1. Field
The present invention relates generally to wireless charging, and more specifically to devices, systems, and methods related to wireless chargers.
2. Background
In a wired charging system or device, an electronic device may be connected to a power source, via a cord and, therefore, a charging status of the electronic device may be quickly and easily established. With wireless charging, however, there is no cord and, therefore, a charging status of an electronic device may not be known. For example, it may not be evident that an electronic device is actually receiving power or how much power is stored within the electronic device. A need exists for devices, systems, and methods related to providing information related to an electronic device while the electronic device is within a charging region of a wireless charging device.
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.
As examples, points p1, p2, p3, and p7 are all coplanar placement points for a receive antenna relative to a transmit antenna. As another example, point p5 and p6 are coaxial placement points for a receive antenna relative to a transmit antenna. The table below shows coupling strength (S21) and coupling efficiency (expressed as a percentage of power transmitted from the transmit antenna that reached the receive antenna) at the various placement points (p1-p7) illustrated in
As can be seen, the coplanar placement points p1, p2, and p3, all show relatively high coupling efficiencies. Placement point p7 is also a coplanar placement point, but is outside of the transmit loop antenna. While placement point p7 does not have a high coupling efficiency, it is clear that there is some coupling and the coupling-mode region extends beyond the perimeter of the transmit loop antenna.
Placement point p5 is coaxial with the transmit antenna and shows substantial coupling efficiency. The coupling efficiency for placement point p5 is not as high as the coupling efficiencies for the coplanar placement points. However, the coupling efficiency for placement point p5 is high enough that substantial power can be conveyed between the transmit antenna and a receive antenna in a coaxial placement.
Placement point p4 is within the circumference of the transmit antenna but at a slight distance above the plane of the transmit antenna in a position that may be referred to as an offset coaxial placement (i.e., with surface normals in substantially the same direction but at different locations) or offset coplanar (i.e., with surface normals in substantially the same direction but with planes that are offset relative to each other). From the table it can be seen that with an offset distance of 2.5 cm, placement point p4 still has relatively good coupling efficiency.
Placement point p6 illustrates a placement point outside the circumference of the transmit antenna and at a substantial distance above the plane of the transmit antenna. As can be seen from the table, placement point p7 shows little coupling efficiency between the transmit and receive antennas.
Exemplary transmit circuitry 202 includes a fixed impedance matching circuit 206 for matching the impedance of the transmit circuitry 202 (e.g., 50 ohms) to the transmit antenna 204 and a low pass filter (LPF) 208 configured to reduce harmonic emissions to levels to prevent self-jamming of devices coupled to receivers 108 (
Transmit circuitry 202 further includes a processor 214 for enabling the oscillator 212 during transmit phases (or duty cycles) for specific receivers, for adjusting the frequency of the oscillator, and for adjusting the output power level for implementing a communication protocol for interacting with neighboring devices through their attached receivers.
The transmit circuitry 202 may further include a load sensing circuit 216 for detecting the presence or absence of active receivers in the vicinity of the near-field generated by transmit antenna 204. By way of example, a load sensing circuit 216 monitors the current flowing to the power amplifier 210, which is affected by the presence or absence of active receivers in the vicinity of the near-field generated by transmit antenna 204. Detection of changes to the loading on the power amplifier 210 are monitored by processor 214 for use in determining whether to enable the oscillator 212 for transmitting energy to communicate with an active receiver.
Transmit antenna 204 may be implemented as an antenna strip with the thickness, width and metal type selected to keep resistive losses low. In a conventional implementation, the transmit antenna 204 can generally be configured for association with a larger structure such as a table, mat, lamp or other less portable configuration. Accordingly, the transmit antenna 204 generally will not need “turns” in order to be of a practical dimension. An exemplary implementation of a transmit antenna 204 may be “electrically small” (i.e., fraction of the wavelength) and tuned to resonate at lower usable frequencies by using capacitors to define the resonant frequency. In an exemplary application where the transmit antenna 204 may be larger in diameter, or length of side if a square loop, (e.g., 0.50 meters) relative to the receive antenna, the transmit antenna 204 will not necessarily need a large number of turns to obtain a reasonable capacitance.
