U.S. patent application number 14/495776 was filed with the patent office on 2015-08-13 for wireless load modulation.
The applicant listed for this patent is SREENIVAS KASTURI, SHAHAR PORAT, SIVA RAMAKRISHNAN. Invention is credited to SREENIVAS KASTURI, SHAHAR PORAT, SIVA RAMAKRISHNAN.
Application Number | 20150229135 14/495776 |
Document ID | / |
Family ID | 53775785 |
Filed Date | 2015-08-13 |
United States Patent
Application |
20150229135 |
Kind Code |
A1 |
PORAT; SHAHAR ; et
al. |
August 13, 2015 |
WIRELESS LOAD MODULATION
Abstract
Techniques of load modulation are described herein. A wireless
power receiving unit may include a receiving coil to receive a
short beacon having a first time period, and a long beacon having a
second time period longer than the first time period. A controller
of the wireless power receiving unit is to initiate load modulation
at the receiving coil during the long beacon. The controller is
configured to continue to perform the load modulation during the
long beacon until sufficient power is received at the wireless
power receiving unit to initiate a wireless data transmission
during the long beacon.
Inventors: |
PORAT; SHAHAR; (Geva Carmel,
IL) ; KASTURI; SREENIVAS; (Hillsboro, OR) ;
RAMAKRISHNAN; SIVA; (Beaverton, OR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PORAT; SHAHAR
KASTURI; SREENIVAS
RAMAKRISHNAN; SIVA |
Geva Carmel
Hillsboro
Beaverton |
OR
OR |
IL
US
US |
|
|
Family ID: |
53775785 |
Appl. No.: |
14/495776 |
Filed: |
September 24, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61937881 |
Feb 10, 2014 |
|
|
|
Current U.S.
Class: |
307/104 |
Current CPC
Class: |
H02J 50/90 20160201;
H02J 50/12 20160201; H02J 7/00034 20200101; H02J 7/025 20130101;
H02J 50/80 20160201; H04W 4/80 20180201 |
International
Class: |
H02J 5/00 20060101
H02J005/00; H04W 4/00 20060101 H04W004/00; H02J 7/02 20060101
H02J007/02 |
Claims
1. A wireless power receiving unit, comprising: a receiving coil to
receive a short beacon having a first time period, and a long
beacon having a second time period longer than the first time
period; a controller to initiate load modulation during the long
beacon at the receiving coil; and wherein the controller is to
continue to perform the load modulation during the long beacon
until sufficient power is received at the wireless power receiving
unit to initiate a wireless data transmission during the long
beacon.
2. The wireless power receiving unit of claim 1, wherein the time
period of the long beacon has a minimum time and a maximum time,
and wherein the long beacon persists to the maximum time as long as
the load modulation persists.
3. The wireless power receiving unit of claim 1, wherein the
wireless data transmission comprises a sequence of load modulations
indicating a binary sequence.
4. The wireless power receiving unit of claim 3, wherein the load
modulation is performed in the binary sequence to indicate: a power
charging profile of a device housing the receiving coil via the
binary sequence; or a device identification of a device housing the
receiving coil via the binary sequence, or any combination
thereof.
5. The wireless power receiving unit of claim 1, further comprising
a Bluetooth Low Energy (BLE) module, wherein the wireless data
transmission comprises a BLE advertisement from the BLE module.
6. The wireless power receiving unit of claim 1, further comprising
load modulation circuitry wherein the controller is to direct the
load modulation circuitry to increase or decrease a load received
at the wireless power receiving unit.
7. The wireless power receiving unit of claim 1, further comprising
a direct current to direct current (DC2DC) converter, wherein the
controller is configured to direct the DC2DC converter to modulate
the load based on modulating rates of direct current
conversion.
8. The wireless power receiving unit of claim 1, wherein the short
beacon and long beacon are generated at a wireless power
transmitting unit having a transmitting coil, and wherein receiving
the short beacon at the wireless power receiving unit generates an
initial load change at the wireless power transmitting unit
indicating the presence of the wireless power receiving unit.
