WO1996018969A1 - Contactless data transmission system - Google Patents
Contactless data transmission system Download PDFInfo
- Publication number
- WO1996018969A1 WO1996018969A1 PCT/DE1995/001659 DE9501659W WO9618969A1 WO 1996018969 A1 WO1996018969 A1 WO 1996018969A1 DE 9501659 W DE9501659 W DE 9501659W WO 9618969 A1 WO9618969 A1 WO 9618969A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- transmitting
- circuit
- data carrier
- data
- receiving device
- Prior art date
- Legal status (The legal status 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 status listed.)
- Ceased
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L5/00—Arrangements affording multiple use of the transmission path
- H04L5/14—Two-way operation using the same type of signal, i.e. duplex
- H04L5/143—Two-way operation using the same type of signal, i.e. duplex for modulated signals
-
- G—PHYSICS
- G06—COMPUTING OR CALCULATING; COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
- G06K7/0008—General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
-
- G—PHYSICS
- G08—SIGNALLING
- G08C—TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
- G08C17/00—Arrangements for transmitting signals characterised by the use of a wireless electrical link
- G08C17/04—Arrangements for transmitting signals characterised by the use of a wireless electrical link using magnetically coupled devices
-
- G—PHYSICS
- G08—SIGNALLING
- G08C—TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
- G08C17/00—Arrangements for transmitting signals characterised by the use of a wireless electrical link
- G08C17/06—Arrangements for transmitting signals characterised by the use of a wireless electrical link using capacity coupling
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
- H04B5/20—Near-field transmission systems, e.g. inductive or capacitive transmission systems characterised by the transmission technique; characterised by the transmission medium
- H04B5/22—Capacitive coupling
Definitions
- the invention relates to a system for contactless data transmission by means of a device for loose inductive or capacitive coupling between a transmitting / receiving device and at least one portable data carrier arrangement, the transmission of data from the data carrier arrangement to the transmitting / receiving device using modulation of the carrier signal sent from the transmitting / receiving device to the data carrier arrangement by loading the secondary circuit of the coupling device and in the transmitting / receiving device demodulation takes place.
- Such a data transmission system is known for example from EP 0 473 569 A2.
- a transmitting coil of the transmitting / receiving device is fed by an oscillator.
- the transmitting coil is loosely coupled to a receiving coil in a portable data carrier arrangement, so that an inductive transmission of energy from the transmitting / receiving device to the data carrier arrangement can take place.
- This energy transfer takes place by means of a carrier signal which on the one hand functions as a clock signal and on the other hand serves as a carrier for data from the transmitting / receiving device to the data carrier arrangement.
- the inductance or the ohmic load of the receiving coil can be changed, as a result of which the current in the secondary circuit of the coupling device and, depending on this, also the voltage at the transmitting coil of the primary circuit changes.
- This change is determined by an amplitude demodulator.
- This load modulation means that data can be transmitted from the data carrier arrangement to the transmitting / receiving device without the need for a further carrier signal.
- the transmission behavior depends on the coupling factor between the primary and the secondary circuit of the coupling device. exercise. This in turn is a function of the distance between the transmitting / receiving device and the data carrier arrangement, which can be a contactless chip card, for example.
- the basic dependence of the voltage at the transmitter coil of the primary circuit on the current through the secondary circuit is shown in FIG. In the usual circuit constellations for coupling devices, there is a transmission course which has a minimum.
- the load on the secondary circuit which can be done both by changing the inductance of the coil, the value of a resistor or the capacitance of a tuning capacitor, the secondary current changes, for example, from a value I ⁇ to a larger value I2.
- the value of the voltage on the primary circuit coil will deviate from a value Ui result in a smaller value U2, which can be detected by means of an amplitude demodulator.
- the object of the invention is therefore to provide a data transmission system in which a change in load can always be detected.
- the object is achieved by a data transmission system according to claim 1.
- Advantageous further developments are specified in the subclaims.
