WO2020052923A1 - Capacitive door handle sensor having an antenna for near field communication - Google Patents
Capacitive door handle sensor having an antenna for near field communication Download PDFInfo
- Publication number
- WO2020052923A1 WO2020052923A1 PCT/EP2019/072332 EP2019072332W WO2020052923A1 WO 2020052923 A1 WO2020052923 A1 WO 2020052923A1 EP 2019072332 W EP2019072332 W EP 2019072332W WO 2020052923 A1 WO2020052923 A1 WO 2020052923A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- capacitive sensor
- antenna
- nfc
- capacitive
- sensor electrode
- 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
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
- H03K17/945—Proximity switches
- H03K17/955—Proximity switches using a capacitive detector
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
- H03K17/96—Touch switches
- H03K17/962—Capacitive touch switches
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
- H04B5/70—Near-field transmission systems, e.g. inductive or capacitive transmission systems specially adapted for specific purposes
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K2217/00—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00
- H03K2217/94—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated
- H03K2217/94084—Transmission of parameters among sensors or between sensor and remote station
- H03K2217/94089—Wireless transmission
Definitions
- the invention relates to a capacitive sensor with a capacitive sensor electrode and an antenna which surrounds the capacitive sensor electrode or which is arranged in the immediate vicinity thereof and is suitable for near field communication (NFC), and its antenna
- Control elements accessible to the user are increasingly being equipped with intelligent functions, particularly in the automotive sector. This is especially true for the
- NFC Near field communication
- Bluetooth or other systems in the same place, which enables additional functionalities such as the use of virtual car keys in the form of a password stored on the smartphone.
- the capacitive sensors are to be used in addition to a wireless communication system, e.g. NFC, can be accommodated in the same housing.
- the NFC antenna which is usually in the form of an inexpensive, multi-turn conductor loop, works best when there is as little metal surface in the magnetic field as possible, which impedes field propagation.
- metal surfaces are essential due to the sensor electrodes of the capacitive sensor system.
- the capacitive sensor electrode in turn, can build up the required electrical field much worse if, for example, a surrounding ground surface is present in the direct vicinity of the electrode, which concentrates the field line course at very small distances. If, for example, an NFC antenna surrounds the capacitive electrode in a ring, this has a similar effect to one for the capacitive sensor
- a door handle arrangement for a motor vehicle is known from DE 10 2013 102 701 A1, in which the NFC antenna is used by means of electronic switches either in NFC mode for near-field communication or as a capacitive sensor electrode.
- a disadvantage is the additional circuitry for the switching device, which can also cause additional resonant circuit damping, detuning and voltage limitation in NFC operation.
- DE 101 63 778 A1 proposes an arrangement in which the switching device is dispensed with, but without avoiding the capacitive load on the sensor electrode caused by the coupling circuit of the antenna, which is extremely unfavorable for the capacitive sensor.
- a combination of an NFC system and a capacitive proximity sensor in which the NFC antenna is used in two different operating modes.
- the proximity sensor is coupled to a connection of the antenna and then used as a capacitive sensor electrode.
- the NFC antenna represents an "open end" for the capacitive sensor and a "closed end” for the NFC mode.
- the capacitive load on the NFC coupling circuit is also disadvantageous for the sensor.
- DE 10 2014 218 213 A1 discloses a communication device for a keyless vehicle access, in which the operating parameters of the antenna are evaluated, the antenna itself serving as a sensor. Since the antenna is usually designed as an inductive component, essentially only changes in the inductance can be evaluated, which can be influenced by metal objects, but which is unsuitable for the detection of human body parts.
- EP 1 795 860 B1 discloses a combined system in a vehicle handle, in which the antenna coil for data communication is simultaneously connected at one end to a capacitive sensor system, the antenna coil being coupled via a parasitic capacitance to an electrically conductive core, which acts as an extended sensor electrode serves.
- the relatively large capacity of the coupling network is disadvantageous for NFC applications.
- a sensor arrangement with a capacitive sensor device and a near-field transmission device is known, a turn 22 of a near-field transmission coil 21 rotating on a single-layer printed circuit board 30, which is coupled to control electronics 40.
- a sensor electrode 1 1 is coupled, which has a central conductor 1 1.2 and a plurality Branch conductors 1 1.1, wherein, if the capacitive sensor device is configured for capacitive detection, a potential deviating from a ground potential is then applied for cooperative control of the near-field transmission coil.
- the object of the invention is seen to significantly improve the function of the capacitive sensor system in confined spaces, for example in a (motor vehicle) door handle, that is to say to increase the sensory sensitivity without impairing the function of the NFC system.