9. The wireless power receiving unit of claim 8, wherein the
wireless data transmission indicates the wireless power receiving
unit is a valid power receiving unit according to a wireless
transmission protocol associated with the wireless power
transmitting unit.
10. The wireless power receiving unit of claim 1, wherein the load
modulation comprises: an increase in load; or a decrease in load;
or any combination thereof.
11. A method of load modulation in a wireless component,
comprising: receiving a short beacon having a first time period at
a receiving coil from a transmitting coil; performing an initial
load change at the receiving coil to indicate the presence of the
receiving coil to the transmitting coil; receiving a long beacon
having a second time period longer than the first time period in
response to the load modulation at the receiving coil; and
performing a load modulation during the long beacon until
sufficient power is received at the wireless power receiving unit
to initiate a wireless data transmission during the long
beacon.
12. The method of claim 11, wherein the time period of the long
beacon has a minimum time and a maximum time, the method further
comprising persisting to transmit the long beacon to the maximum
time as long as the load modulation persists.
13. The method of claim 11, wherein the wireless data transmission
comprises a sequence of load modulations indicating a binary
sequence.
14. The method of claim 13, the further comprising: transmitting a
binary sequence of load modulation indicating a power charging
profile of a device housing the receiving coil via the binary
sequence; or transmitting a binary sequence of load modulation
indicating a device identification of a device housing the
receiving coil via the binary sequence, or any combination
thereof.
15. The method of claim 11, wherein the wireless data transmission
comprises a Bluetooth Low Energy (BLE) advertisement, wherein the
method comprises transmitting the BLE advertisement from a BLE
module.
16. The method of claim 11, the method further comprising
increasing or decreasing a load received at the wireless power
receiving unit by load modulation circuitry.
17. The method of claim 11, the method further comprising
modulating rates of direct current conversion at direct current to
direct current (DC2DC) converter.
18. The method of claim 11, wherein the short beacon and long
beacon are generated at a wireless power transmitting unit having a
transmitting coil.
19. The method of claim 18, wherein the wireless data transmission
indicates the wireless power receiving unit is a valid power
receiving unit according to a wireless transmission protocol
associated with the wireless power transmitting unit.
20. The method of claim 11, wherein the load modulation comprises:
an increase in load; or a decrease in load; or any combination
thereof.
21. A wireless power transmitting unit, comprising: a transmitting
coil to transmit a short beacon having a first time period and a
long beacon having a second time period relatively longer than the
first time period; a controller having logic, at least partially
comprising hardware logic, to: detect an initial load change at
upon generating a short beacon indicating a presence of a receiving
coil; issue a long beacon to the receiving coil in response to the
initial load change; and issue the long beacon as long as a load
modulation is detected.
22. The wireless power transmitting unit of claim 21, wherein the
time period of the long beacon has a minimum time and a maximum
time, and wherein the long beacon persists to the maximum time as
long as the load modulation persists.
23. The wireless power transmitting unit of claim 21, wherein the
long beacon persists until a wireless data transmission is received
from a wireless power receiving unit.
24. The wireless power transmitting unit of claim 21, wherein the
wireless data transmission comprises: a Bluetooth Low Energy (BLE)
transmission; or a binary sequence of the load modulation; or any
combination thereof.
25. The wireless power transmitting unit of claim 21, wherein the
wireless data transmission indicates a wireless power receiving
unit receiving the long beacon is a valid wireless power receiving
unit according to a wireless transmission protocol associated with
the wireless power transmitting unit.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to U.S. Provisional
Patent Application No. 61/937,881, filed Feb. 10, 2014, which is
incorporated herein by reference.
TECHNICAL FIELD
[0002] This disclosure relates generally to techniques for wireless
charging. Specifically, this disclosure relates to load modulation
during initialization phases of wireless charging.
