO2019157698A1 - Detection circuit and method - Google Patents

Detection circuit and method Download PDF

Info

Publication number
WO2019157698A1
WO2019157698A1 PCT/CN2018/076812 CN2018076812W WO2019157698A1 WO 2019157698 A1 WO2019157698 A1 WO 2019157698A1 CN 2018076812 W CN2018076812 W CN 2018076812W WO 2019157698 A1 WO2019157698 A1 WO 2019157698A1
Authority
WO
WIPO (PCT)
Prior art keywords
signal
audio playback
sound signal
impedance
transmission
Prior art date
Application number
PCT/CN2018/076812
Other languages
French (fr)
Chinese (zh)
Inventor
王欣民
Original Assignee
深圳市汇顶科技股份有限公司
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 深圳市汇顶科技股份有限公司 filed Critical 深圳市汇顶科技股份有限公司
Priority to PCT/CN2018/076812 priority Critical patent/WO2019157698A1/en
Priority to CN201880000300.6A priority patent/CN110383854B/en
Publication of WO2019157698A1 publication Critical patent/WO2019157698A1/en

Links

Images

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00Circuits for transducers, loudspeakers or microphones

Definitions

  • the present invention relates to an audio playback driving unit, and more particularly to a detection circuit for detecting whether an audio playback driving unit is located in a predetermined resonance environment and related methods.
  • Existing audio playback systems use an audio playback driver/transducer (such as a playback drive unit of a speaker or earphone) to play a sound signal.
  • an audio playback driver/transducer such as a playback drive unit of a speaker or earphone
  • a user wears a Bluetooth headset to listen to music played on the phone.
  • the Bluetooth headset continues to play music, which not only increases unnecessary power consumption, but also shortens the life of the battery.
  • an innovative audio playback detection mechanism that can detect the usage context of an audio playback system/audio playback driver unit to adjust its operational state (e.g., selectively enter a power save mode) to implement an intelligent audio playback system.
  • One of the objects of the present invention is to disclose a detection circuit for detecting whether an audio playback drive unit is located in a predetermined resonance environment and related methods to solve the above problems.
  • Another object of the present invention is to disclose a detection circuit and related method that can provide suitable audio playback quality according to the resonant environment in which the audio playback drive unit is located, to meet the listening needs of the user.
  • An embodiment of the invention discloses a detection circuit.
  • the detection circuit includes a transmission circuit and a processing circuit.
  • the transmission circuit is configured to receive a first sound signal and is coupled to the audio playback driving unit, wherein the transmission circuit generates a second sound signal according to the first sound signal to the audio playback driving unit, and at least according to the The first sound signal and the second sound signal generate a characteristic signal.
  • the processing circuit is coupled to the transmission circuit to receive the characteristic signal, and the processing circuit detects whether the audio playback driving unit is located in a predetermined resonance environment according to at least the first sound signal and the characteristic signal.
  • An embodiment of the invention discloses a detection method.
  • the method includes the steps of: feeding a first sound signal to a first transmission path coupled to an audio playback driving unit to generate a second sound signal to the audio playback driving unit; at least according to the first sound signal Generating, by the second sound signal, a feature signal on a second transmission path coupled to the audio playback driving unit, wherein the second transmission path is different from the first transmission path; and at least according to the first sound
  • the signal and the characteristic signal detect whether the audio playback drive unit is in a predetermined resonance environment.
  • FIG. 1 is a functional block diagram of an audio playback system in accordance with an embodiment of the present invention.
  • FIG. 2 is a schematic diagram of an embodiment of the audio playback system shown in FIG. 1.
  • FIG. 3 is a flow chart of a method for detecting whether an audio playback drive unit is located in a predetermined resonance environment according to an embodiment of the present invention.
  • the audio playback detection mechanism disclosed by the present invention can detect the signal response of the audio playback driving unit on the sound input side, and use the audio playback driving unit as a sensing device of the surrounding environment to detect the resonance of the audio playback driving unit.
  • Environment or geometry/shape of the cavity. Further explanation is as follows.
  • the audio playback system 100 includes, but is not limited to, an audio playback driver unit (or audio playback transducer) 102, a detection circuit 104, and a signal generation circuit 106, wherein at least a portion of the audio playback system 100 It can be implemented by an electronic device having an audio playback function.
  • the audio playback driving unit 102, the detecting circuit 104, and the signal generating circuit 106 may be at least a part of an electronic device (such as a mobile phone, a palmtop computer, or a notebook computer), wherein the audio playback driving unit 102 is built in the electronic device.
  • Playing a driving unit such as a playback drive unit of a speaker or a headphone
  • the detecting circuit 104 and the signal generating circuit 106 may be at least a part of an electronic device such as a mobile phone, a palmtop computer or a notebook computer
  • the unit 102 may be a playback drive unit (such as a playback drive unit of a speaker or an earphone) externally connected to the electronic device; for example, the signal generation circuit 106 may be at least a part of an electronic device such as a mobile phone, a palmtop computer or a notebook computer.
  • the audio playback driving unit 102 and the detecting circuit 104 can be located in an audio playing device (such as a speaker or an earphone) external to the electronic device.
  • the resonance environment in which the audio playback driving unit 102 is located may affect its signal response, and the detecting circuit 104 may detect the resonance environment in which the audio playback driving unit 102 is located according to the signal response of the audio playback driving unit 102 (for example, whether it is located or not) a predetermined resonance environment).
  • the audio playback driving unit 102 when the audio playback driving unit 102 is implemented by the playback driving unit of the earphone, when the audio playback driving unit 102 is in the first resonance environment (for example, the user wears the earphone), the audio playback driver The resonant cavity of unit 102 has a first geometry/shape (eg, the geometric resonant space inherent to audio playback drive unit 102 in conjunction with the ear canal geometry of the user), and the input impedance of audio playback drive unit 102 can have a first frequency response characteristic
  • the resonant cavity of the audio playback drive unit 102 has a second geometry/shape (eg, inherent to the audio playback drive unit 102)
  • the geometric resonance space) the input impedance of the audio playback drive unit 102 can have a second frequency response characteristic. Therefore, the detecting circuit 104 can detect the resonance environment (or use context) in which the audio playback driving unit 102
  • the detecting circuit 104 outputs the sound signal AS2 to the audio playback driving unit 102 based on the sound signal AS1 supplied from the signal generating circuit 106, thereby detecting the input impedance/frequency response of the audio playback driving unit 102.
  • the detection circuit 104 includes, but is not limited to, a transmission circuit 110 and a processing circuit 120.
  • the transmission circuit 110 is coupled between the audio playback driving unit 102 and the signal generating circuit 106 for receiving the sound signal AS1, and transmits the sound signal AS1 to the audio playback driving unit 102, thereby generating the sound signal AS2 and obtaining the characteristic signal CHS.
  • the transmission circuit 110 can generate the characteristic signal CHS according to the sound signal AS1 and the sound signal AS2.
  • the transmission circuit 110 includes an input port P1, an output port P2, and an output port P3.
  • the input port P1 is configured to receive the sound signal AS1, the output port P2 is coupled to the audio playback drive unit 102, and the output port P3 is coupled to the processing circuit 120.
  • the transmission circuit 110 can generate the sound signal AS2 according to the sound signal AS1, output to the audio playback driving unit 102 through the output port P2, and generate the characteristic signal CHS based on at least the sound signal AS1 and the sound signal AS2, and output to the processing circuit 120 through the output port P3.
  • the processing circuit 120 is coupled to the transmission circuit 110 and the signal generating circuit 106 for receiving the characteristic signal CHS, and detecting whether the audio playback driving unit 102 is located in a predetermined resonance environment according to at least the sound signal AS1 and the characteristic signal CHS (for example, detecting whether the user is The audio playback device including the audio playback drive unit 102 is worn.
  • the processing circuit 120 can detect the input impedance or frequency response of the audio playback driving unit 102 according to the signal strength information, phase information, and/or gain information of the characteristic signal CHS and the sound signal AS1. Thereby detecting whether the audio playback drive unit 102 is in a predetermined resonance environment.
  • the processing circuit 120 determines that the audio playback driving unit 102 is located in the predetermined resonance environment; when the signal strength of the characteristic signal CHS is not within the intensity characteristic range with respect to the signal strength of the sound signal AS1, or the phase of the characteristic signal CHS relative to the sound signal AS1 When the change is not within the phase feature range, the processing circuit 120 can determine that the audio playback drive unit 102 is not located in the predetermined resonance environment.
  • the invention is not limited thereto.
  • the processing circuit 120 can receive the sound signal AS1 to directly detect the sound signal AS1 and the characteristic signal CHS, and can also receive the sound signal AS0 to indirectly detect the sound signal AS1 and the characteristic signal CHS, wherein the sound signal AS0 is the sound signal AS1
  • the signal generation circuit 106 outputs the previous pending version. That is, the signal generating circuit 106 may perform preprocessing (such as a digital-to-analog conversion operation) on the sound signal AS0 to generate the sound signal AS1. Similarly, the processing circuit 120 may directly detect the feature signal CHS, or may perform pre-processing (such as analog-to-digital conversion operation) on the feature signal CHS, and then detect the processed feature signal CHS.
  • transmission circuit 110 can perform impedance matching for a predetermined input impedance, which can be an input impedance of audio playback drive unit 102 when in the predetermined resonant environment.
  • the processing circuit 120 can detect a signal response with respect to the input impedance of the audio playback driving unit 102 based on the sound signal AS1 and the characteristic signal CHS.
  • the audio playback driving unit 102 when it is detected that the signal component from the sound signal AS1 among the characteristic signals CHS obtained by the transmission circuit 110 is less than a predetermined ratio, this means that the audio playback driving unit 102 currently has an input impedance equal to (or substantially equal to) the said The input impedance is predetermined, and the processing circuit 120 can determine that the audio playback drive unit 102 is in the predetermined resonant environment.
  • FIG. 2 is a schematic diagram of an embodiment of the audio playback system 100 shown in FIG. 1.
  • the audio playback system 200 includes, but is not limited to, an audio playback driver unit 202, a detection circuit 204, and a signal generation circuit 206, wherein the audio playback driver unit 102, the detection circuit 104, and the signal generation circuit 106 shown in FIG.
  • the playback drive unit 202, the detection circuit 204, and the signal generation circuit 206 are implemented.
  • the detection circuit 204 includes a transmission circuit 210 and a processing circuit 220.
  • the transmission circuit 110 and the processing circuit 120 shown in FIG. 1 can be implemented by the transmission circuit 210 and the processing circuit 220, respectively.
  • signal generation circuit 206 includes, but is not limited to, digital signal processing circuit 207, digital to analog converter 208 (labeled “DAC”), and output unit 209 (labeled “BF1"), where output unit 209 It can be implemented by a power amplifier.
  • the digital signal processing circuit 207 generates a sound signal TD (digital sound signal) to the digital to analog converter 208. After the processing by the digital-to-analog converter 208 and the output unit 209, the sound signal TD can be converted into a sound signal TA (analog sound signal).
  • the sound signal TA forms a sound signal SL to the audio playback driving unit 202 after passing through the transmission circuit 210, and the sound signal SL changes according to a change in the input impedance of the audio playback driving unit 202.
  • the transmission circuit 210 also generates a characteristic signal RA to the processing circuit 220 based on the sound signal TA and the sound signal SL.
  • the transmission circuit 210 can detect the signal response (or input impedance variation) of the audio playback driving unit 202 by means of circuit matching.
  • the transmission circuit 210 may be implemented by a hybrid matching network (such as a hybrid impedance matching circuit), and may include an input port IP and an output port OP1.
  • the output port OP2 and the plurality of transmission paths 212-216 wherein the transmission path 212 is coupled between the input port IP and the output port OP1, the transmission path 214 is coupled between the output port OP1 and the output port OP2, and the transmission path 216 It is coupled between the input port IP and the output port OP2.
  • Processing circuit 220 includes, but is not limited to, input unit 222 (labeled “BF2”), analog to digital converter 224 (labeled “ADC”), and impedance detector 226, where input unit 222 can be implemented by a buffer.
  • the analog-to-digital converter 224 can convert the characteristic signal RA (analog signal) buffered by the input unit 222 to generate a characteristic signal RD (digital signal), and the impedance detector 226 can be based on the digital version corresponding to the sound signal TA (sound signal TD)
  • the digital version (feature signal RD) corresponding to the feature signal RA detects whether the audio playback drive unit 202 is in a predetermined resonance environment.
  • the output impedance of the output unit 209 (or the output impedance of the signal generating circuit 206) is relative to the input impedance of the audio playback driving unit 202 (the impedance of the electrical load of the signal generating circuit 206). It is said to be small, therefore, different signal responses (such as response characteristics of the characteristic signal RA) are generated according to changes in the resonant environment (resonator geometry/shape) of the audio playback drive unit 202, and the impedance detector 226 can detect The input impedance of the audio playback drive unit 202 changes, thereby determining the resonant environment in which the audio playback drive unit 202 is located.
  • the transmission impedance between the input port IP and the output port OP1 can be matched to a predetermined input impedance Z_Load, wherein the predetermined input impedance Z_Load is the audio playback driving unit 202 located at the The input impedance is seen from the output port OP1 in a predetermined resonance environment (corresponding to the resonant cavity RS1), and the impedance Z_I1 and the impedance Z_I2 may both be equal to, but not limited to, one-half of the predetermined input impedance Z_Load.
  • the transmission impedance between the output port OP1 and the output port OP2 (the transmission impedance of the transmission path 214) and the input port IP and The transmission impedance between the output ports OP2 (the transmission impedance of the transmission path 216) can greatly reduce the signal component from the sound signal TA among the characteristic signals RA.
  • the transmission impedance between the output port OP1 and the output port OP2 may be, but is not limited to, one-half of the transmission impedance between the input port IP and the output port OP2 to be passed through the transmission path 214 to the output port OP2.
