# Patent

## Title
Hybrid charging method for wireless power transmission based on pocket-forming

## Abstract

The present disclosure provides a hybrid charging method for wireless power transmission based on pocket-forming. This method may extend the battery life of electronic devices such as tablets, smartphones, Bluetooth headsets, smart-watches among others. The method may include wireless power transmission through suitable techniques such as pocket-forming, while including an additional source of energy (backup battery) in the receiver attached or connected to the electronic device.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 13/932,166, filed on Jul. 1, 2013, which is herein fully incorporated by reference in its entirety.


The present disclosure is related to U.S. patent application Ser. No. 13/891,430, filed May 10, 2013; U.S. patent application Ser. No. 13/891,445, filed May 10, 2013; U.S. patent application Ser. No. 13/925,469, filed Jun. 24, 2013; U.S. Non-Provisional patent application Ser. No. 14/583,625, filed Dec. 27, 2014, entitled “Receivers for Wireless Power Transmission,” U.S. Non-Provisional patent application Ser. No. 14/583,630, filed Dec. 27, 2014, entitled “Methodology for Pocket-Forming,” U.S. Non-Provisional patent application Ser. No. 14/583,634, filed Dec. 27, 2014, entitled “Transmitters for Wireless Power Transmission,” U.S. Non-Provisional patent application Ser. No. 14/583,640, filed Dec. 27, 2014, entitled “Methodology for Multiple Pocket-Forming,” U.S. Non-Provisional patent application Ser. No. 14/583,641, filed Dec. 27, 2014, entitled “Wireless Power Transmission with Selective Range,” U.S. Non-Provisional patent application Ser. No. 14/583,643, filed Dec. 27, 2014, entitled “Method for 3 Dimensional Pocket-Forming,” all of which are incorporated herein by reference in their entirety.
FIELD OF INVENTION
The present disclosure relates to wireless power transmission, and more particularly to a hybrid charging method for wireless power transmission based on pocket-forming.
BACKGROUND OF THE INVENTION
Portable electronic devices such as smart phones, tablets, notebooks and others, have become an everyday need in the way we communicate and interact with others. The frequent use of these devices may require a significant amount of power, which may easily deplete the batteries attached to these devices. Therefore, a user is frequently needed to plug in the device to a power source, and recharge such device. This may be inconvenient and troublesome if the user forgets to plug in or otherwise charge a device, the device may run out of power and be of no use to the user until the user is again able to charge the device.
Wireless power transmission may be an answer for the situation described above, however wireless power transmission may usually need a transmitter and a receiver to work. There may be situations when transmitter, being the source of power, may be out of range with the receiver and hence no wireless power transmission may occur. In some situations carrying out an extra set of batteries may be a solution, however some portable electronic devices may have internal batteries that may not be easily replaced. For the foregoing reasons, there may be a need for increasing the battery life of the aforementioned electronic devices.
SUMMARY OF THE INVENTION
The present disclosure provides a hybrid charging method for wireless power transmission based on pocket-forming. This method may extend the battery life of electronic devices such as tablets, smartphones, Bluetooth headsets, smart-watches among others running on small batteries. The method may include wireless power transmission through suitable techniques such as pocket-forming, while including an additional source of energy (backup battery) in the receiver attached or connected to the electronic device.
In an embodiment, an example of wireless power transmission through pocket forming may be provided.
In another embodiment, a schematic view of an electronic device including at least one embedded receiver with an additional feature such as a backup battery, may be provided.
In an even further embodiment, an example where wireless power transmission may occur may be provided. In this example, a tablet device, including an embedded or connected receiver with a backup battery, may be charged.
In another embodiment, an example where wireless power transmission may not occur may be provided. In this example, a tablet device, including an embedded or connected receiver with a backup battery, may be out of range with a transmitter and hence no wireless power transmission may occur. However, the tablet device, when running out of power, may use an alternative source of power such as the backup battery included in the embedded receiver.
The method here disclosed may provide wireless power to electronic devices such as tablets, smartphones and the like. As described in embodiments above, such devices may include an additional source of power such as a backup battery which may be included in the receiver attached to them, which upon discharge may power fully and/or partially the aforementioned devices. The foregoing method may decrease fully and/or partially power loads on a device's battery. Thus, battery life in such devices may be enhanced.



BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present disclosure are described by way of example with reference to the accompanying figures, which are schematic and may not be drawn to scale. Unless indicated as representing prior art, the figures represent aspects of the present disclosure. The main features and advantages of the present disclosure will be better understood with the following descriptions, claims, and drawings, where:
FIG. 1 illustrates a wireless power transmission example situation using pocket-forming, according to an embodiment.
FIG. 2 illustrates prior art powering of an electronic device.
FIG. 3 illustrates an electronic device including at least one embedded which may contain a backup battery, according to an embodiment.
FIGS. 4A and 4B show an example where the embodiment described in FIG. 3 may be of use. In this example wireless power transmission may or may not occur.



DETAILED DESCRIPTION
“Pocket-forming” may refer to generating two or more RF waves which converge in 3-d space, forming controlled constructive and destructive interference patterns.
“Pockets of energy” may refer to areas or regions of space where energy or power may accumulate in the form of constructive interference patterns of RF waves.
“Null-space” may refer to areas or regions of space where pockets of energy do not form because of destructive interference patterns of RF waves.
“Transmitter” may refer to a device, including a chip which may generate two or more RF signals, at least one RF signal being phase shifted and gain adjusted with respect to other RF signals, substantially all of which pass through one or more RF antenna such that focused RF signals are directed to a target.
“Receiver” may refer to a device including at least one antenna element, at least one rectifying circuit and at least one power converter, which may utilize pockets of energy for powering, or charging an electronic device.
“Adaptive pocket-forming” may refer to dynamically adjusting pocket-forming to regulate power on one or more targeted receivers.
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, which may not be to scale or to proportion, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings and claims, are not meant to be limiting. Other embodiments may be used and/or and other changes may be made without departing from the spirit or scope of the present disclosure.
FIG. 1 illustrates wireless power transmission 100 using pocket-forming. A transmitter 102 may transmit controlled Radio RF waves 104 which may converge in 3-d space. These Radio frequencies (RF) waves 104 may be controlled through phase and/or relative amplitude adjustments to form constructive and destructive interference patterns (pocket-forming). Pockets of energy 108 may be formed at constructive interference patterns and can be 3-dimensional in shape whereas null-spaces may be generated at destructive interference patterns. A receiver 106 may then utilize pockets of energy 108 produced by pocket-forming for charging or powering an electronic device, for example a laptop computer 110 and thus effectively providing wireless power transmission. In other situations there can be multiple transmitters 102 and/or multiple receivers 106 for powering various electronic equipment for example smartphones, tablets, music players, toys and others at the same time. In other embodiments, adaptive pocket-forming may be used to regulate power on electronic devices.
In an embodiment, transmitter 102 may include a housing where at least two or more antenna elements, at least one RF integrated circuit (RFIC), at least one digital signal processor (DSP) or micro-controller, and one communications component may be included. Transmitter 102 may also include a local oscillator chip for converting alternating current (AC) power to analog RF signals. Such RF signals may firstly be phase and gain adjusted through an RFIC proprietary chip, and then converted to RF waves via antenna elements. On the other hand, receiver 106 may include a housing where at least one antenna element, at least one rectifier and at least one power converter may be included. Receiver 106 may communicate with transmitter 102 through short RF waves or pilot signals sent through antenna elements. In some embodiments, receiver 106 may include an optional communications device for communicating on standard wireless communication protocols such as Bluetooth, Wi-Fi or Zigbee with transmitter 102. In some embodiments, receiver 106 may be implemented externally to electronic devices in the form of cases, e.g. camera cases, phone cases and the like which may connect trough suitable and well known in the art techniques such as universal serial bus (USB). In other embodiments, receiver 106 may be embedded within electronic devices.
FIG. 2 illustrates prior art powering of an electronic device 200. Electronic device 200 may require a power supply 202 for powering its various components, for example a communications device 204 for wireless communication, a micro-controller 206 for function control, among other components not shown in FIG. 2. In an embodiment, electronic device 200 may represent a tablet running on power supply 202 in the form of a Lithium-ion battery or any of the like.
Power supply 202 may be the only power source on which electronic device 200 may run. Thus, when power supply 202 runs out, electronic device 200 may be unusable. The foregoing situation may be unpleasant to users who may depend heavily on their electronic devices and may therefore be forced to carry extra power supplies 202 in the form of batteries for example. In addition, if electronic device 200 does not allow for charging or replacing power supply 202, electronic device 200 may be inoperable, and thus, may turn into unnecessary waste.
FIG. 3 illustrates an electronic device 300, similar to electronic device 200 described in FIG. 2. Electronic device 300 may include at least one embedded receiver 302, that may have a backup battery 310 as an additional feature compared to the one described in FIG. 1. Embedded receiver 302, may also include a subset of antenna elements 304 for converting pockets of energy, produced through pocket-forming, into AC voltage, at least one rectifier 306 where AC voltage may be converted to direct current (DC) voltage, and at least one power converter 308 for providing constant DC voltage output to either a backup battery 310 or to power supply 202.
In this embodiment, backup battery 310 may be an additional source of energy for electronic device 300 and may be any suitable battery that provides enough voltage to power or charge electronic device 300. Backup battery 310 may also require a power converter 312 to deliver DC voltage to power supply 202. Backup battery 310 may be charged while embedded receiver 302 is capturing pockets of energy from the transmitter to which is connected. In other embodiments, power converter 308 may pass DC voltage directly to power supply 202 without charging backup battery 310. In yet another embodiment power converter 308 may pass DC voltage to both power supply 202 and backup battery 310 at the same time. Power supply 202 may constantly provide DC voltage to micro-controller 206 and communications device 204 as long as it does not run out of charge or power from embedded receiver 302.
FIGS. 4A and 4B illustrate two embodiments where wireless power transmission 400 may or may not occur. In FIG. 4A, an user 402 may be inside a room and may hold on his hands an electronic device, which in this case, may be a tablet 404. Tablet 404 may include a receiver (not shown) either embedded to it or as a separate adapter connected to tablet 404. The receiver embedded or connected to tablet 404 may be as the one described in FIG. 3, hence including an additional feature such as a backup battery (not shown). The backup battery included in the receiver may be fully or partially charged while wireless power transmission takes place. FIG. 4A also shows a transmitter 406, as the one described in FIG. 1. Transmitter 406 may transmit controlled Radio RF waves 408 which may converge in 3-d space and deliver pockets of energy 410 to the receiver. In this embodiment, the receiver may either power tablet 404 directly or charge backup battery first and then power tablet 404.
FIG. 4B shows an example where wireless power transmission may not occur. In this embodiment, user 402 may be found outdoors walking down the sidewalk where transmitter 406 may not be available, and hence no wireless power transmission may occur. However, tablet 404 may still have an extra source of power (backup battery 310) included as an internal part of the receiver. As described in FIG. 4A, backup battery 310 may have been charged while transmitter 406 was available. Tablet 404 may then use the available power from the backup battery 310 in the receiver when power supply 202 (tablet 404's battery) runs out. Thus, power supply 202 life can be greatly increased.
While various aspects and embodiments have been disclosed herein, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

