CN115333578A

CN115333578A - Radio frequency identification and Qi wireless power device

Info

Publication number: CN115333578A
Application number: CN202210505174.8A
Authority: CN
Inventors: N·科迪尔; 甄家灏; K·布拉哈
Original assignee: Stmicroelectronics Development Co ltd; STMicroelectronics SA; STMicroelectronics Rousset SAS
Current assignee: Stmicroelectronics Development Co ltd; STMicroelectronics SA; STMicroelectronics Rousset SAS
Priority date: 2021-05-11
Filing date: 2022-05-10
Publication date: 2022-11-11

Abstract

Embodiments of the present disclosure relate to radio frequency identification and Qi wireless power devices. An apparatus is provided that includes a frequency demodulator and an amplitude demodulator. The device is configured to use a frequency demodulator and an amplitude demodulator in parallel in a first mode and to activate a Radio Frequency Identification (RFID) card mode or a Qi charger mode based on results provided by said demodulators.

Description

Radio frequency identification and Qi wireless power device

Technical Field

The present disclosure relates generally to electronic devices, and more particularly, to electronic devices that integrate RFID (radio frequency identification) technology.

Background

Contactless technology is very widespread and is widely used in transportation and access control applications. The current trend is to group as many functions as possible (traditionally carried by contactless cards or IC cards) onto a single device, such as a mobile phone.

Disclosure of Invention

There is a need for improvements in contactless access devices, particularly access devices equipped with RFID technology.

One embodiment provides an apparatus comprising a frequency demodulator and an amplitude demodulator, the apparatus being configured to use two demodulators in parallel in a first mode and to activate either the RFID card mode or the Qi charger mode based on the results provided by said demodulators.

One embodiment provides a method implemented by an apparatus comprising a frequency demodulator and an amplitude demodulator, wherein the apparatus uses two demodulators in parallel in a first mode and two demodulators in series in a second mode.

According to an embodiment, both the frequency demodulator and the amplitude demodulator further comprise a load modulator/demodulator.

According to one embodiment, in the second mode, both the frequency demodulator and the amplitude demodulator operate continuously.

According to one embodiment, the load modulator of the apparatus is used when the apparatus is communicating with an external RFID type device configured in reader mode.

According to one embodiment, the load modulator is used when the apparatus is charged by an external device and when the apparatus emulates an RFID card configured as type a.

According to an embodiment, when the apparatus is in the second mode, the Qi analog front end of the apparatus is adapted for frequency or amplitude modulated data, the frequency modulated data being for communication with the Qi charger device and the amplitude modulated data being for communication with the RFID device configured in the card mode.

According to one embodiment, an amplitude demodulator is used to demodulate the response of an external type a device configured in card mode in load modulation.

According to an embodiment, the amplitude demodulator is for demodulating commands received from an external device configured in a reader mode.

According to an embodiment, the frequency demodulator is for demodulating a response received from an external type B device configured in a card mode.

According to an embodiment, the frequency demodulator is used to demodulate a digital ping or any subsequent data packet received from the external charging device.

According to an embodiment, the frequency demodulator is for demodulating a response received from the external charging device.

According to one embodiment, when an external field is detected on the antenna, it is checked whether the field is from an RFID device or from a Qi device.

According to an embodiment, the check is performed by transmitting periodic interrogation frames in the RFID mode and the Qi mode.

Drawings

The above features and advantages, and others, will be described in detail in the following description of particular embodiments, given by way of illustration and not limitation with reference to the accompanying drawings, in which:

fig. 1 schematically shows an example of a communication system comprising a device of the Qi technique, to which the embodiments are applicable as an example;

FIG. 2 shows a timing diagram of the mode of operation of the apparatus of FIG. 1;

FIG. 3 shows a flow chart illustrating a portion of the timing diagram shown in FIG. 2;

FIG. 4 illustrates an example of a portion of the timing diagram shown in FIG. 2;

FIG. 5 shows a block diagram of an embodiment of a communication circuit of the apparatus shown in FIG. 1;