  • the signal (corresponding to the sound signal SL) can cancel (or substantially cancel) the signal (corresponding to the sound signal TA) transmitted to the output port OP2 through the transmission path 216, wherein the impedance Z_R1 can be equal to the impedance Z_R2, and the impedance Z_X1 can be equal to the impedance Z_X2 And the impedance Z_R1 and the impedance Z_R2 can both be equal to one-half of the impedance Z_X1 (impedance Z_X2).
  • the characteristic signal RA is less affected by the sound signal TA, and the signal strength of the sound signal TA is attenuated a lot (or attenuated to zero). That is to say, in the case of some circuit matching, the presence (or variation) of the sound signal TA equivalently does not (or hardly affect) the signal generated by the output port OP2.
  • the characteristic signal RA generated by OP2 can have a high sensitivity to changes in the circuit matching situation.
  • the characteristic signal RA can be very sensitive to changes in the input impedance of the audio playback drive unit 202 (the situation in which the circuit matching changes).
  • the impedance detector 226 detects that the signal strength of the characteristic signal RD with respect to the sound signal TD is within a range of intensity characteristics (eg, the signal strength of the characteristic signal RD is attenuated by more than 20 decibels compared to the sound signal TD, or The attenuation is between 20 decibels and 40 decibels, which means that the transmission circuit 210 has greatly reduced the signal component from the sound signal TA among the characteristic signals RA by impedance matching, and the impedance detector 226 (or the processing circuit 220) can detect
  • the outgoing audio playback drive unit 202 is located in the predetermined resonant environment.
  • the impedance detector 226 detects that the signal strength of the feature signal RD with respect to the sound signal TD is not within the intensity characteristic range, the impedance detector 226 (or the processing circuit 220) can detect the audio playback driving unit 202. Not located in the predetermined resonant environment.
  • the impedance detector 226 detects that the signal strength of the feature signal RD relative to the sound signal TD is not within the intensity feature range but is within another intensity feature range, the impedance detector 226 (or processing circuit) 220) It can be detected that the audio playback driving unit 202 is located in another predetermined resonance environment (corresponding to another resonant cavity RS2), wherein the predetermined resonance environment corresponding to the resonant cavity RS1 can be, but is not limited to, the user wears the audio playback driver.
  • the predetermined resonance environment corresponding to the resonant cavity RS2 may be, but is not limited to, the user removing the earphone including the audio playback driving unit 202.
  • impedance detector 226 when the impedance detector 226 detects that the phase change of the feature signal RD relative to the sound signal TD is within a phase feature range (eg, the phase change of the feature signal RD exceeds the sound signal TD) a predetermined angle, or within a predetermined range of variation, which means that the transmission circuit 210 has substantially reduced the signal component from the sound signal TA among the characteristic signals RA by impedance matching, or means that the cavity of the audio playback driving unit 202 At a particular resonant frequency or at multiple resonant frequencies (overtones) at the same time, impedance detector 226 (or processing circuit 220) can detect that audio playback drive unit 202 is in the predetermined resonant environment.
  • a phase feature range eg, the phase change of the feature signal RD exceeds the sound signal TD
  • impedance detector 226 can detect that audio playback drive unit 202 is in the predetermined resonant environment.
  • the impedance detector 226 When the impedance detector 226 detects that the phase change of the characteristic signal RD with respect to the sound signal TD is not within the phase characteristic range, the impedance detector 226 (or the processing circuit 220) can detect that the audio playback driving unit 202 is not located.
  • the predetermined resonance environment When the impedance detector 226 detects that the phase change of the characteristic signal RD with respect to the sound signal TD is not within the phase characteristic range, the impedance detector 226 (or the processing circuit 220) can detect that the audio playback driving unit 202 is not located.
  • the predetermined resonance environment When the impedance detector 226 detects that the phase change of the characteristic signal RD with respect to the sound signal TD is not within the phase characteristic range, the impedance detector 226 (or the processing circuit 220) can detect that the audio playback driving unit 202 is not located. The predetermined resonance environment.
  • the impedance detector 226 when the impedance detector 226 detects that the signal strength of the characteristic signal RD relative to the sound signal TD is within a range of intensity characteristics, and the phase change of the characteristic signal RD relative to the sound signal TD is between When the phase characteristic range is within (for example, the signal strength of the characteristic signal RD is attenuated by more than 20 decibels compared to the sound signal TD, and the phase change of the characteristic signal RD is within a predetermined variation range), which means that the transmission circuit 210 passes Impedance matching has substantially reduced the signal component from the sound signal TA among the characteristic signals RA, or means that the resonant cavity of the audio playback drive unit 202 may be at a particular resonant frequency or at multiple resonant frequencies simultaneously, the impedance detector 226 (or processing) The circuit 220) can detect that the audio playback drive unit 202 is in the predetermined resonant environment.
  • the impedance detector 226 detects that the signal strength of the characteristic signal RD with respect to the sound signal TD is not within the intensity characteristic range, and the phase change of the characteristic signal RD with respect to the sound signal TD is not within the phase characteristic range
  • the impedance detector 226 (or processing circuit 220) can then detect that the audio playback drive unit 202 is not located in the predetermined resonant environment.
  • the characteristic signal RA generated by the transmission circuit 210 can reflect the input impedance change of the audio playback driving unit 202, and the impedance detector 226 can obtain the obtained signal.
  • Features such as signal strength and/or phase changes detect the resonant environment in which the audio playback drive unit 202 is currently located.
  • the transmission circuit 210 may perform impedance matching for a predetermined frequency range Z_Load over a specific frequency range, wherein the specific frequency range may be within or outside the range of frequencies perceived by the human ear.
  • the audio playback driving unit 202 is configured to play a sound signal whose frequency range is within an audible sound frequency range (ie, an ear-perceivable audio signal, such as a symphony generated by the signal generating circuit 206).
  • the processing circuit 220 can simultaneously detect the resonance environment in which the audio playback driving unit 202 is located according to the frequency response of the sound signal (generated by the signal generation circuit 206), or according to the signal generation circuit 206.
  • the frequency response of another generated sound signal e.g., ultrasonic signal
  • the specific frequency range may include at least one of a frequency range of the ultrasonic waves and a frequency range of the audible sound waves.
  • transmission circuit 210 may receive noise signal SN from audio playback drive unit 202 via output port OP1, which may be a sound signal of a surrounding environment (such as a heartbeat or speech sound of a human body). That is to say, the characteristic signal RA may contain a signal component from the noise signal SN. Since the detecting circuit 204 can sensitively detect the input impedance change (or frequency response) generated by the audio playback driving unit 202 in response to the change of the resonance environment, the characteristic signal RA generated by the transmission circuit 210 can still reflect the audio playback driving unit.
  • the input impedance variation of 202 (eg, the signal strength of the characteristic signal RD is substantially attenuated relative to the signal strength of the sound signal TD) such that the impedance detector 226 can be based on the characteristic signal RA and the sound signal TA (or the characteristic signal RD and the characteristic signal TD)
  • the resonance environment in which the audio playback drive unit 202 is currently located is detected, and is not susceptible to interference by the noise signal SN.
  • the processing circuit 220 can detect an impedance change caused by the change in the resonant environment of the audio playback drive unit 202.
  • the impedance detector 226 can directly perform a numerical calculation on the sound signal TA/TD and the characteristic signal RA/RD to determine the input impedance change of the audio playback driving unit 202.
  • the impedance detector 226 can directly perform a numerical calculation on the sound signal TA/TD and the sound signal SL to determine the input impedance of the audio playback driving unit 202. Variety.
  • processing circuit 220 may also adjust the transmission impedance of transmission path 214 (such as impedance Z_R1 and/or impedance Z_R2) to the transmission impedance of transmission path 216 (such as impedance Z_X1 and/or impedance Z_X2).
  • the ratio between the two is based on the ratio between the transmission impedance of the transmission path 214 and the transmission impedance of the transmission path 216, the sound signal TA and the characteristic signal RA to detect whether the audio playback driving unit 202 is located in the predetermined resonance environment.
  • the impedance Z_X1 and the impedance Z_X2 may each be implemented by an impedance array, wherein the impedance detector 226 may generate a control signal CS to the impedance Z_X1 and the impedance Z_X2 to control the impedance Z_X1 and the impedance Z_X2.
  • the impedance value is such that the signal strength of the characteristic signal RA relative to the sound signal TA (or the signal strength of the characteristic signal RD relative to the sound signal TD) is within a range of intensity characteristics and/or the phase of the characteristic signal RA relative to the sound signal TA The change (or the phase change of the characteristic signal RD with respect to the sound signal TD) is within a range of phase characteristics.
  • the impedance detector 226 may be based on a corresponding impedance ratio (such as a ratio between the impedance Z_X2 and the impedance Z_R1, and/or a ratio between the impedance Z_X1 and the impedance Z_R2), It is detected whether the audio playback drive unit 202 is located in the predetermined resonance environment.
  • a corresponding impedance ratio such as a ratio between the impedance Z_X2 and the impedance Z_R1, and/or a ratio between the impedance Z_X1 and the impedance Z_R2
  • the transmission circuit 210 can also be implemented by other circuit configurations.
  • the transmission circuit 210 may employ a transformer for circuit matching, and in a case of current subtraction, in a case where the audio playback driving unit 202 is located in the predetermined resonance environment, a signal from the sound signal TA among the characteristic signals RA is made. The composition has been greatly reduced.
  • FIG. 3 is a flowchart of a method for detecting whether an audio playback driving unit is located in a predetermined resonance environment. If the results obtained are substantially the same, the steps do not have to be performed in the order shown in FIG. For example, some steps can be placed in it.
  • the method shown in FIG. 3 will be described below in conjunction with the audio playback system 200 shown in FIG. 2. However, it is also feasible to apply the method shown in FIG. 3 to the audio playback system 100 shown in FIG. 1.
  • the method can be summarized as follows.
  • Step 310 Start.
  • the sound signal TD is generated by the digital signal processing circuit 207, and the sound signal TD is converted into the sound signal TA by the digital-to-analog converter 208 and the output unit 209.
  • Step 320 Feed the first sound signal to the first transmission path coupled to the audio playback driving unit to generate a second sound signal to the audio playback driving unit.
  • the sound signal TA is fed to the transmission path 212 coupled to the audio playback driving unit 202 to generate the sound signal SL to the audio playback driving unit 202.
  • Step 330 Generate a feature signal according to the second transmission path coupled to the audio playback driving unit, according to the first sound signal and the second sound signal, where the second transmission path is different from the first A transmission path.
  • the transmission circuit 210 generates a characteristic signal RA based at least on the transmission path 214 to which the audio signal SL is coupled to the audio playback drive unit 202, wherein the transmission path 214 is different from the transmission path 212.
  • Step 340 Detect whether the audio playback driving unit is located in the predetermined resonance environment according to at least the first sound signal and the characteristic signal.
  • the processing circuit 220 detects whether the audio playback drive unit 202 is located in the predetermined resonance environment based at least on the sound signal TA and the feature signal RA.
  • the transmission circuit 210 can couple the sound signal TA to the transmission path 214 through the transmission path 216 to generate the characteristic signal RA at the output port OP2 according to the sound signal TA and the sound signal SL.
  • the feature signal RA can reflect the circuit matching situation between the transmission circuit 210 and the audio playback drive unit 202.
  • transmission path 212, transmission path 214, and transmission path 216 are used to impedance match a predetermined input impedance, and the predetermined input impedance is when audio playback drive unit 202 is in the predetermined resonant environment.
  • Input impedance (such as a predetermined input impedance Z_Load).
  • step 340 when the signal strength of the feature signal RA relative to the sound signal TA is within a range of intensity characteristics (eg, the impedance detector 226 detects that the characteristic signal RD has a large amount of attenuation with respect to the signal strength of the sound signal TD), And/or when the phase change of the characteristic signal RA relative to the sound signal TA is within a phase characteristic range, the impedance detector 226 may determine that the audio playback driving unit 202 is located in the predetermined resonance environment; when the characteristic signal RA is relative to the sound signal TA When the signal strength is not within the range of the intensity characteristics, and/or the phase change of the characteristic signal RA relative to the sound signal TA is not within the phase feature range, the impedance detector 226 may determine that the audio playback driving unit 202 is not Located in the predetermined resonant environment.
  • a range of intensity characteristics eg, the impedance detector 226 detects that the characteristic signal RD has a large amount of attenuation with respect to the signal
  • the detection circuit and related detection method disclosed by the present invention can detect the resonance environment of the audio playback driving unit by detecting the signal response of the audio playback driving unit (such as the change of the input impedance). Or determine the resonant cavity geometry/shape of the audio playback drive unit).
  • the audio detection mechanism disclosed by the present invention can have a variety of applications.
  • the audio detection mechanism disclosed in the present invention can be used for wear detection to detect whether a user wears an audio playback device having the audio playback driving unit, and adjusts the user when the user does not wear the audio playback device.
  • the operating state of the audio playback drive unit (for example, entering the power saving mode) implements an intelligent audio playback system.
  • the disclosed audio detection mechanism can detect a user's wearing state, such as wearing it tightly or gently, to adjust the sound signal to be played (eg, adjusting the amplitude of the sound signal).
  • the audio detection mechanism disclosed by the present invention can adjust the sound signal to be played (for example, adjusting the signal characteristics of the high frequency and/or low frequency bands) to improve the audio playback quality.
  • the disclosed audio detection mechanism can be used to identify structural features of the human ear canal by detecting the resonant cavity geometry/shape in which the audio playback drive unit is located.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Circuit For Audible Band Transducer (AREA)