- Claim 2 relates to an advantageous embodiment and the independent claim 3 to its intended
- the center tap of the NFC antenna is proposed as
- the main advantage is that the previously disruptive NFC antenna now acts as an auxiliary electrode. It displaces the electrical field lines in the edge areas of the sensor electrode 2, so that they now pass through a larger area and the hand of a user can be detected at a greater distance when trying to access.
- Fig. 1 shows the prior art
- Fig. 2 shows the arrangement according to the invention
- FIG. 1 schematically shows a combined system with a capacitive sensor 1 and an NFC antenna 3 enclosing the capacitive sensor electrode 2, which in turn is connected to an NFC IC via an EMC filter 7 via a common coupling network 5 known from the relevant literature 6 is connected, which works in a symmetrical operating mode because of the efficient use of energy.
- the capacitive sensor electrode 2 is severely restricted in its function by the enclosing NFC antenna 3, since this is the electrical structure built up by the electrode 2 Shielded field and restricted to very small distances. This is often no longer sufficient for a convenient operating function.
- the center tap 4 of the NFC antenna 3 is used as a feed point for an auxiliary signal that is synchronized with the measurement signal of the sensor electrode 2, so that the metal surface of the NFC antenna 3 becomes an actively driven shield electrode, which no longer hinders field propagation , but additionally supported.
- the capacitive sensor electrode is advantageous as an open grid structure without a closed one
- the center tap of the NFC antenna 4 is usually not used at all, and otherwise does not lead to NFC radio frequency in the case of symmetrical NFC transmission operation, since the two electrical halves of the symmetrically operated NFC antenna represent two partial inductors and carry an antiphase voltage. Therefore, this point 4 can either be grounded or can remain unconnected.
- any other impedance that is effective in common mode can also be set at this point without changing the operating parameters of the antenna for symmetrical NFC operation. This property naturally assumes the symmetrical operation of the antenna and the presence of a center tap.
- this point (4) is acted upon by an auxiliary signal which is useful for the function of the capacitive sensor and which is synchronized with the actual measurement signal on the sensor electrode.
- this auxiliary signal is of no importance for the function of the NFC system, since the high-frequency voltage is zero at this point in NFC operation.
- R and C can therefore take on useful values for the operation of the auxiliary electrode without influencing the adaptation network 5 in the NFC function. In this way, the desired slope of the synchronous auxiliary signal, which is not necessarily identical to the sensor signal, can be set.
- the capacitive sensor electrode 2 and the NFC antenna 3 can also be arranged in close proximity to one another without departing from the inventive concept.
- Reference list
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Near-Field Transmission Systems (AREA)
- Lock And Its Accessories (AREA)
Abstract
Description
Kapazitiver Türgriffsensor mit einer Antenne zur Nahfeldkommunikation Capacitive door handle sensor with an antenna for near field communication
Die Erfindung betrifft einen kapazitiven Sensor mit einer kapazitiven Sensorelektrode und einer die kapazitive Sensorelektrode umschließende oder in deren unmittelbarer Nähe angeordnete, zur Nahfeldkommunikation (NFC) geeigneten Antenne, sowie dessen The invention relates to a capacitive sensor with a capacitive sensor electrode and an antenna which surrounds the capacitive sensor electrode or which is arranged in the immediate vicinity thereof and is suitable for near field communication (NFC), and its antenna
Verwendung in einem Türgriff für ein Kraftfahrzeug gemäß dem nebengeordneten Use in a door handle for a motor vehicle according to the secondary
Patentanspruch 3. Claim 3.
Für den Benutzer zugängliche Bedienelemente werden insbesondere im Automobilbereich zunehmend mit intelligenten Funktionen ausgestattet. Das gilt besonders für die Control elements accessible to the user are increasingly being equipped with intelligent functions, particularly in the automotive sector. This is especially true for the
Zugangserkennung, wo kapazitive Sensoren in Türgriffen oder bedienbaren Zonen an Heck- oder Frontklappen eingebaut werden, um Zugangsversuche des Benutzers zu erkennen. Darüber hinaus finden drahtlose Identifikationseinrichtungen wie zum Beispiel Access detection, where capacitive sensors are installed in door handles or accessible zones on tailgates or front flaps to detect attempts by the user. You will also find wireless identification devices such as
Nahfeldkommunikation (NFC), Bluetooth oder andere Systeme an der gleichen Stelle Platz, was zusätzliche Funktionalitäten wie die Verwendung virtueller Autoschlüssel in Form eines auf dem Smartphone gespeicherten Passwortes ermöglicht. Near field communication (NFC), Bluetooth or other systems in the same place, which enables additional functionalities such as the use of virtual car keys in the form of a password stored on the smartphone.