FIG. 6 illustrates a first example of operation of the circuit shown in FIG. 5;

FIG. 7 illustrates another example of a portion of the timing diagram shown in FIG. 2;

FIG. 8 illustrates a second example of operation of the circuit shown in FIG. 5;

FIG. 9 illustrates another example of a portion of the timing diagram shown in FIG. 2;

FIG. 10 illustrates a third example of operation of the circuit shown in FIG. 5;

FIG. 11 illustrates a fourth example of operation of the circuit shown in FIG. 5;

FIG. 12 shows a fifth operational example of the circuit shown in FIG. 5;

FIG. 13 shows a sixth operational example of the circuit shown in FIG. 5; and

fig. 14 shows another partial example of the timing chart shown in fig. 2.

Detailed Description

Similar features have been designated by similar reference numerals in the various figures. In particular, structural and/or functional features common to various embodiments may have the same reference numerals, and may have the same structural, dimensional, and material characteristics.

For the sake of clarity, only the operations and elements that are helpful in understanding the embodiments described herein have been illustrated and described in detail. Specifically, the circuits determined according to their respective functions are not structurally detailed.

Unless otherwise stated, when two elements are referred to as being connected together, this means being directly connected, without any intervening elements other than conductors; when two elements coupled together are referred to, this means that the two elements may be connected, or may be coupled through one or more other elements.

In the following disclosure, unless otherwise indicated, when absolute positional qualifiers, such as the terms "front", "back", "upper", "lower", "left", "right", etc., or relative positional qualifiers, such as the terms "upper", "lower", "high", "low", etc., or orientation qualifiers, such as "horizontal", "vertical", etc., are referred to the directions shown in the figures.

Unless otherwise specified, the expressions "about", "approximately", "substantially" and "in the range of\8230A, and magnitude" are expressed to within 10%, preferably within 5%.

In this description it is proposed to exploit the fact that the Qi technology (corresponding to the standard developed by the wireless power consortium for wireless energy transfer) is widely exploited in new smart phones. The Qi technique is particularly interesting because it is applicable to frequency bands including Low Frequencies (LF) (100 kHz to 200 kHz). Therefore, in this description, the establishment of LF communication by RFID technology is sought by using some components of the circuit dedicated to the Qi technology.

Fig. 1 schematically shows an example of a communication system of a device comprising the Qi technique, as an example, the disclosed embodiments are applicable to the Qi technique.

The system 11 shown in fig. 1 comprises an electronic device 13, which electronic device 13 is adapted to communicate with other electronic devices/apparatuses using Qi technology and RFID technology.

According to one embodiment, the device 13 is a mobile phone, such as a smart phone or a tablet computer.

According to the embodiment shown in fig. 1, the device 13 is adapted to be charged by a Qi charger platform 15 (chargeable mode) or to charge another electronic device 17 equipped with Qi technology (charger mode). In other words, the device 13 is adapted to be adjusted according to its external environment to switch from the charger mode to the chargeable mode. The device 13 may then operate in a charger mode and charge the devices in its environment, or operate in a rechargeable mode and be charged by the charger devices in its environment.

According to the embodiment shown in fig. 1, the device 13 is further adapted to communicate with an RFID device configured in a card mode 19 and an RFID device configured in a reader mode 21. In other words, the device 13 is adapted to be adjusted according to its external environment to switch from the reader mode to the card mode. The device 13 may then operate in reader mode and communicate with devices in card mode present in its environment, or operate in card mode and communicate with devices in reader mode present in its environment.

According to an example of application, the embodiments are applicable to transportation systems and access control, for example, to doors of buildings equipped with Low Frequency (LF) technology.

Fig. 2 is a timing diagram illustrating the mode of operation of the device shown in fig. 1.

When the device 13 shown in fig. 1 is not communicating, it is in a low power mode or standby state to reduce power consumption.

When the device 13 is in a standby state, it should still be able to detect the presence of an RFID reader, an RFID card, a chargeable device or a charger device.