Abstract

A detection circuit (104) and a detection method. The detection circuit (104) comprises a transmission circuit (110) and a processing circuit (120). The transmission circuit (110) is configured to receive a first sound signal and is coupled to an audio playback driver (102). The transmission circuit (110) generates, according to the first sound signal, a second sound signal and sends the signal to the audio playback driving unit (102), and generates a characteristic signal (CHS) according to at least the first sound signal and the second sound signal. The processing circuit (120) is coupled to the transmission circuit (110) to receive the characteristic signal (CHS), and the processing circuit (120) detects, according to at least the first sound signal and the characteristic signal (CHS), whether the audio playback driver (102) is located in a predetermined resonance environment. The detection circuit (104) can detect a usage context of the audio playback driver (102) to adjust the operating status of the audio playback driver (102), so as to implement an intelligent audio playback system.

Description

一种侦测电路和方法Detection circuit and method 技术领域Technical field
本发明涉及音频播放驱动单元,尤其涉及一种用于侦测音频播放驱动单元是否位于预定共振环境的侦测电路及其相关的方法。The present invention relates to an audio playback driving unit, and more particularly to a detection circuit for detecting whether an audio playback driving unit is located in a predetermined resonance environment and related methods.
背景技术Background technique
现有的音频播放系统会利用音频播放驱动单元/换能器(acoustic playback driver/transducer)(诸如喇叭或耳机的播放驱动单元)播放声音信号。举例来说,使用者会佩戴蓝牙耳机以聆听手机播放的音乐。然而,当使用者因为某些原因(例如与人交谈)暂时卸下蓝牙耳机时,蓝牙耳机仍会持续播放音乐,这不仅增加不必要的耗电,而且缩短电池的寿命。Existing audio playback systems use an audio playback driver/transducer (such as a playback drive unit of a speaker or earphone) to play a sound signal. For example, a user wears a Bluetooth headset to listen to music played on the phone. However, when the user temporarily removes the Bluetooth headset for some reason (for example, talking with a person), the Bluetooth headset continues to play music, which not only increases unnecessary power consumption, but also shortens the life of the battery.
因此,需要一种创新的音频播放侦测机制,其可检测音频播放系统/音频播放驱动单元的使用情境以调整其操作状态(例如选择性地进入省电模式),实现智能音频播放系统。Therefore, there is a need for an innovative audio playback detection mechanism that can detect the usage context of an audio playback system/audio playback driver unit to adjust its operational state (e.g., selectively enter a power save mode) to implement an intelligent audio playback system.
发明内容Summary of the invention
本发明的目的之一在于公开一种用于侦测音频播放驱动单元是否位于预定共振环境的侦测电路及其相关的方法,来解决上述问题。One of the objects of the present invention is to disclose a detection circuit for detecting whether an audio playback drive unit is located in a predetermined resonance environment and related methods to solve the above problems.
本发明的另一目的在于公开一种侦测电路及其相关的方法,其可根据音频播放驱动单元所处在的共振环境提供适合的音频播放质量, 满足使用者的聆听需求。Another object of the present invention is to disclose a detection circuit and related method that can provide suitable audio playback quality according to the resonant environment in which the audio playback drive unit is located, to meet the listening needs of the user.
本发明的一实施例公开了一种侦测电路。所述侦测电路包含传输电路以及处理电路。所述传输电路用以接收第一声音信号,并耦接于音频播放驱动单元,其中所述传输电路根据所述第一声音信号产生第二声音信号至所述音频播放驱动单元,以及至少根据所述第一声音信号与所述第二声音信号产生特征信号。所述处理电路耦接于所述传输电路以接收所述特征信号,所述处理电路至少根据所述第一声音信号与所述特征信号检测所述音频播放驱动单元是否位于预定共振环境。An embodiment of the invention discloses a detection circuit. The detection circuit includes a transmission circuit and a processing circuit. The transmission circuit is configured to receive a first sound signal and is coupled to the audio playback driving unit, wherein the transmission circuit generates a second sound signal according to the first sound signal to the audio playback driving unit, and at least according to the The first sound signal and the second sound signal generate a characteristic signal. The processing circuit is coupled to the transmission circuit to receive the characteristic signal, and the processing circuit detects whether the audio playback driving unit is located in a predetermined resonance environment according to at least the first sound signal and the characteristic signal.
本发明的一实施例公开了一种侦测方法。所述方法包含以下步骤:将第一声音信号馈入音频播放驱动单元所耦接的第一传输路径,以产生第二声音信号至所述音频播放驱动单元;至少根据所述第一声音信号与所述第二声音信号,于所述音频播放驱动单元所耦接的第二传输路径产生特征信号,其中所述第二传输路径不同于所述第一传输路径;以及至少根据所述第一声音信号与所述特征信号检测所述音频播放驱动单元是否位于预定共振环境。An embodiment of the invention discloses a detection method. The method includes the steps of: feeding a first sound signal to a first transmission path coupled to an audio playback driving unit to generate a second sound signal to the audio playback driving unit; at least according to the first sound signal Generating, by the second sound signal, a feature signal on a second transmission path coupled to the audio playback driving unit, wherein the second transmission path is different from the first transmission path; and at least according to the first sound The signal and the characteristic signal detect whether the audio playback drive unit is in a predetermined resonance environment.
附图说明DRAWINGS
图1是本发明实施例的音频播放系统的功能方框示意图。1 is a functional block diagram of an audio playback system in accordance with an embodiment of the present invention.
图2是图1所示的音频播放系统的一实施例的示意图。2 is a schematic diagram of an embodiment of the audio playback system shown in FIG. 1.
图3是本发明实施例用于侦测音频播放驱动单元是否位于预定共振环境的方法的流程图。3 is a flow chart of a method for detecting whether an audio playback drive unit is located in a predetermined resonance environment according to an embodiment of the present invention.
其中,附图标记说明如下:Among them, the reference numerals are as follows:
100、200                        音频播放系统100, 200 audio playback system
102、202                        音频播放驱动单元102, 202 audio playback drive unit
104、204                           侦测电路104, 204 detection circuit
106、206                           信号产生电路106, 206 signal generation circuit
110、210                           传输电路110, 210 transmission circuit
120、220                           处理电路120, 220 processing circuit
207                                数字信号处理电路207 digital signal processing circuit
208                                数模转换器208 digital to analog converter
209                                输出单元209 output unit
212、214、216                      传输路径212, 214, 216 transmission path
222                                输入单元222 input unit
224                                模数转换器224 analog to digital converter
226                                阻抗检测器226 impedance detector
310、320、330、340                 步骤310, 320, 330, 340 steps
P1、IP                             输入端口P1, IP input port
P2、P3、OP1、OP2                   输出端口P2, P3, OP1, OP2 output ports
Z_I1、Z_I2、Z_R1、Z_R2、Z_X1、Z_X2 阻抗Z_I1, Z_I2, Z_R1, Z_R2, Z_X1, Z_X2 impedance
Z_Load                             预定输入阻抗Z_Load predetermined input impedance
RS1、RS2                           共振腔RS1, RS2 resonator
AS1、AS2、TD、TA、SL               声音信号AS1, AS2, TD, TA, SL sound signals
SN                                 噪声信号SN noise signal
CHS、RD、RA                        特征信号CHS, RD, RA characteristic signals
CS                                 控制信号CS control signal
具体实施方式Detailed ways
本发明所公开的音频播放侦测机制可通过侦测音频播放驱动单元在声音输入侧的信号响应,将音频播放驱动单元作为周遭环境的传感装置,以检测音频播放驱动单元所处在的共振环境(或共振腔的几何结构/形状)。进一步的说明如下。The audio playback detection mechanism disclosed by the present invention can detect the signal response of the audio playback driving unit on the sound input side, and use the audio playback driving unit as a sensing device of the surrounding environment to detect the resonance of the audio playback driving unit. Environment (or geometry/shape of the cavity). Further explanation is as follows.
图1是本发明实施例的音频播放系统的功能方框示意图。于此实 施例中,音频播放系统100包含(但不限于)音频播放驱动单元(或音频播放换能器)102、侦测电路104以及信号产生电路106,其中音频播放系统100的至少一部份可由具有音频播放功能的电子装置来实施。例如,音频播放驱动单元102、侦测电路104与信号产生电路106可以是电子装置(诸如手机、掌上电脑或笔记本电脑)的至少一部份,其中音频播放驱动单元102是内置于该电子装置的播放驱动单元(诸如喇叭或耳机的播放驱动单元);又例如:侦测电路104与信号产生电路106可以是电子装置(诸如手机、掌上电脑或笔记本电脑)的至少一部份,而音频播放驱动单元102可以是外接于该电子装置的播放驱动单元(诸如喇叭或耳机的播放驱动单元);又例如,信号产生电路106可以是电子装置(诸如手机、掌上电脑或笔记本电脑)的至少一部份,而音频播放驱动单元102与侦测电路104可位于该电子装置所外接的音频播放装置(诸如喇叭或耳机)之中。1 is a functional block diagram of an audio playback system in accordance with an embodiment of the present invention. In this embodiment, the audio playback system 100 includes, but is not limited to, an audio playback driver unit (or audio playback transducer) 102, a detection circuit 104, and a signal generation circuit 106, wherein at least a portion of the audio playback system 100 It can be implemented by an electronic device having an audio playback function. For example, the audio playback driving unit 102, the detecting circuit 104, and the signal generating circuit 106 may be at least a part of an electronic device (such as a mobile phone, a palmtop computer, or a notebook computer), wherein the audio playback driving unit 102 is built in the electronic device. Playing a driving unit (such as a playback drive unit of a speaker or a headphone); for example, the detecting circuit 104 and the signal generating circuit 106 may be at least a part of an electronic device such as a mobile phone, a palmtop computer or a notebook computer, and the audio playback driver The unit 102 may be a playback drive unit (such as a playback drive unit of a speaker or an earphone) externally connected to the electronic device; for example, the signal generation circuit 106 may be at least a part of an electronic device such as a mobile phone, a palmtop computer or a notebook computer. The audio playback driving unit 102 and the detecting circuit 104 can be located in an audio playing device (such as a speaker or an earphone) external to the electronic device.
音频播放驱动单元102所处在的共振环境可影响其信号响应,而侦测电路104可根据音频播放驱动单元102的信号响应侦测音频播放驱动单元102所处在的共振环境(例如,是否位于一预定共振环境)。举例来说,在音频播放驱动单元102是由耳机的播放驱动单元来实施的情形下,当音频播放驱动单元102处在第一共振环境时(例如,使用者佩戴所述耳机),音频播放驱动单元102的共振腔具有第一几何结构/形状(例如,音频播放驱动单元102固有的几何共振空间结合使用者的耳道几何空间),音频播放驱动单元102的输入阻抗可具有第一频率响应特性;当音频播放驱动单元102处在第二共振环境时(例如,使用者卸下所述耳机),音频播放驱动单元102的共振腔具有第二几何结构/形状(例如,音频播放驱动单元102固有的几何共振空间),音频播放驱动单元102的输入阻抗可具有第二频率响应特性。因此,侦测电路104可通过侦测音频播放驱动单元102的输入阻抗或频率响应,检测音频播放驱动单元102所处在的共振环境(或使用情境)。The resonance environment in which the audio playback driving unit 102 is located may affect its signal response, and the detecting circuit 104 may detect the resonance environment in which the audio playback driving unit 102 is located according to the signal response of the audio playback driving unit 102 (for example, whether it is located or not) a predetermined resonance environment). For example, in the case where the audio playback driving unit 102 is implemented by the playback driving unit of the earphone, when the audio playback driving unit 102 is in the first resonance environment (for example, the user wears the earphone), the audio playback driver The resonant cavity of unit 102 has a first geometry/shape (eg, the geometric resonant space inherent to audio playback drive unit 102 in conjunction with the ear canal geometry of the user), and the input impedance of audio playback drive unit 102 can have a first frequency response characteristic When the audio playback drive unit 102 is in the second resonance environment (eg, the user removes the headphones), the resonant cavity of the audio playback drive unit 102 has a second geometry/shape (eg, inherent to the audio playback drive unit 102) The geometric resonance space), the input impedance of the audio playback drive unit 102 can have a second frequency response characteristic. Therefore, the detecting circuit 104 can detect the resonance environment (or use context) in which the audio playback driving unit 102 is located by detecting the input impedance or frequency response of the audio playback driving unit 102.