- phase demodulation circuit has the advantage that in the case of a load modulation around the minimum of the UI characteristic and thus in the case of a minimal or even vanishing amplitude change on the primary circuit coil, the phase change of the voltage on the primary circuit coil exhibits a maximum .
- the amplitude is additionally demodulated and in a further development a device is provided which simultaneously evaluates the amounts of the detected amplitude and phase changes, so that a demodulated output signal which can be easily evaluated is always generated.
- a particular advantage of such a system in which only the alternating field built up by the primary circuit is modulated by the data carrier arrangement, is that the modulation oscillations are derived directly from the primary oscillation and are therefore in a fixed frequency and phase relationship.
- This can be used advantageously by using the oscillation of the transmit oscillator as a reference for the demodulation.
- This allows simple and known circuits to be used, e.g. controlled rectifiers, EXOR gates, quadrature demodulators or multipliers.
- the use of the oscillation of the transmit oscillator as a reference has the advantage that the frequency selection can be improved in a simple manner.
- Show 1 shows a basic circuit of a data transmission system according to the invention
- Figure 2 shows the basic course of a U-I transfer characteristic.
- the transmission oscillator of the transmission / reception device is represented by a voltage source Uo. This feeds a series resonant circuit from a resistor Rp, a capacitor Cp and a coil Lp, which forms the primary inductance of a loosely coupled transformer.
- the secondary circuit of this inductive coupling device is formed by a parallel resonant circuit with a secondary coil formed by an inductance Lg, a capacitor Cg and a resistor Rg.
- a variable resistor Ry and a variable capacitor Cy are connected in parallel to this parallel resonant circuit.
- this voltage is supplied both to a phase demodulator circuit P and, in a further development of the invention, to an amplitude demodulator A.
- the output signals of these demodulators A, P can either be evaluated separately and, for example, the larger signal of the two can be used for further processing, or but are fed to a device 3 which evaluates the amounts of the two output signals simultaneously and thus always provides a good output signal for further processing of the data from the portable data carrier arrangement.
- the voltage UQ of the oscillator and the voltage UL of the primary circuit coil are supplied to the phase demodulator circuit P as a reference signal.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Signal Processing (AREA)
- Artificial Intelligence (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Theoretical Computer Science (AREA)
- Near-Field Transmission Systems (AREA)
Abstract
Description
Beschreibung description
System zur kontaktlosen DatenübertragungSystem for contactless data transmission
Die Erfindung betrifft ein System zur kontaktlosen Datenüber¬ tragung mittels einer Einrichtung zur losen induktiven oder kapazitiven Kopplung zwischen einer Sende/Empfangs-Einrich¬ tung und zumindest einer tragbaren Datenträgeranordnung, wobei die Übertragung von Daten von der Datenträgeranordnung zur Sende/Empfangs-Einrichtung mittels Modulation des von der Sende/Empfangs-Einrichtung zur Datenträgeranordnung gesende¬ ten Trägersignals durch Belastung des Sekundärkreises der Koppeleinrichtung und in der Sende/Empfangs-Einrichtung eine Demodulation erfolgt.The invention relates to a system for contactless data transmission by means of a device for loose inductive or capacitive coupling between a transmitting / receiving device and at least one portable data carrier arrangement, the transmission of data from the data carrier arrangement to the transmitting / receiving device using modulation of the carrier signal sent from the transmitting / receiving device to the data carrier arrangement by loading the secondary circuit of the coupling device and in the transmitting / receiving device demodulation takes place.
