CN102546895B - Mobile phone and audio processing circuit thereof - Google Patents
Mobile phone and audio processing circuit thereof Download PDFInfo
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- CN102546895B CN102546895B CN201210022723.2A CN201210022723A CN102546895B CN 102546895 B CN102546895 B CN 102546895B CN 201210022723 A CN201210022723 A CN 201210022723A CN 102546895 B CN102546895 B CN 102546895B
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Abstract
The invention discloses an audio processing circuit. The audio processing circuit comprises a low-pass filter, a phase inverter, a bass speaker, a balance speaker and a first sound chamber, wherein the low-pass filter is used for carrying out low-pass filtering processing on audio signals so as to generate bass playing signals, the phase inverter is used for carrying out phase inversion processing on the bass playing signals so as to generate bass phase-inverted playing signals, the bass speaker is used for playing the bass playing signals, the balance speaker is used for playing the bass phase-inverted playing signals, and the bass speaker and the balance speaker are oppositely arranged in the first sound chamber. By using the manner, the bass speaker and the balance speaker can be oppositely arranged in the first sound chamber according to the audio processing circuit; as the bass speaker and the balance speaker are oppositely arranged in the first sound chamber and simultaneously play the playing signals which are in inverted phases relative to each other, the bass speaker can do fully-free piston motion according to the sizes of the signals, and the bass performance is optimized.
Description
Technical field
The present invention relates to communication field, particularly relate to a kind of mobile phone and audio frequency processing circuit thereof.
Background technology
Along with the development of mobile terminal, mobile terminal is concentrated increasing function.Wherein, sound is play is a wherein very important function.But the sound on Nowadays mobile terminals is play the main monophony that adopts and is play, and can not meet the requirement of the growing high-quality hearing enjoying of people.
Prior art provides a kind of stereo surround audio intensifier circuit, by design two stage filter circuit, first order high-pass filtering filter out low frequency disturbs, second level filter circuit to left and right acoustic channels difference signal carry out filtering process, then the enterprising line output of the one-level that is added to respectively filtered left and right acoustic channels main signal, thus realize stereophonic effect.
But when the low-frequency component of audio signal is all exported by loudspeaker by this method, because the Amplitude Comparison of loudspeaker is large, cause the air pressure in sound chamber larger, the vibration of loudspeaker is suppressed, and causes bass performance poor, affects the experience of user.
Summary of the invention
The technical problem that the present invention mainly solves is to provide a kind of mobile phone and audio frequency processing circuit thereof, bass horn can be made can to do the motion of sufficient free piston according to the size of signal, thus optimize bass performance.
The present invention is the technical scheme that technical solution problem adopts: provide a kind of audio frequency processing circuit, comprising: low pass filter, carry out low-pass filtering treatment to audio signal, produces bass play signal; Phase inverter, carries out paraphase process to described bass play signal, produces bass paraphase play signal; Bass horn, plays described bass play signal; Balance loudspeaker, play described bass paraphase play signal; First sound chamber, described bass horn and described balance loudspeaker are relatively arranged in described first sound chamber.
Wherein, described audio frequency processing circuit comprises high pass filter and loudspeaker further, and described high pass filter carries out high-pass filtering process to described audio signal, produces high pitch play signal, and is sent in described loudspeaker and plays.
Wherein, described audio frequency processing circuit comprises the second sound chamber further, and described loudspeaker is arranged in described second sound chamber.
Wherein, the technical parameter of described bass horn and described balance loudspeaker is completely the same.
Wherein, described audio signal is left channel audio signal.
Wherein, described audio signal is right channel audio signal.
Wherein, described audio frequency processing circuit comprises audio frequency amplifier and signal source further, and described signal source exports original audio signal, and described audio frequency amplifier carries out amplification process, to produce described audio signal to described original audio signal.
The present invention is the technical scheme that technical solution problem adopts: provide a kind of mobile phone, mobile phone comprises above-mentioned audio frequency processing circuit.
Wherein, signal source is the base band signal processing chip of mobile phone.
Wherein, balance loudspeaker to arrange towards interior of mobile phone.
The invention has the beneficial effects as follows: the situation being different from prior art, the present invention carries out paraphase process to produce bass paraphase play signal by arranging phase inverter to bass play signal, and bass horn broadcasting bass play signal is set, balance loudspeaker are set and play bass paraphase play signal, and bass horn and balance loudspeaker are relatively arranged in the first sound chamber, due in the first sound chamber, bass horn and balance loudspeaker are oppositely arranged, and play the play signal of mutual paraphase simultaneously, make bass horn can do the motion of sufficient free piston according to the size of signal, thus optimize bass performance.