在此实施例中,侦测电路104根据信号产生电路106所提供的声音信号AS1输出声音信号AS2给音频播放驱动单元102,从而检测音频播放驱动单元102的输入阻抗/频率响应。侦测电路104包含(但不限于)传输电路110和处理电路120。传输电路110耦接于音频播放驱动单元102与信号产生电路106之间,用以接收声音信号AS1,并且将声音信号AS1朝音频播放驱动单元102传输,从而产生声音信号AS2以及获得特征信号CHS,其中传输电路110可根据声音信号AS1与声音信号AS2产生特征信号CHS。举例来说(但本发明不限于此),传输电路110包含输入端口P1、输出端口P2及输出端口P3。输入端口P1用以接收声音信号AS1,输出端口P2耦接于音频播放驱动单元102,而输出端口P3则是耦接于处理电路120。传输电路110可根据声音信号AS1产生声音信号AS2,通过输出端口P2输出至音频播放驱动单元102,以及至少根据声音信号AS1与声音信号AS2产生特征信号CHS,通过输出端口P3输出至处理电路120。In this embodiment, the detecting circuit 104 outputs the sound signal AS2 to the audio playback driving unit 102 based on the sound signal AS1 supplied from the signal generating circuit 106, thereby detecting the input impedance/frequency response of the audio playback driving unit 102. The detection circuit 104 includes, but is not limited to, a transmission circuit 110 and a processing circuit 120. The transmission circuit 110 is coupled between the audio playback driving unit 102 and the signal generating circuit 106 for receiving the sound signal AS1, and transmits the sound signal AS1 to the audio playback driving unit 102, thereby generating the sound signal AS2 and obtaining the characteristic signal CHS. The transmission circuit 110 can generate the characteristic signal CHS according to the sound signal AS1 and the sound signal AS2. For example (but the invention is not limited thereto), the transmission circuit 110 includes an input port P1, an output port P2, and an output port P3. The input port P1 is configured to receive the sound signal AS1, the output port P2 is coupled to the audio playback drive unit 102, and the output port P3 is coupled to the processing circuit 120. The transmission circuit 110 can generate the sound signal AS2 according to the sound signal AS1, output to the audio playback driving unit 102 through the output port P2, and generate the characteristic signal CHS based on at least the sound signal AS1 and the sound signal AS2, and output to the processing circuit 120 through the output port P3.
处理电路120耦接于传输电路110与信号产生电路106,用以接收特征信号CHS,以及至少根据声音信号AS1与特征信号CHS检测音频播放驱动单元102是否位于预定共振环境(例如,检测使用者是否佩戴包含音频播放驱动单元102的音频播放装置)。举例来说(但本发明不限于此),处理电路120可根据特征信号CHS与声音信号AS1的信号强度信息、相位信息和/或增益信息,侦测音频播放驱动单元102的输入阻抗或频率响应,从而检测音频播放驱动单元102是否位于预定共振环境。在具体实施方式中,当特征信号CHS相对于声音信号AS1的信号强度介于一强度特征范围内,且特征信号CHS相对于声音信号AS1的相位变化介于一相位特征范围内时,处理电路120可判断音频播放驱动单元102位于所述预定共振环境;当特征信号CHS的信号强度相对于声音信号AS1的信号强度未介于所述强度特征范围内,或特征信号CHS相对于声音信号AS1的相位变化未介于所述相位 特征范围内时,处理电路120可判断音频播放驱动单元102不位于所述预定共振环境。然而,本发明并不以此为限。The processing circuit 120 is coupled to the transmission circuit 110 and the signal generating circuit 106 for receiving the characteristic signal CHS, and detecting whether the audio playback driving unit 102 is located in a predetermined resonance environment according to at least the sound signal AS1 and the characteristic signal CHS (for example, detecting whether the user is The audio playback device including the audio playback drive unit 102 is worn. For example (but the invention is not limited thereto), the processing circuit 120 can detect the input impedance or frequency response of the audio playback driving unit 102 according to the signal strength information, phase information, and/or gain information of the characteristic signal CHS and the sound signal AS1. Thereby detecting whether the audio playback drive unit 102 is in a predetermined resonance environment. In a specific implementation, when the signal strength of the feature signal CHS relative to the sound signal AS1 is within a range of intensity characteristics, and the phase change of the feature signal CHS relative to the sound signal AS1 is within a phase feature range, the processing circuit 120 It can be determined that the audio playback driving unit 102 is located in the predetermined resonance environment; when the signal strength of the characteristic signal CHS is not within the intensity characteristic range with respect to the signal strength of the sound signal AS1, or the phase of the characteristic signal CHS relative to the sound signal AS1 When the change is not within the phase feature range, the processing circuit 120 can determine that the audio playback drive unit 102 is not located in the predetermined resonance environment. However, the invention is not limited thereto.
值得注意的是,处理电路120可接收声音信号AS1以直接检测声音信号AS1与特征信号CHS,也可以接收声音信号AS0以间接检测声音信号AS1与特征信号CHS,其中声音信号AS0是声音信号AS1从信号产生电路106输出之前的待处理版本。也就是说,信号产生电路106可对声音信号AS0进行预处理(诸如数模转换操作)以产生声音信号AS1。相似地,处理电路120可以直接检测特征信号CHS,也可以先对特征信号CHS进行预处理(诸如模数转换操作),再检测处理后的特征信号CHS。简言之,只要可根据声音信号AS1与特征信号CHS侦测音频播放驱动单元102的信号响应以检测音频播放驱动单元102所处的共振环境,设计上相关的变化均遵循本发明的精神。It should be noted that the processing circuit 120 can receive the sound signal AS1 to directly detect the sound signal AS1 and the characteristic signal CHS, and can also receive the sound signal AS0 to indirectly detect the sound signal AS1 and the characteristic signal CHS, wherein the sound signal AS0 is the sound signal AS1 The signal generation circuit 106 outputs the previous pending version. That is, the signal generating circuit 106 may perform preprocessing (such as a digital-to-analog conversion operation) on the sound signal AS0 to generate the sound signal AS1. Similarly, the processing circuit 120 may directly detect the feature signal CHS, or may perform pre-processing (such as analog-to-digital conversion operation) on the feature signal CHS, and then detect the processed feature signal CHS. In short, as long as the signal response of the audio playback driving unit 102 can be detected based on the sound signal AS1 and the characteristic signal CHS to detect the resonance environment in which the audio playback driving unit 102 is located, design-related changes are in accordance with the spirit of the present invention.
此外,在某些实施例中,传输电路110可针对预定输入阻抗进行阻抗匹配,所述预定输入阻抗可以是音频播放驱动单元102在所述预定共振环境时的输入阻抗。处理电路120可根据声音信号AS1与特征信号CHS检测关于音频播放驱动单元102的输入阻抗的信号响应。例如,当检测出传输电路110所获得的特征信号CHS之中来自声音信号AS1的信号成分小于一预定比例时,这意味着音频播放驱动单元102目前具有的输入阻抗等于(或大致等于)所述预定输入阻抗,处理电路120便可判断音频播放驱动单元102位于所述预定共振环境。Moreover, in some embodiments, transmission circuit 110 can perform impedance matching for a predetermined input impedance, which can be an input impedance of audio playback drive unit 102 when in the predetermined resonant environment. The processing circuit 120 can detect a signal response with respect to the input impedance of the audio playback driving unit 102 based on the sound signal AS1 and the characteristic signal CHS. For example, when it is detected that the signal component from the sound signal AS1 among the characteristic signals CHS obtained by the transmission circuit 110 is less than a predetermined ratio, this means that the audio playback driving unit 102 currently has an input impedance equal to (or substantially equal to) the said The input impedance is predetermined, and the processing circuit 120 can determine that the audio playback drive unit 102 is in the predetermined resonant environment.
为了便于理解本发明的技术特征,以下采用一示范性电路结构来说明本发明所公开的音频播放侦测机制的细节。然而,这只是方便说明而已。任何采用基于图1所示的电路结构的实施方式均是可行的。请参阅图2,其为图1所示的音频播放系统100的实施例的示意图。音频播放系统200包含(但不限于)音频播放驱动单元202、侦测电 路204以及信号产生电路206,其中图1所示的音频播放驱动单元102、侦测电路104及信号产生电路106分别由音频播放驱动单元202、侦测电路204及信号产生电路206来实施。此外,侦测电路204包含传输电路210与处理电路220,其中图1所示的传输电路110与处理电路120可分别由传输电路210与处理电路220来实施。In order to facilitate the understanding of the technical features of the present invention, an exemplary circuit structure is used below to illustrate the details of the disclosed audio playback detection mechanism. However, this is only a convenient explanation. Any implementation employing a circuit structure based on Figure 1 is feasible. Please refer to FIG. 2, which is a schematic diagram of an embodiment of the audio playback system 100 shown in FIG. 1. The audio playback system 200 includes, but is not limited to, an audio playback driver unit 202, a detection circuit 204, and a signal generation circuit 206, wherein the audio playback driver unit 102, the detection circuit 104, and the signal generation circuit 106 shown in FIG. The playback drive unit 202, the detection circuit 204, and the signal generation circuit 206 are implemented. In addition, the detection circuit 204 includes a transmission circuit 210 and a processing circuit 220. The transmission circuit 110 and the processing circuit 120 shown in FIG. 1 can be implemented by the transmission circuit 210 and the processing circuit 220, respectively.
于此实施例中,信号产生电路206包含(但不限于)数字信号处理电路207、数模转换器208(标示为“DAC”)以及输出单元209(标示为“BF1”),其中输出单元209可由功率放大器来实施。数字信号处理电路207产生声音信号TD(数字声音信号)给数模转换器208。在通过数模转换器208和输出单元209相关的处理之后,声音信号TD可转换为声音信号TA(模拟声音信号)。In this embodiment, signal generation circuit 206 includes, but is not limited to, digital signal processing circuit 207, digital to analog converter 208 (labeled "DAC"), and output unit 209 (labeled "BF1"), where output unit 209 It can be implemented by a power amplifier. The digital signal processing circuit 207 generates a sound signal TD (digital sound signal) to the digital to analog converter 208. After the processing by the digital-to-analog converter 208 and the output unit 209, the sound signal TD can be converted into a sound signal TA (analog sound signal).
声音信号TA在通过传输电路210后形成声音信号SL至音频播放驱动单元202,声音信号SL会根据音频播放驱动单元202的输入阻抗的变化而改变。传输电路210还根据声音信号TA与声音信号SL产生特征信号RA至处理电路220。于此实施例中,传输电路210可通过电路匹配的方式检测音频播放驱动单元202的信号响应(或输入阻抗变化)。举例来说(但本发明不限于此),传输电路210可由混合匹配网络(hybrid matching network)来实施(诸如混合阻抗匹配电路(hybrid impedance matching circuit)),并且可包含输入端口IP、输出端口OP1、输出端口OP2以及多个传输路径212-216,其中传输路径212耦接于输入端口IP与输出端口OP1之间,传输路径214耦接于输出端口OP1与输出端口OP2之间,以及传输路径216耦接于输入端口IP与输出端口OP2之间。The sound signal TA forms a sound signal SL to the audio playback driving unit 202 after passing through the transmission circuit 210, and the sound signal SL changes according to a change in the input impedance of the audio playback driving unit 202. The transmission circuit 210 also generates a characteristic signal RA to the processing circuit 220 based on the sound signal TA and the sound signal SL. In this embodiment, the transmission circuit 210 can detect the signal response (or input impedance variation) of the audio playback driving unit 202 by means of circuit matching. For example (but the invention is not limited thereto), the transmission circuit 210 may be implemented by a hybrid matching network (such as a hybrid impedance matching circuit), and may include an input port IP and an output port OP1. The output port OP2 and the plurality of transmission paths 212-216, wherein the transmission path 212 is coupled between the input port IP and the output port OP1, the transmission path 214 is coupled between the output port OP1 and the output port OP2, and the transmission path 216 It is coupled between the input port IP and the output port OP2.
处理电路220包含(但不限于)输入单元222(标示为“BF2”)、模数转换器224(标示为“ADC”)以及阻抗检测器226,其中输入单 元222可由缓冲器来实施。模数转换器224可将输入单元222所缓冲的特征信号RA(模拟信号)进行转换以产生特征信号RD(数字信号),阻抗检测器226便可根据声音信号TA对应的数字版本(声音信号TD)与特征信号RA对应的数字版本(特征信号RD)检测音频播放驱动单元202是否位于预定共振环境。 Processing circuit 220 includes, but is not limited to, input unit 222 (labeled "BF2"), analog to digital converter 224 (labeled "ADC"), and impedance detector 226, where input unit 222 can be implemented by a buffer. The analog-to-digital converter 224 can convert the characteristic signal RA (analog signal) buffered by the input unit 222 to generate a characteristic signal RD (digital signal), and the impedance detector 226 can be based on the digital version corresponding to the sound signal TA (sound signal TD) The digital version (feature signal RD) corresponding to the feature signal RA detects whether the audio playback drive unit 202 is in a predetermined resonance environment.
值得注意的是,在某些实施例中,输出单元209的输出阻抗(或信号产生电路206的输出阻抗)相对于音频播放驱动单元202的输入阻抗(信号产生电路206的电气负载的阻抗)来说是很小的,因此,根据音频播放驱动单元202的共振环境(共振腔几何结构/形状)的改变而产生不同的信号响应(诸如特征信号RA的响应特性),阻抗检测器226可检测出音频播放驱动单元202的输入阻抗变化,从而判断音频播放驱动单元202所处在的共振环境。It should be noted that in some embodiments, the output impedance of the output unit 209 (or the output impedance of the signal generating circuit 206) is relative to the input impedance of the audio playback driving unit 202 (the impedance of the electrical load of the signal generating circuit 206). It is said to be small, therefore, different signal responses (such as response characteristics of the characteristic signal RA) are generated according to changes in the resonant environment (resonator geometry/shape) of the audio playback drive unit 202, and the impedance detector 226 can detect The input impedance of the audio playback drive unit 202 changes, thereby determining the resonant environment in which the audio playback drive unit 202 is located.
