US 20100225270 A1
Exemplary embodiments are directed to wireless power. A portable chargeable device may comprise an energy storage device configured to receive power from a power source. Furthermore, the portable chargeable device may comprise a transmitter including at least one antenna and configured to transmit power stored in the energy storage device within an associated near-field region.
1. A portable chargeable device, comprising:
an energy storage device configured to receive power from a power source; and
a transmitter including at least one antenna and configured to transmit power stored in the energy storage device within an associated near-field region according to a substantially unmodulated resonant frequency.
2. The device of
3. The device of
4. The device of
5. The device of
6. The device of
7. The device of
8. The device of
9. The device of
10. A device, comprising:
a surface configured for placement of one or more electronic devices;
at least one transmit antenna proximate the surface and configured for transmitting wireless power within an associated near-field;
wherein the device is configured to:
detect a field disturbance between the transmit antenna and an antenna of an electronic device positioned thereon; and
enable one or more communication links between the one or more electronic devices positioned thereon.
11. The device of
12. The device of
13. The device of
14. The device of
15. The device of
16. A method, comprising:
receiving power with an energy storage device within a portable chargeable device; and
transmitting power stored in the energy storage device within an associated near-field region according to a substantially unmodulated resonant frequency.
17. The method of
18. The method of
19. The method of
20. The method of
21. The method of
22. A wireless power system, the system comprising:
means for receiving power with an energy storage device within a portable chargeable device; and
means for transmitting power stored in the energy storage device within an associated near-field region according to a substantially unmodulated resonant frequency.
23. A method, comprising:
transmitting wireless power from a transmit antenna to one or more electronic devices positioned on a surface of a device according to a substantially unmodulated resonant frequency; and
conveying data from at least one electronic device of the one or more electronic devices on a display positioned on the surface of the device.
24. The method of
25. The method of
26. The method of
27. The method of
28. A wireless power system, the system comprising:
means for transmitting wireless power from a transmit antenna to one or more electronic devices positioned on a surface of a device according to a substantially unmodulated resonant frequency; and
means for conveying data from at least one electronic device of the one or more electronic devices on a display positioned on the surface of the device.
This application claims priority under 35 U.S.C. §119(e) to:
U.S. Provisional Patent Application No. 61/165,876 entitled “GENERAL WIRELESS CHARGING CONFIGURATIONS” filed on Apr. 1, 2009, the disclosure of which is hereby incorporated by reference in its entirety;
U.S. Provisional Patent Application No. 61/158,396 entitled “WIRELESS CHARGING” filed on Mar. 8, 2009, the disclosure of which is hereby incorporated by reference in its entirety; and
U.S. Provisional Patent Application No. 61/166,685 entitled “COMBINING WIRELESS CHARGING CAPABILITY AND THE ABILITY TO RECEIVE A WIRELESS CHARGE IN A SINGLE PORTABLE COMPUTING DEVICE” filed on Apr. 3, 2009, the disclosure of which is hereby incorporated by reference in its entirety.
The present invention relates generally to wireless charging, and more specifically to bidirectional charging, portable charging devices, and transmission of data between electronic devices while charging at least one of the electronic devices.
Typically, each battery powered device requires its own charger and power source, which is usually an AC power outlet. This becomes unwieldy when many devices need charging.
Approaches are being developed that use over the air power transmission between a transmitter and the device to be charged. These generally fall into two categories. One is based on the coupling of plane wave radiation (also called far-field radiation) between a transmit antenna and receive antenna on the device to be charged which collects the radiated power and rectifies it for charging the battery. Antennas are generally of resonant length in order to improve the coupling efficiency. This approach suffers from the fact that the power coupling falls off quickly with distance between the antennas. So charging over reasonable distances (e.g., >1-2 m) becomes difficult. Additionally, since the system radiates plane waves, unintentional radiation can interfere with other systems if not properly controlled through filtering.
