0001
`
`Ossia, Inc.
`Exhibit 1012
`PGR2016-00023
`U.S. Patent No. 9,124,125
`
`

`
`Patent Application Publication
`
`Oct. 4, 2012 Sheet 1 of 8
`
`US 2012/0248891 A1
`
`110
`
`102
`
`112
`
`FIG. 1
`
`. _ _ _ _ _ J _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ , _ _ _ _
`104‘\
`
`TX
`Antenna
`114
`
`RX
`Antenna
`, _ _ _ _ _ _ L _ _ _ _ _ _ _ _ _ , _ __
`118
`108‘\
`
`
`
`150
`
`ntenna
`
`156
`
`Ct
`
`152
`
`Cm
`
`154
`
`FIG. 3
`
`0002
`
`0002
`
`

`
`Patent Application Publication
`
`Oct. 4, 2012 Sheet 2 of 8
`
`US 2012/0248891 A1
`
`John Smith
`xxxx-xxxxxx
`
`FIG. 4
`
`0003
`
`0003
`
`

`
`Patent Application Publication
`
`Oct. 4, 2012 Sheet 3 of 8
`
`US 2012/0248891 A1
`
`_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ L _ _.,
`
`
`
`118
`
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`Ant
`
`i
`
`——————————————————————
`
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`
` 310: §Charging
`
`Device
`
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`5
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`
`0004
`
`

`
`Patent Application Publication
`
`Oct. 4, 2012 Sheet 4 of 8
`
`US 2012/0248891 A1
`
`280
`
`
`
`
`
`
`
`Tone
`Signal
`x 189
`
`282
`
`284
`
`286
`
`Tone
`Detector
`
`Tone
`Receiver
`
`Tone
`Antenna
`
`287
`
`288
`
`Dgtection
`igna
`Antenna
`
`
`
`Dgtection
`igna
`Transmitter
`
`TX
`Controner
`
`214
`201
`
`Wireless Power
`Transmit
`Circuit
`
`108
`
`114
`
`TX
`Am
`
`enna
`
`F requency
`Signals
`
`Communication
`D —
`evice
`
`Wireless Power Receiver
`
`FIG. 7
`
`287;; _________________81
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`814
`816
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`Analyzer
`
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`
`FIG. 8
`
`0005
`
`0005
`
`

`
`Patent Application Publication
`
`Oct. 4, 2012 Sheet 5 of 8
`
`US 2012/0248891 A1
`
`Eszomgm
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`0006
`
`0006
`
`
`
`

`
`Patent Application Publication
`
`Oct. 4, 2012 Sheet 6 of 8
`
`US 2012/0248891 A1
`
`Generate wireless
`charging field
`
`Transmit a first
`signal at a first
`frequency
`
`Transmit a second
`signal at a second
`frequency
`
`Detect a third signal
`at a third frequency
`that is a product of the
`first and second frequencies
`
`Reduce power
`of wireless charging field
`
`FIG. 11
`
`0007
`
`0007
`
`

`
`Patent Application Publication
`
`Oct. 4, 2012 Sheet 7 of 8
`
`US 2012/0248891 A1
`
`1202
`
`Initiate wireless
`
`charging
`system
`
`/ 1200
`
`1204
`
`1222
`
`1220
`
`1218
`
`Start detection
`mode
`
`Stop tone
`
`t
`
`Stop
`-tt-
`
`Turn _on
`
`1206
`
`
`
`
`
`Wireless
`power receiver
`present
`
`?
`
`Stop charging
`field
`
`1208
`
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`Transmit
`Initiate
`
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`charging
`detection
`tone
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`field
`threshold
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`
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`
`Turn off
`
`alarm signal
`
`1228
`
`Stop
`transmitting
`detection signal
`1230
`
`Stop tone
`receiver
`
`1232
`
`Start Charging
`field
`
`1238
`
`1236
`
`No
`
`Stop
`charging
`field
`
`1234
`
`Check
`change in
`
`
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`ln l00W9l'
`
`poweri‘
`nogmal
`
`
`FIG. 12
`
`0008
`
`0008
`
`

`
`Patent Application Publication
`
`Oct. 4, 2012 Sheet 8 of 8
`
`US 2012/0248891 A1
`
`
`
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`
`32
`
`0009
`
`0009
`
`

`
`US 2012/0248891 A1
`
`Oct. 4, 2012
`
`SYSTEMS AND METHODS FOR DETECTING
`AND PROTECTING A WIRELESS POWER
`COMMUNICATION DEVICE IN A WIRELESS
`POWER SYSTEM
`
`CROSS REFERENCE TO RELATED
`APPLICATIONS
`
`[0001] This application claims priority benefit under 35
`U.S.C. §ll9(e) to U.S. Provisional Patent Application No.
