The present disclosure relates generally to electronic devices and more precisely to electronic devices integrating RFID (Radio Frequency Identification) technology.
Contactless technologies are very widespread and are widely used in transport and access control applications. The trend is to group, as much as possible, functionalities (traditionally hosted by contactless cards or IC cards) on a single device such as a mobile phone.
There is a need to improve contactless access devices and more particularly access devices equipped with RFID technology.
One embodiment provides a device comprising a frequency demodulator and an amplitude demodulator, the device being configured to use, in a first mode, both demodulators in parallel and to activate an RFID card mode or a Qi charger mode based on results provided by said demodulators.
One embodiment provides a method implemented by a device comprising a frequency demodulator and an amplitude demodulator, in which the device uses, in a first mode, both demodulators in parallel and, in a second mode, both demodulators successively.
According to an embodiment, both frequency and amplitude demodulators also include load modulators/demodulators.
According to an embodiment, in a second mode, both frequency and amplitude demodulators operate successively.
According to an embodiment, a load modulator of the device is used when the device communicates with an external RFID A type apparatus configured in reader mode.
According to an embodiment, said load modulator is used when the device is charged by an external apparatus and when it emulates an RFID card configured in type A.
According to an embodiment, a Qi analog front end of the device is adapted to frequency modulate or amplitude modulate data when the device is in the second mode, the frequency modulated data being used to communicate with a Qi charger device and the amplitude modulated data being used to communicate with an RFID device configured in card mode.
According to an embodiment, the demodulator in amplitude is used to demodulate a response, in load modulation, of an external A type apparatus configured in card mode.
According to an embodiment, the amplitude demodulator is used to demodulate a command received from an external apparatus configured in reader mode.
According to an embodiment, the frequency demodulator is used to demodulate a response received from an external B type apparatus configured in card mode.
According to an embodiment, the frequency demodulator is used to demodulate a digital ping or any subsequent data packet received from an external charging apparatus.
According to an embodiment, the frequency demodulator is used to demodulate a response received from an external charge apparatus.
According to an embodiment, when it detects an external field on an antenna, checks whether that field comes from an RFID apparatus or from a Qi apparatus.
According to an embodiment, the check is made by emitting periodic interrogation frames in RFID mode and Qi mode.
The foregoing features and advantages, as well as others, will be described in detail in the following description of specific embodiments given by way of illustration and not limitation with reference to the accompanying drawings, in which:
Like features have been designated by like references in the various figures. In particular, the structural and/or functional features that are common among the various embodiments may have the same references and may dispose identical structural, dimensional and material properties.
For the sake of clarity, only the operations and elements that are useful for an understanding of the embodiments described herein have been illustrated and described in detail. In particular, the circuits which are qualified by their respective functions are not structurally detailed.
Unless indicated otherwise, when reference is made to two elements connected together, this signifies a direct connection without any intermediate elements other than conductors, and when reference is made to two elements coupled together, this signifies that these two elements can be connected or they can be coupled via one or more other elements.
In the following disclosure, unless indicated otherwise, when reference is made to absolute positional qualifiers, such as the terms “front,” “back,” “top,” “bottom,” “left,” “right,” etc., or to relative positional qualifiers, such as the terms “above,” “below,” “higher,” “lower,” etc., or to qualifiers of orientation, such as “horizontal,” “vertical,” etc., reference is made to the orientation shown in the figures.
Unless specified otherwise, the expressions “around,” “approximately,” “substantially” and “in the order of” signify within 10%, and preferably within 5%.
In the present description, it is proposed to take advantage of the fact that Qi technology (which corresponds to a standard developed by the Wireless Power Consortium for the transmission of wireless energy) is very widely developed in new models of smartphones. Qi technology is particularly interesting because it works for a frequency band including the Low Frequency (LF) (100 kHz to 200 kHz). In the present description, it is thus sought to establish LF communications by RFID technology by using some of the components of the circuit dedicated to the Qi technology.
The system 11 illustrated in
According to an embodiment, the device 13 is a mobile phone, for example a smartphone, or a tablet computer.
According to the embodiment illustrated in
According to the embodiment illustrated in
According to an application example, the embodiments apply to transport systems and to access control, for example, to doors of buildings equipped with Low Frequency (LF) technology.
When the device 13 illustrated in
When the device 13 is in standby, it should still be capable of detecting the presence of an RFID reader, an RFID card, a chargeable apparatus or a charger apparatus.
The timing diagram illustrated in
According to the embodiment illustrated in
During intervals 25, the device 13 is in listener mode for apparatuses in reader mode or charger apparatuses within range.
In case the device 13 detects a field (block 61, Field detected), it activates (block 63, Go to active mode), by exiting the standby mode and responds to the reader or charger apparatus depending on the detected technology.