Other approaches are based on inductive coupling between a transmit antenna embedded, for example, in a “charging” mat or surface and a receive antenna plus rectifying circuit embedded in the host device to be charged. This approach has the disadvantage that the spacing between transmit and receive antennas must be very close (e.g. mms). Though this approach does have the capability to simultaneously charge multiple devices in the same area, this area is typically small, hence the user must locate the devices to a specific area.
A need exists for wireless charging of devices while exchanging information among the devices. A need also exists for portable devices configured for receiving and transmitting power as well as bidirectional transmission of wireless power among devices.
The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.
The detailed description set forth below in connection with the appended drawings is intended as a description of exemplary embodiments of the present invention and is not intended to represent the only embodiments in which the present invention can be practiced. The term “exemplary” used throughout this description means “serving as an example, instance, or illustration,” and should not necessarily be construed as preferred or advantageous over other exemplary embodiments. The detailed description includes specific details for the purpose of providing a thorough understanding of the exemplary embodiments of the invention. It will be apparent to those skilled in the art that the exemplary embodiments of the invention may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the novelty of the exemplary embodiments presented herein.
The words “wireless power” is used herein to mean any form of energy associated with electric fields, magnetic fields, electromagnetic fields, or otherwise that is transmitted between from a transmitter to a receiver without the use of physical electromagnetic conductors.
Transmitter 104 further includes a transmit antenna 114 for providing a means for energy transmission and receiver 108 further includes a receive antenna 118 for providing a means for energy reception. The transmit and receive antennas are sized according to applications and devices to be associated therewith. As stated, an efficient energy transfer occurs by coupling a large portion of the energy in the near-field of the transmitting antenna to a receiving antenna rather than propagating most of the energy in an electromagnetic wave to the far field. When in this near-field a coupling mode may be developed between the transmit antenna 114 and the receive antenna 118. The area around the antennas 114 and 118 where this near-field coupling may occur is referred to herein as a coupling-mode region.
The receiver may include a matching circuit 132 and a rectifier and switching circuit to generate a DC power output to charge a battery 136 as shown in
As illustrated in
As stated, efficient transfer of energy between the transmitter 104 and receiver 108 occurs during matched or nearly matched resonance between the transmitter 104 and the receiver 108. However, even when resonance between the transmitter 104 and receiver 108 are not matched, energy may be transferred at a lower efficiency. Transfer of energy occurs by coupling energy from the near-field of the transmitting antenna to the receiving antenna residing in the neighborhood where this near-field is established rather than propagating the energy from the transmitting antenna into free space.
The resonant frequency of the loop or magnetic antennas is based on the inductance and capacitance. Inductance in a loop antenna is generally simply the inductance created by the loop, whereas, capacitance is generally added to the loop antenna's inductance to create a resonant structure at a desired resonant frequency. As a non-limiting example, capacitor 152 and capacitor 154 may be added to the antenna to create a resonant circuit that generates resonant signal 156. Accordingly, for larger diameter loop antennas, the size of capacitance needed to induce resonance decreases as the diameter or inductance of the loop increases. Furthermore, as the diameter of the loop or magnetic antenna increases, the efficient energy transfer area of the near-field increases. Of course, other resonant circuits are possible. As another non-limiting example, a capacitor may be placed in parallel between the two terminals of the loop antenna. In addition, those of ordinary skill in the art will recognize that for transmit antennas the resonant signal 156 may be an input to the loop antenna 150.
Exemplary embodiments of the invention include coupling power between two antennas that are in the near-fields of each other. As stated, the near-field is an area around the antenna in which electromagnetic fields exist but may not propagate or radiate away from the antenna. They are typically confined to a volume that is near the physical volume of the antenna. In the exemplary embodiments of the invention, magnetic type antennas such as single and multi-turn loop antennas are used for both transmit (Tx) and receive (Rx) antenna systems since magnetic near-field amplitudes tend to be higher for magnetic type antennas in comparison to the electric near-fields of an electric-type antenna (e.g., a small dipole). This allows for potentially higher coupling between the pair. Furthermore, “electric” antennas (e.g., dipoles and monopoles) or a combination of magnetic and electric antennas is also contemplated.