`61/470,380 entitled “NEAR FIELD COMMUNICATION
`CARDS DETECTION” filed on Mar. 31, 201 l, the disclosure
`of which is hereby incorporated by reference in its entirety.
`
`FIELD
`
`[0002] The present invention relates generally to wireless
`power. More specifically, the disclosure is directed to sys-
`tems, device, and methods for detecting a vulnerable device
`(e.g., a device that may be damaged by a wireless power
`transfer field), including near-field communication devices
`and radio-frequency identification (RFID) cards, within a
`charging region of a wireless power transmitter. Some
`embodiments relate to systems, devices, and methods for
`adjusting wireless power transfer and/or limiting wireless
`power delivery based on detection of vulnerable devices,
`including near-field communication devices, positioned
`within a charging region of a wireless power transmitter.
`
`BACKGROUND
`
`[0003] An increasing number and variety of electronic
`devices are powered via rechargeable batteries. Such devices
`include mobile phones, portable music players, laptop com-
`puters, tablet computers, computer peripheral devices, com-
`munication devices (e. g., Bluetooth devices), digital cameras,
`hearing aids, and the like. While battery technology has
`improved, battery-powered electronic devices increasingly
`require and consume greater amounts of power. As such,
`these devices constantly require recharging. Rechargeable
`devices are often charged via wired connections that require
`cables or other similar connectors that are physically con-
`nected to a power supply. Cables and similar connectors may
`sometimes be inconvenient or cumbersome and have other
`
`drawbacks. Wireless charging systems that are capable of
`transferring power in free space to be used to charge recharge-
`able electronic devices may overcome some of the deficien-
`cies of wired charging solutions. As such, wireless charging
`systems and methods that efiiciently and safely transfer
`power for charging rechargeable electronic devices are desir-
`able.
`
`[0004] A vulnerable device, such as a near field communi-
`cation (NFC) device, which is operating at the same fre-
`quency or capable of receiving power from a wireless power
`transmitter, may receive excessive power from the wireless
`power transmitter. Receiving excessive power may result in
`undesirable heating or destruction of the vulnerable device.
`
`[0006] According to one aspect, a method of detecting a
`communication device within a wireless power transfer
`region of a wireless power transmitter configured to transfer
`power to a device is disclosed. The method includes generat-
`ing a wireless power transfer field at a power level, transmit-
`ting a first signal at a first frequency and a second signal at a
`second frequency, detecting a third signal at a third frequency,
`the third frequency corresponding to an intermodulation
`product of the first frequency and the second frequency, and
`reducing the power level of the wireless power transfer field
`in response to the detection of the third signal.
`[0007] According to another aspect, an apparatus is dis-
`closed. The apparatus includes a wireless power transmitter
`configured to generate a wireless power transfer field at a
`power level, a detection signal transmitter configured to trans-
`mit a first signal at a first frequency and a second signal at a
`second frequency, a tone receiver configured to detect a third
`signal at a third frequency, the third frequency corresponding
`to an intermodulation product of the first frequency and the
`second frequency, and a controller configured to reduce the
`power level of the wireless power transfer field in response to
`the detection of the third signal.
`[0008] According to another aspect, an apparatus for
`detecting a communication device within a wireless power
`transfer region is disclosed. The apparatus includes means for
`generating a wireless power transfer field at a power level,
`means for transmitting a first signal at a first frequency and a
`second signal at a second frequency, means for detecting a
`third signal at a third frequency, the third frequency corre-
`sponding to an intermodulation product ofthe first frequency
`and the second frequency, and means for reducing the power
`level of the wireless power transfer field in response to the
`detection of the third signal.
