(12) United States Patent
`Sacco Boschetti
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 7,394,899 B2
`Jul. 1, 2008
`
`USOO7394899B2
`
`(54)
`
`DEVICE FORTRANSFORMING ADIGITAL
`SIGNAL INTO ANACOUSTICONE, AND
`THAT MAKES USE OF A STANDARD PHASE
`MODULATION
`
`(51) Int. Cl.
`(2006.01)
`H04M I/00
`(2006.01)
`H04M 9/00
`(52) U.S. Cl. ....................................................... 379/.444
`(58) Field of Classification Search ................. 379/444,
`379/37 45; 455/404.1; 340/506-550, 53,
`34O797
`See application file for complete search history.
`References Cited
`
`(56)
`
`U.S. PATENT DOCUMENTS
`6,236,889 B1
`5/2001 Soykan et al.
`Primary Examiner Curtis Kuntz
`Assistant Examiner Phylesha L. Dabney
`(74) Attorney, Agent, or Firm Young & Thompson
`
`(57)
`ABSTRACT
`A device for transforming a digital signal into an acoustic
`signal, making use of a standard phase modulation, that com
`prises a modem chip (1) with a phase modulation of known
`kind, used until now for the data transmission via cable,
`conceived and used only for a cable connection, for acquiring
`a digital signal through a serial inlet RS232 and for modulat
`ing the same according to a standard record V.22, and an
`acoustic transducer (2) of the piezoelectric kind guided by the
`modem chip (1).
`
`20 Claims, 2 Drawing Sheets
`
`(76)
`
`Inventor:
`
`(*)
`
`Notice:
`
`Appl. No.:
`
`Paolo Sacco Boschetti, Via del
`Maggiolino, 125, Roma (IT) I-00155
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 244 days.
`10/543,381
`
`PCT Fled:
`
`Apr. 10, 2003
`
`PCT NO.:
`
`PCT/ITO3/00221
`
`S371 (c)(1),
`(2), (4) Date:
`PCT Pub. No.: WO2004/071041
`
`Jul. 26, 2005
`
`PCT Pub. Date: Aug. 19, 2004
`
`Prior Publication Data
`US 2006/O147037 A1
`Jul. 6, 2006
`
`Foreign Application Priority Data
`(30)
`(IT)
`......................... RM2OO3AOOSO
`Feb. 7, 2003
`
`
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`(21)
`(22)
`(86)
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`(87)
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`(65)
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`1
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`APPLE 1021
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`U.S. Patent
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`U.S. Patent
`U.S. Patent
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`Jul. 1, 2008
`Jul. 1, 2008
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`US 7,394,899 B2
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`US 7,394,899 B2
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`1.
`DEVICE FORTRANSFORMING A DIGITAL
`SIGNAL INTO ANACOUSTICONE, AND
`THAT MAKES USE OF A STANDARD PHASE
`MODULATION
`
`BACKGROUND OF THE INVENTION
`
`2
`with an extremely high efficiency. Due to this latter feature, it
`is widely used for low speed cable transmissions, where a
`great safety in the data transmission is required (e.g. counters
`for automatic drawing). Today, the phase modulation is used
`for the data transmission without cable only in a few cases in
`which a special owner record has been developed for the
`acoustic coupling. This implies the disadvantage that, for
`receiving, a non standard modem must be used that needs, for
`entering the net, a special approval for the telephone lines o
`each single Country and this is a limit that slows down the
`commercial development thereof. Even in the case of an
`acoustic coupling realized with a phase modulation and a non
`standard modem, the presentart has not been able to solve the
`above mentioned inconveniences (the need of a perfect align
`ment between microphone and transducer and the high Sur
`rounding noise sensibility).
`
`SUMMARY OF THE INVENTION
`
`It is the aim of the present invention to overcome above
`mentioned inconveniences by means of a deviceable to trans
`form a digital signal into an acoustic signal making use of a
`standard phase modulation, conceived so as to be inserted into
`a system for the transmission of digital signals via telephone
`by means of a simple acoustic coupling, shown in a block
`scheme in FIGS. 1 and 2, in the two data transmission variants
`through through a fix telephone and through a cellular tele
`phone.
`
`BRIEF DESCRIPTION OF THE DRAWING
`FIGURES
`
`FIG. 1 illustrates a device for transforming a digital signal
`into an acoustic signal.
`FIG. 2 illustrates a variation of a device for transforming a
`digital signal into an acoustic signal.
`
`DETAILED DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`FIG. 1 shows a device that transforms a digital signal into
`an acoustic signal, making use of a standard phase modula
`tion, and the functioning block scheme works through a fix
`telephone line, consisting of:
`a modem chip 1 with a phase modulation of known kind,
`used until now for the data transmission via cable, con
`ceived and used only for a cable connection for acquir
`ing a digital signal through a serial inlet RS232 and for
`modulating the same according to a standard record
`V22:
`an acoustic transducer 2 of the piezoelectric kind guided by
`said modem chip 1:
`a feeding and connecting circuit.