举例来说,输入端口IP与输出端口OP1之间所具有的传输阻抗(传输路径212所具有的传输阻抗)可匹配于一预定输入阻抗Z_Load,其中预定输入阻抗Z_Load是音频播放驱动单元202位于所述预定共振环境下(对应于共振腔RS1)从输出端口OP1看进去的输入阻抗,而阻抗Z_I1与阻抗Z_I2均可等于(但不限于)预定输入阻抗Z_Load的二分之一。此外,通过适当的设计,当音频播放驱动单元202位于所述预定共振环境时,输出端口OP1与输出端口OP2之间所具有的传输阻抗(传输路径214所具有的传输阻抗)以及输入端口IP与输出端口OP2之间所具有的传输阻抗(传输路径216所具有的传输阻抗)可使特征信号RA之中来自声音信号TA的信号成分大幅减少。例如,输出端口OP1与输出端口OP2之间的传输阻抗可以是(但不限于)输入端口IP与输出端口OP2之间的传输阻抗的二分之一,以使通过传输路径214传递至输出端口OP2的信号(对应于声音信号SL)可抵消(或大致抵销)通过传输路径216传递至输出端口OP2的信号(对应于声音信号TA),其中阻抗Z_R1可等于阻抗Z_R2,阻抗 Z_X1可等于阻抗Z_X2,以及阻抗Z_R1与阻抗Z_R2均可等于阻抗Z_X1(阻抗Z_X2)的二分之一。相对于声音信号TA本身的信号强度,特征信号RA受到声音信号TA的影响很小,声音信号TA的信号强度会衰减许多(或衰减为零)。也就是说,在某些电路匹配的情形下,声音信号TA的存在(或变化)等效上不会(或几乎不会)对输出端口OP2产生的信号造成影响。For example, the transmission impedance between the input port IP and the output port OP1 (the transmission impedance of the transmission path 212) can be matched to a predetermined input impedance Z_Load, wherein the predetermined input impedance Z_Load is the audio playback driving unit 202 located at the The input impedance is seen from the output port OP1 in a predetermined resonance environment (corresponding to the resonant cavity RS1), and the impedance Z_I1 and the impedance Z_I2 may both be equal to, but not limited to, one-half of the predetermined input impedance Z_Load. Further, by appropriate design, when the audio playback driving unit 202 is located in the predetermined resonance environment, the transmission impedance between the output port OP1 and the output port OP2 (the transmission impedance of the transmission path 214) and the input port IP and The transmission impedance between the output ports OP2 (the transmission impedance of the transmission path 216) can greatly reduce the signal component from the sound signal TA among the characteristic signals RA. For example, the transmission impedance between the output port OP1 and the output port OP2 may be, but is not limited to, one-half of the transmission impedance between the input port IP and the output port OP2 to be passed through the transmission path 214 to the output port OP2. The signal (corresponding to the sound signal SL) can cancel (or substantially cancel) the signal (corresponding to the sound signal TA) transmitted to the output port OP2 through the transmission path 216, wherein the impedance Z_R1 can be equal to the impedance Z_R2, and the impedance Z_X1 can be equal to the impedance Z_X2 And the impedance Z_R1 and the impedance Z_R2 can both be equal to one-half of the impedance Z_X1 (impedance Z_X2). Relative to the signal strength of the sound signal TA itself, the characteristic signal RA is less affected by the sound signal TA, and the signal strength of the sound signal TA is attenuated a lot (or attenuated to zero). That is to say, in the case of some circuit matching, the presence (or variation) of the sound signal TA equivalently does not (or hardly affect) the signal generated by the output port OP2.
此外,由于声音信号TA的存在(或变化)于某些电路匹配的情形下不会(或几乎不会)对输出端口OP2产生的信号造成影响,因此,从另一方面来说,于输出端口OP2产生的特征信号RA对于电路匹配情形的变化可具有很高的灵敏度。例如,特征信号RA对于音频播放驱动单元202输入阻抗的变化(电路匹配的情形随之改变)会很灵敏。In addition, since the presence (or variation) of the sound signal TA does not (or hardly affect) the signal generated by the output port OP2 in the case of some circuit matching, on the other hand, on the output port The characteristic signal RA generated by OP2 can have a high sensitivity to changes in the circuit matching situation. For example, the characteristic signal RA can be very sensitive to changes in the input impedance of the audio playback drive unit 202 (the situation in which the circuit matching changes).
因此,当阻抗检测器226检测出特征信号RD相对于声音信号TD的信号强度介于一强度特征范围内时(例如,相比于声音信号TD,特征信号RD的信号强度衰减超过20分贝,或衰减介于20分贝与40分贝之间),其意味着传输电路210通过阻抗匹配已大幅减少特征信号RA之中来自声音信号TA的信号成分,阻抗检测器226(或处理电路220)便可检测出音频播放驱动单元202位于所述预定共振环境。此外,当阻抗检测器226检测出特征信号RD相对于声音信号TD的信号强度未介于所述强度特征范围内时,阻抗检测器226(或处理电路220)则可检测出音频播放驱动单元202不位于所述预定共振环境。举例来说,当阻抗检测器226检测出特征信号RD相对于声音信号TD的信号强度未介于所述强度特征范围内但介于另一强度特征范围内时,阻抗检测器226(或处理电路220)可检测出音频播放驱动单元202位于另一预定共振环境(对应于另一共振腔RS2),其中共振腔RS1所对应的预定共振环境可以是(但不限于)使用者佩戴包含音频播放驱动单元202的耳机,共振腔RS2所对应的预定共振环境可以是(但不限于)使用者卸下包含音频播放驱动单元202的耳机。Therefore, when the impedance detector 226 detects that the signal strength of the characteristic signal RD with respect to the sound signal TD is within a range of intensity characteristics (eg, the signal strength of the characteristic signal RD is attenuated by more than 20 decibels compared to the sound signal TD, or The attenuation is between 20 decibels and 40 decibels, which means that the transmission circuit 210 has greatly reduced the signal component from the sound signal TA among the characteristic signals RA by impedance matching, and the impedance detector 226 (or the processing circuit 220) can detect The outgoing audio playback drive unit 202 is located in the predetermined resonant environment. In addition, when the impedance detector 226 detects that the signal strength of the feature signal RD with respect to the sound signal TD is not within the intensity characteristic range, the impedance detector 226 (or the processing circuit 220) can detect the audio playback driving unit 202. Not located in the predetermined resonant environment. For example, when the impedance detector 226 detects that the signal strength of the feature signal RD relative to the sound signal TD is not within the intensity feature range but is within another intensity feature range, the impedance detector 226 (or processing circuit) 220) It can be detected that the audio playback driving unit 202 is located in another predetermined resonance environment (corresponding to another resonant cavity RS2), wherein the predetermined resonance environment corresponding to the resonant cavity RS1 can be, but is not limited to, the user wears the audio playback driver. In the earphone of unit 202, the predetermined resonance environment corresponding to the resonant cavity RS2 may be, but is not limited to, the user removing the earphone including the audio playback driving unit 202.
在某些实施例中,当阻抗检测器226检测出特征信号RD相对于声音信号TD的相位变化介于一相位特征范围内时(例如,相比于声音信号TD,特征信号RD的相位变化超过一预定角度,或介于一预定变化范围内),其意味着传输电路210通过阻抗匹配已大幅减少特征信号RA之中来自声音信号TA的信号成分,或意味着音频播放驱动单元202的共振腔处于一特定共振频率或同时处于多个共振频率(泛音),阻抗检测器226(或处理电路220)便可检测出音频播放驱动单元202位于所述预定共振环境。当阻抗检测器226检测出特征信号RD相对于声音信号TD的相位变化未介于所述相位特征范围内时,阻抗检测器226(或处理电路220)则可检测出音频播放驱动单元202不位于所述预定共振环境。In some embodiments, when the impedance detector 226 detects that the phase change of the feature signal RD relative to the sound signal TD is within a phase feature range (eg, the phase change of the feature signal RD exceeds the sound signal TD) a predetermined angle, or within a predetermined range of variation, which means that the transmission circuit 210 has substantially reduced the signal component from the sound signal TA among the characteristic signals RA by impedance matching, or means that the cavity of the audio playback driving unit 202 At a particular resonant frequency or at multiple resonant frequencies (overtones) at the same time, impedance detector 226 (or processing circuit 220) can detect that audio playback drive unit 202 is in the predetermined resonant environment. When the impedance detector 226 detects that the phase change of the characteristic signal RD with respect to the sound signal TD is not within the phase characteristic range, the impedance detector 226 (or the processing circuit 220) can detect that the audio playback driving unit 202 is not located. The predetermined resonance environment.
再者,在某些实施例中,当阻抗检测器226检测出特征信号RD相对于声音信号TD的信号强度介于一强度特征范围内,且特征信号RD相对于声音信号TD的相位变化介于一相位特征范围内时(例如,相比于声音信号TD,特征信号RD的信号强度衰减超过20分贝,且特征信号RD的相位变化介于一预定变化范围内),其意味着传输电路210通过阻抗匹配已大幅减少特征信号RA之中来自声音信号TA的信号成分,或意味着音频播放驱动单元202的共振腔可能处于一特定共振频率或同时处于多个共振频率,阻抗检测器226(或处理电路220)便可检测出音频播放驱动单元202位于所述预定共振环境。当阻抗检测器226检测出特征信号RD相对于声音信号TD的信号强度未介于所述强度特征范围内,且特征信号RD相对于声音信号TD的相位变化未介于所述相位特征范围内时,阻抗检测器226(或处理电路220)则可检测出音频播放驱动单元202不位于所述预定共振环境。Moreover, in some embodiments, when the impedance detector 226 detects that the signal strength of the characteristic signal RD relative to the sound signal TD is within a range of intensity characteristics, and the phase change of the characteristic signal RD relative to the sound signal TD is between When the phase characteristic range is within (for example, the signal strength of the characteristic signal RD is attenuated by more than 20 decibels compared to the sound signal TD, and the phase change of the characteristic signal RD is within a predetermined variation range), which means that the transmission circuit 210 passes Impedance matching has substantially reduced the signal component from the sound signal TA among the characteristic signals RA, or means that the resonant cavity of the audio playback drive unit 202 may be at a particular resonant frequency or at multiple resonant frequencies simultaneously, the impedance detector 226 (or processing) The circuit 220) can detect that the audio playback drive unit 202 is in the predetermined resonant environment. When the impedance detector 226 detects that the signal strength of the characteristic signal RD with respect to the sound signal TD is not within the intensity characteristic range, and the phase change of the characteristic signal RD with respect to the sound signal TD is not within the phase characteristic range The impedance detector 226 (or processing circuit 220) can then detect that the audio playback drive unit 202 is not located in the predetermined resonant environment.
简言之,当音频播放驱动单元202所处的共振环境改变时,传输电路210所产生的特征信号RA可反映音频播放驱动单元202的输入 阻抗变化,阻抗检测器226便可从所获得的信号特征(诸如信号强度和/或相位变化)检测出音频播放驱动单元202目前所处在的共振环境。In short, when the resonance environment in which the audio playback driving unit 202 is located changes, the characteristic signal RA generated by the transmission circuit 210 can reflect the input impedance change of the audio playback driving unit 202, and the impedance detector 226 can obtain the obtained signal. Features such as signal strength and/or phase changes detect the resonant environment in which the audio playback drive unit 202 is currently located.
值得注意的是,在某些实施例中,传输电路210可针对预定输入阻抗Z_Load于一特定频率范围进行阻抗匹配,其中所述特定频率范围可以位于人耳可感知的频率范围之内或之外。举例来说,在音频播放驱动单元202用于播放频率范围位于可听声波(audible sound)的频率范围内的声音信号(即人耳可感知的音频信号,诸如信号产生电路206所产生的交响乐曲音频信号)的情形下,处理电路220可同时根据所述声音信号(由信号产生电路206所产生)的频率响应来检测音频播放驱动单元202所处的共振环境,或者是根据信号产生电路206所产生的另一声音信号(例如,超声波信号)的频率响应来检测音频播放驱动单元202所处的共振环境。换句话说,所述特定频率范围可以包含超声波的频率范围和可听声波的频率范围的至少其一。It should be noted that in some embodiments, the transmission circuit 210 may perform impedance matching for a predetermined frequency range Z_Load over a specific frequency range, wherein the specific frequency range may be within or outside the range of frequencies perceived by the human ear. . For example, the audio playback driving unit 202 is configured to play a sound signal whose frequency range is within an audible sound frequency range (ie, an ear-perceivable audio signal, such as a symphony generated by the signal generating circuit 206). In the case of an audio signal), the processing circuit 220 can simultaneously detect the resonance environment in which the audio playback driving unit 202 is located according to the frequency response of the sound signal (generated by the signal generation circuit 206), or according to the signal generation circuit 206. The frequency response of another generated sound signal (e.g., ultrasonic signal) is detected to detect the resonant environment in which the audio playback drive unit 202 is located. In other words, the specific frequency range may include at least one of a frequency range of the ultrasonic waves and a frequency range of the audible sound waves.
此外,在某些实施例中,传输电路210可能通过输出端口OP1从音频播放驱动单元202接收噪声信号SN,其中噪声信号SN可以是周遭环境的声音信号(诸如人体的心跳声或讲话声)。也就是说,特征信号RA可包含来自噪声信号SN的信号成分。由于侦测电路204可灵敏地侦测音频播放驱动单元202因应共振环境的改变而产生的输入阻抗变化(或频率响应),因此,传输电路210所产生的特征信号RA仍可反映音频播放驱动单元202的输入阻抗变化(例如,相对于声音信号TD的信号强度,特征信号RD的信号强度大幅衰减),使得阻抗检测器226可根据特征信号RA和声音信号TA(或特征信号RD和特征信号TD)检测音频播放驱动单元202目前所处在的共振环境,而不易受到噪声信号SN的干扰。Moreover, in some embodiments, transmission circuit 210 may receive noise signal SN from audio playback drive unit 202 via output port OP1, which may be a sound signal of a surrounding environment (such as a heartbeat or speech sound of a human body). That is to say, the characteristic signal RA may contain a signal component from the noise signal SN. Since the detecting circuit 204 can sensitively detect the input impedance change (or frequency response) generated by the audio playback driving unit 202 in response to the change of the resonance environment, the characteristic signal RA generated by the transmission circuit 210 can still reflect the audio playback driving unit. The input impedance variation of 202 (eg, the signal strength of the characteristic signal RD is substantially attenuated relative to the signal strength of the sound signal TD) such that the impedance detector 226 can be based on the characteristic signal RA and the sound signal TA (or the characteristic signal RD and the characteristic signal TD) The resonance environment in which the audio playback drive unit 202 is currently located is detected, and is not susceptible to interference by the noise signal SN.
