CN101998215A - Human body sound transmission apparatus and method for minimizing signal loss - Google Patents
Human body sound transmission apparatus and method for minimizing signal loss Download PDFInfo
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- CN101998215A CN101998215A CN2010102473514A CN201010247351A CN101998215A CN 101998215 A CN101998215 A CN 101998215A CN 2010102473514 A CN2010102473514 A CN 2010102473514A CN 201010247351 A CN201010247351 A CN 201010247351A CN 101998215 A CN101998215 A CN 101998215A
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- signal
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- audio signal
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- 238000000034 method Methods 0.000 title claims abstract description 19
- 230000005540 biological transmission Effects 0.000 title abstract description 7
- 230000005236 sound signal Effects 0.000 claims abstract description 103
- 230000008054 signal transmission Effects 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 2
- 230000008034 disappearance Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
- H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
- H04R1/323—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only for loudspeakers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
- B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
- B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
- B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
- B06B1/0207—Driving circuits
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/02—Amplitude-modulated carrier systems, e.g. using on-off keying; Single sideband or vestigial sideband modulation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R2217/00—Details of magnetostrictive, piezoelectric, or electrostrictive transducers covered by H04R15/00 or H04R17/00 but not provided for in any of their subgroups
- H04R2217/03—Parametric transducers where sound is generated or captured by the acoustic demodulation of amplitude modulated ultrasonic waves
Abstract
A human body sound transmission apparatus and method for minimizing a signal loss are disclosed. The human body sound transmission apparatus includes: an audio signal transmission unit modulating an audio signal desired to be transmitted, and transmitting the modulated audio signal to the vicinity of a user's ear through the human body (i.e., a user's body); and a carrier wave signal transmission unit transmitting a carrier wave signal for demodulating the modulated audio signal to the vicinity of the user's ear through the air.
Description
Cross reference for related application
The application requires the priority of the korean patent application submitted to Korea S Department of Intellectual Property on August 6th, 2009 and on February 1st, 2010 10-2009-0072395 number and 10-2010-0008995 number, by reference it openly is herein incorporated.
Technical field
The present invention relates to a kind of be used to make minimized body sounds transfer equipment of loss of signal and method, and more specifically, relate to a kind of following technology, described technology transmits audio signal after the modulation by human body, and transmit the carrier signal that is used for this audio signal is carried out demodulation by air, thereby the loss in this audio signal that causes owing to the non-linear phenomena that takes place in the human body parts except ear is minimized, thereby be increased near the amplitude of the audio signal that generates the ear, and improve sound quality.
Background technology
In the sound transfer system of the correlation technique such as MP3 player, portable radio etc., conveyer transmits the audio signal that expectation transmits by fixed line, perhaps this audio signal is modulated and wirelessly transmit it, and near the receiving system such as the earphone etc. that is positioned at the user's ear receives from the signal of conveyer transmission, perhaps receive also and then it is carried out demodulation, thereby allow the user to hear sound.Yet the sound transfer system of correlation technique has following problem, and promptly it must comprise receiving system necessarily, and and if only if receiving system when contacting with user's health, the user just can hear sound, thereby causes user's inconvenience.
In order to make great efforts to improve user's facility of sound transfer system, a kind of body sounds tranmission techniques that is used for coming by human body transmit audio signals has been proposed.
According to the body sounds tranmission techniques that is proposed, the audio signal that expectation transmits is carried out amplitude modulation(PAM), thereby be converted into the signal of about 20kHz or higher supersonic range, and the audio signal after will modulating be used for this modulated carrier signal and make up, perhaps be converted into independent ultrasonic signal, and be applied to human body then.
The proportional linear operation of amplitude that human body (that is user) is carried out nonlinear operation and imported with signal about the ultrasonic signal that is applied.Nonlinear operation about two or more signals can be modeled as the product of two signals.That is, the audio signal that transmits when expectation is that the amplitude and the frequency of m (t) and carrier signal are respectively A
cAnd f
cThe time, can represent to pass through this carrier signal and the audio signal of amplitude modulation(PAM) by following equation 1 and equation 2:
[equation 1]
A
cm(t)coS(2πf
ct)
[equation 2]
A
ccoS(2πf
ct)
When two signals representing by equation 1 and equation 2 are converted into ultrasonic signal and are applied to the user then, come described two ultrasonic signals are carried out mixing according to user's nonlinear operation, health by the user transmits simultaneously, to generate the signal of represent by the equation 3 shown in following, it can launch to be represented by the equation 4 shown in following by the use sine formula then.