The timing diagram shown in fig. 2 comprises two successive portions I and II, portion I corresponding to the operation when the device 13 is in the standby mode and portion II corresponding to the operation when the device 13 is in the normal mode, called polling mode.

According to the embodiment shown in fig. 2, when the device 13 is in standby mode (part I), it "probes" its environment by means of short-duration transmit pulses 23. For example, two pulses 23 are separated by a time interval 25. The pulses 23 correspond to short field emissions of the device 13 to detect possible devices configured in card mode or chargeable devices present in the field of the device 13. In case such a device is detected, the device 13 subsequently wakes up from the standby state and switches to the normal mode (part II). This detection enables an analysis of the quantities of electricity (for example amplitude or phase) specific to these pulses 23, which can vary if a device configured in card mode or a charging device is nearby.

During interval 25, device 13 is in listener mode for devices in reader mode or charger devices within range.

Fig. 3 is a flow chart illustrating a portion of the timing diagram shown in fig. 2. More precisely, the flow chart corresponds to an implementation example of the listener mode.

If the device 13 detects a field (block 61, field detected), the device activates by exiting the standby mode (block 63, entering the active mode) and responding to the reader or charger device according to the detected technology.

More precisely, the device 13 comprises two demodulators, one adapted to demodulate on-off keying (OOK) modulation and the other adapted to demodulate frequency-shift keying (FSK) modulation. When both demodulators are active, the device 13 is in normal mode (block 65, OOK and FSK demodulator are active).

In response to the reader or charger device, the device 13 detects the device technology within range and more accurately detects the modulation type on which it is based. Thus, the device 13 detects on-off keying (OOK) modulation (block 67, OOK detected) or Frequency Shift Keying (FSK) modulation (block 73, FSK detected).

The response of the device 13 is adapted to the detected modulation type of the device.

If type a is detected on the basis of the start of the frame in addition to OOK modulation, the device 13 responds by sending an acknowledgement with load modulation according to the RFID standard (block 69 type a detected on the basis of the start of the frame: sending an acknowledgement with load modulation according to the RFID standard).

If type B is detected based on the start of the frame, in addition to OOK modulation, the device 13 also turns on the field by turning off the detection after the field and responds by modulating the response according to the RFID standard using FSK (block 71, type B detected based on the start of the frame: turning on the field after the field is turned off the detection and responding according to the RFID standard using FSK).

If FSK modulation is detected, the device 13 responds by load modulating according to the Qi standard (block 75, qi charger: responds with load modulation according to the Qi standard).

According to the embodiment shown in fig. 2, in normal mode (part II), device 13 issues periodic interrogation frames 27 during which device 13 generates a field for in-range card mode or rechargeable devices. The inquiry frame 27 may be repeated several times for any card mode device's reply before returning to standby mode. The purpose of these periodic frames (polling cycles) is to determine the type of external device based on the type of transmission frame to which the external device responds.

The frame 27 consists, for example, of two consecutive transmission bursts 29 and 31, the burst 29 (LF RFID request) being configured to produce a field understandable by the card mode device and the burst 31 (inverted Qi) being configured to produce a field understandable by the chargeable device.

In other words, during the frame 27, the device 13 consecutively implements two transmission bursts 29 and 31, each transmission burst 29 and 31 representing one type of technology (Qi or RFID). The technology types targeted by the bursts are in turn RFID technology and Qi technology.

Fig. 4 illustrates an expanded example of the portion of the timing diagram shown in fig. 2. More precisely, fig. 4 shows a timing diagram of frame 27.

According to the embodiment shown in fig. 4, burst 29 comprises a Guard time (Guard time) followed by two consecutive requests, each representing either type a or type B. Each of the first request (OOK type a command) and the second request (OOK type B command) is followed by a wait time 33 (timeout to receive a response). During the waiting time 33, the device 13 waits for a response of a type a card mode device or a type B card mode device in its field.

According to the embodiment shown in fig. 4, burst 29 and burst 31 are separated by a reset time (reset).