Ein solches DatenübertragungsSystem ist beispielsweise aus der EP 0 473 569 A2 bekannt. Dort wird eine Sendespule der Sende/Empfangs-Einrichtung von einem Oszillator gespeist. Die Sendespule ist lose mit einer Empfangsspule in einer tragba- ren Datenträgeranordnung gekoppelt, so daß eine induktive Übertragung von Energie von der Sende/Empfangs-Einrichtung zur Datenträgeranordnung stattfinden kann. Diese Energieüber¬ tragung erfolgt mittels eines Trägersignals, das einerseits als Taktsignal fungiert und andererseits als Träger für Daten von der Sende/Empfangs-Einrichtung zur Datenträgeranordnung dient. In der Datenträgeranordnung kann gesteuert von einem Modulator die Induktivität oder die ohmsche Belastung der Empfangsspule verändert werden, wodurch sich der Strom im Sekundärkreis der Koppeleinrichtung und davon abhängig auch die Spannung an der Sendespule des Primärkreises ändert.Such a data transmission system is known for example from EP 0 473 569 A2. There, a transmitting coil of the transmitting / receiving device is fed by an oscillator. The transmitting coil is loosely coupled to a receiving coil in a portable data carrier arrangement, so that an inductive transmission of energy from the transmitting / receiving device to the data carrier arrangement can take place. This energy transfer takes place by means of a carrier signal which on the one hand functions as a clock signal and on the other hand serves as a carrier for data from the transmitting / receiving device to the data carrier arrangement. Controlled by a modulator in the data carrier arrangement, the inductance or the ohmic load of the receiving coil can be changed, as a result of which the current in the secondary circuit of the coupling device and, depending on this, also the voltage at the transmitting coil of the primary circuit changes.
Diese Änderung wird durch einen Amplituden-Demodulator ermit¬ telt. Durch diese Belastungsmodulation können also Daten von der Datenträgeranordnung zur Sende/Empfangs-Einrichtung über¬ tragen werden ohne daß ein weiteres Trägersignal nötig wäre.This change is determined by an amplitude demodulator. This load modulation means that data can be transmitted from the data carrier arrangement to the transmitting / receiving device without the need for a further carrier signal.
Allerdings hängt das Übertragungsverhalten vom Koppelfaktor zwischen dem Primär- und dem Sekundärkreis der Koppeleinrich- tung ab. Dieser ist wiederum eine Funktion des Abstands zwi¬ schen der Sende/Empfangs-Einrichtung und der Datenträgeran¬ ordnung, die beispielsweise eine kontaktlose Chipkarte sein kann. Die prinzipielle Abhängigkeit der Spannung an der Sen- despule des Primärkreises vom Strom durch den Sekundärkreis ist in Figur 2 dargestellt. Bei üblichen Schaltungskonstella¬ tionen für Koppeleinrichtungen ergibt sich ein Übertragungs¬ verlauf, der ein Minimum aufweist. Durch Variation der Bela¬ stung des Sekundärkreises, was sowohl durch Veränderung der Induktivität der Spule, des Werts eines Widerstands oder der Kapazität eines Abstimmkondensators erfolgen kann, ändert sich der Sekundärstrom beispielsweise von einem Wert I^ zu einem größeren Wert I2. Wenn sich die Datenträgeranordnung in einem geeigneten Abstand zur Sende/Empfangs-Einrichtung be- findet und damit der Koppelfaktor sich derart ergibt, daß die Werte im abfallenden Ast der U-I-Kennlinie liegen, wird sich der Wert der Spannung an der Primärkreisspule von einem Wert Ui zu einem kleineren Wert U2 ergeben, was mittels eines Amplituden-Demodulators detektiert werden kann.However, the transmission behavior depends on the coupling factor between the primary and the secondary circuit of the coupling device. exercise. This in turn is a function of the distance between the transmitting / receiving device and the data carrier arrangement, which can be a contactless chip card, for example. The basic dependence of the voltage at the transmitter coil of the primary circuit on the current through the secondary circuit is shown in FIG. In the usual circuit constellations for coupling devices, there is a transmission course which has a minimum. By varying the load on the secondary circuit, which can be done both by changing the inductance of the coil, the value of a resistor or the capacitance of a tuning capacitor, the secondary current changes, for example, from a value I ^ to a larger value I2. If the data carrier arrangement is at a suitable distance from the transmitting / receiving device and the coupling factor is such that the values lie in the falling branch of the UI characteristic curve, the value of the voltage on the primary circuit coil will deviate from a value Ui result in a smaller value U2, which can be detected by means of an amplitude demodulator.