The Tx antenna can be operated at a frequency that is low enough and with an antenna size that is large enough to achieve good coupling (e.g., >−4 dB) to a small Rx antenna at significantly larger distances than allowed by far field and inductive approaches mentioned earlier. If the Tx antenna is sized correctly, high coupling levels (e.g., −2 to −4 dB) can be achieved when the Rx antenna on a host device is placed within a coupling-mode region (i.e., in the near-field) of the driven Tx loop antenna.
Exemplary embodiments of the invention include electronic devices configured for both receiving and transmitting wireless power. As such, various exemplary embodiments are directed to bidirectional wireless power transmission. Further, according to various exemplary embodiments, electronic devices may be configured to at least one of receive and transmit wireless power while simultaneously exchanging data with at least one other electronic device. Moreover, exemplary embodiments include a charging system having a base station charger coupled to a power source and configured for charging one or more portable charging pads.
More specifically, transmit antenna 404 may be configured to receive power, via a transmitter (e.g., transmitter 104 of
It is noted that transmit antenna 404 may be configured to simultaneously transmit power to one or more antennas within a near-field of transmit antenna 404. Moreover, although charging system 400 includes only one transmit antenna coupled to charging device 402 and two chargeable devices positioned proximate thereto, embodiments of the present invention are not so limited. Rather, a charging system including a charging device having any number of transmit antennas coupled thereto and any number of chargeable devices positioned proximate thereto is within the scope of the present invention.
Furthermore, in accordance with an exemplary embodiment, first chargeable device 406 and second chargeable device 410 may each be configured for sharing data with at least one other electronic device. More specifically, as an example, first chargeable device 406 may be configured to establish a communication link with at least one other electronic device and, upon establishing the communication link, may share information (e.g., audio files, data files, or video files) with the at least one other electronic device. A communication link may be established through any known and suitable manner. For example, a communication link could be established via near-field communication (NFC) means, via reflected impedance means, via a local area network (LAN), or via a personal area network (PAN). As an example, first chargeable device 406 may be configured to establish a communication link 414 with second chargeable device 410 via any known and suitable manner and, upon establishment of communication link 414, information may be shared between first chargeable device 406 and second chargeable device 410. More specifically, after communication link 414 has been established between first chargeable device 406 and second chargeable device 410, first chargeable device 406 may transmit information to second chargeable device 410 and first chargeable device 406 may receive information from second chargeable device 410. It is noted that, initially, an electronic device (e.g., chargeable device 410 or chargeable device 406) may need to be configured to enable information sharing capabilities. However, after initial configuration, the electronic device may be indefinitely adapted for sharing information.
As a result, in accordance with one exemplary embodiment of the present invention, a chargeable device (e.g., second chargeable device 410) may be configured to receive wireless power from a transmit antenna (e.g., transmit antenna 404) and simultaneously receive information from at least one other electronic device (e.g., chargeable device 406), transmit information to at least one other electronic device (e.g., first chargeable device 406), or both. It is noted that if communication link 414 comprises a near-field communication link, a chargeable device (e.g., second chargeable device 410) may be configured to receive information from at least one other electronic device (e.g., chargeable device 406) or transmit information to at least one other electronic device (e.g., first chargeable device 406) immediately subsequent or prior to receiving wireless power from a transmit antenna (e.g., transmit antenna 404).
While wireless power transmission may occur when one device in a wireless power transmission system includes a transmitter and another device includes a receiver, a single device may include both a wireless power transmitter and a wireless power receiver. Accordingly, such an embodiment could be configured to include dedicated transmit circuitry (e.g., a transmit power conversion circuit and a transmit antenna) and dedicated receiver circuitry (e.g., a receive antenna and a receive power conversion circuit). Accordingly, the various exemplary embodiments disclosed herein identify bidirectional power transmission, namely, the capability for a device to both receive wireless power at the device and to transmit wireless power from the device.