According to the embodiment shown in fig. 4, the burst 31 comprises a guard time (guard time) followed by a request (digital ping) representing the Qi technique. The request is followed by a wait time 33 (timeout for receiving a response). During wait time 33, device 13 waits for a response by the device to charge in its field.

According to the embodiment shown in fig. 4, device 13 is in listener mode before burst 29, between

bursts

29 and 31, and after burst 31.

According to one embodiment, each pulse 23 has a duration between 50 microseconds (μ s) and 100 μ s, for example of the order of 70 μ s, and each

pulse

29, 31 has a duration between 50 milliseconds (ms) and 100ms, for example of the order of 70 ms. The duration of interval 25 and wait time 33 is between 200ms and 1 s.

Fig. 5 schematically shows an embodiment of the communication circuit 35 of the device 13 shown in fig. 1 in the form of a block.

The communication circuit 35 is coupled to an antenna 37 (antenna) via a matching circuit 39 (matching circuit). The communication circuit 35 may also be coupled to the application processor 41 (AP) and/or the secure element 43 (SE).

According to the embodiment shown in fig. 3, the communication circuit 35 comprises:

a controller 45 (controller), for example a microcontroller or microprocessor, for managing the exchanges between the different elements of the circuit 35;

an RFID reader wireless receiver/transmitter 47 (RFID-RW-UART) coupled to the controller 45 for encoding/decoding data in a reader mode;

an RFID card analog receiver/transmitter 49 (RFID-CE-UART) coupled to the controller 45 for encoding/decoding data in card mode;

a Qi receiver/transmitter analog front end 51 (Qi receiver/transmitter analog front end) coupled to the matching circuit 39 for shaping the received and to be transmitted signals;

a transmission/transmit circuit 53 (TX driver) for amplifying the signal supplied by the controller 45 to the Qi analog front end 51 in transmission;

a frequency demodulator and load modulator/modem (also called backscatter) 55 (Qi demodulator LM/FSK), located between the Qi analog front end 51 and the controller 45, for frequency demodulating the signal received by the Qi analog front end 51;

a load modulator 57 (load modulator) between the controller 45 and the matching circuit 39 for influencing an external magnetic field in the RFID card mode or the charger mode; and

an amplitude demodulator and load modulator/demodulator 59 (RFID demodulator OOK/LM), located between the matching circuit 39 and the controller 45, is adapted to demodulate the received signals in the RFID card and reader mode, respectively.

According to an embodiment, the controller 45 comprises an encoding circuit dedicated to the Qi technique.

Fig. 6 to 14 show six examples of the operation of the circuit 35 depending on the external device it detects or the external device it detects. In each of fig. 6 to 14, components not requested in the illustrated use example are not shown.

Fig. 6 shows the circuit 35 when the device 13 detects in reader mode and communicates with a type a LF device configured in card mode.

Fig. 7 shows a timing diagram of an example of frame 27 in circuit 35 of fig. 6.

According to the embodiment shown in fig. 6 and 7, device 13 operates in reader mode when device 13 detects an external class a device configured in card mode and communicating at Low Frequency (LF).

In this mode, the application processor uses the controller 45 to run (link a) I) a low frequency RFID reader wireless application.

The controller 45 uses the RFID reader wireless receiver/transmitter 47 to construct a low frequency RFID reader wireless command or LF RFID RW command (link a) II).

The controller 45 uses the TX driver 53 and the analog front end 51 to generate the LF RFID RW command according to type a using on-off keying modulation (OOK type a command a) III, fig. 7) (link a) III).

The response from the card-mode external device to the device 13 (LM tag response, fig. 7) is demodulated using load demodulation via the RFID demodulator 59 (link a) IV).

According to an embodiment not shown, the response of the external device in card mode to the device 13 is demodulated by a Qi demodulator 55.

The controller 45 then decodes the external device with the card mode response (link a) V) using the RFID reader wireless receiver/transmitter encoder/decoder 47 and forwards the corresponding data to the application processor 41 (link a) VI).