Es kann sich jedoch ein Übertragungsverhalten der Koppelein¬ richtung ergeben, bei dem eine Änderung des Sekundärstroms von einem Wert I3 auf einen größeren Wert I4 zu einer Span¬ nungsänderung an der Primärkreisspule von einem Wert U3 auf einen größeren Wert U4 und damit zu einer Phasenumkehr der Wirkung führt. Besonders negativ ist es, wenn bei einem bestimmten Abstand und damit Koppelfaktor sich die Spannung U5 und U6 bei einer Änderung des Stroms 15 und 16 nicht unterscheiden, da ein Spannungswert im abfallenden Ast und der andere bereits im ansteigenden Ast auf gleicher Höhe der Übertragungskennlinie liegt. Es würden sich also trotz Be¬ lastungsänderung keine Daten detektieren lassen.However, there may be a transmission behavior of the coupling device in which a change in the secondary current from a value I3 to a larger value I4 to a voltage change in the primary circuit coil from a value U3 to a larger value U4 and thus to a phase reversal of the Effect. It is particularly negative if, at a certain distance and thus coupling factor, the voltage U5 and U6 do not differ when the current 15 and 16 changes, since one voltage value in the falling branch and the other in the rising branch is at the same level as the transmission characteristic. Despite the change in load, no data would therefore be detectable.
Aufgabe der Erfindung ist es damit, ein Datenübertragungs- System anzugeben, bei dem immer eine Belastungsänderung detektiert werden kann. Die Aufgabe wird durch ein Datenύbertragungssystem gemäß Anspruch 1 gelöst. Vorteilhafte Weiterbildungen sind in den Unteransprüchen angegeben.The object of the invention is therefore to provide a data transmission system in which a change in load can always be detected. The object is achieved by a data transmission system according to claim 1. Advantageous further developments are specified in the subclaims.
Die Verwendung einer Phasen-Demodulationsschaltung hat den Vorteil, daß im Falle einer Belastungs-Modulation um das Minimum der U-I-Kennlinie herum und damit im Falle einer minimalen oder gar verschwindenden Amplitudenänderung an der Primärkreisspule die Phasenänderung der Spannung an der Pri- märkreisspule ein Maximum aufweist.The use of a phase demodulation circuit has the advantage that in the case of a load modulation around the minimum of the UI characteristic and thus in the case of a minimal or even vanishing amplitude change on the primary circuit coil, the phase change of the voltage on the primary circuit coil exhibits a maximum .
In vorteilhafter Weiterbildung wird zusätzlich die Amplitude demoduliert und in einer weiteren Fortbildung ist eine Vor¬ richtung vorgesehen, die die Beträge der detektierten Ampli- tuden- und Phasenänderungen gleichzeitig bewertet, so daß immer ein demoduliertes Ausgangssignal, das gut auswertbar ist erzeugt wird.In an advantageous development, the amplitude is additionally demodulated and in a further development a device is provided which simultaneously evaluates the amounts of the detected amplitude and phase changes, so that a demodulated output signal which can be easily evaluated is always generated.
Ein besonderer Vorteil eines solchen Systems, bei dem nur das vom Primärkreis aufgebaute Wechselfeld von der Datenträgeran¬ ordnung moduliert wird, liegt darin, daß die Modulations- Schwingungen direkt aus der Primär-Schwingung abgeleitet sind und dashalb in festem Frequenz- und Phasenverhältnis dazu stehen. Dies läßt sich vorteilhaft nutzen, indem die Schwin- gung des Sende-Oszillators als Referenz für die Demodulation genutzt wird. Dadurch können einfache und bekannte Schaltun¬ gen eingesetzt werden, wie z.B. gesteuerte Gleichrichter, EXOR-Gatter, Quadraturdemodulatoren oder Multiplizierer. Systemtechnish bietet die Verwendung der Schwingung des Sende-Oszillators als Referenz den Vorteil, daß die Frequenz- Selektion auf einfache Weise verbessert werden kann.A particular advantage of such a system, in which only the alternating field built up by the primary circuit is modulated by the data carrier arrangement, is that the modulation oscillations are derived directly from the primary oscillation and are therefore in a fixed frequency and phase relationship. This can be used advantageously by using the oscillation of the transmit oscillator as a reference for the demodulation. This allows simple and known circuits to be used, e.g. controlled rectifiers, EXOR gates, quadrature demodulators or multipliers. Systemtechnically, the use of the oscillation of the transmit oscillator as a reference has the advantage that the frequency selection can be improved in a simple manner.