## Claims

1. A method for wireless power charging, the method comprising:
when a receiver coupled to an electronic device is within a threshold distance from a transmitter:
receiving, by at least one antenna of the receiver, a plurality of wireless power transmission waves transmitted by the transmitter, wherein the plurality of wireless power transmission waves constructively interferes at the receiver;
converting, by the at least one antenna of the receiver, the plurality of wireless power transmission waves that constructively interfere at the receiver into an alternating current (AC) voltage;
rectifying, by a rectifier of the receiver, the AC voltage to a direct current (DC) voltage, wherein the rectifier is coupled to the at least one antenna;
converting, by a power converter of the receiver, the DC voltage to a constant DC voltage output, wherein the power converter is coupled to the rectifier; and
providing, by the power converter of the receiver, the constant DC voltage output to a backup battery of the receiver to at least partially charge the backup battery, wherein the power converter is coupled to the backup battery; and

when the receiver is not within the threshold distance from the transmitter, and after providing the constant DC voltage output to the backup battery to at least partially charge the backup battery, draining the backup battery to provide power to a battery of the electronic device.

2. The method of claim 1, wherein the receiver is embedded in the electronic device.

3. The method of claim 1, wherein a controller of the electronic device is coupled to a communication device of the electronic device and the battery of the electronic device, wherein the controller is configured to communicate with the transmitter via the communication device in order to control energy received by the at least one of the backup battery and the battery of the electronic device.

4. The method of claim 1, wherein the power converter is directly coupled to the backup battery and the battery of the electronic device.