Das stellt wiederum zusätzliche Anforderungen an die kapazitive Sensorik, weil sich hier besonders die Verwendung derselben konstruktiven Elemente, wie z.B. Türgriffe anbietet. Dabei soll die kapazitive Sensorik zusätzlich zu einem drahtlosen Kommunikationssystem, wie z.B. NFC, im selben Gehäuse untergebracht werden. This in turn places additional demands on the capacitive sensor technology, because here the use of the same structural elements, e.g. Offers door handles. The capacitive sensors are to be used in addition to a wireless communication system, e.g. NFC, can be accommodated in the same housing.
Dies bedeutet bei den sehr beengten Platzverhältnissen oftmals Kompromisse in der Funktionalität des kapazitiven Sensorsystems, weil ein Teil des normalerweise für die einwandfreie Funktion eines kapazitiven Sensors erforderliche Freiraumes nun durch die NFC-Antenne belegt ist, die ihrerseits für eine bestmögliche Funktion die gleiche räumliche Ausdehnung beansprucht. Beide Systeme behindern sich gegenseitig in den sensorischen Eigenschaften. This often means compromises in the functionality of the capacitive sensor system given the very cramped space conditions, because part of the space normally required for the perfect functioning of a capacitive sensor is now occupied by the NFC antenna, which in turn requires the same spatial expansion for the best possible function . Both systems interfere with each other in the sensory properties.
Die NFC-Antenne, die meistens in Form einer kostengünstigen, aus mehreren Windungen bestehenden Leiterschleife vorliegt, funktioniert am besten, wenn sich möglichst wenig Metallfläche im Magnetfeld befindet, welches die Feldausbreitung behindert. Metallflächen sind jedoch durch die Sensorelektroden des kapazitiven Sensorsystems unerlässlich. The NFC antenna, which is usually in the form of an inexpensive, multi-turn conductor loop, works best when there is as little metal surface in the magnetic field as possible, which impedes field propagation. However, metal surfaces are essential due to the sensor electrodes of the capacitive sensor system.
Die kapazitive Sensorelektrode wiederum kann das erforderliche elektrische Feld wesentlich schlechter aufbauen, wenn in direkter Umgebung der Elektrode beispielsweise eine umschließende Massefläche vorhanden ist, welche den Feldlinienverlauf auf sehr kleine Abstände konzentriert. Wenn beispielsweise eine NFC-Antenne die kapazitive Elektrode ringförmig umschließt, dann wirkt dies für den kapazitiven Sensor ähnlich wie eine The capacitive sensor electrode, in turn, can build up the required electrical field much worse if, for example, a surrounding ground surface is present in the direct vicinity of the electrode, which concentrates the field line course at very small distances. If, for example, an NFC antenna surrounds the capacitive electrode in a ring, this has a similar effect to one for the capacitive sensor
Massefläche, welche die Ausbreitung der elektrischen Feldlinien wesentlich behindert. Aus der DE 10 2013 102 701 A1 ist eine Türgriffanordnung für ein Kraftfahrzeug bekannt, bei der die NFC-Antenne mittels elektronischer Umschalter wahlweise im NFC-Betrieb zur Nahfeldkommunikation, oder als kapazitive Sensorelektrode genutzt wird. Nachteilig ist der zusätzliche Schaltungsaufwand für die Umschalteinrichtung, die außerdem im NFC-Betrieb eine zusätzliche Schwingkreisdämpfung, Verstimmung und Spannungsbegrenzung verursachen kann. Ground surface that significantly impedes the spread of the electrical field lines. A door handle arrangement for a motor vehicle is known from DE 10 2013 102 701 A1, in which the NFC antenna is used by means of electronic switches either in NFC mode for near-field communication or as a capacitive sensor electrode. A disadvantage is the additional circuitry for the switching device, which can also cause additional resonant circuit damping, detuning and voltage limitation in NFC operation.
Die DE 101 63 778 A1 schlägt eine Anordnung vor, bei der zwar auf die Umschalteinrichtung verzichtet wird, ohne jedoch die von der Ankoppelschaltung der Antenne hervorgerufene kapazitive Belastung der Sensorelektrode zu vermeiden, was für den kapazitiven Sensor aber äußerst ungünstig ist. DE 101 63 778 A1 proposes an arrangement in which the switching device is dispensed with, but without avoiding the capacitive load on the sensor electrode caused by the coupling circuit of the antenna, which is extremely unfavorable for the capacitive sensor.