请注意,以上仅供说明的目的,并非用来作为本发明的限制。在一设计变化例中,只要处理电路220可以侦测音频播放驱动单元202因为共振环境改变的缘故所造成的阻抗变化,省略多个传输路径212-216其中的至少一传输路径也是可行的。例如,在省略/移除传输路径216的情形下,阻抗检测器226可直接对声音信号TA/TD与特征信号RA/RD进行相关的数值演算,判断音频播放驱动单元202的输入阻抗变化。又例如,在省略/移除传输路径214和传输路径216的情形下,阻抗检测器226可直接对声音信号TA/TD与声音信号SL进行相关的数值演算,判断音频播放驱动单元202的输入阻抗变化。Please note that the above is for illustrative purposes only and is not intended to be a limitation of the invention. In a design variation, it is also possible to omit at least one of the plurality of transmission paths 212-216 as long as the processing circuit 220 can detect an impedance change caused by the change in the resonant environment of the audio playback drive unit 202. For example, in the case where the transmission path 216 is omitted/removed, the impedance detector 226 can directly perform a numerical calculation on the sound signal TA/TD and the characteristic signal RA/RD to determine the input impedance change of the audio playback driving unit 202. For another example, in the case of omitting/removing the transmission path 214 and the transmission path 216, the impedance detector 226 can directly perform a numerical calculation on the sound signal TA/TD and the sound signal SL to determine the input impedance of the audio playback driving unit 202. Variety.
在另一设计变化例中,处理电路220还可调整传输路径214的传输阻抗(诸如阻抗Z_R1和/或阻抗Z_R2)与传输路径216的传输阻抗(诸如阻抗Z_X1和/或阻抗Z_X2)两者之间的比例,以根据传输路径214的传输阻抗与传输路径216的传输阻抗两者之间的比例、声音信号TA与特征信号RA检测音频播放驱动单元202是否位于所述预定共振环境。举例来说(但本发明不限于此),阻抗Z_X1和阻抗Z_X2均可由一阻抗阵列来实施,其中阻抗检测器226可产生一控制信号CS给阻抗Z_X1和阻抗Z_X2以控制阻抗Z_X1和阻抗Z_X2的阻抗值,使得特征信号RA相对于声音信号TA的信号强度(或特征信号RD相对于声音信号TD的信号强度)介于一强度特征范围内,和/或特征信号RA相对于声音信号TA的相位变化(或特征信号RD相对于声音信号TD的相位变化)介于一相位特征范围内。当特征信号RA相对于声音信号TA的信号强度介于所述强度特征范围内,和/或特征信号RA相对于声音信号TA的相位变化(或特征信号RD相对于声音信号TD的相位变化)介于所述相位特征范围内时,阻抗检测器226可根据相对应的阻抗比例(诸如阻抗Z_X2与阻抗Z_R1两者之间的比例,及/或阻抗Z_X1与阻抗Z_R2两者之间的比例),检测音频播放驱动单元202是否位于所述预定共振环境。In another design variation, processing circuit 220 may also adjust the transmission impedance of transmission path 214 (such as impedance Z_R1 and/or impedance Z_R2) to the transmission impedance of transmission path 216 (such as impedance Z_X1 and/or impedance Z_X2). The ratio between the two is based on the ratio between the transmission impedance of the transmission path 214 and the transmission impedance of the transmission path 216, the sound signal TA and the characteristic signal RA to detect whether the audio playback driving unit 202 is located in the predetermined resonance environment. For example (but the invention is not limited thereto), the impedance Z_X1 and the impedance Z_X2 may each be implemented by an impedance array, wherein the impedance detector 226 may generate a control signal CS to the impedance Z_X1 and the impedance Z_X2 to control the impedance Z_X1 and the impedance Z_X2. The impedance value is such that the signal strength of the characteristic signal RA relative to the sound signal TA (or the signal strength of the characteristic signal RD relative to the sound signal TD) is within a range of intensity characteristics and/or the phase of the characteristic signal RA relative to the sound signal TA The change (or the phase change of the characteristic signal RD with respect to the sound signal TD) is within a range of phase characteristics. When the signal strength of the characteristic signal RA relative to the sound signal TA is within the intensity characteristic range, and/or the phase change of the characteristic signal RA with respect to the sound signal TA (or the phase change of the characteristic signal RD with respect to the sound signal TD) When in the phase characteristic range, the impedance detector 226 may be based on a corresponding impedance ratio (such as a ratio between the impedance Z_X2 and the impedance Z_R1, and/or a ratio between the impedance Z_X1 and the impedance Z_R2), It is detected whether the audio playback drive unit 202 is located in the predetermined resonance environment.
在又一设计变化例中,传输电路210也可以由其他电路结构来实施。举例来说,传输电路210可采用变压器来进行电路匹配,通过电流相减的方式,在音频播放驱动单元202位于所述预定共振环境的情形下,使得特征信号RA之中来自声音信号TA的信号成分大幅减少。In yet another design variant, the transmission circuit 210 can also be implemented by other circuit configurations. For example, the transmission circuit 210 may employ a transformer for circuit matching, and in a case of current subtraction, in a case where the audio playback driving unit 202 is located in the predetermined resonance environment, a signal from the sound signal TA among the characteristic signals RA is made. The composition has been greatly reduced.
本发明所公开的音频播放侦测机制可简单归纳为图3所示的流程图。请参阅图3,其为本发明用于侦测音频播放驱动单元是否位于预定共振环境的方法的流程图。假若所得到的结果实质上大致相同,则步骤不一定要按照图3所示的顺序来进行。举例来说,某些步骤可安插于其中。为了方便说明,以下搭配图2所示的音频播放系统200来说明图3所示的方法。然而,将图3所示的方法应用于图1所示的音频播放系统100也是可行的。所述方法可简单归纳如下。The audio playback detection mechanism disclosed in the present invention can be simply summarized into the flowchart shown in FIG. Please refer to FIG. 3, which is a flowchart of a method for detecting whether an audio playback driving unit is located in a predetermined resonance environment. If the results obtained are substantially the same, the steps do not have to be performed in the order shown in FIG. For example, some steps can be placed in it. For convenience of explanation, the method shown in FIG. 3 will be described below in conjunction with the audio playback system 200 shown in FIG. 2. However, it is also feasible to apply the method shown in FIG. 3 to the audio playback system 100 shown in FIG. 1. The method can be summarized as follows.
步骤310:开始。Step 310: Start.
例如,利用数字信号处理电路207产生声音信号TD,以及利用数模转换器208和输出单元209将声音信号TD转换为声音信号TA。For example, the sound signal TD is generated by the digital signal processing circuit 207, and the sound signal TD is converted into the sound signal TA by the digital-to-analog converter 208 and the output unit 209.
步骤320:将第一声音信号馈入所述音频播放驱动单元所耦接的第一传输路径,以产生第二声音信号至所述音频播放驱动单元。Step 320: Feed the first sound signal to the first transmission path coupled to the audio playback driving unit to generate a second sound signal to the audio playback driving unit.
例如,将声音信号TA馈入音频播放驱动单元202所耦接的传输路径212,以产生声音信号SL至音频播放驱动单元202。For example, the sound signal TA is fed to the transmission path 212 coupled to the audio playback driving unit 202 to generate the sound signal SL to the audio playback driving unit 202.
步骤330:至少根据所述第一声音信号与所述第二声音信号,于所述音频播放驱动单元所耦接的第二传输路径产生特征信号,其中所述第二传输路径不同于所述第一传输路径。Step 330: Generate a feature signal according to the second transmission path coupled to the audio playback driving unit, according to the first sound signal and the second sound signal, where the second transmission path is different from the first A transmission path.
例如,传输电路210至少根据声音信号TA与声音信号SL于音频 播放驱动单元202所耦接的传输路径214产生特征信号RA,其中传输路径214不同于传输路径212。For example, the transmission circuit 210 generates a characteristic signal RA based at least on the transmission path 214 to which the audio signal SL is coupled to the audio playback drive unit 202, wherein the transmission path 214 is different from the transmission path 212.
步骤340:至少根据所述第一声音信号与所述特征信号检测所述音频播放驱动单元是否位于所述预定共振环境。Step 340: Detect whether the audio playback driving unit is located in the predetermined resonance environment according to at least the first sound signal and the characteristic signal.
例如,处理电路220至少根据声音信号TA与特征信号RA检测音频播放驱动单元202是否位于所述预定共振环境。For example, the processing circuit 220 detects whether the audio playback drive unit 202 is located in the predetermined resonance environment based at least on the sound signal TA and the feature signal RA.
于步骤330中,传输电路210可将声音信号TA通过传输路径216耦接到传输路径214,以根据声音信号TA与声音信号SL于输出端口OP2产生特征信号RA。特征信号RA便可反映传输电路210与音频播放驱动单元202之间的电路匹配情形。此外,于某些实施例中,传输路径212、传输路径214与传输路径216用来对预定输入阻抗进行阻抗匹配,而所述预定输入阻抗是音频播放驱动单元202在所述预定共振环境时的输入阻抗(诸如预定输入阻抗Z_Load)。In step 330, the transmission circuit 210 can couple the sound signal TA to the transmission path 214 through the transmission path 216 to generate the characteristic signal RA at the output port OP2 according to the sound signal TA and the sound signal SL. The feature signal RA can reflect the circuit matching situation between the transmission circuit 210 and the audio playback drive unit 202. Moreover, in some embodiments, transmission path 212, transmission path 214, and transmission path 216 are used to impedance match a predetermined input impedance, and the predetermined input impedance is when audio playback drive unit 202 is in the predetermined resonant environment. Input impedance (such as a predetermined input impedance Z_Load).
于步骤340中,当特征信号RA相对于声音信号TA的信号强度介于一强度特征范围内(例如,阻抗检测器226检测出特征信号RD相对于声音信号TD的信号强度具有大量的衰减),和/或特征信号RA相对于声音信号TA的相位变化介于一相位特征范围内时,阻抗检测器226可判断音频播放驱动单元202位于所述预定共振环境;当特征信号RA相对于声音信号TA的信号强度未介于所述强度特征范围内,和/或特征信号RA相对于声音信号TA的相位变化未介于所述相位特征范围内时,阻抗检测器226可判断音频播放驱动单元202不位于所述预定共振环境。In step 340, when the signal strength of the feature signal RA relative to the sound signal TA is within a range of intensity characteristics (eg, the impedance detector 226 detects that the characteristic signal RD has a large amount of attenuation with respect to the signal strength of the sound signal TD), And/or when the phase change of the characteristic signal RA relative to the sound signal TA is within a phase characteristic range, the impedance detector 226 may determine that the audio playback driving unit 202 is located in the predetermined resonance environment; when the characteristic signal RA is relative to the sound signal TA When the signal strength is not within the range of the intensity characteristics, and/or the phase change of the characteristic signal RA relative to the sound signal TA is not within the phase feature range, the impedance detector 226 may determine that the audio playback driving unit 202 is not Located in the predetermined resonant environment.
由于本领域的技术人员通过阅读图1和图2相关的段落说明之后,应可了解图3所示的方法中每一步骤的细节,因此进一步的说明在此便不再赘述。Since the details of each step in the method shown in FIG. 3 should be understood by those skilled in the art after reading the relevant paragraphs of FIG. 1 and FIG. 2, further description will not be repeated here.
综上所述,本发明所公开的侦测电路及其相关的侦测方法可利用检测音频播放驱动单元的信号响应(诸如输入阻抗的变化),判断音频播放驱动单元所处在的共振环境(或判断音频播放驱动单元的共振腔几何结构/形状)。本发明所公开的音频侦测机制可具有多种应用。举例来说,本发明所公开的音频侦测机制可用于穿戴检测,以检测使用者是否佩戴具有所述音频播放驱动单元的音频播放装置,并且于使用者未佩戴所述音频播放装置时调整所述音频播放驱动单元的操作状态(例如进入省电模式),实现智能音频播放系统。于另一例子中,本发明所公开的音频侦测机制可检测用户的佩戴状态,诸如紧密地佩戴或轻轻地佩戴,以调整欲播放的声音信号(例如,调整声音信号的振幅)。本发明所公开的音频侦测机制可调整欲播放的声音信号(例如,调整高频和/或低频频段的信号特性),以提升音频播放质量。于又一例子中,通过检测音频播放驱动单元所处在的共振腔几何结构/形状,本发明所公开的音频侦测机制可用于辨识人耳耳道的结构特征。In summary, the detection circuit and related detection method disclosed by the present invention can detect the resonance environment of the audio playback driving unit by detecting the signal response of the audio playback driving unit (such as the change of the input impedance). Or determine the resonant cavity geometry/shape of the audio playback drive unit). The audio detection mechanism disclosed by the present invention can have a variety of applications. For example, the audio detection mechanism disclosed in the present invention can be used for wear detection to detect whether a user wears an audio playback device having the audio playback driving unit, and adjusts the user when the user does not wear the audio playback device. The operating state of the audio playback drive unit (for example, entering the power saving mode) implements an intelligent audio playback system. In another example, the disclosed audio detection mechanism can detect a user's wearing state, such as wearing it tightly or gently, to adjust the sound signal to be played (eg, adjusting the amplitude of the sound signal). The audio detection mechanism disclosed by the present invention can adjust the sound signal to be played (for example, adjusting the signal characteristics of the high frequency and/or low frequency bands) to improve the audio playback quality. In yet another example, the disclosed audio detection mechanism can be used to identify structural features of the human ear canal by detecting the resonant cavity geometry/shape in which the audio playback drive unit is located.
以上所述仅为本发明的优选实施例而已,并不用于限制本发明,对于本领域的技术人员来说,本发明可以有各种更改和变化。凡在本发明的精神和原则之内,所作的任何修改、等同替换、改进等,均应包含在本发明的保护范围之内。The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims (20)