During this operation, the controller 45 may use the secure element 43 to perform any required cryptographic operations.

After contact is established between the device 13 and the devices within range, they both communicate by sending successive commands and responses.

Fig. 8 shows the circuit 35 when the device 13 detects in reader mode and communicates with a type B LF device configured in card mode.

Fig. 9 is a timing diagram of an example of frame 27 in circuit 35 of fig. 8.

According to the embodiment shown in fig. 8, the detection of an external type B device configured in card mode is performed after no response to a request in type a.

According to the embodiment shown in fig. 8, when the device 13 detects an external type B device configured in card mode and communicating in LF, the device 13 operates in reader mode.

In this mode, the application processor uses the controller 45 to run (link b) I) a low frequency RFID reader wireless application.

The controller 45 uses the RFID reader wireless receiver/transmitter 47 to construct a low frequency RFID reader wireless command or LF RFID RW command (link b) II).

The controller 45 generates the LF RFID RW command according to type B by generating a magnetic field using the TX driver 53 and the analog front end 51 using on-off keying amplitude modulation (OOK type B command B) III, fig. 9) (link B) III).

After generating the command, the device 13 stops its magnetic field and waits for a response from the external device.

The response from the external device of the card mode to the device 13 (FSK type B response, fig. 9) is demodulated via the Qi demodulator 55 (link B) IV using frequency shift keying demodulation (FSK demodulation).

The controller 45 then decodes the external device with a card mode response (link b) V) using the RFID reader wireless receiver/transmitter 47 and forwards the corresponding data to the application processor 41 (link b) VI).

After contact is established between the device 13 and the devices within range, they all communicate by sending successive commands and responses.

Fig. 10 shows the circuit 35 when the device 13 is in the card mode to detect and communicate with a type a low frequency device configured in the reader mode.

According to the embodiment shown in fig. 10, the device 13 operates in card mode when the device 13 detects an external class a device configured in reader mode and communicating in LF.

In this mode, the application processor runs (link c) an I low frequency RFID card emulation application using controller 45.

Via the RFID demodulator 59 (link c) II), commands from the external device in reader mode to the device 13 are demodulated using on-off keying amplitude demodulation.

The controller 45 then uses the RFID card analog encoder/decoder 49 to decode the peripheral device commands (link c) III) and uses the RFID card analog encoder/decoder 49 to construct the response (link c) IV).

The controller 45 uses load modulation (link c) V) and, in the case of a device in reader mode, uses the load modulator 57 to generate a response according to type a via the matching circuit 39.

Fig. 11 shows the circuit 35 when the device 13 detects in card mode and communicates with a type B LF device configured in reader mode.

According to the embodiment shown in fig. 11, when the device 13 detects an external type B device configured in reader mode and communicating in LF, the device 13 operates in card mode.

In this mode, the application processor runs (link d) I) a low frequency RFID card simulation application using the controller 45.

The command from the external device in reader mode to the device 13 is demodulated using on-off keying demodulation via the RFID demodulator 59 (link d) II).

The controller 45 then decodes the peripheral commands (link d) III) using the RFID card analog encoder/decoder 49 and constructs a response (link d) IV) using the RFID card analog encoder/decoder 49.

The controller 45 generates a response according to type B via the matching circuit 39 using frequency shift keying modulation (FSK modulation) (link d) V), using the TX driver 53 and the analog front end 51, with the device in reader mode.

During this operation, the controller 45 may use the secure element 43 to perform any cryptographic operations that may be required.

Fig. 12 shows the circuit 35 when the device 13 detects and is charged by a charger device.

According to the embodiment shown in fig. 12, the device 13 is operated in the charging mode when the device 13 detects an external charger Qi device.

In this mode, the Qi emulating ping from the external device in charger mode to the device 13 is demodulated using FSK demodulation via the Qi demodulator 55 and decoded by the controller 45 (link e) I).

The controller 45 generates a response via the matching circuit 39 (link e) II) using the load modulator 57.