Aus der WO 2013 137 892 A1 ist eine Kombination aus NFC-System und kapazitivem Näherungssensor bekannt, bei der die NFC-Antenne in zwei verschiedenen Betriebsarten benutzt wird. Der Näherungssensor wird an einen Anschluss der Antenne angekoppelt und dann als kapazitive Sensorelektrode benutzt. Die NFC-Antenne stellt für den kapazitiven Sensor ein„offenes Ende“, und für die NFC-Betriebsart ein„geschlossenes Ende“ dar. Die kapazitive Belastung der NFC-Ankoppelschaltung ist auch hier nachteilig für den Sensor. From WO 2013 137 892 A1, a combination of an NFC system and a capacitive proximity sensor is known, in which the NFC antenna is used in two different operating modes. The proximity sensor is coupled to a connection of the antenna and then used as a capacitive sensor electrode. The NFC antenna represents an "open end" for the capacitive sensor and a "closed end" for the NFC mode. The capacitive load on the NFC coupling circuit is also disadvantageous for the sensor.
Aus der DE 10 2014 218 213 A1 ist ein Kommunikationsgerät für einen schlüssellosen Fahrzeugzugang bekannt, bei der die Betriebsparameter der Antenne ausgewertet werden, wobei die Antenne selbst als Sensor dient. Da die Antenne in der Regel als induktives Bauelement ausgeführt ist, können im Wesentlichen auch nur Änderungen der Induktivität ausgewertet werden, die durch Metallgegenstände beeinflussbar ist, aber für die Erfassung menschlicher Körperteile ungeeignet ist. DE 10 2014 218 213 A1 discloses a communication device for a keyless vehicle access, in which the operating parameters of the antenna are evaluated, the antenna itself serving as a sensor. Since the antenna is usually designed as an inductive component, essentially only changes in the inductance can be evaluated, which can be influenced by metal objects, but which is unsuitable for the detection of human body parts.
Die EP 1 795 860 B1 offenbart ein kombiniertes System in einem Fahrzeuggriff, bei dem die Antennenspule zur Datenkommunikation gleichzeitig an einem Ende mit einem kapazitiven Sensorsystem verbunden ist, wobei die Antennenspule über eine parasitäre Kapazität an einen elektrisch leitfähigen Kern angekoppelt ist, der als verlängerte Sensorelektrode dient. Die relativ große Kapazität des Ankoppelnetzwerkes ist nachteilig für NFC-Anwendungen. EP 1 795 860 B1 discloses a combined system in a vehicle handle, in which the antenna coil for data communication is simultaneously connected at one end to a capacitive sensor system, the antenna coil being coupled via a parasitic capacitance to an electrically conductive core, which acts as an extended sensor electrode serves. The relatively large capacity of the coupling network is disadvantageous for NFC applications.
Aus der nachveröffentlichten DE 10 2018 106 771 A1 ist eine Sensoranordnung mit einer kapazitiven Sensorvorrichtung und einer Nahfeld-Übertragungsvorrichtung bekannt, wobei auf einer einschichtigen Leiterplatte 30 eine Windung 22 einer Nahfeld-Übertragungsspule 21 umläuft, die mit einer Steuerelektronik 40 gekoppelt ist. Mit dieser Steuerelektronik 40 ist auch eine Sensorelektrode 1 1 gekoppelt, die einen Mittelleiter 1 1.2 und eine Vielzahl an Abzweigleitern 1 1.1 aufweist, wobei, wenn die kapazitive Sensorvorrichtung zur kapazitiven Erfassung konfiguriert ist, für eine kooperative Ansteuerung der Nahfeld-Übertragungsspule dann auf ein von einem Massepotential abweichendes Potential gelegt wird. From the subsequently published DE 10 2018 106 771 A1, a sensor arrangement with a capacitive sensor device and a near-field transmission device is known, a turn 22 of a near-field transmission coil 21 rotating on a single-layer printed circuit board 30, which is coupled to control electronics 40. With this control electronics 40, a sensor electrode 1 1 is coupled, which has a central conductor 1 1.2 and a plurality Branch conductors 1 1.1, wherein, if the capacitive sensor device is configured for capacitive detection, a potential deviating from a ground potential is then applied for cooperative control of the near-field transmission coil.