Background Art
[0003] A basic wireless charging system may include a wireless
power transmitter unit (PTU) and a wireless power receiving unit
(PRU). For example, a PTU may include a transmit (Tx) coil, and a
PRU may include receive (Rx) coil. Magnetic resonance wireless
charging may employ a magnetic coupling between the Tx coil and the
Rx coil. A common issue seen in these types of wireless charging
systems is during an initialization phase. In an initialization
phase, the PTU attempts to detect whether a valid PRU is being
placed on or near the Tx coil of the PTU. For example, the PTU may
be configured to sense load variations during a first predetermined
beacon period indicated a device is on, or near the Tx coil. The
load variations may be caused by a PRU being placed on or near the
PTU, but may also be caused by a conductive metal of an object,
such as a coin, or a device having a non-valid receiving coil in
terms of a wireless charging protocol of the PTU.
[0004] For example, a PTU may power on during the first
predetermined beacon period to detect whether a load associated
with inductive coupling of the Tx coil by an object has changed. If
a change in load is sensed, e.g., compared to the previous period,
the PTU will power on for a second predetermined beacon period that
is relatively longer than the first predetermined beacon period.
For example, the first predetermined beacon period may be 30
milliseconds. The first predetermined beacon period may be
relatively short in comparison to a longer second beacon period of
100 milliseconds configured to follow the short beacon. If the
object causing the load change is not a valid device, the power
transmitted by inductive coupling to the non-valid device during
the long beacon may damage the non-valid device. Further, if the
device to be charged has little or no charge, the device may not be
able to load power charging operations, such as wireless data
transmission related to the wireless charging operations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is block diagram of a PTU having a sensing mechanism
to sense load variation in PRU;
[0006] FIG. 2 is a block diagram of the PRU having an example load
modulation mechanism;
[0007] FIG. 3 is a graph illustrating load modulations used to
communicate presence of a valid PRU;
[0008] FIG. 4 is a flow diagram of a PTU receiving load modulation;
and
[0009] FIG. 5 is a flow diagram of a PRU performing load
modulation.
[0010] The same numbers are used throughout the disclosure and the
figures to reference like components and features. Numbers in the
100 series refer to features originally found in FIG. 1; numbers in
the 200 series refer to features originally found in FIG. 2; and so
on.
DESCRIPTION OF THE ASPECTS
[0011] The present disclosure relates generally to techniques for
performing load modulation at a power receiving unit (PRU). As
discussed above, magnetic resonance wireless charging systems may
employ a magnetic coupling between a power transmitting unit (PTU)
having a transmit (Tx) coil, and a PRU having a receive (Rx) coil.
However, in order to save power, the PTU may power off when the PTU
is not coupled to a PRU. The PTU may only power on during
predetermined periods of time in order to sense any change in a
load indicating a PRU has potentially been placed on, or near the
PRU for charging. The predetermined periods of time may be referred
to herein as beacons. During an initialization phase, the PTU needs
to detect if a valid PRU is exists, and only then transmit energy
to charge a device having the valid PRU. As discussed above, if the
PTU attempts to charge a non-valid device, it may cause damage to
the non-valid device.
[0012] A valid device is a device having a PRU meeting a power
charging protocol of the PTU. A power charging protocol may be a
protocol associated with a standards organization such as the
specification provided by Alliance For Wireless Power (A4WP)
version 1.2.1, May 7, 2014. A non-valid device is a device that
does not have a PRU meeting a power charging profile of a charging
protocol associated with the PTU. A non-valid device may also
include a conductive object, such as a coin, a key, a remote
control, and the like, having a conductive material that may be
unintentionally coupled to the PTU during a beacon period.
[0013] The techniques described herein include a method for
performing load modulation at an Rx coil of a PRU. The load
modulation may prevent unnecessary charging, or power transmission,
by the PTU to non-valid devices or objects. As discussed above,
during a short beacon, a PTU may sense an initial load change due
to coupling of the Tx coil with a potential Rx coil of a PRU.
Subsequent to the short beacon, the PTU may power on during a long
beacon. During the long beacon, the PRU may modulate the load
received at the Rx coil such that the PTU may detect the load
modulation indicating that a valid PRU is coupled to the PTU.