Die Erfindung wird nachfolgend anhand eines Ausführungsbei- spiels mit Hilfe von Figuren näher erläutert.The invention is explained in more detail below on the basis of an exemplary embodiment with the aid of figures.
Dabei zeigen Figur 1 eine Prinzipschaltung eines erfindungsgemäßen Daten¬ übertragungssystems undShow 1 shows a basic circuit of a data transmission system according to the invention and
Figur 2 den prinzipiellen Verlauf einer U-I-Übertragungε- Kennlinie.Figure 2 shows the basic course of a U-I transfer characteristic.
Die Figur 1 zeigt in einer Prinzipdarstellung ein erfindungs¬ gemäßes Datenübertragungssystem, in der auf der linken Seite die Sende/Empfangs-Einrichtung 1 und auf der rechten Seite das Sende- und Empfangsteil 2 einer tragbaren Datenträgeran¬ ordnung gezeigt ist. Sowohl die Sende/Empfangs-Einrichtung 1 als auch die tragbare Datenträgeranσrdnung enthalten natür¬ lich weitere Bestandteile, die für die Erfindung jedoch nicht wesentlich sind. Der Sendeoszillator der Sende/Empfangs-Ein- richtung ist durch eine Spannungsquelle Uo dargestellt. Diese speist einen Serienschwingkreis aus einem Widerstand Rp, einem Kondensator Cp und einer Spule Lp, die die Primärinduk¬ tivität eines lose gekoppelten Übertragers bildet. Der Sekun¬ därkreis dieser induktiven Koppeleinrichtung ist durch einen Parallelschwingkreis mit einer durch eine Induktivität Lg gebildeten Sekundärspule, einem Kondensator Cg und einem Widerstand Rg gebildet. Diesem Parallelschwingkreis ist ein veränderbarer Widerstand Ry und ein veränderbarer Kondensator Cy parallel geschalte . Durch Veränderung entweder des verän- derbaren Widerstandes Ry und/oder des veränderbaren Kondensa¬ tors Cy läßt sich die Belastung der Koppeleinrichtung und damit der Strom Ig durch die Sekundärkreisspule Lg verändern. Dadurch ändert sich jedoch auch abhängig von dem Kopplungs- faktor k, der wiederum vom Abstand zwischen der Sende/Emp- fangs-Einrichtung und der tragbaren Datenträgeranordnung abhängt, die Spannung Uj_. an der Primärkreisspule Lp. Diese Spannung wird in erfindungsgemäßer Weise sowohl einer Phasen- Demodulatorschaltung P als auch -in Weiterbildung der Erfin¬ dung- einem Amplituden-Demodulator A zugeführt. Die Ausgangs- Signale dieser Demodulatoren A, P können entweder getrennt ausgewertet werden und beispielsweise jeweils das größere Signal der beiden zur Weiterverarbeitung benutzt werden, oder aber einer Vorrichtung 3 zugeführt werden, die die Beträge der beiden AusgangsSignale gleichzeitig bewertet und somit immer ein gutes Ausgangssignal zur Weiterverarbeitung der Daten von der tragbaren Datenträgeranordnung bereitstellt. Der Phasen-Demodulatorschaltung P werden als Referenzsignal die Spannung UQ des Oszillators und die Spannung UL der Pri¬ märkreisspule zugeführt. 1 shows a basic illustration of a data transmission system according to the invention, in which the transmitting / receiving device 1 is shown on the left side and the transmitting and receiving part 2 of a portable data carrier arrangement is shown on the right side. Both the transmitting / receiving device 1 and the portable data carrier arrangement naturally contain further components, which, however, are not essential for the invention. The transmission oscillator of the transmission / reception device is represented by a voltage source Uo. This feeds a series resonant circuit from a resistor Rp, a capacitor Cp and a coil Lp, which forms the primary inductance of a loosely coupled transformer. The secondary circuit of this inductive coupling device is formed by a parallel resonant circuit with a secondary