Flat antennas having two or more resonant frequencies for use in wireless power transmission systems
The various embodiments described herein include methods, devices, and systems for wireless power transmission. In one aspect, a wireless power transmission system includes an antenna component configured to transmit and/or receive electromagnetic waves, such as power waves, the antenna component having at least two conductive plates positioned on a same plane, where: (1) the at least two conductive plates form a monopole antenna configured to transmit and/or receive electromagnetic waves in a first frequency range, (2) the at least two conductive plates are positioned such that a gap exists between the at least two conductive plates, thereby forming a capacitor, and (3) the at least two conductive plates and the gap form a loop antenna configured to transmit and/or receive electromagnetic waves in a second frequency range.
1. A transmitter device for a wireless charging system, comprising:
an antenna component configured to transmit electromagnetic waves toward a wireless power receiver, the antenna component having at least two conductive plates positioned on a same plane and a feed line between the at least two conductive plates, wherein:
one of the at least two conductive plates and the feed line form a monopole antenna configured to transmit electromagnetic waves in a first frequency range, wherein the feed line and the two conductive plates extend in the same plane and the feed line is perpendicular to an edge of the one of the at least two conductive plates within the same plane,
the at least two conductive plates are positioned such that a gap exists between the at least two conductive plates, thereby forming a capacitor, and
the at least two conductive plates, the feed line, and the capacitor form a loop antenna configured to transmit electromagnetic waves in a second frequency range;
an integrated circuit configured to control operation of the antenna; and
a transmission line coupling the antenna to the integrated circuit.
2. The transmitter device of claim 1 , wherein the first frequency range and the second frequency range are distinct frequency ranges.
3. The transmitter device of claim 2 , wherein the first frequency range includes a frequency of 900 MHz or a frequency of 5.8 GHz.
4. The transmitter device of claim 3 , wherein the second frequency range includes a frequency of 2.4 GHz.
5. The transmitter device of claim 1 , wherein the antenna component is configured to concurrently transmit electromagnetic waves in the first frequency range and in the second frequency range.
6. The transmitter device of claim 1 , wherein the antenna component is configured to receive communication signals from the wireless power receiver using at least one of the first frequency range and the second frequency range.
7. The transmitter device of claim 6 , wherein the antenna component is configured to receive the communication signals while the antenna component is transmitting electromagnetic waves.
8. The transmitter device of claim 6 , wherein:
the communication signals received from the wireless power receiver include information identifying an amount of power received by the wireless power receiver, and
the transmitter device adjusts one or more transmission characteristics used to transmit electromagnetic waves to increase an amount of power received by the wireless power receiver.
9. The transmitter device of claim 1 , wherein the antenna component has a two-dimensional structure and does not include vias that extend outside of the same plane on which the at least two conductive plates are positioned.
10. The transmitter device of claim 1 , wherein the antenna component further includes an additional loop antenna configured to transmit in a third frequency range, distinct from the first frequency range and the second frequency range.
11. The transmitter device of claim 1 , wherein the monopole antenna is configured to transmit communication signals at a frequency of 2.4 GHz and the loop antenna is configured to transmit power transmission signals.
12. The transmitter device of claim 1 , wherein the monopole antenna is configured to transmit power transmission signals and the loop antenna is configured to transmit communication signals at a frequency of 2.4 GHz.
13. The transmitter device of claim 1 , wherein the monopole antenna and the loop antenna are configured to transmit electromagnetic waves toward the wireless power receiver.
14. The transmitter device of claim 1 , wherein at least one of the monopole antenna and the loop antenna is tunable to adjust a corresponding transmit frequency.
15. The transmitter device of claim 1 , wherein the at least two conductive plates each have a distinct geometric or irregular shape.
16. The transmitter device of claim 1 , wherein the at least two conductive plates each have a same geometric or irregular shape.
17. The transmitter device of claim 1 , wherein the antenna component further includes a feed line coupling the at least two conductive plates.
18. The transmitter device of claim 1 , wherein at least one of the at least two conductive plates is coupled to an electrical ground.
19. The transmitter device of claim 1 , wherein the antenna component is mounted on a printed circuit board.
20. A receiver device for a wireless charging system, comprising:
an antenna component configured to receive electromagnetic waves from a wireless power transmitter, the antenna component having at least two conductive plates positioned on a same plane and a feed line between the at least two conductive plates, wherein:
one of the at least two conductive plates and the feed line form a monopole antenna configured to transmit electromagnetic waves in a first frequency range, wherein the feed line and the two conductive plates extend in the same plane and the feed line is perpendicular to an edge of the one of the at least two conductive plates within the same plane,
the at least two conductive plates are positioned such that a gap exists between the at least two conductive plates, thereby forming a capacitor, and
the at least two conductive plates, the feed line, and the capacitor form a loop antenna configured to transmit electromagnetic waves in a second frequency range;
an integrated circuit configured to control operation of the antenna and convert at least a portion of the received electromagnetic waves to an electrical current; and
a transmission line coupling the antenna to the integrated circuit.
21. The transmitter device of claim 1 , wherein a second of the at least two conductive plates is a ground plate that extends in the same plane.