Receive antenna 304 is tuned to resonate at the same frequency, or near the same frequency, as transmit antenna 204 (
Receive circuitry 302 provides an impedance match to the receive antenna 304. Receive circuitry 302 includes power conversion circuitry 306 for converting a received RF energy source into charging power for use by device 350. Power conversion circuitry 306 includes an RF-to-DC converter 308 and may also in include a DC-to-DC converter 310. RF-to-DC converter 308 rectifies the RF energy signal received at receive antenna 304 into a non-alternating power while DC-to-DC converter 310 converts the rectified RF energy signal into an energy potential (e.g., voltage) that is compatible with device 350. Various RF-to-DC converters are contemplated including partial and full rectifiers, regulators, bridges, doublers, as well as linear and switching converters.
Receive circuitry 302 may further include switching circuitry 312 for connecting receive antenna 304 to the power conversion circuitry 306 or alternatively for disconnecting the power conversion circuitry 306. Disconnecting receive antenna 304 from power conversion circuitry 306 not only suspends charging of device 350, but also changes the “load” as “seen” by the transmitter 200 (
When multiple receivers 300 are present in a transmitter's near-field, it may be desirable to time-multiplex the loading and unloading of one or more receivers to enable other receivers to more efficiently couple to the transmitter. A receiver may also be cloaked in order to eliminate coupling to other nearby receivers or to reduce loading on nearby transmitters. This “unloading” of a receiver is also known herein as a “cloaking” Furthermore, this switching between unloading and loading controlled by receiver 300 and detected by transmitter 200 provides a communication mechanism from receiver 300 to transmitter 200 as is explained more fully below. Additionally, a protocol can be associated with the switching which enables the sending of a message from receiver 300 to transmitter 200. By way of example, a switching speed may be on the order of 100 μsec.
In an exemplary embodiment, communication between the transmitter and the receiver refers to a device sensing and charging control mechanism, rather than conventional two-way communication. In other words, the transmitter uses on/off keying of the transmitted signal to adjust whether energy is available in the near-filed. The receivers interpret these changes in energy as a message from the transmitter. From the receiver side, the receiver uses tuning and de-tuning of the receive antenna to adjust how much power is being accepted from the near-field. The transmitter can detect this difference in power used from the near-field and interpret these changes as a message from the receiver.
Receive circuitry 302 may further include signaling detector and beacon circuitry 314 used to identify received energy fluctuations, which may correspond to informational signaling from the transmitter to the receiver. Furthermore, signaling and beacon circuitry 314 may also be used to detect the transmission of a reduced RF signal energy (i.e., a beacon signal) and to rectify the reduced RF signal energy into a nominal power for awakening either un-powered or power-depleted circuits within receive circuitry 302 in order to configure receive circuitry 302 for wireless charging.
Receive circuitry 302 further includes processor 316 for coordinating the processes of receiver 300 described herein including the control of switching circuitry 312 described herein. Cloaking of receiver 300 may also occur upon the occurrence of other events including detection of an external wired charging source (e.g., wall/USB power) providing charging power to device 350. Processor 316, in addition to controlling the cloaking of the receiver, may also monitor beacon circuitry 314 to determine a beacon state and extract messages sent from the transmitter. Processor 316 may also adjust DC-to-DC converter 310 for improved performance.
The transmit circuitry can send signals to receivers by using an ON/OFF keying process on the power amplifier 210. In other words, when the transmit modulation signal 224 is asserted, the power amplifier 210 will drive the frequency of the carrier signal 220 out on the transmit antenna 204. When the transmit modulation signal 224 is negated, the power amplifier will not drive out any frequency on the transmit antenna 204.
The transmit circuitry of
Exemplary embodiments of the invention includes modulation of the receive device's current draw and modulation of the receive antenna's impedance to accomplish reverse link signaling. With reference to both
In the exemplary embodiments of
In
In
Reverse link signaling may be accomplished by switching between the DC operating state (
The rectifier 318 is connected to switch S2B, which is connected in series with resistor R2 and ground. The rectifier 318 also is connected to switch S3B. The other side of switch S3B supplies a DC power signal 322 to a receive device (not shown) to power the receive device, charge a battery, or a combination thereof.
