Apparatus for power wireless transfer between two devices and simultaneous data transfer

• US 8,941,353 B2
• Filed: 06/30/2011
• Issued: 01/27/2015
• Est. Priority Date: 06/30/2010
• Status: Active Grant

• Current Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Inventors: Di Guardo, Mario
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): BOATENG, ALEXIS ASIEDUA
• Application Number:
  US13/174,021
• Publication Number:
  US 20120001593A1
• Time in Patent Office: 1,307 Days
• Field of Search: 320/104, 320/108, 320/112, 320/114, 320/115, 307/104
• US Class Current: 320/108
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H04L 27/10 Frequency-modulated carrier systems, i.e. using frequency-shift keying H04L27/32 takes precedence
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex

Abstract

A system for the wireless transfer of power includes a first device connected to a power supply source and provided with a first resonant circuit at a first frequency, a second device comprising at least one battery, provided with a second resonant circuit at said first frequency, arranged at a distance smaller than the wavelength associated with said first frequency and not provided with wires for the electrical connection with said first device. The first device is adapted to transfer a first signal representing the power to be sent to the second device for charging said at least one battery and comprises means adapted to modulate the frequency of said first signal for transferring data from the first device to the second device simultaneously with the power transfer. The second device comprises means adapted to demodulate the received signal, corresponding to the first signal sent from the first device, to obtain the transmitted data.

Claims

1. An apparatus, comprising:

a battery;

a first resonant circuit configured to resonate at a first frequency, the first resonant circuit including a first coil and being configured to wirelessly receive a first signal having a power configured to charge said battery and including data;

a second resonant circuit configured to resonate at a second frequency, the second resonant circuit including a second coil and being configured to wireless transmit a second signal;

a demodulator configured to demodulate the first signal to obtain the transmitted data and charge the battery with the power from the first signal; and

a modulator configured to modulate the second frequency of said second signal for transferring data externally, wherein the first and second resonant circuits, the demodulator, and the modulator are configured to provide full-duplex communication with external devices, wherein said modulator is configured to modulate said second signal by setting a frequency deviation by a determined quantity from said second frequency, said determined quantity being such as to prevent oscillation of the second resonant circuit from occurring outside a bell-shaped resonant curve centered on said second frequency and such as to prevent a frequency of the oscillation from being outside bandwidth of the second resonant circuit.

2. The apparatus according to claim 1, wherein said modulator is configured to provide a first logic value corresponding to a deviation of the oscillation frequency from the second frequency by said determined quantity and is configured to provide a second logic value corresponding to a lack of oscillation deviation from said second frequency.

3. The apparatus according to claim 1, wherein said second frequency has a different value than the first frequency such as to ensure that no interference exists between a radiation field at the first frequency and a radiation field at the second frequency.

4. The apparatus according to claim 1, wherein said second signal has a reduced power content such as to obtain a signal/noise ratio higher than 20 decibels.

5. The apparatus according to claim 1, wherein said second frequency is lower than one-fourth of the first frequency.

6. A system for wirelessly transferring power, comprising:

a first apparatus that includes;

a battery;

a first resonant circuit configured to resonate at a first frequency, the first resonant circuit including a first coil and being configured to wirelessly receive a first signal having a power configured to charge said battery and including data;

a second resonant circuit configured to resonate at a second frequency, the second resonant circuit including a second coil and being configured to wireless transmit a second signal;

a first demodulator configured to demodulate the first signal to obtain the transmitted data and charge the battery with the power from the first signal; and

a first modulator configured to modulate the second frequency of said second signal for transferring data externally, wherein the first and second resonant circuits, the first demodulator, and the first modulator are configured to provide full-duplex communication with external devices; and

a second apparatus including;

a third resonant circuit configured to resonate at the first frequency, the third resonant circuit including a third coil and being configured to wirelessly transmit the first signal to the first device;

a fourth resonant circuit configured to resonate at the second frequency, the fourth resonant circuit including a fourth coil and being configured to wirelessly receive the second signal;

a second modulator configured to modulate the frequency of said first signal; and

a second demodulator configured to demodulate the second signal from said second device, wherein the third and fourth resonant circuits, the second demodulator, and the second modulator are configured to provide full-duplex communication with the first apparatus, wherein said first modulator is configured to modulate said second signal by setting a frequency deviation by a first quantity from said second frequency, said first quantity being such, as to prevent oscillation of the second resonant circuit from occurring outside a bell-shaped resonant curve centered on said second frequency and such as to prevent a frequency of the oscillation from being outside a bandwidth of the second resonant circuit.

7. The system according to claim 6, wherein the first modulator is configured to provide a first logic value corresponding to a deviation of the oscillation frequency from the second frequency by said determined quantity and is configured to provide a second logic value corresponding to a lack of oscillation deviation from said second frequency.

8. The system according to claim 6, wherein said second modulator is configured to modulate said first signal by setting a frequency deviation by a second quantity from first second frequency, said second quantity being such as to prevent oscillation of the first resonant circuit from occurring outside a bell-shaped resonant curve centered on said first frequency and such as to prevent a frequency of the oscillation from being outside a bandwidth of the first resonant circuit.

9. The system according to claim 8, wherein the second modulator is configured to provide a first logic value corresponding to a deviation of the oscillation frequency from the first frequency by said second quantity and is configured to provide a second logic value corresponding to a lack of oscillation deviation from said first frequency.

10. The system according to claim 6, wherein said second frequency has a different value than the first frequency such as to ensure that no interference exists between a radiation field at the first frequency and a radiation field at the second frequency.

11. The system according to claim 6, wherein said second signal has a reduced power content such as to obtain a signal/noise ratio higher than 20 decibels.

12. The system according to claim 6, wherein said second frequency is lower than one-fourth of the first frequency.

13. A method, comprising:

provide full-duplex communication between an apparatus and external devices, the apparatus including first and second resonant circuits, a demodulator, and a modulator that are configured to provide the full-duplex communication with the external devices, the providing including;

wirelessly receiving, using the first resonant circuit, a first signal having a power configured to charge a battery and including data, the first resonant circuit being configured to resonate at a first frequency and including a first coil;

wirelessly transmitting a second signal using the second resonant circuit, which is configured to resonate at a second frequency and includes a second coil;

demodulating, using the demodulator, the first signal to obtain the transmitted data and charge the battery with the power from the first signal; and

modulating, using the modulator, the second frequency of said second signal for transferring data externally, wherein said modulator modulates said second signal by setting a frequency deviation by a determined quantity from said second frequency, said determined quantity being such as to prevent oscillation of the second resonant circuit from occurring outside a bell-shaped resonant curve centered on said second frequency and such as to prevent a frequency of the oscillation from being outside a bandwidth of the second resonant circuit.

14. The method according to claim 13, wherein said modulator provides a first logic value corresponding to a deviation of the oscillation frequency from the second frequency by said determined quantity and provides a second logic value corresponding to a lack of oscillation deviation from said second frequency.

15. The method according to claim 13, wherein said second frequency has a different value than the first frequency such as to ensure that no interference exists between a radiation field at the first frequency and a radiation field at the second frequency.

16. The method according to claim 13, wherein said second signal has a reduced power content such as to obtain a signal/noise ratio higher than 20 decibels.

17. The method according to claim 13, wherein said second frequency is lower than one-fourth of the first frequency.