  1. 一种侦测电路,其特征在于,包含:A detection circuit, comprising:
    传输电路,用以接收第一声音信号,并耦接于音频播放驱动单元,a transmission circuit, configured to receive the first sound signal, and coupled to the audio playback driving unit,
    其中所述传输电路根据所述第一声音信号产生第二声音信号至所述音频播放驱动单元,以及至少根据所述第一声音信号与所述第二声音信号产生特征信号;以及Wherein the transmission circuit generates a second sound signal to the audio playback driving unit according to the first sound signal, and generates a feature signal based on at least the first sound signal and the second sound signal;
    处理电路,耦接于所述传输电路以接收所述特征信号,a processing circuit coupled to the transmission circuit to receive the characteristic signal,
    所述处理电路至少根据所述第一声音信号与所述特征信号检测所述音频播放驱动单元是否位于预定共振环境。The processing circuit detects whether the audio playback driving unit is located in a predetermined resonance environment based on at least the first sound signal and the characteristic signal.
  2. 如权利要求1所述的侦测电路,其特征在于,所述传输电路针对预定输入阻抗进行阻抗匹配,所述预定输入阻抗为所述音频播放驱动单元在所述预定共振环境时的输入阻抗。The detection circuit of claim 1 wherein said transmission circuit performs impedance matching for a predetermined input impedance, said predetermined input impedance being an input impedance of said audio playback drive unit in said predetermined resonant environment.
  3. 如权利要求2所述的侦测电路,其特征在于,所述传输电路是混合阻抗匹配电路。The detection circuit of claim 2 wherein said transmission circuit is a hybrid impedance matching circuit.
  4. 如权利要求2所述的侦测电路,其特征在于,所述传输电路包含输入端口、第一输出端口以及第二输出端口;The detecting circuit of claim 2, wherein the transmitting circuit comprises an input port, a first output port, and a second output port;
    所述输入端口与所述第一输出端口之间的第一传输阻抗匹配于所述预定输入阻抗。A first transmission impedance between the input port and the first output port is matched to the predetermined input impedance.
  5. 如权利要求4所述的侦测电路,其特征在于,所述输入端口与所述第二输出端口之间具有第二传输阻抗,所述第一输出端口与所述第二输出端口之间具有第三传输阻抗;The detecting circuit of claim 4, wherein the input port and the second output port have a second transmission impedance, and the first output port and the second output port have Third transmission impedance;
    所述处理电路调整所述第二传输阻抗与所述第三传输阻抗之间的 比例,以根据所述第二传输阻抗与所述第三传输阻抗之间的比例、所述第一声音信号与所述特征信号来检测所述音频播放驱动单元是否位于所述预定共振环境。The processing circuit adjusts a ratio between the second transmission impedance and the third transmission impedance to be based on a ratio between the second transmission impedance and the third transmission impedance, the first sound signal and The characteristic signal detects whether the audio playback drive unit is located in the predetermined resonance environment.
  6. 如权利要求5所述的侦测电路,其特征在于,所述第二传输阻抗是所述第三传输阻抗的二分之一。The detection circuit of claim 5 wherein said second transmission impedance is one-half of said third transmission impedance.
  7. 如权利要求2所述的侦测电路,其特征在于,所述传输电路针对所述预定输入阻抗于特定频率范围进行阻抗匹配。The detection circuit of claim 2 wherein said transmission circuit performs impedance matching for said predetermined input impedance over a particular frequency range.
  8. 如权利要求7所述的侦测电路,其特征在于,所述特定频率范围包含超声波的频率范围和可听声波的频率范围的至少其一。The detecting circuit of claim 7, wherein said specific frequency range comprises at least one of a frequency range of the ultrasonic waves and a frequency range of the audible sound waves.
  9. 如权利要求1-8任一项所述的侦测电路,其特征在于,当所述特征信号相对于所述第一声音信号的信号强度介于强度特征范围内,且所述特征信号相对于所述第一声音信号的相位变化介于相位特征范围内时,所述处理电路判断所述音频播放驱动单元位于所述预定共振环境;当所述特征信号相对于所述第一声音信号的信号强度未介于所述强度特征范围内,或所述特征信号相对于所述第一声音信号的相位变化未介于所述相位特征范围内时,所述处理电路判断所述音频播放驱动单元不位于所述预定共振环境。The detecting circuit according to any one of claims 1 to 8, wherein when the signal intensity of the characteristic signal relative to the first sound signal is within a range of intensity characteristics, and the characteristic signal is relative to When the phase change of the first sound signal is within the phase feature range, the processing circuit determines that the audio playback driving unit is located in the predetermined resonance environment; and when the characteristic signal is relative to the signal of the first sound signal When the intensity is not within the range of the intensity characteristic, or the phase change of the characteristic signal relative to the first sound signal is not within the phase feature range, the processing circuit determines that the audio playback driving unit does not Located in the predetermined resonant environment.
  10. 如权利要求1-8任一项所述的侦测电路,其特征在于,当所述特征信号相对于所述第一声音信号的信号强度介于强度特征范围内时,所述处理电路判断所述音频播放驱动单元位于所述预定共振环境;当所述特征信号相对于所述第一声音信号的信号强度未介于所述强度特征范围内时,所述处理电路判断所述音频播放驱动 单元不位于所述预定共振环境。The detecting circuit according to any one of claims 1 to 8, wherein when the signal intensity of the characteristic signal relative to the first sound signal is within a range of intensity characteristics, the processing circuit determines The audio playback driving unit is located in the predetermined resonance environment; when the signal strength of the characteristic signal relative to the first sound signal is not within the intensity characteristic range, the processing circuit determines the audio playback driving unit Not located in the predetermined resonant environment.
  11. 如权利要求1-8任一项所述的侦测电路,其特征在于,当所述特征信号相对于所述第一声音信号的相位变化介于相位特征范围内时,所述处理电路判断所述音频播放驱动单元位于所述预定共振环境;当所述特征信号相对于所述第一声音信号的相位变化未介于所述相位特征范围内时,所述处理电路判断所述音频播放驱动单元不位于所述预定共振环境。The detecting circuit according to any one of claims 1 to 8, wherein when the phase change of the characteristic signal with respect to the first sound signal is within a phase characteristic range, the processing circuit determines The audio playback driving unit is located in the predetermined resonance environment; when the phase change of the characteristic signal relative to the first sound signal is not within the phase feature range, the processing circuit determines the audio playback driving unit Not located in the predetermined resonant environment.
  12. 一种侦测方法,其特征在于,包含以下步骤:A detection method is characterized in that it comprises the following steps:
    将第一声音信号馈入音频播放驱动单元所耦接的第一传输路径,以产生第二声音信号至所述音频播放驱动单元;Feeding the first sound signal to the first transmission path coupled to the audio playback driving unit to generate a second sound signal to the audio playback driving unit;
    至少根据所述第一声音信号与所述第二声音信号,于所述音频播放驱动单元所耦接的第二传输路径产生特征信号,其中所述第二传输路径不同于所述第一传输路径;以及Generating a feature signal to the second transmission path coupled to the audio playback driving unit according to the first sound signal and the second sound signal, wherein the second transmission path is different from the first transmission path ;as well as
    至少根据所述第一声音信号与所述特征信号检测所述音频播放驱动单元是否位于预定共振环境。Detecting whether the audio playback driving unit is located in a predetermined resonance environment based on at least the first sound signal and the characteristic signal.
  13. 如权利要求12所述的方法,其特征在于,至少根据所述第一声音信号与所述第二声音信号于所述音频播放驱动单元所耦接的第二传输路径产生特征信号的步骤包含:The method of claim 12, wherein the step of generating a feature signal based on at least the first sound signal and the second sound signal coupled to the second transmission path of the audio playback drive unit comprises:
    将所述第一声音信号通过第三传输路径耦接到所述第二传输路径,以根据所述第一声音信号与所述第二声音信号于第二传输路径产生特征信号,其中所述第三传输路径不同于所述第一传输路径。Coupling the first sound signal to the second transmission path through a third transmission path to generate a characteristic signal according to the first sound signal and the second sound signal in a second transmission path, wherein the The three transmission paths are different from the first transmission path.
  14. 如权利要求13所述的方法,其特征在于,所述第一传输路径、所述第二传输路径与所述第三传输路径用来对预定输入阻抗进行阻抗匹配,所述预定输入阻抗为所述音频播放驱动单元在所述预定共振环境时的输入阻抗。The method of claim 13 wherein said first transmission path, said second transmission path and said third transmission path are used for impedance matching of a predetermined input impedance, said predetermined input impedance being The input impedance of the audio playback drive unit in the predetermined resonant environment.
  15. 如权利要求14所述的方法,其特征在于,所述第一传输路径所具有的第一传输阻抗匹配于所述预定输入阻抗。The method of claim 14 wherein said first transmission path has a first transmission impedance that matches said predetermined input impedance.
  16. 如权利要求15所述的方法,其特征在于,至少根据所述第一声音信号与所述特征信号检测所述音频播放驱动单元是否位于预定共振环境的步骤包含:The method according to claim 15, wherein the step of detecting whether the audio playback driving unit is located in a predetermined resonance environment based on at least the first sound signal and the characteristic signal comprises:
    调整所述第二传输路径所具有的第二传输阻抗与所述第三传输路径所具有的第三传输阻抗之间的比例;以及Adjusting a ratio between a second transmission impedance of the second transmission path and a third transmission impedance of the third transmission path;
    根据所述第二传输阻抗与所述第三传输阻抗之间的比例、所述第一声音信号与所述特征信号来检测所述音频播放驱动单元是否位于所述预定共振环境。Detecting whether the audio playback driving unit is located in the predetermined resonance environment according to a ratio between the second transmission impedance and the third transmission impedance, the first sound signal and the characteristic signal.
  17. 如权利要求16所述的方法,其特征在于,所述第二传输路径所具有的第二传输阻抗是所述第三传输路径所具有的第三传输阻抗的二分之一。The method of claim 16 wherein said second transmission path has a second transmission impedance that is one-half of a third transmission impedance of said third transmission path.
  18. 如权利要求14所述的方法,其特征在于,所述第一传输路径、所述第二传输路径与所述第三传输路径是于特定频率范围对所述预定输入阻抗进行阻抗匹配The method of claim 14 wherein said first transmission path, said second transmission path and said third transmission path are impedance matched to said predetermined input impedance over a particular frequency range
  19. 如权利要求18所述的方法,其特征在于,所述特定频率范围属 于超声波或可听声波的频率范围。The method of claim 18 wherein said particular frequency range is in the frequency range of an ultrasonic or audible sound wave.
  20. 如权利要求12所述的方法,其特征在于,至少根据所述第一声音信号与所述特征信号检测所述音频播放驱动单元是否位于预定共振环境的步骤包含:The method according to claim 12, wherein the step of detecting whether the audio playback driving unit is located in a predetermined resonance environment based on at least the first sound signal and the characteristic signal comprises:
    当所述特征信号相对于所述第一声音信号的信号强度介于强度特征范围内,且所述特征信号相对于所述第一声音信号的相位变化介于相位特征范围内时,判断所述音频播放驱动单元位于所述预定共振环境;以及Determining that the signal strength of the feature signal relative to the first sound signal is within a range of intensity characteristics, and a phase change of the feature signal relative to the first sound signal is within a phase feature range An audio playback drive unit is located in the predetermined resonant environment;
    当所述特征信号相对于所述第一声音信号的信号强度未介于所述强度特征范围内,或所述特征信号相对于所述第一声音信号的相位变化未介于所述相位特征范围内时,判断所述音频播放驱动单元不位于所述预定共振环境。When the signal strength of the characteristic signal relative to the first sound signal is not within the intensity characteristic range, or the phase change of the characteristic signal relative to the first sound signal is not within the phase feature range When it is inside, it is judged that the audio playback drive unit is not located in the predetermined resonance environment.
PCT/CN2018/076812 2018-02-14 2018-02-14 Detection circuit and method WO2019157698A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/CN2018/076812 WO2019157698A1 (en) 2018-02-14 2018-02-14 Detection circuit and method
CN201880000300.6A CN110383854B (en) 2018-02-14 2018-02-14 Detection circuit and method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2018/076812 WO2019157698A1 (en) 2018-02-14 2018-02-14 Detection circuit and method