Accompanying drawing explanation
Fig. 1 is the electrical block diagram of audio frequency processing circuit according to a first embodiment of the present invention;
Fig. 2 is the physical circuit figure of audio frequency processing circuit according to a first embodiment of the present invention;
Fig. 3 is the electrical block diagram of audio frequency processing circuit according to a second embodiment of the present invention;
Fig. 4 is the physical circuit figure of audio frequency processing circuit according to a second embodiment of the present invention;
Fig. 5 is the electrical block diagram of mobile phone according to a third embodiment of the present invention.
Embodiment
Below in conjunction with drawings and Examples, the present invention is described in detail.
First Fig. 1 is referred to, Fig. 1 is the electrical block diagram of audio frequency processing circuit according to a first embodiment of the present invention, as shown in Figure 1, in the first embodiment of the invention, audio frequency processing circuit of the present invention comprises low pass filter 101, phase inverter 102, bass horn 103, balance loudspeaker 104 and the first sound chamber 105.
Wherein, low pass filter 101 pairs of audio signals 100 carry out low-pass filtering treatment, wherein can preferably intercept the frequency being less than 300 hertz, produce bass play signal, phase inverter 102 pairs of bass play signal carry out paraphase process, and produce bass paraphase play signal, this bass play signal play by bass horn 103, this bass paraphase play signal play by balance loudspeaker 104, and bass horn 103 and balance loudspeaker 104 are relatively arranged in the first sound chamber 105.
Filter out the high-frequency signal in audio signal 100 by low pass filter 101, produce bass play signal and be directly inputted to bass horn 103 and export.And this bass play signal inputs to phase inverter 102 carries out paraphase process simultaneously, produce corresponding bass paraphase play signal, the phase place of this bass paraphase play signal lags behind bass play signal 180 degree, and this bass paraphase play signal input to balance loudspeaker 104 export.
Wherein, it is completely the same that bass horn 103 and balance loudspeaker 104 can be set to technical parameter, make the bass play signal inputing to bass horn 103 identical with inputing to the bass paraphase play signal amplitude balancing loudspeaker 104, phase 180 degree, and because sound chamber (being specifically relatively arranged in described first sound chamber 105) shared by bass horn 103 and balance loudspeaker 104, pressure in first sound chamber 105 is almost remained unchanged, thus makes bass horn 103 almost can completely along with the size of bass play signal does the motion of sufficient free piston.Thus, by above setting, the output performance of bass horn 103 is greatly improved.
It should be noted that, the technical parameter of bass horn 103 and balance loudspeaker 104 also can be set to difference, as amplitude is set to difference, for example when bass horn 103 amplitude is comparatively greater than balance loudspeaker 104 amplitude, first sound chamber 105 can be subject to the reaction force of sound chamber inner air, thus the amplitude relative theory value of bass horn 103 is obviously weakened, now, technique effect when though it can not reach completely the same with technical parameter, but for the situation of phase inverter 102 and balance loudspeaker 104 is not set, preferably technique effect can also be reached.
Refer to Fig. 2 below, wherein Fig. 2 is the physical circuit figure of audio frequency processing circuit according to a first embodiment of the present invention, as shown in Figure 2, the electric circuit diagram design of audio frequency processing circuit of the present invention as shown in Figure 2, low pass filter 101 can realize with inductance or magnetic bead B1, audio signal 100 is through inductance or magnetic bead B1, inductance or magnetic bead B1 filter the HFS in audio signal 100, play the effect of low-pass filtering, specifically can select the parameter of inductance or magnetic bead B1, its cut-off frequency is made to be similar to f=1/ (2* π * R3*C2), thus by the frequency of audio signal 100 lower than f=1/ (2* π * R3*C2) Partial filtration out, to produce bass play signal, this bass play signal Direct driver bass horn 103 (its internal resistance is generally 8 ohm) can be utilized.