[equation 3]
A
cm(t)coS(2πf
ct)×A
ccoS(2πf
ct)
[equation 4]
In equation 4, first is the signal of the supersonic range that can not hear of user, and the signal of second sound wave section that to be the user can hear.Thereby aforementioned body sounds tranmission techniques makes the user can hear the audio signal that is transmitted, and needn't use receiving system.
Yet this body sounds tranmission techniques has following problem.That is, when the audio signal after transmitting this modulation and this carrier signal, cause all body parts of the user that passes from this signal owing to nonlinear operation and near user's ear, generate audio signal by human body.The audio signal that generates from other parts of the human body except user's ear disappearances that become caused the interior lossy of audio signal.Thereby, very little near the amplitude of the audio signal that generates the user's ear, and its sound quality is not very good.
Summary of the invention
An aspect of of the present present invention provides a kind of be used to make minimized body sounds transfer equipment of loss of signal and method, it can transmit audio signal after the modulation by human body, and transmit the carrier signal that is used for this audio signal is carried out demodulation by air, so that the loss in the audio signal that causes owing to the non-linear phenomena that takes place in the human body parts except ear minimizes, thereby be increased near the amplitude of this audio signal that generates the ear, and improve sound quality.
According to an aspect of the present invention, a kind of body sounds transfer equipment is provided, has comprised: the audio signal delivery unit is used for the audio signal that expectation transmits is modulated, and come near the audio signal that transmits user's the ear after modulating by human body (that is user's health); And the carrier signal delivery unit, be used for coming to transmitting the carrier signal that is used for the audio signal after this modulation is carried out demodulation near user's the ear by air.
Described audio signal delivery unit can comprise: audio signal generator is used to generate the audio signal that expectation transmits; Amplitude modulator is used for by using this carrier signal to come the amplitude of the audio signal that generated is modulated; And first ultrasonic transducer, be used for the audio signal behind the amplitude modulation(PAM) is converted to ultrasonic signal, and the ultrasonic signal of being changed be applied to user's health.
Described amplitude modulator can be carried out amplitude modulation(PAM) by using from the carrier signal of this carrier signal delivery unit reception, perhaps described audio signal delivery unit can comprise the carrier signal generator that is used to generate carrier signal, and in the case, described amplitude modulator can be carried out amplitude modulation(PAM) by using the carrier signal that is generated by this carrier signal generator.
Described first ultrasonic transducer can contact with the user.
Described carrier signal delivery unit can comprise: carrier signal generator is used to generate carrier signal; And second ultrasonic transducer, the carrier signal that is used for being generated is converted to ultrasonic signal, and the ultrasonic signal of being changed is sent in the air, and can comprise the secondary signal amplifier, this secondary signal amplifier is used for the carrier signal that is generated by carrier signal generator is amplified, and provides the carrier signal of being amplified to second ultrasonic transducer.
In the case, second ultrasonic transducer sensing air can be installed as, perhaps the directional ultrasonic transducer can be implemented these as.
According to a further aspect in the invention, provide a kind of minimized body sounds transfer approach of loss of signal that is used to make, having comprised: generated audio signal and carrier signal that expectation transmits; Come the amplitude of this audio signal is modulated by using this carrier signal; Audio signal behind this amplitude modulation(PAM) and this carrier signal are converted to ultrasonic signal; And by near the next audio signal that has been converted to ultrasonic signal that user's ear, transmits of user's health, and by near the next carrier signal that has been converted to ultrasonic signal that user's ear, transmits of air.This method can also comprise: after carrying out this amplitude modulation(PAM), respectively the audio signal behind this amplitude modulation(PAM) and this carrier signal are amplified.
Can be so that be converted to ultrasonic signal and be sent near near the user's ear carrier signal incides user user's ear health by air then, and in the case, this method can also comprise: near user's ear, come to being converted to ultrasonic signal and the health by the user and carry out mixing respectively then, to generate audio signal according to the nonlinear operation of user's body by this audio signal and this carrier signal that air is sent near the user's ear.
Description of drawings
The following detailed description of carrying out in conjunction with the drawings will be expressly understood top and others, feature and other advantages of the present invention more, wherein:
Fig. 1 is the concept map that is used to make minimized body sounds transfer equipment of loss of signal and method in order to explanation example embodiment according to the present invention; And
Fig. 2 is the schematic block diagram of the body sounds transfer equipment of the example embodiment according to the present invention.