[0014] FIG. 1 is block diagram of a PTU having a sensing mechanism
to sense load variation in PRU. The PTU 102 may be coupled to a PRU
104 via magnetic inductive coupling between resonators 106, 108, as
indicated by the arrow 110. The resonator 106 may be referred to
herein as a Tx coil 106 of the PTU 102. The resonator 108 may be
referred to herein as an Rx coil 108 of the PRU 104.
[0015] As discussed above, the PRU 104 may perform load modulation
to signal presence to the PTU 102. During an initialization phase,
the PTU 102 may issue a short beacon. For example, the short beacon
has a duration of 30 milliseconds. Upon issuing the short beacon,
the Tx coil 106 inductively couples to the Rx coil 108. The
inductive coupling may cause an initial load change detected by a
current sensor 112 of the PTU 102. The current sensor 112 may be an
ampere meter, a volt meter, or any other meter configured to sense
load variations occurring due to inductive coupling between the PTU
102 and another object, such as the PRU 104. The current sensor 112
may provide an indication of load change to a controller 114 of the
PTU 102. Upon detecting a load change during the short beacon, the
controller 114 may power on a power amplifier 116 configured to
receive direct current (DC) from a direct current (DC2DC) converter
118, and to amplify and oscillate the current. An oscillator 120
may oscillate the power provided at a given frequency and a
matching network 122 may be used to match the amplified oscillation
provided to the resonator 106 of the PTU 102 based on a wireless
power protocol standard, and also at a resonating frequency
associated with the PRU 104. The PTU 102 may issue a long beacon
after receiving an indication of the initial load change from the
PRU 104, e.g., via the current sensor 112. In some scenarios, the
long beacon has a duration of 95 milliseconds up to 3 seconds.
[0016] The PRU 104 may include a controller 124 configured to
detect current received at the Rx coil 108 resulting from an
inductive coupling between the Tx coil 106 and the Rx coil 108.
After detecting an inductive coupling during the short beacon, the
controller 124 may modulate a load associated with the current
received at the Rx coil 108 during the long beacon issued by the
PTU 102. In some examples, the load modulation may be performed by
the load modulation circuitry 126, discussed in more detail below.
In other examples, the load modulation may be performed at a direct
current to direct current (DC2DC) converter 128 of the PRU 104. The
DC2DC converter 128 is an electronic circuit configured to convert
a direct current (DC) from one voltage level to another after
receiving the voltage from a matching network rectifier 130. As
illustrated in FIG. 1, the DC2DC converter 128 provides a DC output
to a battery 132, or another current/power consuming component. The
DC2DC converter 128 may convert DC received as a result of the
inductive coupling of the Tx coil 106 and the Rx coil 108. In order
to perform modulation, the controller 124 may direct the DC2DC
converter 128 to vary the conversion such that a load is modulated
and detectable by the PTU 102. In other examples, the controller
124 may turn the DC2DC converter 128 on and off, resulting in a
load modulation detectable at the PTU 102. In this example, by
turning off the DC2DC converter 128, the modulated load is achieved
by a lower load than the normal load observed when the DC2DC
converter is running normally.
[0017] In some examples, the load modulation is achieved by
activating a shunt resistor, discussed in more detail below. In
this scenario, the modulated load is higher than the normal load.
In a further variant, the DC2DC converter 128 can be operated in a
power inefficient way, e.g., by switching its internal components
more often than necessary, thus causing losses due to switching, or
deliberately causing short periods of so called shoot-through
currents, thereby presenting a higher load at the RX coil and
subsequently to the TX coil via then inductive coupling 110. In
order to enable a flexible implementation at the PRU 104, the PTU
102 may be able to detect both kinds of load modulations--i.e.,
increased and decreased load. The PTU 102 may only consider the
magnitude of load modulation differences, not the polarity, thus
being able to uniformly handle different implementations of PRUs.