`[0009] According to another aspect, a computer program
`product for processing data for a program configured to detect
`a communication device within a wireless power transfer
`region of a wireless power transmitter configured to transfer
`power to a device via a wireless power transfer field is dis-
`closed. The computer program product includes a non-tran-
`sitory computer-readable medium having stored thereon code
`for causing processing circuitry to transmit a first signal at a
`first frequency and a second signal at a second frequency,
`detect a third signal at a third frequency, the third frequency
`corresponding to an intermodulation product of the first fre-
`quency and the second frequency, and reduce a power level of
`the wireless power transfer field in response to the detection
`of the third signal.
`[0010]
`For purposes of summarizing the disclosure, certain
`aspects, advantages and novel features of the inventions have
`been described herein. It is to be understood that not neces-
`
`sarily all such advantages may be achieved in accordance
`with any particular embodiment of the invention. Thus, the
`invention may be embodied or carried out in a manner that
`achieves or optimizes one advantage or group of advantages
`as taught herein without necessarily achieving other advan-
`tages as may be taught or suggested herein.
`
`SUMMARY OF THE INVENTION
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0005] Various implementations of systems, methods and
`devices within the scope of the appended claims each have
`several aspects, no single one of which is solely responsible
`for the desirable attributes described herein. Without limiting
`the scope of the appended claims, some prominent features
`are described herein.
`
`FIG. 1 is a functional block diagram of a wireless
`[0011]
`power transfer system according to some embodiments.
`[0012]
`FIG. 2 is a more detailed block diagram of the wire-
`less power transfer system of FIG. 1.
`[0013]
`FIG. 3 illustrates a schematic diagram of a loop coil
`according to some embodiments.
`0010
`
`0010
`
`

`
`US 2012/0248891 A1
`
`Oct. 4, 2012
`
`FIG. 4 illustrates another wireless power transfer
`[0014]
`system including devices within a charging area of a wireless
`power transmitter according to some embodiments.
`[0015]
`FIG. 5 is a block diagram ofa wireless power trans-
`mitter according to some embodiments.
`[0016]
`FIG. 6 is a block diagram of a wireless power
`receiver according to some embodiments.
`[0017]
`FIG. 7 illustrates a block diagram of a presence
`detector according to some embodiments.
`[0018]
`FIG. 8 illustrates a more detailed block diagram of
`the components illustrated in FIG. 7 according to some
`embodiments.
`
`FIGS. 9A-9C illustrate some examples of a first
`[0019]
`frequency signal and a second frequency signal and a detected
`third frequency signal according to some embodiments.
`[0020]
`FIG. 10 illustrates a more detailed block diagram of
`the presence detector according to some embodiments.
`[0021]
`FIG. 11 illustrates a flowchart of a method of detec-
`tion and protection of a communication device according to
`some embodiments.
`[0022]
`FIG. 12 illustrates a flowchart of a method of detec-
`tion and protection of communication device according to
`some embodiments.
`
`FIG. 13 illustrates a block diagram of a system
`[0023]
`according to some implementations.
`
`DETAILED DESCRIPTION
`
`[0024] The detailed description set forth below in connec-
`tion with the appended drawings is intended as a description
`ofembodiments ofthe present invention and is not intended to
`represent the only embodiments in which the present inven-
`tion 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 pre-
`ferred or advantageous over other embodiments. The detailed
`description includes specific details for the purpose of pro-
`viding a thorough understanding of the embodiments of the
`invention. It will be apparent to those skilled in the art that the
`embodiments ofthe 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 embodiments presented herein.
`[0025] Wirelessly transferring power may refer to transfer-
`ring any form of energy associated with electric fields, mag-
`netic fields, electromagnetic fields, or otherwise that is trans-
`mitted from a transmitter to a receiver without the use of
`
`physical electrical conductors. (e.g., power may be trans-
`ferred through free space). The power output into a wireless
`field (e.g., a magnetic field) may be received or captured by a
`receiving antenna or coil to achieve power transfer.