The device 13 is then charging and the controller 45 transmits the monitoring data to the application processor 41 (link e) III).

During this operation, the controller 45 may use the secure element 43 if authentication needs to be performed.

Fig. 13 shows the circuit 35 when the device 13 detects and charges a chargeable device.

Fig. 14 is a timing diagram of an example of frame 27 in circuit 35 of fig. 13.

According to the embodiment shown in fig. 13 and 14, the detection of chargeable devices is performed after no response to the RFID request (frame 27).

According to the embodiment shown in fig. 13, the device 13 is operated in the charger mode when the device 13 detects an external Qi device in the charging mode.

In this mode, the controller 45 transmits a digital Qi ping I using FSK modulation (link f) I, fig. 14), using the TX driver 53.

The response from the external device (LM reply from the device to be charged, fig. 14) is demodulated by the Qi demodulator 51 (link f) II) using the load demodulator 55 and decoded by the controller (link f) III.

The device 13 then charges the devices in range and the controller 45 transmits the monitoring data to the application processor 41 (link f) III).

After contact is established between the device 13 and the devices within range, they all communicate by sending successive commands and responses. Any subsequent data packets received from the external charger device may then be demodulated by the load demodulator 55.

According to the disclosed embodiment, during phase I shown in fig. 2, the device 13 is adapted to use the Qi demodulator and the RFID demodulator in parallel, while during phase II, the device 13 is adapted to use the Qi demodulator and the RFID demodulator in sequence.

An advantage of the described embodiments is that they make it possible to combine the RFID LF and Qi techniques within the same circuit.

Various embodiments and variations have been described. Those skilled in the art will appreciate that certain features of the embodiments may be combined, and that other variations will readily occur to those skilled in the art.

Finally, the actual implementation of the embodiments and variants described herein is within the abilities of one of ordinary skill in the art based on the functional description provided above.

A device may be summarized as comprising a frequency demodulator (55) and an amplitude demodulator (59), the device being configured to use both demodulators in parallel in a first mode (I), and to activate either an RFID card mode or a Qi charger mode based on the results provided by said demodulators.

The method implemented by the device can be summarized as comprising a frequency demodulator (55) and an amplitude demodulator (59), wherein the device uses two demodulators in parallel in the first mode (I) and two demodulators in series in the second mode (II).

The frequency and amplitude demodulator may also comprise a load modulator/demodulator.

In the second mode, both the frequency demodulator and the amplitude demodulator may operate continuously.

The load modulator (57) of the device may be used when the device communicates with an external RFID device, which is configured in reader mode.

The load modulator (57) may be used when the device is charged by an external device and when it emulates an RFID card configured in type a.

When the device is in the second mode, the Qi analog front end (51) of the device may be adapted for frequency or amplitude modulated data, the frequency modulated data being used for communication with the Qi charger device, the amplitude modulated data being used for communication with the RFID device configured in the card mode.

An amplitude demodulator (59) may be used to demodulate the response of an external type a device configured in card mode in load modulation.

An amplitude demodulator (59) may be used to demodulate commands received from an external device configured in reader mode.

A frequency demodulator (55) may be used to demodulate responses received from external type B devices configured in card mode.

A frequency demodulator (55) may be used to demodulate the digital ping or any subsequent data packets received from the external charging device.

A frequency demodulator (55) may be used to demodulate responses received from the external charging device.

When the device detects an external field on the antenna, it can be checked whether the external field is from an RFID device or from a Qi device.

The check may be performed by transmitting periodic interrogation frames in the RFID mode and the 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.

Claims

1. An apparatus, comprising:

a frequency demodulator configured to provide a first demodulation result; and

an amplitude demodulator configured to provide a second demodulation result, wherein:

the apparatus is configured to:

in a first mode, the frequency demodulator and the amplitude demodulator are used in parallel; and

activating a Radio Frequency Identification (RFID) card mode or a Qi charger mode based on the first demodulation result and the second demodulation result.