Embodiment
Now, will come with reference to the accompanying drawings example embodiment of the present invention is described in detail.Yet the present invention can implement according to a lot of different forms, and should not be construed as limited to and propose embodiment here.On the contrary, provide these embodiment, make that the disclosure will be thorough and complete, and will fully pass on scope of the present invention to those skilled in the art.In described figure, can be for clear and exaggerative shape and size, and will use identical Reference numeral to specify identical or similar elements all the time.
To understand, when element being called when " linking to each other " with another element, it can directly link to each other with this another element, perhaps also can have element between two parties.On the contrary, when element being called when this another element " directly links to each other ", there is not element between two parties.In addition, unless describe on the contrary clearly, otherwise word " comprises (comprise) " and will be understood that to hint such as the distortion of " comprising (comprises) " or " comprising (comprising) " and comprise the element of being stated but do not get rid of any other element.
Fig. 1 is the concept map that is used to make minimized body sounds transfer equipment of loss of signal and method in order to explanation example embodiment according to the present invention.
In example embodiment of the present invention, for make owing to non-linear phenomena cause at the human body parts except user's ear (promptly, the loss of the audio signal that occurs user's health) minimizes, and body sounds transfer equipment 100 transmits audio signal and carrier signal after the modulation by independent standalone media respectively.
At length, near the audio signal of the health 10 of body sounds transfer equipment 100 by the user after transmitting modulation user's the ear, and transmit carrier signal so that make it near user's ear, incide user's health 10 by air.
Correspondingly, near user's ear, meet by audio signal and this carrier signal after this modulation of body sounds transfer equipment 100 transmission, generate audio signal with nonlinear operation, allow the user to hear this audio signal (that is Dui Ying sound) according to user's body.
Fig. 2 is the schematic block diagram of the body sounds transfer equipment of the example embodiment according to the present invention.Body sounds transfer equipment 100 comprises: audio signal delivery unit 110 is used for the audio signal after health by the user transmits modulation; And carrier signal delivery unit 120, be used for transmitting carrier signal by air.
Audio signal delivery unit 110 is configured to comprise audio signal generator 111, amplitude modulator 112, first signal amplifier 113 and first ultrasonic transducer 114.
Audio signal generator 111 generates the audio signal that expectation transmits.
The audio signal that amplitude modulator 112 received audio signal generators 111 have generated, and the amplitude of the audio signal that received modulated.In the case, amplitude modulator 112 comes this audio signal is carried out amplitude modulation(PAM) by the carrier signal of using carrier signal generator 121 to generate.
In Fig. 2, carrier signal generator 121 is illustrated as and makes it be included in the carrier signal delivery unit 120, but the invention is not restricted to this, and can realize the present invention, make carrier signal generator be included in the audio signal delivery unit 110, and carrier signal delivery unit 120 receives the carrier signal that is generated by audio signal delivery unit 110, and transmits the carrier signal that is received.
113 pairs of amplitude modulators of first signal amplifier, 112 modulated audio signals are amplified, and make this audio signal have the health of enough permissions by the user and send it near the user's ear amplitude.
Audio signal is converted to ultrasonic signal after the modulation that first ultrasonic transducer 114 has amplified first signal amplifier 113, and the ultrasonic signal of being changed is applied to user's health.For this reason, preferably, first ultrasonic transducer 114 contacts with user's health.
Health by the user comes audio signal after near the audio signal delivery unit 110 that transmits configuration as mentioned above user's the ear has been applied to the modulation of user's body.
Carrier signal delivery unit 120 is configured to comprise carrier signal generator 121, secondary signal amplifier 122 and second ultrasonic transducer 123 therebetween.
The carrier signal that 122 pairs of carrier signal generators 121 of secondary signal amplifier have generated is amplified.
Second ultrasonic transducer 123 is converted to ultrasonic signal with the carrier signal that secondary signal amplifier 122 has amplified, and transmits the ultrasonic signal of being changed by air near user's ear.For this reason, preferably, in body sounds transfer equipment 100, second ultrasonic transducer 123 is installed as the sensing air.
In addition, the ultrasonic signal that transmits in order to prevent dissipates in air, and in order to transmit ultrasonic signal, makes it is focused near user's the ear, preferably uses the directional ultrasonic transducer as second ultrasonic transducer 123.
The signal that near the carrier signal delivery unit 120 that transmission is disposed as mentioned above user's ear has transmitted in air, and make it near user's ear, incide user's health then.
Now, the method that is used for transmitting by the body sounds transfer equipment that uses the example embodiment according to the present invention body sounds will be described with reference to Figure 2.