This bass play signal is input to phase inverter 102 simultaneously and carries out paraphase process, wherein, in this phase inverter 102, the both positive and negative polarity of amplifier U2 is connected respectively to voltage VDD and-VDD, both positive and negative polarity voltage amplitude is equal, polarity is contrary, the positive pole input grounding of amplifier U2, such bias current is 0 volt, thus guarantees that the positive negative part of amplifier U2 to input signal can amplify.And the resistance of resistance R5 with R4 is identical, thus guarantee that amplifier U2 input/output signal amplitude is consistent, polarity contrary, play the effect of paraphase.After the bass play signal that low pass filter exports is carried out paraphase process by phase inverter 102, obtain the bass paraphase play signal of phase 180, then utilize this bass paraphase play signal to drive the balance loudspeaker 104 consistent with bass horn 103 parameter.
Refer to Fig. 3, Fig. 3 is the electrical block diagram of audio frequency processing circuit according to a second embodiment of the present invention, as shown in Figure 3, second embodiment of the invention is provided with audio frequency amplifier 109, signal source Vin, high pass filter 106, loudspeaker 107 and the second sound chamber 108 further on the basis of the first embodiment.
Wherein, signal source Vin exports original audio signal, audio frequency amplifier 109 pairs of original audio signals carry out amplification process, to produce audio signal 100, high pass filter 106 pairs of audio signals 100 carry out high-pass filtering process, wherein can preferably intercept the frequency being greater than 300 hertz, to produce high pitch play signal, loudspeaker 107 plays high pitch play signal, and loudspeaker 107 is arranged in the second sound chamber 108.Wherein, first sound chamber 105 and the second sound chamber 108 are independently sound chamber separately, thus ensure that high pitch play signal and bass play signal do not interfere with each other, and, the volume in the first sound chamber 105 is greater than the volume in the second sound chamber 108, to ensure that bass play signal and high pitch play signal all obtain good bass, high pitch performance.
And referring to Fig. 4, Fig. 4 is the physical circuit figure of audio frequency processing circuit according to a second embodiment of the present invention, and as shown in Figure 4, wherein Fig. 4 has set up audio frequency amplifier 109, high pass filter 106 and loudspeaker 107 on the basis of circuit diagram shown in Fig. 2.
First the original audio signal exported by audio signal source Vin amplifies through audio frequency amplifier 109, the front end of audio frequency amplifier 109 forms high pass filter by resistance R1 and electric capacity C1, for being removed by the direct current biasing in original audio signal, its cut-off frequency is f=1/ (2* π * R1*C1).Original audio signal is by AC signal part remaining after high pass filter, the positive pole input delivering to amplifier U1 is amplified, the both positive and negative polarity of amplifier U1 is connected respectively to voltage VDD and-VDD, both positive and negative polarity voltage amplitude is equal, polarity is contrary, the positive pole input grounding of amplifier U1, such bias current is 0 volt, thus guarantees that the positive negative part of amplifier U1 to input signal can amplify and the audio signal 100 exported does not contain DC bias signal.The multiplication factor of amplifier U1 is determined by resistance R1 and R2, and namely audio signal 100 is approximately equal to: the AC portion * R2/R1 in original audio signal.
The high pass filter 106 that the audio signal 100 that amplifier U1 exports forms through electric capacity C2 and resistance R3, the cut-off frequency of this high pass filter 106 is f=1/ (2* π * R3*C2), amplifier U1 export audio signal 100 frequency higher than f=1/ (2* π * R3*C2) partly (i.e. high pitch play signal) can pass through, this high pitch play signal drive loudspeaker 107 (internal resistance is 8 ohm) work.
The audio signal 100 that amplifier U1 exports is through inductance or magnetic bead B1, inductance or magnetic bead B1 filter HFS, play the effect of low pass filter, by selecting the parameter of inductance or magnetic bead B1, make the cut-off frequency of low pass filter 101 be similar to f=1/ (2* π * R3*C2), thus by amplifier U1 export audio signal 100 frequency lower than f=1/ (2* π * R3*C2) partly (i.e. bass play signal) be filtered out.This bass play signal can Direct driver bass horn 103 (internal resistance is 8 ohm); The bass play signal simultaneously exported by low pass filter 101 can be input to phase inverter 102 and carry out paraphase process.The both positive and negative polarity of the amplifier U2 in phase inverter 102 is connected respectively to voltage VDD and-VDD, both positive and negative polarity voltage amplitude is equal, polarity is contrary, the positive pole input grounding of amplifier U2, such bias current is 0 volt, thus guarantees that the positive negative part of amplifier U2 to input signal can amplify.Resistance R5 is identical with R4 value, thus guarantees that amplifier U2 input/output signal amplitude is consistent, polarity contrary, plays the effect of paraphase.Obtain the low frequency signal (i.e. bass paraphase play signal) of phase 180 after the bass play signal paraphase that low pass filter 101 exports by phase inverter 102, then utilize bass paraphase play signal to drive the balance loudspeaker 104 consistent with bass horn 103 parameter.By arranging the parameter of high pass filter 106 and low pass filter 101, following effect can be realized.