coil formed by an inductance Lg, a capacitor Cg and a resistor Rg. A variable resistor Ry and a variable capacitor Cy are connected in parallel to this parallel resonant circuit. By changing either the changeable resistance Ry and / or the changeable capacitor Cy, the load on the coupling device and thus the current Ig through the secondary circuit coil Lg can be changed. As a result, however, the voltage Uj_ also changes as a function of the coupling factor k, which in turn depends on the distance between the transmitting / receiving device and the portable data carrier arrangement. on the primary circuit coil Lp. In accordance with the invention, this voltage is supplied both to a phase demodulator circuit P and, in a further development of the invention, to an amplitude demodulator A. The output signals of these demodulators A, P can either be evaluated separately and, for example, the larger signal of the two can be used for further processing, or but are fed to a device 3 which evaluates the amounts of the two output signals simultaneously and thus always provides a good output signal for further processing of the data from the portable data carrier arrangement. The voltage UQ of the oscillator and the voltage UL of the primary circuit coil are supplied to the phase demodulator circuit P as a reference signal.
Claims
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE4444984A DE4444984C1 (en) | 1994-12-16 | 1994-12-16 | Contactless data transmission system using inductive or capacitive coupling |
| DEP4444984.4 | 1994-12-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1996018969A1 true WO1996018969A1 (en) | 1996-06-20 |
Family
ID=6536064
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/DE1995/001659 Ceased WO1996018969A1 (en) | 1994-12-16 | 1995-11-24 | Contactless data transmission system |
Country Status (2)
| Country | Link |
|---|---|
| DE (1) | DE4444984C1 (en) |
| WO (1) | WO1996018969A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000341884A (en) * | 1999-04-07 | 2000-12-08 | Stmicroelectronics Sa | Electromagnetic transponder operating by very close coupling |
| AT501055B1 (en) * | 2005-04-07 | 2006-06-15 | Univ Graz Tech | Demodulating load modified signals in system and reading device, involves supplying of high frequency carrier signal to transmitting antenna and demodulation of carrier signal and sum signal |
| US7751860B2 (en) | 2004-01-14 | 2010-07-06 | Peter Symons | Variable configuration apparatus |
| US8290463B2 (en) | 2009-09-14 | 2012-10-16 | ConvenientPower HK Ltd. | Universal demodulation and modulation for data communication in wireless power transfer |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19637964A1 (en) * | 1996-09-18 | 1998-03-19 | Diehl Ident Gmbh | Device for inductive high-frequency data exchange |
| NL1006493C2 (en) * | 1997-07-04 | 1999-01-05 | Hedon Electronic Developments | Data exchange system between Smart Card and read/write unit |
| FR2790154A1 (en) * | 1999-02-23 | 2000-08-25 | Innovatron Electronique | Terminal for contactless communication by induction with portable objects, comprising phase demodulation detector |
| FR2792136B1 (en) | 1999-04-07 | 2001-11-16 | St Microelectronics Sa | DUPLEX TRANSMISSION IN AN ELECTROMAGNETIC TRANSPONDER SYSTEM |
| FR2796782A1 (en) * | 1999-07-20 | 2001-01-26 | St Microelectronics Sa | SIZING OF AN ELECTROMAGNETIC TRANSPONDER SYSTEM FOR DEDICATED OPERATION IN REMOTE COUPLING |
| FR2796781A1 (en) * | 1999-07-20 | 2001-01-26 | St Microelectronics Sa | DIMENSIONING OF AN ELECTROMAGNETIC TRANSPONDER SYSTEM FOR HYPERPROXIMITY OPERATION |