Publications (1)

Publication Number Publication Date
WO2019157698A1 true WO2019157698A1 (en) 2019-08-22

Family

ID=67619058

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2018/076812 WO2019157698A1 (en) 2018-02-14 2018-02-14 Detection circuit and method

Country Status (2)

Country Link
CN (1) CN110383854B (en)
WO (1) WO2019157698A1 (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007281916A (en) * 2006-04-07 2007-10-25 Nittetsu Elex Co Ltd Earphone microphone
CN101800920A (en) * 2009-02-06 2010-08-11 索尼公司 Signal processing apparatus, signal processing method and program
CN102104388A (en) * 2009-12-16 2011-06-22 鸿富锦精密工业(深圳)有限公司 Audio play system and earphone used by same
CN104244129A (en) * 2014-09-03 2014-12-24 深圳奇沃智联科技有限公司 Contact earphones capable of being automatically switched on or off
CN105491483A (en) * 2015-11-30 2016-04-13 歌尔声学股份有限公司 Wearing state detection method and system for earphone and earphone

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012169828A (en) * 2011-02-14 2012-09-06 Sony Corp Sound signal output apparatus, speaker apparatus, sound signal output method
JP2012169839A (en) * 2011-02-14 2012-09-06 Sony Corp Sound signal output apparatus and sound signal output method
CN104901650B (en) * 2015-05-27 2017-12-15 北京工业大学 A kind of impedance-matching device and its implementation of high-power high-frequency driving source

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007281916A (en) * 2006-04-07 2007-10-25 Nittetsu Elex Co Ltd Earphone microphone
CN101800920A (en) * 2009-02-06 2010-08-11 索尼公司 Signal processing apparatus, signal processing method and program
CN102104388A (en) * 2009-12-16 2011-06-22 鸿富锦精密工业(深圳)有限公司 Audio play system and earphone used by same
CN104244129A (en) * 2014-09-03 2014-12-24 深圳奇沃智联科技有限公司 Contact earphones capable of being automatically switched on or off
CN105491483A (en) * 2015-11-30 2016-04-13 歌尔声学股份有限公司 Wearing state detection method and system for earphone and earphone

Also Published As

Publication number Publication date
CN110383854B (en) 2021-06-18
CN110383854A (en) 2019-10-25

Similar Documents

Publication Publication Date Title
EP2202998B1 (en) A device for and a method of processing audio data
US11741935B2 (en) Communication apparatus with ambient noise reduction
US10080092B2 (en) On/off head detection of personal acoustic device using an earpiece microphone
US20110144779A1 (en) Data processing for a wearable apparatus
US9648410B1 (en) Control of audio output of headphone earbuds based on the environment around the headphone earbuds
US11875771B2 (en) Audio system and signal processing method for an ear mountable playback device
US11463798B2 (en) Headphone operation during headphone insertion detection
CN104581526A (en) Sensor
WO2022017469A1 (en) Headphone call method and headphones
TWI713374B (en) Audio adjustment method and associated audio adjustment device for active noise cancellation
US20230209258A1 (en) Microphone system
US10631078B2 (en) Headset
CN100518384C (en) Passive electroacoustic apparatus and its playing method
WO2019157698A1 (en) Detection circuit and method
US20050226439A1 (en) Noise cancellation using virtually lossless sensing method
KR20240020130A (en) Electronic device and method for control audio signal based on sensor
CN117278900A (en) Howling suppression method for earphone monitoring
KR20190071890A (en) Apparatus and method for removing white noise of a acoustic apparatus

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: 18906583

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18906583

Country of ref document: EP

Kind code of ref document: A1