More precisely, the device 13 comprises two demodulators, one demodulator adapted to demodulate an On-Off Keying (OOK) modulation and one demodulator adapted to demodulate a Frequency Shift Keying (FSK) modulation. The device 13 is in normal mode when both demodulators are started (block 65, Start OOK and FSK demodulators).
In order to respond to the reader or charger apparatus, the device 13 detects the technology of the apparatus within the range, and more precisely the type of modulation it is based on. Thus, the device 13 detects the On-Off Keying (OOK) modulation (block 67, OOK detected) or the Frequency Shift Keying (FSK) modulation (block 73, FSK detected).
The response of the device 13 is adapted to the detected modulation type of the apparatus.
If a type A is detected, based on start of frame, in addition to the OOK modulation, the device 13 responds by sending an answer with a load modulation according to RFID standard (block 69, Type A detected based on Start of Frame: Send answer with Load Modulation according to RFID standard).
If a type B is detected, based on start of frame, in addition to the OOK modulation, the device 13 responds by turning on the field after field off the detection and by answering according to RFID standard using FSK modulation (block 71, Type B detected based on Start of Frame: Turn on field after field off detection and answer according to RFID standard using FSK).
If a FSK modulation is detected, the device 13 responds by answering with the load modulation according to Qi standard (block 75, Qi charger: Answer with Load Modulation according to Qi standard).
According to the embodiment illustrated in
A frame 27 is, for example, made up of a succession of two emission bursts 29 and 31, burst 29 (LF RFID REQUEST) being configured to generate a field understandable by card mode apparatuses and burst 31 (Reverse Qi) being configured to generate a field understandable by chargeable apparatuses.
In other words, during a frame 27, the device 13 successively implements two emission bursts 29 and 31 each representative of a type of technology (Qi or RFID). The types of technologies targeted by the bursts are successively RFID technology and Qi technology.
According to the embodiment illustrated in
According to the embodiment illustrated in
According to the embodiment illustrated in
According to the embodiment illustrated in
According to one embodiment, each pulse 23 has a duration of between 50 microseconds (μs) and 100 μs, for example of the order of 70 μs and each burst 29, 31 has a duration of between 50 milliseconds (ms) and 100 ms, for example of the order of 70 ms. The interval 25 and the wait time 33 have a duration of between 200 ms and 1 s.
The communication circuit 35 is coupled to an antenna 37 (Antenna) via matching circuit 39 (Matching circuit). The communication circuit 35 can also be coupled to an application processor 41 (AP) and/or to a secure element 43 (SE).
According to the embodiment shown in
According to an embodiment, the controller 45 comprises coding circuits dedicated to the Qi technology.
According to the embodiment illustrated in
In such a mode, the application processor runs (link a)I) the Low frequency RFID reader wireless application using the controller 45.
The controller 45 uses the RFID reader wireless receiver/transmitter 47 to construct the low frequency RFID reader wireless commands or LF RFID RW commands (link a)II).
The controller 45 uses the TX drivers 53 and the analog front end 51 to generate the LF RFID RW commands according to the A type, using an On-Off Keying modulation (OOK Type A command a)III,
The responses (LM Tag responses,
According to an embodiment, not shown, the responses from the external apparatus in card mode to the device 13 are demodulated by the Qi Demodulator 55.
The controller 45 then uses the RFID reader wireless coder/decoder 47 to decode the external apparatus in card mode responses (link a)V) and to forward the corresponding data to the application processor 41 (link a)VI).
During this operating process, the controller 45 may use the secure element 43 to perform any required cryptographic operation.
After establishing contact between the device 13 and the apparatus within the range, they both communicate by sending successive commands and responses.
According to the embodiment illustrated in
According to the embodiment illustrated in
In such a mode, the application processor runs (link b)I) the Low frequency RFID reader wireless application using the controller 45.
The controller 45 uses the RFID reader wireless receiver/transmitter 47 to build the Low frequency RFID reader wireless commands or LF RFID RW commands (link b)II).
The controller 45 uses the TX drivers 53 and the analog front end 51 to generate the LF RFID RW commands according to the B type, by the generation of a magnetic field, using an On-Off keying amplitude modulation (OOK Type B Command b)III,
After generating the command, the device 13 stop its magnetic field and wait for an answer from the external apparatus.
The responses from the external apparatus in card mode to the device 13 (FSK Type B Responses,
The controller 45 then uses the RFID reader wireless receiver/transmitter 47 to decode the external apparatus in card mode responses (link b)V) and to forward the corresponding data to the application processor 41 (link b)VI).
During this operating process, the controller 45 may use the secure element 43 to perform any required cryptographic operation.
After establishing contact between the device 13 and the apparatus within the range, they both communicate by sending successive commands and responses.
According to the embodiment illustrated in
In such a mode, the application processor runs (link c)I) the Low frequency RFID card emulation application using the controller 45.