At first, audio signal generator 111 generates the audio signal that expectation transmits, and carrier signal generator 121 generations will be used for the amplitude of this audio signal is carried out modulated carrier signal.
Next, the carrier signal that audio signal that amplitude modulator 112 received audio signal generators 111 have generated and carrier signal generator 121 have generated, and by using this carrier signal to come this audio signal is carried out amplitude modulation(PAM).
Thereafter, first and second signal amplifiers 113 and 122 amplify the audio signal after this modulation and this carrier signal respectively, make them have enough the health by the user or are sent near the user's ear size by air.
After this, first ultrasonic transducer 114 is converted to ultrasonic signal with audio signal after the modulation of being amplified, and the health by the user transmits the ultrasonic signal of being changed near user's ear, and second ultrasonic transducer 123 is converted to ultrasonic signal with the carrier signal of being amplified, and transmits the ultrasonic signal of being changed by air near user's ear.Then, make and to be sent near near the user's ear ultrasonic signal incides user user's ear health by air.
Come near user's the ear audio signal and the carrier signal that are sent to by user's health with by air as described above near the user's ear are being carried out mixing according to the nonlinear operation of user's body, with the generation audio signal, and the user can hear the audio signal that is generated.
As illustrated in top, the embodiment of demonstration according to the present invention, because the health by the user transmits the audio signal after the modulation, and transmit by air and will be used for audio signal is carried out modulated carrier signal, so the loss of the audio signal that causes owing to non-linear phenomena, occur in the part of the user's body except user's ear is minimized.Therefore, can be increased near the amplitude of the audio signal that generates the user's ear, and can improve its sound quality.
Although illustrated and described the present invention in conjunction with example embodiment, it is apparent to those skilled in the art that and to make modifications and variations, and do not break away from the spirit and scope of the present invention that are defined by the following claims.
Claims (18)
1. body sounds transfer equipment comprises:
The audio signal delivery unit is used for the audio signal that expectation transmits is modulated, and comes near the audio signal that transmits user's the ear after modulating by user's health; And
The carrier signal delivery unit is used for coming to transmitting the carrier signal that will be used for the audio signal after the described modulation is carried out demodulation near user's the ear by air.
2. according to the equipment of claim 1, wherein said audio signal delivery unit comprises:
Audio signal generator is used to generate the audio signal that expectation transmits;
Amplitude modulator is used for by using this carrier signal to come the amplitude of the audio signal that generated is modulated; And
First ultrasonic transducer is used for the audio signal behind the amplitude modulation(PAM) is converted to ultrasonic signal, and the ultrasonic signal of being changed is applied to user's health.
3. according to the equipment of claim 2, wherein said amplitude modulator is carried out amplitude modulation(PAM) by using from the carrier signal of carrier signal delivery unit reception.
4. according to the equipment of claim 2, wherein said audio signal delivery unit comprises the carrier signal generator that is used to generate carrier signal, and described amplitude modulator is carried out amplitude modulation(PAM) by using the carrier signal that is generated by this carrier signal generator.
5. according to the equipment of claim 2, wherein said first ultrasonic transducer contacts with user's health.
6. according to the equipment of claim 2, wherein said audio signal delivery unit also comprises first signal amplifier, this first signal amplifier is used for the audio signal of modulating its amplitude by amplitude modulator is amplified, and provides the audio signal of being amplified to described first ultrasonic transducer.
7. according to the equipment of claim 1, wherein said carrier signal delivery unit comprises:
Carrier signal generator is used to generate carrier signal; And
Second ultrasonic transducer, the carrier signal that is used for being generated is converted to ultrasonic signal, and the ultrasonic signal of being changed is sent in the air.
8. according to the equipment of claim 7, wherein described second ultrasonic transducer is installed as the sensing air.
9. according to the equipment of claim 7, wherein described second ultrasonic transducer is embodied as the directional ultrasonic transducer.
10. according to the equipment of claim 7, wherein said carrier signal delivery unit also comprises the secondary signal amplifier, this secondary signal amplifier is used for the carrier signal that this carrier signal generator has generated is amplified, and the carrier signal that provides this to amplify to this second ultrasonic transducer.
11. equipment according to claim 4, wherein said carrier signal delivery unit comprises second ultrasonic transducer, this second ultrasonic transducer is used for the carrier signal that this carrier signal generator has generated is converted to ultrasonic signal, and the ultrasonic signal of being changed is sent in the air.