`[0026]
`FIG. 1 is a functional block diagram of a wireless
`power transfer system according to some embodiments. Input
`power 102 may be provided to a wireless power transmitter
`104 for generating a field 106 (e.g., an electromagnetic field)
`for transferring energy from a wireless power transmitter 104
`to a wireless power receiver 108. During wireless power
`transfer, a wireless power receiver 108 may be coupled to the
`field 106 and generates an output power 110 for storage or
`consumption by a device (not shown) coupled to the wireless
`power receiver 108 for receiving the output power 110. The
`wireless power transmitter 104 and the wireless power
`receiver 108 are separated by a distance 112. In one embodi-
`ment, the wireless power transmitter 104 and the wireless
`power receiver 108 are configured according to a mutual
`
`resonant relationship. When the resonant frequency of wire-
`less power receiver 108 and the resonant frequency of wire-
`less power transmitter 104 are substantially the same or very
`close to one another, transmission losses between the wireless
`power transmitter 104 and the wireless power receiver 108 are
`minimal when the wireless power receiver 108 is located in
`the “near-field” of the field 106 generated by the wireless
`power transmitter 104. As such, wireless power transfer may
`be provided over larger distance in contrast to purely induc-
`tive solutions that may require large coils that require coils to
`be very close (e.g., in the range of ms). Resonant inductive
`coupling techniques may thus allow for improved efficiency
`and power transfer over various distances and with a variety
`of antenna or coil configurations. The term “coil” is intended
`to refer to a component that may wirelessly output or receive
`energy for coupling to another “coil.” The coil may also be
`referred to as an “antenna” of a type that is configured to
`wirelessly output or receive power. In some embodiments, a
`coil may also be referred to herein or configured as a “mag-
`netic” antenna or an induction coil.
`
`In one embodiment, The wireless power transmitter
`[0027]
`1 04 may be configured to output a time varying magnetic field
`with a frequency corresponding to the resonant frequency of
`the transmit coil 114. When the receiver is within the field
`
`106, the time varying magnetic field may induce a current in
`the receive coil 118. As described above, if the receive coil
`118 is configured to be resonant at the frequency of the
`transmit coil 118, energy may be efiiciently transferred. The
`AC signal induced in the receive coil 118 may be rectified as
`described above to produce a DC signal that may be provided
`to charge or to power a load.
`[0028] The wireless power transmitter 104 further includes
`a wireless power transmit coil 114 for outputting an energy
`transmission and wireless power
`receiver 108 further
`includes a wireless power receive coil 118 for energy recep-
`tion. As referred to herein, the near-field may correspond to a
`region in which there are strong reactive fields resulting from
`the currents and charges in the transmit coil 114 that mini-
`mally radiate power away from the transmit coil 114. In some
`cases the near-field may correspond to a region that is within
`about one wavelength (or a fraction thereof) of the transmit
`coil 114. The transmit and receive coils are sized according to
`applications and devices to be associated therewith. As
`described above, an efficient energy transfer occurs by cou-
`pling a large portion of the energy in the near-field of the
`wireless power transmit coil 114 to a wireless power receive
`coil 118 rather than propagating most of the energy in an
`electromagnetic wave to the far field. When positioned within
`the near-field, a coupling mode may be developed between
`the wireless power transmit coil 114 and the wireless power
`receive coil 118. The area around the wireless power transmit
`coil 114 and the wireless power receive 118 where this near-
`field coupling may occur may be referred to herein as a
`coupling-mode region.
`[0029]
`FIG. 2 shows a more detailed block diagram of the
`wireless power transfer system of FIG. 1. The wireless power
`transmitter 104 includes a wireless power signal generator
`122 (e.g., a voltage controlled oscillator), a driver 124 (e.g., a
`power amplifier) and a Tx impedance adjustment circuit 126.
`The wireless power signal generator 122 is configured to
`generate a signal at a desired frequency, such as 468.75 KHZ,
`6.78 MHZ or 13.56 MHZ, which may be adjusted in response
`to a signal generator control signal 123. The signal generated
`by the wireless power signal generator 122 may be provided
`0011
`
`0011
`
`

`
`US 2012/0248891 A1
`
`Oct. 4, 2012
`
`to a driver 124 configured to drive the transmit coil 114 at, for
`example, a resonant frequency of the transmit coil 114. The
`driver 124 may be a switching amplifier configured to receive
`a square wave from the wireless power signal generator 122
`(e.g., an oscillator) and output a sine wave. For example, the
`driver 124 may be a class E amplifier. The signal generated by
`the wireless power signal generator 122 is received by the
`driver 124 and may be amplified by the driver 124 with an
`amplification amount corresponding to an amplification con-
`trol signal 125. The Tx impedance adjustment circuit 126 may
`be connected to the output of the driver 124, and may be
`configured to adjust the impedance of the wireless power
`transmitter 104 based on the impedance ofthe wireless power
`transmit coil 114. In some embodiments, the Tx impedance
`adjustment circuit 126 may be configured to match the
`impedance of components of the wireless power transmitter
`104 with the impedance of the wireless power transmit coil
`114. While not illustrated, the wireless power transmitter 104
`may also include a filter connected to the output of the driver
`124 and the input ofthe Tx impedance adjustment circuit 126.
