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US 11,888,550 B2Granted
Antenna including an NFC coil and a power coil that are magnetically coupled together
AssigneeSTMicroelectronics (Rousset) SAS
InventorHugues Creusy
Life of this patent
Estimating the term…
Abstract
An antenna configured for near field communication includes a first coil for transmitting and receiving signals having a first frequency and a second coil for transmitting and receiving signals having a second frequency greater than at least twice the first frequency. The first and second coils are magnetically coupled with a coupling coefficient greater than 0.5.
Claims18
A near field communications receiver device, comprising:
- receiver circuitry;
- wherein said receiver circuitry comprises a power receiving circuit and a data communications receiving circuit;
- and
- an antenna coupled to the receiver circuitry and configured to receive a signal having a first frequency;
- wherein said antenna comprises:
- a first coil electrically connected to the power receiving circuit but not to the data communications receiving circuit, and where a resonant frequency of a circuit formed by the first coil and the power receiving circuit is equal to the first frequency;
- and
- a second coil electrically connected to the data communications receiving circuit but not to the power receiving circuit, and where a resonant frequency of a circuit formed by the second coil and the data communications receiving circuit is equal to a second frequency greater than at least twice the first frequency when the power receiving circuit is activated and is equal to the first frequency when the power receiving circuit is deactivated;
- wherein the first and second coils are magnetically coupled with a coupling coefficient greater than 0.5;
- wherein the circuitry is configured, in a first operating phase to receive data for transfer to the data communications receiving circuit, to deactivate the power receiving circuit to produce an increased impedance of the power receiving circuit and cause, through the magnetic coupling of the first and second coils, a change in impedance of the second coil so that the second coil is configured to receive signals at the first frequency;
- and
- wherein the circuit is further configured, in a second operating phase to receive power for transfer to the power receiving circuit, to activate the power receiving circuit to produce a decreased impedance of the power receiving circuit.
9 more elements
A near field communications (NFC) receiver, comprising:
- a first antenna tuned to an NFC communications frequency;
- a second antenna tuned to a further frequency that is at least two times said NFC communications frequency;
- wherein the first antenna and the second antenna are magnetically coupled with a coupling coefficient greater than 0.5;
- a power receiving circuit electrically connected to the first antenna, but not the second antenna, where a resonant frequency of a circuit formed by the first antenna and the power receiving circuit is equal to the NFC communications frequency in a second operating phase for the NFC receiver to receive power for transfer to the power receiving circuit;
- and
- an NFC data communications circuit electrically connected to the second antenna, but not the first antenna, where a resonant frequency of a circuit formed by the second antenna and the NFC data communications circuit is equal to the further frequency in the second operating phase and is equal to the NFC communications frequency in a first operating phase for the NFC receiver to receive data for transfer to the NFC data communications circuit;
- wherein, in the first operating phase, the power receiving circuit is deactivated to produce an increased impedance of the power receiving circuit, the increase impedance causing, through the magnetic coupling of the first antenna and second antenna, an increase in an inductance of the second antenna so that the second antenna is configured to receive data transfer signals at the NFC communications frequency.
4 more elements
Dependencies are inferred from the claim text.