5. The method of claim 1, wherein an additional power converter is electrically interposed between the backup battery and the battery of the electronic device, the additional power converter delivery DC voltage from the backup battery and to the battery of the electronic device.

6. The method of claim 1, wherein the backup battery is coupled to the battery of the electronic device.

7. The method of claim 1, wherein a case comprises the receiver, wherein the case encases the electronic device, wherein the case is electrically coupled to the electronic device via at least one of a bus and a plug so that the receiver provides power to the electronic device.

8. The method of claim 1, wherein:
the battery of the electronic device comprises a rechargeable Lithium-ion battery,
the battery of the electronic device is coupled to a controller external to the receiver, and
the controller comprises at least one of a digital signal processor, a microprocessor and an application specific integrated circuit (ASIC).

9. The method of claim 1, further comprising, when the receiver is within the threshold distance from the transmitter:
providing, by the power converter of the receiver, the constant DC voltage output to the battery of the electronic device while at least partially charging the backup battery.

10. The method of claim 1, wherein the plurality of wireless power transmission waves converge at the receiver to define a pocket of energy.

11. The method of claim 1, wherein the power converter maintains a first power level to charge the battery of the electronic device and a second power level to charge the backup battery.

12. The method of claim 1, wherein:
the power converter is a first power converter,
the first power converter is also coupled to the battery of the electronic device, and
a second power converter of the receiver is electrically interposed between the backup battery and the battery of the electronic device to deliver DC voltage from the backup battery to the battery of the electronic device.

13. The method of claim 1, further comprising, when the receiver is within the threshold distance from the transmitter:
communicating a first power status of the backup battery and a second power status of the battery of the electronic device to the transmitter; and
receiving at least one wireless power transmission wave from the transmitter that is changed based on the communicating.

14. The method of claim 1, wherein draining the backup battery to provide power to the battery of the electronic device is performed in response to the battery of the electronic device being drained.

15. A wireless power receiving system, the system comprising:
an electronic device comprising a controller and a battery;
a receiver coupled to the electronic device, the receiver comprising:
an antenna configured to, when the receiver is within a threshold distance from a transmitter:
receive a plurality of wireless power transmission waves transmitted by the transmitter, wherein the plurality of wireless power transmission waves constructively interfere at the receiver, and
convert the plurality of wireless power transmission waves that constructively interfere at the receiver into an alternating current (AC) voltage;

a rectifier coupled to the antenna, wherein the rectifier is configured to rectify the AC voltage into a DC voltage;
a power converter configured to convert the DC voltage into a constant DC voltage, wherein the power converter is configured to charge a backup battery of the receiver and the battery of the electronic device external to the receiver based on the constant DC voltage;
the backup battery coupled to the power converter, wherein the backup battery is configured to receive the constant DC voltage from the power converter, wherein the constant DC voltage is sufficient to charge the backup battery;

wherein the controller is configured to, when the receiver is not within the threshold distance from the transmitter, and after the backup battery receives the constant DC voltage to at least partially charge the backup battery, drain the backup battery to provide power to the battery of the electronic device.

16. The system of claim 15, wherein the receiver is configured to communicate with the transmitter through at least one of a short RF wave and a pilot signal sent through the antenna.

17. The system of claim 15, wherein the battery of the electronic device is a chargeable lithium battery.

18. The system of claim 15, wherein the receiver is embedded in the electronic device.

19. The system of claim 15, wherein the power converter is configured to charge the backup battery first and then charge the battery of the electronic device.

20. A receiver coupled to an electronic device, the receiver comprising:
at least one antenna configured to, when the receiver is within a threshold distance from a transmitter:
receive a plurality of wireless power transmission waves transmitted by the transmitter, wherein the plurality of wireless power transmission waves constructively interferes at the receiver, and
convert the plurality of wireless power transmission waves that constructively interfere at the receiver into an alternating current (AC) voltage;

a rectifier coupled to the at least one antenna, wherein the rectifier is configured to rectify the AC voltage into a DC voltage; and
a power converter configured to:
convert the DC voltage into a constant DC voltage output, and
provide the constant DC voltage output to a backup battery of the receiver,

wherein the backup battery, after receiving at least a partial charge, is drained to provide power to a battery of the electronic device when the receiver is not within the threshold distance from the transmitter.