2. The apparatus of claim 1, wherein the apparatus uses the frequency demodulator and the amplitude demodulator continuously in a second mode.

3. The apparatus of claim 1, wherein the frequency demodulator comprises a load modulator or demodulator and the amplitude demodulator comprises a load modulator or demodulator.

4. The apparatus of claim 1, comprising:

a load modulator, wherein the apparatus uses the load modulator in response to the apparatus communicating with an external RFID type A device configured in a reader mode.

5. The apparatus of claim 4, wherein the load modulator is responsive to the apparatus being charged by an external device and is used when the apparatus emulates an RFID card configured as type A.

6. The apparatus of claim 1, comprising:

a Qi analog front end configured to frequency modulate frequency modulated data or amplitude modulate amplitude modulated data in response to the device being in a second mode, the frequency modulated data for communication with a Qi charger device and the amplitude modulated data for communication with an RFID device configured in a card mode.

7. The apparatus of claim 1, wherein the amplitude demodulator is configured to demodulate a response of an external type-a device configured in a card mode.

8. The apparatus of claim 1, wherein the amplitude demodulator is configured to demodulate commands received from an external device configured in a reader mode.

9. The apparatus of claim 1, wherein the frequency demodulator is configured to demodulate a response received from an external type B device configured in a card mode.

10. The apparatus of claim 1, wherein the frequency demodulator is configured to demodulate a digital ping or subsequent data packet received from an external charging device.

11. The apparatus of claim 1, wherein the frequency demodulator is configured to demodulate a response received from an external charging device.

12. The apparatus of claim 1, comprising:

an antenna, wherein in response to detecting an external field on said antenna, said apparatus checks whether said field is generated by an RFID device or by a Qi device.

13. The apparatus of claim 12, wherein the apparatus checks whether the field was generated by the RFID device depending on whether a modulation type is amplitude or frequency modulated.

14. A method, comprising:

providing, by a frequency demodulator of an apparatus, a first demodulation result;

providing a second demodulation result by an amplitude demodulator of the apparatus;

in a first mode, the frequency demodulator and the amplitude demodulator are used in parallel; and is

15. The method of claim 14, comprising:

in the second mode, the frequency demodulator and the amplitude demodulator are used consecutively.

16. The method of claim 14, wherein the frequency demodulator comprises a load modulator or demodulator and the amplitude demodulator comprises a load modulator or demodulator.

17. The method of claim 14, comprising:

the load modulator is used in response to communicating with an external RFID type a device configured in a reader mode.

18. The method of claim 17, comprising:

using the load modulator in response to the apparatus being charged by an external device and in response to the apparatus emulating an RFID card configured as type A.

19. The method of claim 14, comprising:

in response to the device being in the second mode, frequency or amplitude modulated data, the frequency modulated data for communicating with a Qi charger device, the amplitude modulated data for communicating with an RFID device configured in card mode.

20. The method of claim 14, wherein the amplitude demodulator is configured to demodulate a response of an external type a device configured in a card mode.

21. The method of claim 14, wherein the amplitude demodulator is configured to demodulate commands received from an external device configured in a reader mode.

22. The method of claim 14, wherein the frequency demodulator is configured to demodulate responses received from an external type B device configured in a card mode.

23. The method of claim 14, wherein the frequency demodulator is configured to demodulate a digital ping or subsequent data packet received from an external charging device.

24. The method of claim 14, wherein the frequency demodulator is configured to demodulate a response received from an external charging device.

25. The method of claim 14, comprising:

in response to the detection of an external field on the antenna, it is checked whether the field is generated by the RFID device or by the Qi device.

26. The method of claim 25, comprising:

transmitting a periodic interrogation frame to detect whether the Qi device or the RFID device, which may be charged, is within range.

27. The method of claim 14, comprising:

when operating in the low power mode, the RFID device or Qi device is detected,

in response to detecting the RIFD device or the Qi device, transitioning to a polling mode; and

in the polling mode, it is determined whether the RIFD device or the Qi device is within range.