Die Aufgabe der Erfindung wird darin gesehen, die Funktion des kapazitiven Sensorsystems bei beengten Platzverhältnissen, beispielsweise in einem (Kfz-)Türgriff, wesentlich zu verbessern, das heißt, die sensorische Empfindlichkeit zu erhöhen, ohne die Funktion des NFC-Systems zu beeinträchtigen. The object of the invention is seen to significantly improve the function of the capacitive sensor system in confined spaces, for example in a (motor vehicle) door handle, that is to say to increase the sensory sensitivity without impairing the function of the NFC system.
Diese Aufgabe wird mit dem Patentanspruch 1 gelöst. Anspruch 2 betrifft eine vorteilhafte Ausgestaltung und der nebengeordnete Anspruch 3 dessen bestimmungsgemäße This object is achieved with patent claim 1. Claim 2 relates to an advantageous embodiment and the independent claim 3 to its intended
Verwendung in einem (Kfz-) Türgriff. Use in a (car) door handle.
Erfindungsgemäß wird vorgeschlagen, die Mittelanzapfung der NFC-Antenne als According to the invention, the center tap of the NFC antenna is proposed as
Einspeisepunkt für ein Hilfssignal zu verwenden, welches mit dem Messsignal der kapazitiven Sensorelektrode synchronisiert ist, so dass für das kapazitive Sensorsystem die Metallfläche der NFC-Antenne zu einer aktiv angetriebenen Schirmelektrode wird, die nun die Feldausbreitung nicht mehr behindert, sondern unterstützt. To use the feed point for an auxiliary signal, which is synchronized with the measurement signal of the capacitive sensor electrode, so that for the capacitive sensor system the metal surface of the NFC antenna becomes an actively driven shield electrode, which no longer hinders field propagation but supports it.
Der wesentliche Vorteil besteht darin, dass die bislang störende NFC-Antenne nun als Hilfselektrode wirkt. Sie verdrängt die elektrischen Feldlinien in den Randbereichen der Sensorelektrode 2, so dass diese nun einen räumlich größeren Bereich durchlaufen, und die Hand eines Benutzers beim Zugangsversuch auf größere Distanz erfasst werden kann. The main advantage is that the previously disruptive NFC antenna now acts as an auxiliary electrode. It displaces the electrical field lines in the edge areas of the sensor electrode 2, so that they now pass through a larger area and the hand of a user can be detected at a greater distance when trying to access.
Die Erfindung wird anhand der Zeichnung näher erläutert: The invention is explained in more detail with reference to the drawing:
Fig. 1 zeigt den Stand der Technik Fig. 1 shows the prior art
Fig. 2 zeigt die erfindungsgemäße Anordnung Fig. 2 shows the arrangement according to the invention
Die Fig. 1 zeigt schematisch ein kombiniertes System mit einem kapazitivem Sensor 1 und einer die kapazitive Sensorelektrode 2 umschließende NFC-Antenne 3, die ihrerseits über ein aus der einschlägigen Literatur bekanntes, übliches Ankoppelnetzwerk 5 mit einem EMV- Filter 7 an ein NFC-IC 6 angeschlossen ist, welches wegen des effizienten Energieeinsatzes in einer symmetrischen Betriebsart arbeitet. 1 schematically shows a combined system with a capacitive sensor 1 and an NFC antenna 3 enclosing the capacitive sensor electrode 2, which in turn is connected to an NFC IC via an EMC filter 7 via a common coupling network 5 known from the relevant literature 6 is connected, which works in a symmetrical operating mode because of the efficient use of energy.
Die kapazitive Sensorelektrode 2 wird in ihrer Funktion durch die umschließende NFC- Antenne 3 stark eingeschränkt, da diese das durch die Elektrode 2 aufgebaute elektrische Feld abschirmt und auf sehr kleine Abstände einschränkt. Das reicht für eine komfortable Bedienfunktion oft nicht mehr aus. The capacitive sensor electrode 2 is severely restricted in its function by the enclosing NFC antenna 3, since this is the electrical structure built up by the electrode 2 Shielded field and restricted to very small distances. This is often no longer sufficient for a convenient operating function.