In
In
In
In
Reverse link signaling may be accomplished by switching between the tuned operating state (
Of course, those of ordinary skill in the art will recognize that other combinations of switches S1B, S2B, and S3B may be used to create cloaking, generate reverse link signaling and supplying power to the receive device. In addition, the switches S1A and S1B may be added to the circuits of
Thus, when in a coupled mode signals may be sent from the transmitter to the receiver, as discussed above with reference to
The receiver and transmitter may communicate on a separate communication channel (e.g., Bluetooth, zigbee, etc). With a separate communication channel, the transmitter may determine when to switch between beacon mode and high power mode, or create multiple power levels, based on the number of receive devices in the coupling-mode region 510 and their respective power requirements.
Exemplary embodiments of the invention include enhancing the coupling between a relatively large transmit antenna and a small receive antenna in the near-field power transfer between two antennas through introduction of additional antennas into the system of coupled antennas that will act as repeaters and will enhance the flow of power from the transmitting antenna toward the receiving antenna.
In exemplary embodiments, one or more extra antennas are used that couple to the transmit antenna and receive antenna in the system. These extra antennas comprise repeater antennas, such as active or passive antennas. A passive antenna may include simply the antenna loop and a capacitive element for tuning a resonant frequency of the antenna. An active element may include, in addition to the antenna loop and one or more tuning capacitors, an amplifier for increasing the strength of a repeated near-field radiation.
The combination of the transmit antenna and the repeater antennas in the power transfer system may be optimized such that coupling of power to very small receive antennas is enhanced based on factors such as termination loads, tuning components, resonant frequencies, and placement of the repeater antennas relative to the transmit antenna.
A single transmit antenna exhibits a finite near-field coupling mode region. Accordingly, a user of a device charging through a receiver in the transmit antenna's near-field coupling mode region may require a considerable user access space that would be prohibitive or at least inconvenient. Furthermore, the coupling mode region may diminish quickly as a receive antenna moves away from the transmit antenna.
A repeater antenna may refocus and reshape a coupling mode region from a transmit antenna to create a second coupling mode region around the repeater antenna, which may be better suited for coupling energy to a receive antenna. Discussed below in
While the various transmit antennas and repeater antennas have been shown in general on surfaces, these antennas may also be disposed under surfaces (e.g., under a table, under a floor, behind a wall, or behind a ceiling), or within surfaces (e.g., a table top, a wall, a floor, or a ceiling).
Various exemplary embodiments as described herein are directed to various charging devices and systems configured to convey information related to one or more electronic devices positioned within one or more charging regions of a wireless charging device. It is noted that the information relating to an electronic device may be acquired by an associated charging device through any known and suitable wireless signaling method. For example only, information relating to an electronic device may be acquired by an associated charging device through feedback sent from the electronic device or by sensing a load on the electronic device. An example of a wireless signaling method is described in U.S. patent application Ser. No. 12/249,873, entitled “REVERSE LINK SIGNALING VIA RECEIVE ANTENNA IMPEDANCE MODULATION” filed on Oct. 10, 2008, the details of which are incorporated by reference herein.
As illustrated in
For example, indicator display 404A may be configured to display information relating to an electronic device 410A positioned within associated charging region 406A, indicator display 404B may be configured to display information relating to an electronic device 410B positioned within associated charging region 406B, and indicator display 404C may be configured to display information relating to an electronic device 410C positioned within associated charging region 406C.
Furthermore, each indicator display 404 may be configured to display an alphanumeric identifier of an electronic device positioned within an associated charging region. For example, each indicator display 404 may be configured to display a device label (e.g., a user name), a device type (e.g., cell phone, camera, etc.), or any combination thereof. As an example, indicator display 404A, which is associated with charging region 406A, may be configured to display alphanumeric text (e.g., “Jenn's cell phone”) identifying electronic device 410A positioned within charging region 406A.