| US7049935B1 (en) | 1999-07-20 | 2006-05-23 | Stmicroelectronics S.A. | Sizing of an electromagnetic transponder system for a dedicated distant coupling operation |
| FR2808942B1 (en) | 2000-05-12 | 2002-08-16 | St Microelectronics Sa | VALIDATION OF THE PRESENCE OF AN ELECTROMAGNETIC TRANSPONDER IN THE FIELD OF A PHASE DEMODULATION READER |
| US20030169169A1 (en) | 2000-08-17 | 2003-09-11 | Luc Wuidart | Antenna generating an electromagnetic field for transponder |
| DE102008011582B4 (en) * | 2008-02-28 | 2012-10-31 | Sew-Eurodrive Gmbh & Co. Kg | Data transmission device and system |
| US8339139B2 (en) | 2010-01-29 | 2012-12-25 | Infineon Technologies Ag | System and method for testing a circuit |
| US8660489B2 (en) | 2010-01-29 | 2014-02-25 | Infineon Technologies Austria Ag | System and method for receiving data across an isolation barrier |
| CA2793377C (en) * | 2010-04-06 | 2016-05-24 | Widex A/S | Monitoring device and a method for wireless data and power transmission in a monitoring device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4654658A (en) * | 1984-08-03 | 1987-03-31 | Walton Charles A | Identification system with vector phase angle detection |
| US4656472A (en) * | 1985-01-23 | 1987-04-07 | Walton Charles A | Proximity identification system with power aided identifier |
| EP0312168A1 (en) * | 1987-10-12 | 1989-04-19 | N.V. Nederlandsche Apparatenfabriek NEDAP | A method and an apparatus for electronically identifying articles moving along a surface |
| EP0473569A2 (en) * | 1990-08-23 | 1992-03-04 | Mikron Gesellschaft Für Integrierte Mikroelektronik Mbh | Contactless, inductive data transmission system |
-
1994
- 1994-12-16 DE DE4444984A patent/DE4444984C1/en not_active Expired - Fee Related
-
1995
- 1995-11-24 WO PCT/DE1995/001659 patent/WO1996018969A1/en not_active Ceased
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4654658A (en) * | 1984-08-03 | 1987-03-31 | Walton Charles A | Identification system with vector phase angle detection |
| US4656472A (en) * | 1985-01-23 | 1987-04-07 | Walton Charles A | Proximity identification system with power aided identifier |
| EP0312168A1 (en) * | 1987-10-12 | 1989-04-19 | N.V. Nederlandsche Apparatenfabriek NEDAP | A method and an apparatus for electronically identifying articles moving along a surface |
| EP0473569A2 (en) * | 1990-08-23 | 1992-03-04 | Mikron Gesellschaft Für Integrierte Mikroelektronik Mbh | Contactless, inductive data transmission system |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000341884A (en) * | 1999-04-07 | 2000-12-08 | Stmicroelectronics Sa | Electromagnetic transponder operating by very close coupling |
| US7751860B2 (en) | 2004-01-14 | 2010-07-06 | Peter Symons | Variable configuration apparatus |
| US8306583B2 (en) | 2004-01-14 | 2012-11-06 | J.M. Stanneck, Limited Liability Company | Variable configuration apparatus |
| AT501055B1 (en) * | 2005-04-07 | 2006-06-15 | Univ Graz Tech | Demodulating load modified signals in system and reading device, involves supplying of high frequency carrier signal to transmitting antenna and demodulation of carrier signal and sum signal |
| WO2006105565A1 (en) * | 2005-04-07 | 2006-10-12 | Technische Universität Graz | Method for demodulating and reading device for evaluating load-modulated signals |
| US8290463B2 (en) | 2009-09-14 | 2012-10-16 | ConvenientPower HK Ltd. | Universal demodulation and modulation for data communication in wireless power transfer |
Also Published As
| Publication number | Publication date |
|---|---|
| DE4444984C1 (en) | 1995-12-14 |
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