Multi-frequency NFC antenna
View Patent ↗An antenna system is proposed that consists of a radiator integrated into the display of a mobile device. The antenna can be configured to service multiple frequency bands to include NFC (Near Field Communication), FM, TV, GPS, and/or Bluetooth/WiFi. When optimized for the NFC function, the display of the mobile device can be pointed in the direction of or positioned in close proximity to the NFC reader to facilitate the transaction, providing a more natural set of motions for the user. The antenna can contain multiple feed or connect points, and can contain active components to switch to or optimize for the various frequency bands.
1. An antenna system, comprising:
within a display assembly having a glass layer thereof, a conductor embedded in the glass layer of the display assembly, the glass layer forming a low-loss substrate surrounding the conductor;
the conductor being bent in a shape configured to generate an inductive field capable of coupling to an external field when connected to a receiver, transceiver, or circuit that modulates impedance.
2. The antenna system of claim 1 , wherein the conductor is optimized to resonate at the 13.56 MHz frequency band when connected or coupled to the receiver, transceiver, or circuit that modulates impedance.
3. The antenna system of claim 1 , further comprising: one or more active components, each of said one or more active components being individually coupled to a portion of the conductor; wherein the one or more active components are each configured to connect or disconnect portions of the conductor to form a continuous loop or to provide a conductor that is not connected at one end.
4. The antenna system of claim 3 , wherein said one or more active components are individually selected from: tunable capacitors, tunable inductors, diodes, and switches.
5. The antenna system of claim 3 , further comprising:
a multiport switch coupled to said conductor, said multiport switch being further coupled to two or more devices of the group consisting of: a Bluetooth receiver, TV receiver, FM receiver, and an NFC circuit; and
a CPU coupled to said multiport switch and further coupled to at least one of the one or more active components;
wherein said CPU is configured to communicate signals to the active components for actively varying a length of the conductor;
and wherein said CPU is further configured to communicate signals to the multiport switch for connecting the conductor to one of the devices.
6. The antenna system of claim 1 , wherein said conductor is configured to form at least one of: a coil, monopole, dipole, inverted F antenna (IFA), microstrip antenna, single resonance Isolated Magnetic Dipole (IMD) antenna, dual resonance IMD antenna, planar IMD antenna, or a wire.
7. The antenna system of claim 1 , further comprising: one or more active components, each of said one or more active components being individually coupled to a portion of the conductor; wherein the one or more active components are each configured to vary a reactance of the conductor to adjust a resonant frequency thereof.
8. The antenna system of claim 7 , further comprising:
a multiport switch coupled to said conductor, said multiport switch being further coupled to two or more of the group consisting of: a Bluetooth receiver, TV receiver, FM receiver, and an NFC circuit; and
a CPU coupled to said multiport switch and further coupled to at least one of the one or more active components;
wherein said CPU is configured to communicate signals to the active components for actively varying a frequency response of the conductor;
and wherein said CPU is further configured to communicate signals to the multiport switch for connecting the conductor to the respective receiver or circuit.
9. The antenna system of claim 1 , wherein said conductor is configured to form one or more of: a linear, u-shape, loop, or spiral coil antenna.
10. An multi-frequency NFC antenna system, comprising:
a conductor coupled to an active component to form a multi-frequency antenna;
said conductor being coupled to a switch, wherein said switch is adapted to couple to a plurality of devices selected from: a Bluetooth receiver, TV receiver, FM receiver, and NFC circuit; and
a CPU coupled to each of the switch and the active component via control lines extending therebetween, the CPU being configured to vary a frequency response of the conductor to achieve one of a plurality of possible frequencies thereof, and the CPU being further configured to control the switch for connecting the multi-frequency antenna to one of said devices.
11. The multi-frequency NFC antenna system of claim 10 , comprising two or more active components coupled to each of the conductor and the CPU.
12. The multi-frequency NFC antenna system of claim 10 , wherein said multi-frequency antenna comprises a first conductor portion connected to a second conductor portion at a first active component, the first and second conductor portions forming a length of the conductor.
13. The multi-frequency NFC antenna system of claim 10 , wherein said multi-frequency antenna comprises a conductor coupled to an active component selected from: a tunable capacitor, or a tunable inductor; wherein said active component is configured to vary a reactance of the conductor for altering a frequency response of the antenna.
14. The multi-frequency NFC antenna system of claim 10 , wherein said conductor is embedded in a glass layer of a display assembly, the glass layer forming a low-loss substrate surrounding the conductor.