Various benefits of such a configuration include the ability of a device to receive and store wireless power and then to subsequently transmit or “donate” stored power to another receiving or “absorbing” device. Accordingly, such a configuration may also be considered as a “peer-to-peer” “charitable” charging configuration. Such a device-charging arrangement provides considerable convenience in location under which charging occurs (i.e., the receiver or “absorbing” device need not necessarily receive a charge from an inconveniently located or unavailable charging pad).
In accordance with another embodiment of the present invention, a chargeable device having at least one antenna may be configured to transmit wireless power to at least one other chargeable device and receive wireless power from at least one other chargeable device. More specifically, with reference to
With continued reference to
At any time, first chargeable device 406 may request power from second chargeable device 410 and, in response to a power request, second chargeable device 410 may either decline or accept the request. Criteria for determining whether a power request is accepted or declined may be implementation specific and may include various factors. Such factors may include, for example only, an amount of power requested by first chargeable device 406, whether second chargeable device 410 includes a sufficient amount of energy to provide first chargeable device 406 with power, whether second chargeable device 410 is configured to source an adequate amount of current to charge first chargeable device 406, an estimated amount of time before second chargeable device 410 may receive a charge, an estimated standby time after second chargeable device 410 provides power to first chargeable device 406, or any combination thereof. Furthermore, the determination may be dependent on a user-defined preference. Moreover, a device user may receive a real-time prompt asking whether to accept or decline the power request. Upon accepting a charge request, second chargeable device 410 may wirelessly transmit power, which may be received by first chargeable device 406.
In either exemplary embodiment, the antenna configured to receive wireless power (i.e., antenna 504 or receive antenna 506) may interface with an element of electronic device 502, such as a power circuit, a battery, or any combination thereof. Accordingly, power received by antenna 504 or antenna 506 may be conveyed to the element (e.g., a battery, a power circuit, or any combination thereof) of electronic device 502. Further, the antenna configured to transmit wireless power (i.e., antenna 504 or transmit antenna 508) may interface with a power source of electronic device 502, such as a power circuit, a battery, or any combination thereof. Accordingly, power may be conveyed from the power source (e.g., a battery, a power circuit, or any combination thereof) of electronic device 502 to antenna 504 or antenna 508, which may then wirelessly transmit power within an associated near-field region.
If at any time while the electronic device is in READY to TRANSMIT ENERGY STATE 602, another electronic device configured for receiving a wireless charge is positioned within a charging region of the electronic device, an authentication process between the electronic devices may occur. After the devices have been successfully authenticated, the electronic device may transition to a “TRANSMIT STATE” 604, wherein the electronic device may transmit power to the another chargeable device. Furthermore, if at any time while the electronic device is in READY to TRANSMIT ENERGY STATE 602, the electronic device is positioned within a charging region of another electronic device configured to transmit wireless power, an authentication process between the electronic devices may occur. Upon successful authentication, the electronic device may transition to a “RECEIVE STATE” 606, wherein the electronic device may receive a wireless charge from the another electronic device. It is noted that the electronic device may be configured to simultaneously transmit wireless power and receive wireless power. Accordingly, the electronic device may simultaneously be in TRANSMIT STATE 604 and RECEIVE STATE 606.
Base station charger 652 may comprise at least one port (not shown) wherein each port is configured to receive a portable charging pad 658. It is noted that each port may be configured to mechanically couple a portable charging pad to base station charger 652, electrically couple a portable charging pad to base station charger 652, or both. Portable charging pad 658 may comprise an antenna 660 and associated circuitry 662 (see
Exemplary methods of operating a charging system (e.g., charging system 650) will now be described. One or more portable charging pads 658 may be coupled or placed proximate to base station charger 652. Base station charger 652, which may receive power via power source 654 and power connector 656, may transmit power to the one or more portable charging pads 658 via any known and suitable manner. After receiving a charge, at least one portable charging pad 658 may be removed from base station charger 652 and subsequently used for charging at least one chargeable device.