As there are typically more PTUs than PRUs and because PRUs
typically experience tighter constrains regarding size, weight and
cost, giving some more flexibility to the PRU design may be
beneficial.
[0018] A wireless data transmission component 134 of the PRU 104
may transmit wireless data to a wireless data transmission
component 136 of the PTU 102. In examples, the wireless data
transmission is a Bluetooth low energy (BLE) data transmission. The
BLE transmission may include an advertisement to the PTU 102
indicating that the PRU 104 is a valid PRU. In some examples, the
battery 132 may not have enough energy to support a wireless data
transmission operation via a BLE advertisement. However, as long as
the PRU 104 modulates load, the PTU 102 will continue to power on
the power amplifier 116 during the long beacon. Further, the PTU
102 may be configured to continue to run the power amplifier 116 to
a maximum time, such as 3 seconds for example, to enable the
battery 132 to receive sufficient charge to load a wireless data
transmission operation, or to drive the wireless data transmission
operation directly--i.e., without having to rely on power from the
battery 132. In some scenarios, the PTU 102 is configured to repeat
the long beacon power-on state until a wireless data advertisement
is received. The PTU 102 may continue to issue long beacons without
danger of transmission to an invalid PRU because the load
modulation identifies to some extent whether the PRU is a valid
PRU, such as the PRU 104.
[0019] In some aspects, the load modulation may reflect a binary
communication. For example, the load modulation performed by the
PRU 104 may sequenced in a way to provide a signal of 1 0 1 0,
e.g., by the sequence of providing, non-providing, providing,
non-providing, and the like, a load modulation where the sequence
presents the binary information 1 0 1 0. Other information may be
provided similarly. In this scenario, the wireless data
transmission is communicated via a specific sequence of load
modulation. The controller 114, upon identifying the sequence, may
determine or acknowledge the device type of the PRU 104, and
determine or acknowledge that the PRU 104 is a valid device. In
some aspects, the binary sequence of the load modulation may be
configured to match a binary data signal transmitted by the
wireless data transmission component 134, or vice versa. By
providing matched binary indications to the PTU 102, the PTU 102
may avoid wireless data coupling to a device that is not placed on
the PTU 102. For example, if the PTU 102 is next to another PTU
having a device including a valid PRU placed on the other PTU, the
PTU 102 may mistakenly communicatively couple to the device even
when the device is not placed on the PTU 102. However, the PTU 102
may reject wireless data coupling to devices that have not
previously, or subsequently, provided a binary sequence to the PTU
102 through load modulation. Because the sequence provided via load
modulation does not have to be available immediately at the PTU
102, the sequence may be sent at a later time, e.g., during the
long beacon, as opposed to a sequence sent right at the first
instance of load modulation. The comparison with the sequence
conveyed via the wireless interface can be done at the PTU 102, the
PRU 104, or both.
[0020] FIG. 2 is a block diagram of the PRU having an example load
modulation circuitry. The load modulation mechanism 202 illustrated
in FIG. 2 may be one example of the load modulation circuitry 126.
However, as discussed above, load modulation may be performed
without load modulation circuitry. For example, load modulation may
be implemented as operations of the controller 124 to direct the
DC2DC converter 128 to modulate the load.
[0021] The example of load modulation circuitry 202 illustrated in
FIG. 2 includes a resistor 204 and a switch 206. The switch 206 may
be electrically coupled to the controller 124. When the controller
124 detects a short beacon followed by a long beacon, the
controller 124 may open or close the switch 206 such that more or
less current flows across the resistor towards ground 208. For
example, the switch 206 may be a transistor. In this scenario, the
controller 124 may increase or decrease a bias voltage of the
transistor such that current flowing across the resistor 204 is
modulated.
[0022] Although not illustrated in FIG. 2, a load variation may be
implemented at the output of the DC2DC converter 128. In this
scenario, a shunt resistor may be coupled in between the DC2DC
converter 128 and the battery 132. A resistor and a switch, such as
the resistor 204 and the switch 206 may be alternatively coupled to
the output of the DC2DC converter 128. Other implementations may be
applicable wherein various components are used in the load
modulation discussed herein.