Die Fig. 2 zeigt eine erfindungsgemäße Anordnung. Hier wird die Mittelanzapfung 4 der NFC-Antenne 3 als Einspeisepunkt für ein Hilfssignal verwendet, das mit dem Messsignal der Sensorelektrode 2 synchronisiert ist, so dass die Metallfläche der NFC-Antenne 3 zu einer aktiv angetriebenen Schirmelektrode wird, welche nun die Feldausbreitung nicht mehr behindert, sondern zusätzlich unterstützt. Zur Vermeidung von Wirbelstromverlusten ist die kapazitive Sensorelektrode vorteilhaft als offene Gitterstruktur ohne geschlossene 2 shows an arrangement according to the invention. Here, the center tap 4 of the NFC antenna 3 is used as a feed point for an auxiliary signal that is synchronized with the measurement signal of the sensor electrode 2, so that the metal surface of the NFC antenna 3 becomes an actively driven shield electrode, which no longer hinders field propagation , but additionally supported. To avoid eddy current losses, the capacitive sensor electrode is advantageous as an open grid structure without a closed one
Leiterschleifen ausgestaltet. Conductor loops designed.
Der Mittelabgriff der NFC-Antenne 4 wird meistens überhaupt nicht verwendet, und führt im Übrigen bei symmetrischem NFC-Sendebetrieb keine NFC-Hochfrequenz, da die beiden elektrischen Hälften der symmetrisch betriebenen NFC-Antenne zwei Teil-Induktivitäten darstellen und eine gegenphasige Spannung führen. Deshalb kann dieser Punkt 4 wahlweise geerdet werden oder auch unbeschaltet bleiben. The center tap of the NFC antenna 4 is usually not used at all, and otherwise does not lead to NFC radio frequency in the case of symmetrical NFC transmission operation, since the two electrical halves of the symmetrically operated NFC antenna represent two partial inductors and carry an antiphase voltage. Therefore, this point 4 can either be grounded or can remain unconnected.
Somit kann an diesem Punkt auch jede andere im Gleichtaktbetrieb wirksame Impedanz eingestellt werden, ohne für den symmetrischen NFC-Betrieb die Betriebsparameter der Antenne zu verändern. Diese Eigenschaft setzt natürlich den symmetrischen Betrieb der Antenne und das Vorhandensein eines Mittelabgriffs voraus. This means that any other impedance that is effective in common mode can also be set at this point without changing the operating parameters of the antenna for symmetrical NFC operation. This property naturally assumes the symmetrical operation of the antenna and the presence of a center tap.
Erfindungsgemäß wird dieser Punkt (4) mit einem für die Funktion des kapazitiven Sensors nützlichen Hilfssignal beaufschlagt, welches mit dem eigentlichen Messsignal auf der Sensorelektrode synchronisiert ist. Bei vielen marktüblichen kapazitiven Sensorsystemen ist es ohne wesentlichen Zusatzaufwand möglich, dieses Hilfssignal als digitales Schaltsignal eines Gatters oder Mikrocontrollers zu diesem Zweck abzugreifen. Die angeschlossene Impedanz, die aus einem Widerstand R, einer Kapazität C und der Ausgangsimpedanz der kapazitiven Ansteuerschaltung gebildet wird, hat für die Funktion des NFC-Systems keine Bedeutung, da im NFC-Betrieb die Hochfrequenz-Spannung an diesem Punkt ohnehin Null ist. R und C können also für den Betrieb der Hilfselektrode sinnvolle Werte annehmen, ohne das Anpassungsnetzwerk 5 in der NFC-Funktion zu beeinflussen. So kann die gewünschte Flankensteilheit des synchronen, aber nicht unbedingt mit dem Sensorsignal identischen Hilfssignals eingestellt werden. According to the invention, this point (4) is acted upon by an auxiliary signal which is useful for the function of the capacitive sensor and which is synchronized with the actual measurement signal on the sensor electrode. With many commercially available capacitive sensor systems it is possible to tap this auxiliary signal as a digital switching signal of a gate or microcontroller for this purpose without any significant additional effort. The connected impedance, which is formed from a resistor R, a capacitance C and the output impedance of the capacitive drive circuit, is of no importance for the function of the NFC system, since the high-frequency voltage is zero at this point in NFC operation. R and C can therefore take on useful values for the operation of the auxiliary electrode without influencing the adaptation network 5 in the NFC function. In this way, the desired slope of the synchronous auxiliary signal, which is not necessarily identical to the sensor signal, can be set.