`The transmission block T shown in FIG. 1 comprises a
`telephone apparatus TF with a microphone M that can be
`reached by an acoustic signal SA, and a telephone line LT
`connects the same to the receiving block BR consisting of a
`standard modem MS for the outlet of a digital data signal SD.
`For what concerns the variant of FIG. 2, the transmission
`block T comprises, instead of the telephone apparatus TF, a
`mobile telephone apparatus TFM which, through the repeater
`R, is connected by means of the telephone line LT to the
`receiving block BR.
`
`10
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`15
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`25
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`30
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`40
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`1. Field of the Invention
`The present invention concerns a device that transforms a
`digital signal into an acoustic signal, making use of a standard
`phase modulation, and having the purpose of transmitting
`data through a fix or mobile/cellular telephone line.
`2. Description of the Related Art
`It is well known that, at present, the transmission of data
`through acoustic coupling, performed e.g. with a common
`telephone, has become a quite simple operation, in particular
`when a standard record is used. However, the known art sets
`unavoidable limits for making use of said system the reliance
`whereof remains in any case low. The limits derive from two
`critical points the technique has not yet been able to over
`CO
`the need of a perfect alignment between transmitter and
`receiver (telephone). In fact, when said alignment is not
`perfect, the data transmission shows a high percentage
`of error, as it also happens when the two surfaces are not
`in perfect contact one with the other.
`high sensibility to acoustic noise (Surrounding) and to
`vibrations. During transmission it is necessary to remain
`silent and reduce (or eliminate wherever possible) the
`Surrounding noise because it may alter the acoustic sig
`nal to be transmitted.
`The need derives from above described situation to adopt
`special precautions for reducing above mentioned inconve
`niences to the minimum, whereby they can never be com
`pletely eliminated. Some of the devices used for said purpose
`35
`are listed herein below:
`a. rubber bands, or similar accessories, for fixing the trans
`mitter and the receiver so as to assure a better mechanical
`coupling. In particular, the transmitted must be coupled
`with the microphone of the telephone receiver, for receiv
`ing and consequently transmitting on the telephone line.
`b. gaskets, adapters, Supports etc. for assuring the sealing
`between the transmitter and the telephone, in consideration
`of the great variety of possible shapes of the latter. In fact,
`some “particular telephone shapes (especially of the
`microphone) may even make the coupling impossible. Just
`think of a telephone with a modem design in which the
`receiver has a design in the shape of a point, like a pyramid.
`c. the so-called acoustic cloth puts between the transmitter
`and the telephone so as to attenuate the vibrations between
`the two “machine bodies', which are a sure source of
`transmission errors.
`As far as the kind of modulation used, there exist different
`modulation techniques, which are characterized in the modu
`lation records used, in error probabilities and transmission
`55
`speed. There are, e.g., two kinds of modulation used also for
`the transmission of data through the telephone line:
`frequency modulation (FSK)
`phase modulation (PSK).
`The frequency modulation (FSK) is the one mostly used for
`transmitting data through an acoustic coupling; it shows the
`60
`advantage of not being owner and to be able to use a common
`standard modem, on the other side, it has a low efficiency in
`terms of relationship signal/noise at equal transmission speed
`towards other modulation techniques.
`The phase modulation (PSK) is a rather efficient modula
`tion technique which allows, in theory, the data transmission
`at extremely high speed or, if used at a relatively low speed,
`
`65
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`25
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`The present invention provides the use of the standard
`phase modulation instead of the frequency modulation com
`monly used for the transmission of data of acoustic kind. This
`has been made possible making use of a modem chip (that
`males use of the standard record V.22) available on the market is
`but, as mentioned above, conceived and used only for a cable
`connection.
`The advantages of the device according to the present
`invention are many and considerable:
`the inconveniences and the respective limits of the actual to
`method are completely overcome and, consequently, it
`is made possible to perform the transmission in condi
`tions that would be considered impossible according to
`the present knowledge and that correspond to the situa
`tion of simple nearing between transmitter and receiver, is
`the device allows a reliable data transmission through a
`telephone line under the following acoustic coupling
`conditions, where no other similar data transmission
`device could succeed:
`the transducer and the microphone are physically far 20
`away, until a distance of one meter;
`the transducer and the microphone are not aligned
`(within a distance of one meter);
`the orientation of the operation fields of the transducer
`and of the microphone is diverging, as e.g. in the
`situation in which they are both resting on a plane with
`opposed orientation;
`the device according to the present invention allows a reli
`able data transmission through a telephone line under
`the following acoustic coupling conditions:
`a high surrounding noise during transmission;
`a telephone apparatus with an irregular shape that does
`not allow a perfect adherence of the microphone with
`the transducer.