[0023] FIG. 3 is a graph illustrating load modulations used to
communicate presence of a valid PRU. The graph 300 includes a top
portion 302 indicating a current, or observed load, at the Tx coil
106 of the PTU 102, and a bottom portion 303 indicating load
modulation at the PRU 104. During a short beacon, indicated at 304,
306, 308, current may increase due to a conductive object being
placed on, or near the PTU 102 at time "t0" indicated at 310. The
resulting increase in current creates a load change, as indicated
at 312.
[0024] During the long beacon 314, the PRU will modulate the load
such that the PTU can detect the load modulations, as indicated at
316. Before the long beacon 314 is complete, the PRU may transmit a
wireless data signal, as indicated at 318. The wireless data signal
may be a BLE advertisement discussed above in reference to FIG. 1
and FIG. 2, before entering a charging phase, as indicated at 320.
The PTU may enter the charging phase 320 in response to receiving
the BLE advertisement.
[0025] Although not indicated in FIG. 3, load modulation 316 may be
performed during a short beacon, such as during one or more of the
short beacons 304, 306, 308. In this scenario, although the power
transmitted during the long beacon 314 may be relatively small in
comparison to the power transmitted during the charging phase 320,
the load modulation may be presented during an even smaller
interval, such as during a short beacon 304, 306, and/or 308. This
may prevent decrease the time it takes to begin a charging phase by
performing load modulation during a short beacon. Further, if the
PTU has enough battery to broadcast a BLE advertisement, such as
the wireless data signal 318, it may do so after receiving a load
modulation during one or more of the short beacons, rather than
waiting for the long beacon 314.
[0026] FIG. 4 is a flow diagram of a PTU receiving load modulation.
The PTU may be the PTU 102 of FIG. 1. The PTU 102 may transmit a
short beacon at 402 and wait a `t_cycle` period as indicated by
404. The t_cycle period is a time period between two short beacons.
During the short beacon 402, the PTU 102 may detect a load change.
If a load change is detected during the short beacon 402, the long
beacon is transmitted, as indicated at 406. If a load modulation
signal is detected during the long beacon 406, then the long beacon
will be extended. If a wireless data transmission is then received,
the PTU 102 will start charging at 408. As indicated at 410, if no
wireless data transmission is received, the PTU 102 may return to
the wait cycle 404 for a period of `t_cycle`. However, if the PTU
102 continues to detect a load modulation signal at 412, the long
beacon may continue to transmit, or be retransmitted, enabling a
device having no charge to receive sufficient power to send the
wireless data transmission and begin charging at 408.
[0027] FIG. 5 is a flow diagram of a PRU performing load
modulation. The PRU may be the PRU 104 configured to inductively
couple to a PTU 102 of FIG. 1. At 502, load modulation may be
performed after receiving an indication of a short beacon from the
PTU 102. The load modulation at the PRU 104 may be performed using
charge provided by the PTU 102 during the short beacon, or using
the charge provided by the PTU 102 during the long beacon. At 504,
wireless data transmission operations are booted and wireless data
transmissions, such as a BLE advertisement is transmitted. At 506,
the PRU 104 will discontinue load modulation signaling, and at 508,
the PRU 102 will be in a charging process to receive charge from
the PTU 102.
[0028] Example 1 includes a wireless power receiving unit. The
wireless power receiving unit includes a receiving coil to receive
a short beacon having a first time period, and a long beacon having
a second time period longer than the first time period. The
wireless power receiving unit further includes a controller of the
wireless power receiving unit to initiate load modulation during
the long beacon at the receiving coil. The controller is to
continue to perform the load modulation during the long beacon
until sufficient power is received at the wireless power receiving
unit to initiate a wireless data transmission during the long
beacon.