`The filter may be configured to filter out unwanted harmonics
`or other unwanted frequencies in the amplified signal.
`[0030] The wireless power receiver 108 may include an Rx
`impedance adjustment circuit 132 and a power conversion
`circuit 134 to generate a DC power output to charge a load 136
`as shown in FIG. 2, or power a device coupled to the wireless
`power receiver 108 (not shown). The Rx impedance adjust-
`ment circuit 132 may be included to adjust the impedance of
`the wireless power receiver 108 based on the impedance of
`the wireless power receive coil 118. In some embodiments,
`the Rx impedance adjustment circuit 132 may be configured
`to match the impedance of components of the wireless power
`receiver 108 with the impedance of the wireless power
`receive coil 118. The wireless power receiver 108 and wire-
`less power transmitter 104 may communicate on a separate
`communication channel 119 (e.g., a Bluetooth channel, a
`zigbee channel, a cellular channel, or the like).
`[0031] Wireless power receiver 108, which may initially
`have a selectively disablable associated load (e.g., load 136),
`may be configured to determine whether an amount of power
`transmitted by the wireless power transmitter 104 and
`received by the wireless power receiver 108 is appropriate for
`charging the load 136. Further, the wireless power receiver
`108 may be configured to enable a load (e.g., load 136) upon
`determining that the amount of power is appropriate. In some
`embodiments, a wireless power receiver 108 may be config-
`ured to directly utilize power received from a wireless power
`transfer field without charging of a load 136 (e.g., a battery).
`For example, a communication device, such as a near-field
`communication (NFC) or radio-frequency identification
`device (RFID may be configured to receive power from a
`wireless power transfer field and communicate by interacting
`with the wireless power transfer field and/or utilize the
`received power to communicate with a wireless power trans-
`mitter 104 or other devices.
`
`FIG. 3 illustrates a schematic diagram of a loop coil
`[0032]
`150 according to some embodiments. As illustrated in FIG. 3,
`coils used in embodiments may be configured as a “loop” coil
`150, which may also be referred to herein as a “magnetic”
`coil. Loop coils may be configured to include an air core or a
`physical core such as a ferrite core. Air core loop coils may be
`more tolerable to extraneous physical devices placed in the
`vicinity of the core. Furthermore, an air core loop coil may
`allow placement of other components or circuits (e.g., inte-
`
`grated circuits) within the core area. Further, an air core loop
`may enable placement of a wireless power receive coil (e.g.,
`wireless power receive coil 118 of FIG. 2) within a plane of a
`wireless power transmit coil (e.g., wireless power transmit
`coil 114 of FIG. 2), thereby increasing the coupling factor
`between the wireless power transmit coil 1 14 and the wireless
`power receive coil 118.
`[0033] Efficient transfer of energy between the wireless
`power transmitter 104 and wireless power receiver 108 may
`occur during matched or nearly matched resonance between
`the wireless power transmitter 104 and the wireless power
`receiver 108. However, even when resonance between the
`wireless power transmitter 104 and wireless power receiver
`108 are not matched, energy may be transferred, although the
`efficiency may be affected. As discussed above, energy trans-
`fer may occur by coupling energy within the near-field of the
`wireless power transmit coil 114 to the wireless power receive
`coil 118 positioned within an area of where the electromag-
`netic near-field is generated, rather than propagating the
`energy from the wireless power transmit coil 114 into free
`space.
`
`[0034] The resonant frequency of the loop or magnetic
`coils is based on the inductance and capacitance of the coils.