The commands from the external apparatus in reader mode to the device 13 are demodulated via the RFID demodulator 59 (link c)II), using an on-off keying amplitude demodulation.
The controller 45 then uses the RFID card emulation coder/decoder 49 to decode the external apparatus commands (link c)III) and uses the RFID card emulation coder/decoder 49 to build the responses (link c)IV).
The controller 45 uses the load modulator 57 to generate the response according to the A type with the apparatus in reader mode via the matching circuit 39, using a load modulation (link c)V).
During this operating process, the controller 45 may use the secure element 43 to perform any required cryptographic operation.
According to the embodiment illustrated in
In such a mode, the application processor runs (link d)I) the Low frequency RFID card emulation application using the controller 45.
The commands from the external apparatus in reader mode to the device 13 are demodulated using an on-off keying demodulation via the RFID demodulator 59 (link d)II).
The controller 45 then uses the RFID card emulation coder/decoder 49 to decode the external apparatus commands (link d)III) and uses the RFID card emulation coder/decoder 49 to build the responses (link d)IV).
The controller 45 uses the TX drivers 53 and the analog front end 51 to generate the response according to the B type with the apparatus in reader mode via the matching circuit 39, using an Frequency-Shift Keying modulation (FSK modulation) (link d)V).
During this operating process, the controller 45 may use the secure element 43 to perform any cryptographic operation required.
According to the embodiment illustrated in
In such a mode, the Qi analog ping from the external apparatus in charger mode to the device 13 is demodulated, using an FSK demodulation via the Qi demodulator 55 and decoded by the controller 45 (link e)I).
The controller 45 uses the load modulator 57 to generate the responses via the matching circuit 39 (link e)II).
Then, the device 13 is being charged and the controller 45 communicates monitoring data to the application processor 41 (link e)III).
During this operating process, the controller 45 may use the secure element 43 in case it is needed to perform an authentication.
According to the embodiment illustrated in
According to the embodiment illustrated in
In such a mode, the controller 45 sends, using an FSK modulation (link f)I) the digital Qi ping (Digital ping f)I,
The response from the external apparatus (LM Answer from the device to be charged,
Then, the device 13 charges the apparatus within range and the controller 45 communicates monitoring data to the application processor 41 (link f)III).
During this operating process, the controller 45 may use the secure element 43 in case it is needed to perform an authentication.
After establishing contact between the device 13 and the apparatus within the range, they both communicate by sending successive commands and responses. Any subsequent data packet received from an external charger apparatus can then be demodulated by the load demodulator 55.
According to the disclosed embodiments, during phase I illustrated in
An advantage of the described embodiments is that they make it possible to combine, within the same circuit, RFID LF and Qi technologies.
Various embodiments and variants have been described. Those skilled in the art will understand that certain features of these embodiments can be combined and other variants will readily occur to those skilled in the art.
Finally, the practical implementation of the embodiments and variants described herein is within the capabilities of those skilled in the art based on the functional description provided hereinabove.
Device may be summarized as including a frequency demodulator (55) and an amplitude demodulator (59), the device being configured to use, in a first mode (I), both demodulators in parallel and to activate an RFID card mode or a Qi charger mode based on results provided by said demodulators.
A method implemented by a device may be summarized as including a frequency demodulator (55) and an amplitude demodulator (59), in which the device uses, in a first mode (I), both demodulators in parallel and, in a second mode (II), both demodulators successively.
Both frequency and amplitude demodulators also may include load modulators/demodulators.
In a second mode, both frequency and amplitude demodulators may operate successively.
A load modulator (57) of the device may be used when the device communicates with an external RFID A type apparatus configured in reader mode.
Said load modulator (57) may be used when the device is charged by an external apparatus and when it emulates an RFID card configured in type A.
A Qi analog front end (51) of the device may be adapted to frequency modulate or amplitude modulate data when the device is in the second mode, the frequency modulated data being used to communicate with a Qi charger device and the amplitude modulated data being used to communicate with an RFID device configured in card mode.
The demodulator in amplitude (59) may be used to demodulate a response, in load modulation, of an external A type apparatus configured in card mode.
The amplitude demodulator (59) may be used to demodulate a command received from an external apparatus configured in reader mode.
The frequency demodulator (55) may be used to demodulate a response received from an external B type apparatus configured in card mode.
The frequency demodulator (55) may be used to demodulate a digital ping or any subsequent data packet received from an external charging apparatus.
The frequency demodulator (55) may be used to demodulate a response received from an external charge apparatus.
When it detects an external field on an antenna, may check whether that field comes from an RFID apparatus or from a Qi apparatus.
The check may be made by emitting periodic interrogation frames in RFID mode and Qi mode.
The various embodiments described above can be combined to provide further embodiments. These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.
Number | Date | Country | Kind |
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2104962 | May 2021 | FR | national |