12. according to the equipment of claim 11, wherein said second ultrasonic transducer is installed to be the sensing air.
13., wherein described second ultrasonic transducer is embodied as the directional ultrasonic transducer according to the equipment of claim 11.
14. equipment according to claim 11, wherein said carrier signal delivery unit also comprises the secondary signal amplifier, this secondary signal amplifier is used for the carrier signal that this carrier signal generator has generated is amplified, and provides the carrier signal of being amplified to described second ultrasonic transducer.
15. a body sounds transfer approach comprises:
Generate audio signal and carrier signal that expectation transmits;
Come the amplitude of this audio signal is modulated by using this carrier signal;
Audio signal behind the described amplitude modulation(PAM) and this carrier signal are converted to ultrasonic signal; And
Health by the user transmits the audio signal that has been converted to ultrasonic signal near user's ear, and comes to transmit the carrier signal that has been converted to ultrasonic signal by air near user's ear.
16., wherein make to be converted to ultrasonic signal and to be sent near near the user's ear carrier signal incides user user's ear health by air then according to the method for claim 15.
17. the method according to claim 16 also comprises:
Coming near user's the ear, according to the nonlinear operation of user's body that the audio signal and the carrier signal that are converted into ultrasonic signal and be sent to by user's health with by air respectively then near the user's ear are carried out mixing, to generate audio signal.
18. the method according to claim 15 also comprises:
After carrying out amplitude modulation(PAM), respectively audio signal behind the described amplitude modulation(PAM) and described carrier signal are amplified.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR20090072395 | 2009-08-06 | ||
| KR72395/09 | 2009-08-06 | ||
| KR8995/10 | 2010-02-01 | ||
| KR1020100008995A KR101317182B1 (en) | 2009-08-06 | 2010-02-01 | Human body sound transmission apparatus and method for minimizing signal loss |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101998215A true CN101998215A (en) | 2011-03-30 |
| CN101998215B CN101998215B (en) | 2013-11-06 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN2010102473514A Expired - Fee Related CN101998215B (en) | 2009-08-06 | 2010-08-05 | Human body sound transmission apparatus and method for minimizing signal loss |
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| Country | Link |
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| KR (1) | KR101317182B1 (en) |
| CN (1) | CN101998215B (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| KR101661577B1 (en) * | 2015-06-26 | 2016-10-04 | 최용일 | Hearing assistive aids system and method and mobile communication device for discriminating left and right of earphone using human body communication in connecting between mobile communication device and individual separated earphone with left and right side |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1132622A (en) * | 1995-10-20 | 1996-10-09 | 清华大学 | Ultrasonic beat-frequency device realizing auditory perception |
| CN1303187A (en) * | 1999-11-11 | 2001-07-11 | 索尼公司 | Portable voice frequency listening equipment |
| JP2004364009A (en) * | 2003-06-05 | 2004-12-24 | Advanced Inst Of Wearable Environmental Information Networks | Data communication method and apparatus |
| US20060143004A1 (en) * | 2004-12-08 | 2006-06-29 | Sung-Eun Kim | Sound transmission system |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100842259B1 (en) * | 2006-04-21 | 2008-06-30 | 한국전자통신연구원 | Human body communication method using multi-carrier modulation |
| KR100912078B1 (en) * | 2007-05-02 | 2009-08-12 | 한국전자통신연구원 | Human body sound transmission system and method using single sound source |
| KR20110086507A (en) * | 2010-01-22 | 2011-07-28 | 한국전자통신연구원 | Apparatus for transmitting sound through human body |
-
2010
- 2010-02-01 KR KR1020100008995A patent/KR101317182B1/en active IP Right Grant
- 2010-08-05 CN CN2010102473514A patent/CN101998215B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1132622A (en) * | 1995-10-20 | 1996-10-09 | 清华大学 | Ultrasonic beat-frequency device realizing auditory perception |
| CN1303187A (en) * | 1999-11-11 | 2001-07-11 | 索尼公司 | Portable voice frequency listening equipment |
| JP2004364009A (en) * | 2003-06-05 | 2004-12-24 | Advanced Inst Of Wearable Environmental Information Networks | Data communication method and apparatus |
| US20060143004A1 (en) * | 2004-12-08 | 2006-06-29 | Sung-Eun Kim | Sound transmission system |
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| Publication number | Publication date |
|---|---|
| KR20110014948A (en) | 2011-02-14 |
| CN101998215B (en) | 2013-11-06 |
| KR101317182B1 (en) | 2013-10-15 |
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