`Inductance in a loop coil is generally the inductance of the
`loop, whereas, capacitance may generally be included in the
`form of a capacitive component connected to the loop coil to
`create a resonant structure (e.g., an LC circuit) having a
`desired resonant frequency. As a non-limiting example,
`capacitor 152 and capacitor 154 may be connected to loop
`coil 150 to create a resonant circuit that selects a signal at a
`resonant frequency 156. Other components (e.g., variable or
`fixed inductors, variable or fixed capacitors, and/or variable
`or fixed resistors) may also be connected to the loop coil 150
`for controlling and adjusting the resonant frequency. For
`larger diameter loop coils 150, the size of capacitance needed
`to sustain resonance may decrease as the diameter or induc-
`tance of the loop increases. Furthermore, as the diameter of
`the loop or magnetic coil increases, the efficient energy trans-
`fer area ofthe near-field may increase. Other resonant circuits
`are possible. As another non-limiting example, a capacitor
`may be placed in parallel between the two terminals of the
`loop coil 150. For a wireless power transmit coil 114, the
`signal at the resonant frequency 156 may be provided as an
`input to the loop coil 150.
`[0035]
`In a wireless power charging system, unauthorized
`devices or other components may interfere with the operation
`of a charging device in transmitting power to a device to be
`charged. For example, when a vulnerable device is introduced
`to a wireless charging system, it may be best to either shut-
`down or lower the power transmitted to protect the system and
`the vulnerable device. NFC devices can absorb significant
`amounts of power and can significantly heat up and become
`damaged through interaction with a wireless power transfer
`field. For example, a NFC device, which is operating at the
`same frequency or capable ofreceiving power from a wireless
`power transmitter, may receive excessive power from the
`wireless power transmitter. Receiving excessive power may
`result in undesirable heating of the NFC device, which may
`damage the NFC device.
`[0036] According to some embodiments described herein,
`a system may be capable of allowing protection ofvulnerable
`devices, such as NFC devices and RFID cards, from being
`destroyed, and protection of the wireless power transmitter
`104 from operating in an inefficient state that could cause
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`transmitter 104. While
`damage to the wireless power
`described herein with reference to NFC devices and RFID
`
`cards, the systems and methods described herein may be
`applicable to the detection of other devices which are not
`intended to be subjected to a wireless power field. Several of
`the structures and functions discussed above are described in
`
`greater detail below.
`[0037]
`FIG. 4 illustrates another wireless power transfer
`system including devices within a wireless power transfer
`region 190 of a wireless power transmitter 104 according to
`some embodiments. As illustrated in FIG. 4, the system may
`include a charger 182 and a wireless power chargeable device
`184 within a wireless power transfer region 190 ofthe charger
`182. The charger 182 may be include a wireless power trans-
`mitter (e.g., as discussed above with reference to wireless
`power transmitter 104) for charging the wireless power
`chargeable device 184. The charger 182 may be, for example,
`a charging device (e.g., a charging mat) connected to a power
`source via a wired connection, a charging device configured
`to receive power wirelessly and transfer the received power to
`the wireless power chargeable device 184, or a combination
`thereof. The wireless power chargeable device 184 as refer-
`enced herein is a broad term that includes, for example, an
`electronic camera, video recorder, a web cam, a cellular tele-
`phone, smart phone, portable media player, personal digital
`assistant, a laptop, a tablet computer, or the like. While not
`illustrated, the system may include multiple wireless power
`chargeable devices 184 within the wireless power transfer
`region 190 of the charger 182.
`[0038] The system may further include a card 186 which
`includes a communication device 188, such as an near field
`communication (NFC) device, an RFID card, or the like). The
`card 186 may be an ID card (e.g., an access restricting security
`badge), a smart card, a credit card, or the like. The card 186
`may be configured to communicate via the communication
`device 188 to transfer information (e.g., identification, trans-
`action information, or the like. Although the communication
`device 188 is illustrated as included in a card 186, the com-
`munication device 188 is not limited thereto. For example, the
`communication device 188 may be included in a wireless
`power chargeable device 184 for communicating information
`regarding the wireless power chargeable device (e.g., identi-
`fication information, or the like). The communication device
`188 may use induction between a coil of the communication
`device 188 and a coil of a device in communication with the
`
`communication device 188 (e.g., near-field communication).