Ohne den Erfindungsgedanken zu verlassen, können die kapazitive Sensorelektrode 2 und die NFC- Antenne 3 auch in unmittelbarer Nähe zueinander angeordnet sein. Bezugszeichenliste The capacitive sensor electrode 2 and the NFC antenna 3 can also be arranged in close proximity to one another without departing from the inventive concept. Reference list
1 Kapazitiver Sensor 1 capacitive sensor
2 Kapazitive Sensorelektrode 2 capacitive sensor electrode
3 NFC- Antenne 3 NFC antenna
4 Mittelanzapfung der NFC-Antenne 4 Center tap of the NFC antenna
5 Anpassungsnetzwerk zwischen Antenne 3und dem NFC-Transceiver 6 5 matching network between antenna 3 and the NFC transceiver 6
6 Zur Nahfeldkommunikation geeigneter, symmetrisch betriebener Transceiver6 Symmetrically operated transceivers suitable for near field communication
7 EMC-Filter 7 EMC filters
C Anpassungskondensator C matching capacitor
R Anpassungswiderstand R matching resistance
Claims
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102018122254.8 | 2018-09-12 | ||
| DE102018122254.8A DE102018122254B3 (en) | 2018-09-12 | 2018-09-12 | Capacitive door handle sensor with an antenna for near field communication |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2020052923A1 true WO2020052923A1 (en) | 2020-03-19 |
Family
ID=67851097
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/EP2019/072332 Ceased WO2020052923A1 (en) | 2018-09-12 | 2019-08-21 | Capacitive door handle sensor having an antenna for near field communication |
Country Status (2)
| Country | Link |
|---|---|
| DE (1) | DE102018122254B3 (en) |
| WO (1) | WO2020052923A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117999591A (en) * | 2021-09-16 | 2024-05-07 | 纬湃科技有限公司 | Sensor for controlling access to a motor vehicle having an electrode surrounded by an antenna |
| US12476369B2 (en) | 2023-12-21 | 2025-11-18 | Strattec Security Corporation | Near field communication antenna module |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102020102914A1 (en) * | 2020-02-05 | 2021-08-05 | Huf Hülsbeck & Fürst Gmbh & Co. Kg | Sensor device and method for this |
| DE102020102972A1 (en) * | 2020-02-05 | 2021-08-05 | Huf Hülsbeck & Fürst Gmbh & Co. Kg | Sensor device |
| EP3945501B1 (en) | 2020-07-31 | 2023-05-03 | Continental Automotive Technologies GmbH | Access system |
| FR3131002B1 (en) | 2021-12-16 | 2024-03-29 | Vitesco Technologies | Presence detection device with radio frequency antenna, for a motor vehicle. |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10163778A1 (en) | 2001-06-27 | 2003-01-23 | Witte Velbert Gmbh & Co Kg | Door handle with integrated antenna e.g. for motor vehicle or household security, has proximity switch electrode designed as antenna coil winding |
| EP1795860A1 (en) | 2004-09-28 | 2007-06-13 | Aisin Seiki Kabushiki Kaisha | Antenna assembly and door handle unit |
| US20100315389A1 (en) * | 2009-06-12 | 2010-12-16 | Qualcomm Incorporated | Devices and methods related to a display assembly including an antenna |
| WO2013137892A1 (en) | 2012-03-15 | 2013-09-19 | Intel Corporation | Near field co (nfc) and proximity sensor for portable devices |
| DE102013102701A1 (en) | 2013-03-18 | 2014-09-18 | Huf Hülsbeck & Fürst Gmbh & Co. Kg | Door handle assembly for a motor vehicle with capacitive proximity sensor and NFC transmitter / receiver unit |
| US20150028864A1 (en) * | 2013-07-29 | 2015-01-29 | Hu Shan Auto Parts Inc. | Vehicle door handle and sensor device thereof |
| DE102014218213A1 (en) | 2014-09-11 | 2016-03-17 | Continental Automotive Gmbh | Arrangement and method for detecting the approach of an object |
| EP3016295A1 (en) * | 2014-10-31 | 2016-05-04 | Semtech Corporation | Method and device for capacitive near-field communication in mobile devices |
| DE102018106771A1 (en) | 2017-03-30 | 2018-10-04 | Huf Hülsbeck & Fürst Gmbh & Co. Kg | sensor arrangement |
-
2018
- 2018-09-12 DE DE102018122254.8A patent/DE102018122254B3/en active Active
-
2019
- 2019-08-21 WO PCT/EP2019/072332 patent/WO2020052923A1/en not_active Ceased
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10163778A1 (en) | 2001-06-27 | 2003-01-23 | Witte Velbert Gmbh & Co Kg | Door handle with integrated antenna e.g. for motor vehicle or household security, has proximity switch electrode designed as antenna coil winding |
| EP1795860A1 (en) | 2004-09-28 | 2007-06-13 | Aisin Seiki Kabushiki Kaisha | Antenna assembly and door handle unit |