`Under such conditions, any other similar device for
`the data transmission would succeed only with a con
`siderably lower or very low reliability degree.
`the device makes use of the phase modulation of the signal
`and due to the high efficiency that may be obtained from 40
`the latter, it guides an acoustic transducer (a piezoelec
`tric buzzer) of extreme simplicity and extremely low
`used power (in the range of one micro-watt), instead of
`a more expensive loudspeaker of the electromagnetic
`kind. This implies further advantages in terms of costs, 45
`lightness/encumbrance and an extremely low electric
`current consumption (fundamental in a battery-fed
`pocket-system);
`due to the extremely low power used by the device, a
`greater autonomy of the batteries is obtained: with the 50
`same autonomy batteries (or even rechargeable batter
`ies) of lower capacity may be used with advantages, also
`in this case, in terms of cost, lightness and encumbrance.
`Such advantages are particularly important when consid
`ering the industrial usefulness of the device according to the
`present invention, especially relating to mobile devices of
`tele-medicine.
`It appears evident how, due to the device according to the
`present invention, the cable-less data transmission by acous
`tic coupling through a common telephone apparatus may 60
`become a simple and extremely reliable method if considered
`to what is available at present.
`Due to the reliability obtained, it will be possible to suggest
`the new system in all situations providing great diffusion, e.g.
`also for transmitting data in a “tele-medicine' service which 65
`thus will become available even to old people with reduced
`psychomotor capacities or not completely self-sufficient.
`
`35
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`US 7,394,899 B2
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`4
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`The invention claimed is:
`1. A device for transforming a digital signal into an acoustic
`signal, comprising:
`a modem chip (1) configured to have a standard phase
`modulation of a kind for data transmission via cable and
`only for a cable connection, the modem chip being
`adapted to acquire a digital signal through a serial inlet
`RS232 and to modulate the digital signal according to a
`standard record V.22;
`a piezoelectric acoustic transducer (2) configured to be
`guided by said modem chip (1); and
`a feeding and connecting circuit, wherein the device
`employs a standard phase modulation, and the device
`does not employ frequency modulation.
`2. The device according to claim 1, wherein the piezoelec
`tric acoustic transducer (2) is not an electromagnetic loud
`speaker.
`3. The device according to claim 1, further comprising a
`telephone line for transmitting reliable data by employing
`acoustic coupling.
`4. The device according to claim 3, further comprising a
`microphone, wherein the transducer (2) and the microphone
`are separated by a distance of up to one meter.
`5. The device according to claim 4, wherein the transducer
`(2) and the microphone are not aligned.
`6. The device according to claim 4, wherein an operational
`field of the transducer (2) and the microphone diverge.
`7. The device according to claim 6, wherein the transducer
`(2) and the microphone both rest on a plane with opposed
`orientation.
`8. The device according to claim 1, wherein the transducer
`(2) is a piezoelectric buzzer.
`9. The device according to claim 1, wherein the transducer
`(2) consumes power at a magnitude of one micro watt.
`10. The device according to claim 1, further comprising:
`a telephone with a microphone that can be reached by the
`acoustic signal;
`a telephone line connected to the telephone; and
`a receiving block including a modem.
`11. The device according to claim 1, further comprising:
`a mobile telephone with a microphone that can be reached
`by the acoustic signal;
`a repeater adapted to receive signals from the telephone;
`and
`a receiving block including a modem.
`12. A tele-medical device, comprising:
`a modem chip (1) configured to have a phase modulation of
`a kind for data transmission via cable and only for a
`cable connection, the modem chip being adapted to
`acquire a digital signal through a serial inlet RS232 and
`to modulate the digital signal according to a standard
`record V.22;
`a piezoelectric acoustic transducer (2) configured to be
`guided by said modem chip (1); and
`a feeding and connecting circuit,
`wherein the device employs a standard phase modulation,
`and the device does not employ frequency modulation.
`13. The device according to claim 12, wherein the trans
`ducer (2) is not an electromagnetic loudspeaker.
`14. The device according to claim 12, further comprising a
`telephone line for transmitting reliable data by employing
`acoustic coupling.
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`US 7,394,899 B2
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`6
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`18. The device according to claim 17, wherein the trans
`15. The device according to claim 14, further comprising a
`ducer (2) and the microphone both rest on a plane with
`microphone, wherein the transducer (2) and the microphone
`opposed orientation.
`are separated by a distance of up to one meter.
`19. The device according to claim 12, wherein the trans
`16. The device according to claim 15, wherein the trans- 5 ducer (2) is a piezoelectric buzzer.
`ducer (2) and the microphone are not aligned.
`20. The device according to claim 12, wherein the trans
`ducer (2) consumes power at a magnitude of one micro watt.
`17. The device according to claim 15, wherein an opera
`k
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`.
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`tional field of the transducer (2) and the microphone diverge.
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