Further, each indicator display 404 may be configured to display information relating to a charging status of an electronic device positioned within a corresponding charging region. For example, according to one exemplary embodiment, each indicator display 404 may be configured to display one or more flashing lights within an associated progress indicator 411 (i.e., progress indicator 411A, progress indicator 411B, and progress indicator 411C) to indicate whether an electronic device positioned within an associated charging region is being charged. Furthermore, each progress indicator 411 may be configured to indicate an amount of charge existing within an associated electronic device at a moment in time. For example, indicator display 404B may be configured to display two lights within progress indicator 411B indicating that electronic device 410B positioned within associated charging region 406B is charging and has “two bars” worth of charge. As will be understood by one of ordinary skill in the art, a progress indicator displaying three bars (i.e., three lights) indicates more charge than a progress indicator displaying two bars (i.e., two lights), which indicates more charge than a progress indicator displaying one bar (i.e., one light). In addition, in accordance with an exemplary embodiment, each indicator display 404 may be configured to display information to indicate that an electronic device positioned within an associated charging region is fully charged. For example, indicator display 404C may be configured to display three continuous lights within progress indicator 411C indicating that electronic device 410C positioned within associated charging region 406C is fully charged. Moreover, each indicator display 404 may be configured to display an amount of time expected to fully charge an electronic device positioned within an associated charging region.
Furthermore, charging device 402 may be configured to audibly convey information related to one or more electronic devices 410 positioned within charging regions 406. More specifically, for example, interface 401 may be configured to audibly convey a device label (e.g., a user name), a device type (e.g., cell phone, camera, etc.), or any combination thereof, for a specific electronic device. Furthermore, interface 401 may be configured to audibly convey information indicative of whether the specific electronic device is being charged, an amount of charge existing within the specific electronic device at a moment in time, or any combination thereof. In addition, interface 401 may be configured to audibly convey information indicating that the specific electronic device is fully charged or an amount of time expected to fully charge the specific electronic device. As an example, interface 401 may be configured to audibly identify electronic device 410B (e.g., audibly convey “Joe's camera”) positioned within charging region 406B and audibly convey a charging status of electronic device 410B (e.g., audibly convey “charging”). Additionally, as depicted in
Charging device 402 may also be configured to vibrate an electronic device in one of a plurality of patterns to indicate a charging status of the electronic device. As an example, charging device 402 may be configured to vibrate electronic device 410C in a first pattern to indicate that electronic device 410C is charging. Further, charging device 402 may be configured to vibrate electronic device 410A in a second pattern to indicate that electronic device 410A is fully charged.
Although charging device 402 is illustrated as having a ledge 415 configured for placement of one or more electronic devices, embodiments of the present invention are not so limited. Rather, charging device 402 may comprise any physical configuration so as to enable one or more electronic devices to be placed within a charging region. For example, charging device 402 may be configured in a manner so as to have a substantially horizontal surface configured for one or more electronic devices to be placed thereon. Furthermore, as described more fully below, charging device 402 may be implemented as a portable charging device (e.g., a bag) or a stationary charging device (e.g., a table).
As illustrated in
Furthermore, according to one exemplary embodiment, charging device 440 may be configured to audibly convey information related to a summary of the charging statuses of all electronic devices positioned within a charging region 443. For example only, interface 441 may be configured to convey audio in a first form (e.g., a beep) to indicate that at least one of electronic device 410A and electronic device 410B is being charged, or that both electronic device 410A and electronic device 410B are being charged. Furthermore, for example only, interface 441 may be configured to convey audio in a second form (e.g., a chime) to indicate that both electronic device 410A and electronic device 410A are fully charged. Moreover, for example only, interface 441 may be configured to convey audio in a third form (e.g., a buzz) to indicate that charging region 443 does not include at least one chargeable device. Additionally, for example only, interface 441 may be configured to convey audio in a fourth form (e.g., a ring) to indicate that charging region 443 includes one or more detectable, but non-chargeable devices, as described more fully below.
Another charging device 445, in accordance with an exemplary embodiment of the present invention, is illustrated in
Furthermore, charging device 445 may be configured to convey information to indicate that charging region 443′ includes one or more non-chargeable devices. In addition to having an interface 451 including indicator display 444, interface 451 may include an indicator display 447 configured to display information related to one or more non-chargeable devices positioned within charging region 443′. Specifically, for example, indicator display 447 may be configured to display one or more lights flashing in a distinguishable pattern to indicate that charging region 443′ includes non-chargeable device 449 positioned therein. Additionally, for example only, charging device 445 may be configured to convey audio in one of a plurality of forms to indicate that charging region 443′ includes non-chargeable device 449.