As an example, a user may charge a portable charging pad 658 via base station charger 652 positioned at a location such as a house or an office and, thereafter, remove the portable charging pad 658, and use the portable charging pad 658 to wireless charge at least one chargeable device positioned in a vehicle, such as an automobile or an airplane. As a more specific example, a user may position the portable charging pad 658 on an airplane tray table, position a media player within a charging region of the portable charging pad 658, and charge the media player while the media is in either an “off” or an “on” operational state. Accordingly, the battery life of the media player may be prolonged without a need for a wired power connection.
As another example, a user may charge a portable charging pad 658 via base station charger 652 positioned at a location in a residence, such as an office or a den. Thereafter, the user may remove the portable charging pad 658 and use the portable charging pad 658 to wireless charge at least one chargeable device at another location that may not include a power outlet. As a more specific example, a user may position the portable charging pad 658 on an outdoor table or an entry-way table that may not be proximate to a power outlet. A user may then position a laptop computer within a charging region of the portable charging pad 658 and charge the laptop computer while the laptop computer is in either an “off” or an “on” operational state. Accordingly, the battery life of the laptop computer may be prolonged without a need for a wired power connection.
As will be understood by a person having ordinary skill in the art, “surface computing” is a term associated with a technology wherein a user may interact with a computer and/or an electronic device positioned on a surface of an object (e.g., a table) through the surface of an object instead of a keyboard, mouse, or monitor. A multi-touch surface may facilitate surface computing by allowing the manipulation of objects displayed on a surface through surface contact (e.g., touch by multiple fingers or multiple users). Further, content may be transferred between two or more devices positioned on the surface of the object using a unique identifier assigned to each device.
As configured, device 500 may detect and authenticate the presence of an electronic device positioned on a surface 508 of device 500. The presence of a device, for example, a mobile phone 504 or a digital camera 506, positioned upon device 500 may be determined by detecting a field disturbance of a magnetic field established between transmitter antenna 502 and an antenna (not shown) within an electronic device (e.g., mobile phone 504) and configured for receiving wireless power. In addition to detecting the presence of an electronic device, a field disturbance may indicate that an electronic device is ready to receive wireless power, or ready to transmit or receive information. For example, an electronic device positioned on device 500, such as digital camera 506, may transmit a signal, via a wireless charging protocol, requesting a wireless charge, requesting establishment of a wireless data link, such as a Bluetooth (BT) connection, or both. It is noted that any known and suitable data link may be within the scope of the present invention. For example, a data link may comprise a Bluetooth connection, a Wi-Fi connection, a 60 GHz connection, or a UWB connection.
It is noted that before a wireless data link (e.g. a BT connection) may be established between an electronic device (e.g., mobile phone 504 or digital camera 506) and device 500, device 500 may initiate a key exchange to ‘pair’ the electronic device and device 500. Once paired, a data link may be initiated, allowing data to transfer between device 500 and the electronic device being charged. More specifically, upon establishing the data link, data, such as photographs, videos, or music, may be transferred from, for example, a ‘public’ directory of the electronic device to device 500. Furthermore, after a data link has been established and data is transferred from the electronic device to device 500, a user may interact with the data in a user-friendly, multi-touch way, while the electronic device positioned on surface 508 receives a wireless charge. As an example, data transferred from the electronic device may be conveyed (e.g., photographs may be displayed or music may be played) by device 500 while the electronic device is charging. It is noted that a device user may access and interact with data stored on the electronic device without transferring the data to device 500.
According to another exemplary embodiment, device 600 may be configured to communicate with a stand-alone computer. For example only, device 600 may be configured to communicate with a stand-alone computer via wireless means, such as via a USB adapter or a USB dongle. Accordingly, the stand-alone computer and an associated display may be used to facilitate information exchanges to and from electronic devices placed on device 600 or via the Internet. More specifically,
Those of skill in the art would understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.
Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the exemplary embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the exemplary embodiments of the invention.
The various illustrative logical blocks, modules, and circuits described in connection with the exemplary embodiments disclosed herein may be implemented or performed with a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.
The steps of a method or algorithm described in connection with the exemplary embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in Random Access Memory (RAM), flash memory, Read Only Memory (ROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.
In one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.
The previous description of the disclosed exemplary embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these exemplary embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the exemplary embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.