| US20100315389A1 (en) * | 2009-06-12 | 2010-12-16 | Qualcomm Incorporated | Devices and methods related to a display assembly including an antenna |
| WO2013137892A1 (en) | 2012-03-15 | 2013-09-19 | Intel Corporation | Near field co (nfc) and proximity sensor for portable devices |
| DE102013102701A1 (en) | 2013-03-18 | 2014-09-18 | Huf Hülsbeck & Fürst Gmbh & Co. Kg | Door handle assembly for a motor vehicle with capacitive proximity sensor and NFC transmitter / receiver unit |
| US20150028864A1 (en) * | 2013-07-29 | 2015-01-29 | Hu Shan Auto Parts Inc. | Vehicle door handle and sensor device thereof |
| DE102014218213A1 (en) | 2014-09-11 | 2016-03-17 | Continental Automotive Gmbh | Arrangement and method for detecting the approach of an object |
| EP3016295A1 (en) * | 2014-10-31 | 2016-05-04 | Semtech Corporation | Method and device for capacitive near-field communication in mobile devices |
| DE102018106771A1 (en) | 2017-03-30 | 2018-10-04 | Huf Hülsbeck & Fürst Gmbh & Co. Kg | sensor arrangement |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117999591A (en) * | 2021-09-16 | 2024-05-07 | 纬湃科技有限公司 | Sensor for controlling access to a motor vehicle having an electrode surrounded by an antenna |
| US20240413525A1 (en) * | 2021-09-16 | 2024-12-12 | Vitesco Technologies GmbH | Sensor for controlling access to a motor vehicle, having an electrode surrounded by an antenna |
| US12476369B2 (en) | 2023-12-21 | 2025-11-18 | Strattec Security Corporation | Near field communication antenna module |
Also Published As
| Publication number | Publication date |
|---|---|
| DE102018122254B3 (en) | 2019-12-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE102018122254B3 (en) | Capacitive door handle sensor with an antenna for near field communication | |
| EP3602788B1 (en) | Sensor arrangement | |
| DE69501058T2 (en) | Common mode filtering attachment for power line connectors | |
| EP0155647B1 (en) | Antenna arrangement in the rear window of a car | |
| EP1797463B1 (en) | Device for locating metallic objects and method for adjusting such a device | |
| DE102013102701A1 (en) | Door handle assembly for a motor vehicle with capacitive proximity sensor and NFC transmitter / receiver unit | |
| DE102004047189A1 (en) | Sensor for locating metallic objects and method for evaluating measuring signals of such a sensor | |
| DE2835983A1 (en) | ELECTRIC SWITCHER | |
| EP3664046B1 (en) | Vehicle door handle with sensor device and wireless communication device | |
| DE102005035935A1 (en) | Motor vehicle door handle, has capacitors whose capacitance is selected such that influence of interfering signal at supply line in capacitance of sensor is reduced without interfering transmission of high frequency signals through coil | |
| DE102013111027A1 (en) | Multi-frequency antenna for miniaturized applications | |
| DE202012101901U1 (en) | RFID reader and device with an RFID reader | |
| DE102014220406A1 (en) | Driver circuit for an inductance and active transmitting device with a driver circuit | |
| EP3439178A1 (en) | Door handle assembly for a motor vehicle with capacitive and inductive sensor | |
| DE102005037579B4 (en) | Electronic control unit | |
| EP3735630B1 (en) | Input device comprising actuation part and electromagnetic alternating-field influencing for determining position information | |
| EP1145460A2 (en) | Device for transmitting signals in a vehicle | |
| EP2150427B1 (en) | Device for operating an electrical user on a motor vehicle | |
| DE102014200935A1 (en) | Energy supply clutch | |
| EP2936212A1 (en) | Sensor for locating metal or magnetic objects | |
| WO2007031318A1 (en) | Transponder actuatable switching device | |
| DE102018125176B4 (en) | Door handle module with an NFC initiator | |
| WO2016173863A1 (en) | Antenna, inductive charging device, electric vehicle, charging station, and inductive charging method | |
| EP1323117A1 (en) | Communication terminal | |
| DE102013216322A1 (en) | Electronic device i.e. smart connector, for vehicle for driving servomotor to control wind direction of heating-, ventilation- and air conditioning unit, has case receiving PCB, and connector connecting PCB with outer side of case by cable |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 19762913 Country of ref document: EP Kind code of ref document: A1 |
|
| NENP | Non-entry into the national phase |
Ref country code: DE |
|
| 122 | Ep: pct application non-entry in european phase |
Ref document number: 19762913 Country of ref document: EP Kind code of ref document: A1 |