As illustrated in
Further, interface 421 may be configured to convey information related to a charging status of one or more electronic devices positioned within the charging region of charging device 420. For example, according to one exemplary embodiment, interface 421 may be configured to display one or more lights in display elements 425, positioned proximate a device identifier (e.g., “Camera”), in a distinguishable pattern to indicate whether an associated electronic device within the charging region of charging device 420 is being charged. In addition, interface 421 may be configured to display one or more lights in another distinguishable pattern to indicate that an associated electronic device within a charging region of charging device 420 is fully charged. Furthermore, for example, interface 421 may be configured to display one or more continuous lights associated with a device identifier to indicate that the electronic device is fully charged.
In addition, charging device 420 may be configured to convey audio. More specifically, for example, interface 421 may be configured to audibly convey an identifier such as a device label (e.g., a user name), a device type (e.g., cell phone, camera, etc.), or any combination thereof. Additionally, interface 421 may be configured to audibly convey information indicative of whether an associated electronic device positioned within a charging region of charging device 420 is being charged or whether an associated electronic device positioned within the charging region of charging device 420 is fully charged. As a non-limiting example, if a camera is positioned within the charging region of charging device 420, interface 421 may be configured to audibly identify the camera (e.g., audibly convey “camera”) and audibly convey a charging status of the camera (e.g., audibly convey “charged”).
It is noted that although the exemplary embodiments described above depict one or more devices (i.e., chargeable electronic devices and/or non-chargeable devices) positioned directly on a surface of a charging device, embodiments of the present invention are not so limited. Rather, the charging devices described above may be configured to charge and convey information concerning any chargeable electronic device positioned within a near-field of a transmit antenna integrated within the charging device. Accordingly, as an example, any one of the charging devices described above may be configured to charge and convey information concerning a chargeable electronic device that is positioned within a portable device such as, for example, a purse, a backpack, or a briefcase. Stated another way, a portable device (e.g., a bag) having a chargeable electronic device therein may be placed in and/or on any of the charging devices, as described hererin, and the charging device may charge and convey information identifying the chargeable electronic device and a charging status of the chargeable electronic device. As an example, with reference to
Furthermore, it is noted that a portable device (e.g., portable device 427) may include a repeater antenna, as described above, and, therefore, one or more chargeable electronic devices within the portable device may be charged via a charging device having a transmit antenna (e.g., charging device 420) and portable device having a repeater antenna (e.g., portable device 427). It is further noted that each charging device as described herein may be implemented as, for example only, a portable charging device such as a backpack, a briefcase, a purse, clothing, luggage, etc. Accordingly, portable device 427, as described with reference to
Furthermore, in accordance with an exemplary embodiment of the present invention, device 922 may be configured to audibly convey and/or display information concerning one or more wireless chargers, which may be configured to wirelessly charge device 922. More specifically, in one exemplary embodiment, device 922 may be configured to display a map illustrating locations of one or more wireless chargers configured to wirelessly charge device 922. In another exemplary embodiment, device 922 may be configured to provide a location, via text and/or an audible message, of one or more wireless chargers configured to wirelessly charge device 922. Furthermore, in another exemplary embodiment, device 922 may be configured to audibly convey and/or display navigational directions to the one or more wireless chargers.
As a non-limiting example, device 922 may be configured to provide a user with a location of, and navigation directions to, one or more wireless chargers that are closest to device 922. As a more specific example, and, as illustrated in
Various exemplary embodiments of the present invention, as described herein, may enable a user of a charging device, as described above, to be informed of a charging status of one or more electronic devices, which are positioned within a charging region of the charging device, and which may or may not be visible to the user.
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 embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
This application claims priority under 35 U.S.C. §119(e) to: U.S. Provisional Patent Application 61/152,363 entitled “KEEP TRACK OF OBJECTS FOR WIRELESS CHARGING” filed on Feb. 13, 2009, and assigned to the assignee hereof and hereby expressly incorporated by reference herein; and U.S. Provisional Patent Application 61/151,290, entitled “MULTI DIMENSIONAL WIRELESS CHARGER” filed on Feb. 10, 2009, and assigned to the assignee hereof and hereby expressly incorporated by reference herein.
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