`[0039] As illustrated in FIG. 4, card 186 and wireless power
`chargeable device 184 may be positioned within a wireless
`power transfer region 190 of charger 182. The orientation of
`the devices is not restricted to the orientation ofthe devices as
`
`illustrated in FIG. 4. As will be discussed in greater detail with
`reference to FIG. 5 below, charger 182 may be configured to
`detect a communication device 188. Moreover, charger 182
`may be configured to protect a communication device 188,
`such as a NFC or RFID device, after detection thereof.
`[0040] As described herein, charger 182 may be configured
`to detect, according to one or more methods, one or more
`vulnerable devices (e.g., a communication device 188) posi-
`tioned within a wireless power transfer region 190 of a wire-
`less power transmitter 104. According to some embodiments,
`charger 182 may be configured to transmit detection signals
`and detect harmomcs and/or mixing products of the detection
`signals in order to detect a communication device 188.
`According to some embodiments, charger 182 may be con-
`
`figured to determine whether or not power, which is being
`transmitted by a wireless power transmitter 104 of charger
`182 within an associated wireless power transfer region 190,
`is unaccounted for. Charger 182 may be configured to deter-
`mine, via one or more measured properties associated with
`the wireless power transmitter 104, whether a communication
`device 188 is within a wireless power transfer region 190 of
`the charger 182.
`[0041] Charger 182 may be configured to, according to one
`or more methods, protect (e.g., reduce or possibly eliminate
`generation of a power transfer field) in the presence of one or
`more vulnerable devices (e.g., communication device 188),
`which are detected within an associate wireless power trans-
`fer region 190. For example, charger 182 may be configured
`in a manner to prevent a communication device 188, such as
`a NFC device, from being positioned within a region of a
`wireless power transmit coil 114 during wireless power
`charging. Therefore, the communication device 188 (e.g., a
`NFC device) may not be positioned within a zone with the
`strongest power transfer field. According to another exem-
`plary embodiment, charger 182 may be configured to reduce,
`or eliminate, (e.g., turn off) the power transferred therefrom
`based on the detection of the communication device 188.
`
`FIG. 5 is a block diagram ofa wireless power trans-
`[0042]
`mitter 104 according to some embodiments. Wireless power
`transmitter 104 may be included in a charger, such as a
`charger 182 as described with reference to FIG. 4 above. The
`wireless power transmitter 104 includes transmitter circuitry
`202 and a wireless power transmit coil 114. Transmitter cir-
`cuitry 202 provides RF power to the wireless power transmit
`coil 114 by providing an oscillating signal to drive the wire-
`less power transmit coil 114. Based on the oscillating signal,
`the wireless power transmit coil 1 14 generates an electromag-
`netic field for transmitting energy from the wireless power
`transmitter 104. The wireless power transmitter 104 may
`operate at any suitable frequency. By way of example, wire-
`less power transmitter 104 may operate at the 13.5 6 MHZ ISM
`band.
`
`[0043] Transmitter circuitry 202 includes a TX impedance
`adjustment circuit 126 configured to adjust the impedance of
`the transmitter circuitry 202 based on an impedance of the
`wireless power transmit coil 114 and a low pass filter (LPF)
`208 in order to maximize power transmitted by the wireless
`power transmitter 104. The LPF 208 may be configured to
`reduce harmonic emissions to levels to prevent self-j amrning
`of devices coupled to wireless power receivers 108. Other
`embodiments may include different filter topologies, includ-
`ing but not limited to, notch filters that attenuate specific
`frequencies while pas sing others and may include an adaptive
`impedance match, that can be varied based on measurable
`transmit metrics, such as output power to the coil or DC
`current drawn by a driver. Transmitter circuitry 202 further
`includes a driver 124 configured to drive an RF signal as
`determined by an wireless power signal generator 122. The
`transmit circuitry 202 may include discrete devices or cir-
`cuits, and/or may include an integrated circuit. An RF power
`output from wireless power transmit coil 114 may be within a
`range of about 2-5 Watts, but is not limited thereto.
`[0044] Transmitter circuitry 202 further includes a Tx con-
`troller 214 for enabling the wireless power signal generator
`122 during transmit phases (or duty cycles) for specific
`receivers, for adjusting the frequency or phase of the oscilla-
`tor, and for adjusting the output power level for implementing
`a communication protocol for interacting with neighboring
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`devices through their attached receivers. Adjustment of oscil-
`lator phase and related circuitry in the transmission path
`allows for reduction of out of band emissions, especially
`when t