In treble portion (signal frequency of audio signal 100 is far above the part of f=1/ (2* π * R3*C2)), high pass filter 106 pairs of audio signals 100 carry out high-pass filtering process, due to the buffer action of low pass filter 101, treble portion is not almost had to export to bass horn 103 and balance loudspeaker 104, so treble portion is almost exported by loudspeaker 107 completely.
In frequency close to cut-off frequency part (signal frequency of audio signal 100 is close to the part of f=1/ (2* π * R3*C2)), because audio signal is simultaneously by high pass filter 106 and low pass filter 101, its amplitude all has and necessarily weakens (when the signal frequency of audio signal 100 is higher than f=1/ (2* π * R3*C2), more by the bass play signal amplitude fading after low pass filter 101, when in audio signal 100, signal frequency is lower than f=1/ (2* π * R3*C2), more by the high pitch play signal amplitude fading after high pass filter 106).Now, loudspeaker 107, bass horn 103, balance loudspeaker 104 work simultaneously, can prevent when the signal frequency of audio signal 100 is higher than f=1/ (2* π * R3*C2), high pass filter 106 ends it at once completely and exports, loudspeaker 107 is caused not export thus cause when audio signal 100 frequency fluctuates near cut-off frequency f=1/ (2* π * R3*C2), owing to having output during loudspeaker 107, time and do not export, cause user's sense of hearing significantly uncomfortable, similarly, also like this for bass horn 103, so in the present embodiment, by changing the signal amplitude of loudspeaker 107 and bass horn 103 smoothly, effectively improve audio signal 100 when changing, the comfort level of user's sense of hearing.
At bass part (audio signal 100 frequency is far below f=1/ (2* π * R3*C2)), due to the buffer action of high pass filter 106, audio signal 100 is not almost had to export to loudspeaker 107, and due to bass horn 103 and the effect balancing loudspeaker 104, air pressure inside first sound chamber 105 remains unchanged when bass horn 103 works, bass horn 103 can vibrate freely along with the amplitude of bass play signal, and order is improved to bass performance.
In addition, at direct current component (direct current biasing, sound source frequency 100 is far below f=1/ (2* π * R1*C1), in design, f=1/ (2* π * R1*C1) is far below f=1/ (2* π * R3*C2), f=1/ (2* π * R1*C1) design at 30 hertz to 50 hertz) due to the input buffer action of audio frequency amplifier 109, so it does not affect the output of loudspeaker, from the life-span extending loudspeaker.
It should be noted that, in the first and second embodiments of the present invention, above-mentioned audio signal 100 can be left channel audio signal or right channel audio signal, and the present invention is not construed as limiting this.
Refer to Fig. 5, Fig. 5 is the electrical block diagram of mobile phone according to a third embodiment of the present invention, as shown in Figure 5, in second embodiment of the invention, further disclose a kind of mobile phone, it comprises the audio frequency processing circuit described in the second embodiment, and, owing to considering the difference of left and right acoustic channels, therefore, in the second embodiment of the present invention, be provided with the audio frequency processing circuit described in two the second embodiments, the difference of two audio frequency processing circuits is that input signal is different, specifically be respectively left channel audio signal and right channel audio signal, and, signal source described in second embodiment specifically can be the base band signal processing chip 200 in mobile phone, wherein, base band signal processing chip 200 has port Vin and port Vin ', its middle port Vin exports original left channel audio signal, port Vin ' exports original right channel audio signal.Wherein, left and right sound channels audio signal is set simultaneously, good played in stereo effect can be realized.
In the present embodiment, balance loudspeaker 104, 104 ' can be arranged towards interior of mobile phone, make to balance loudspeaker 104, the output of 104 ' is towards interior of mobile phone, owing to being subject to the buffer action of phone housing, by balance loudspeaker 104, 104 ' the sound the exported part be leaked to outside mobile phone can obtain and weaken greatly (decay having decades of times at least), meanwhile, bass horn 103, 103 ' also in work, that is loudspeaker 104 are balanced, 104 ' exports the sound that is leaked to outside mobile phone than bass horn 103, 103 ' the sound exported wants little decades of times, thus it is negligible, therefore, this design greatly improves the bass performance of mobile phone.
And, the base band signal processing chip 200 of mobile phone is utilized to export left channel audio signal and right channel audio signal as signal source, specifically, the Audio output port on base band signal processing chip 200 can be utilized to export left channel audio signal and right channel audio signal.
Therefore, the present invention carries out paraphase process to produce bass paraphase play signal by arranging phase inverter to bass play signal, and bass horn broadcasting bass play signal is set, balance loudspeaker are set and play bass paraphase play signal, and bass horn and balance loudspeaker are relatively arranged in the first sound chamber, due in the first sound chamber, bass horn and balance loudspeaker are oppositely arranged, and play the play signal of mutual paraphase simultaneously, make bass horn can do the motion of sufficient free piston according to the size of signal, thus optimize bass performance.
The foregoing is only embodiments of the invention; not thereby the scope of the claims of the present invention is limited; every utilize specification of the present invention and accompanying drawing content to do equivalent structure or equivalent flow process conversion; or be directly or indirectly used in other relevant technical fields, be all in like manner included in scope of patent protection of the present invention.
Claims (9)
1. an audio frequency processing circuit, is characterized in that, comprising:
Low pass filter, carries out low-pass filtering treatment to audio signal, produces bass play signal;
Phase inverter, carries out paraphase process to described bass play signal, produces bass paraphase play signal;
Bass horn, plays described bass play signal;
Balance loudspeaker, play described bass paraphase play signal;
First sound chamber, described bass horn and described balance loudspeaker are relatively arranged in described first sound chamber, and the technical parameter of described bass horn and described balance loudspeaker is completely the same.
2. circuit according to claim 1, it is characterized in that, described audio frequency processing circuit comprises high pass filter and loudspeaker further, and described high pass filter carries out high-pass filtering process to described audio signal, produce high pitch play signal, and be sent in described loudspeaker and play.
3. circuit according to claim 2, is characterized in that, described audio frequency processing circuit comprises the second sound chamber further, and described loudspeaker is arranged in described second sound chamber.
4. circuit according to claim 1, is characterized in that, described audio signal is left channel audio signal.
5. circuit according to claim 1, is characterized in that, described audio signal is right channel audio signal.
6. circuit according to claim 1, it is characterized in that, described audio frequency processing circuit comprises audio frequency amplifier and signal source further, and described signal source exports original audio signal, described audio frequency amplifier carries out amplification process, to produce described audio signal to described original audio signal.
7. a mobile phone, is characterized in that, described mobile phone comprises audio frequency processing circuit according to claim 6.
8. mobile phone according to claim 7, is characterized in that, described signal source is the base band signal processing chip of described mobile phone.
9. mobile phone according to claim 7, is characterized in that, described balance loudspeaker are arranged towards described interior of mobile phone.
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| CN201210022723.2A CN102546895B (en) | 2012-02-01 | 2012-02-01 | Mobile phone and audio processing circuit thereof |
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| CN201210022723.2A CN102546895B (en) | 2012-02-01 | 2012-02-01 | Mobile phone and audio processing circuit thereof |
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| CN102546895A CN102546895A (en) | 2012-07-04 |
| CN102546895B true CN102546895B (en) | 2015-05-13 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US9668081B1 (en) * | 2016-03-23 | 2017-05-30 | Htc Corporation | Frequency response compensation method, electronic device, and computer readable medium using the same |
| CN117762262A (en) * | 2022-09-23 | 2024-03-26 | 荣耀终端有限公司 | Signal transmission method and related equipment |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1169092A (en) * | 1996-04-24 | 1997-12-31 | 松下电器产业株式会社 | Loud-speaker system |
| CN1953618A (en) * | 2005-10-20 | 2007-04-25 | 雅马哈株式会社 | Speaker driving apparatus |
| CN101427589A (en) * | 2006-04-19 | 2009-05-06 | 环绕声实验股份公司 | Loudspeaker device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3531312B2 (en) * | 1995-09-20 | 2004-05-31 | 松下電器産業株式会社 | Audio reproduction circuit for television receiver |
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2012
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1169092A (en) * | 1996-04-24 | 1997-12-31 | 松下电器产业株式会社 | Loud-speaker system |
| CN1953618A (en) * | 2005-10-20 | 2007-04-25 | 雅马哈株式会社 | Speaker driving apparatus |
| CN101427589A (en) * | 2006-04-19 | 2009-05-06 | 环绕声实验股份公司 | Loudspeaker device |
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