[0029] The time period of the long beacon has a time minimum and a
time maximum. The long beacon persists to the maximum time as long
as the load modulation persists. In some cases, the wireless data
transmission includes a sequence of load modulations indicating a
binary sequence. The load modulation performed in a binary sequence
may indicate a power charging profile of a device housing the
receiving coil via the binary sequence, a device identification of
a device housing the receiving coil via the binary sequence, or any
combination thereof.
[0030] The wireless power receiving unit may also include a
Bluetooth Low Energy (BLE) module. The wireless data transmission
includes a BLE advertisement from the BLE module. The wireless
power receiving unit may also include load modulation circuitry
wherein the controller is to direct the load modulation circuitry
to increase or decrease a load received at the wireless power
receiving unit.
[0031] The wireless power receiving unit may also include a direct
current to direct current (DC2DC) converter. In this case, the
controller is to direct the DC2DC converter to modulate load based
on modulating rates of direct current conversion.
[0032] In some cases, the short beacon and long beacon are
generated at a power transmitting unit having a transmitting coil.
Receiving the short beacon at the power receiving unit generates an
initial load change at the power transmitting unit indicating the
presence of the power receiving unit. Further, in some cases, the
wireless data transmission indicates the power receiving unit is a
valid power receiving unit according to a wireless transmission
protocol associated with the power transmitting unit.
[0033] A load modulation may include an increase in load. A load
modulation may also include a decrease in load. In some cases, load
modulation may include a combination of an increase in load and a
decrease in load.
[0034] Example 2 includes a method of load modulation in a wireless
component. The method includes receiving a short beacon having a
first time period at receiving coil from a transmitting coil,
performing an initial load change at the receiving coil to indicate
the presence of the receiving coil to the transmitting coil, and
receiving a long beacon having a second time period longer than the
first time period in response to the load modulation at the
receiving coil. The method further includes performing a load
modulation during the long beacon until sufficient power is
received at the wireless power receiving unit to initiate a
wireless data transmission during the long beacon.
[0035] The time period of the long beacon has a time minimum and a
time maximum. The long beacon persists to the maximum time as long
as the load modulation persists. In some cases, the wireless data
transmission includes a sequence of load modulations indicating a
binary sequence. The load modulation performed in a binary sequence
may indicate a power charging profile of a device housing the
receiving coil via the binary sequence, a device identification of
a device housing the receiving coil via the binary sequence, or any
combination thereof.
[0036] The method may also include transmitting a binary sequence
of load modulation indicating a power charging profile of a device
housing the receiving coil via the binary sequence, or transmitting
a binary sequence of load modulation indicating a device
identification of a device housing the receiving coil via the
binary sequence, or any combination thereof.
[0037] The wireless power receiving unit may also include a
Bluetooth Low Energy (BLE) module. The wireless data transmission
includes a BLE advertisement from the BLE module. The method may
include transmitting the BLE advertisement from a BLE module. The
method may also include increasing or decreasing a load received at
the wireless power receiving unit by load modulation circuitry.
[0038] In some cases, the method may include modulating rates of
direct current conversion at direct current to direct current
(DC2DC) converter. The short beacon and long beacon are generated
at a power transmitting unit having a transmitting coil in some
cases. The wireless data transmission may indicate the proper
receiving unit is a valid power receiving unit according to a
wireless transmission protocol associated with the power
transmitting unit.
[0039] A load modulation may include an increase in load. A load
modulation may also include a decrease in load. In some cases, load
modulation may include a combination of an increase in load and a
decrease in load.
[0040] Example 3 includes a wireless power transmitting unit. The
wireless power transmitting unit includes a transmitting coil to
transmit a short beacon having a first time period and a long
beacon having a second time period relatively longer than the first
time period. The wireless power transmitting unit may also include
a means to detect an initial load change at upon generating a short
beacon indicating a presence of a receiving coil, issue a long
beacon to the receiving coil in response to the initial load
change, and issue the long beacon as long as a load modulation is
detected.
[0041] In some cases, the means may include a controller having
logic, at least partially comprising hardware logic. In other
cases, the means may include modules implemented by a computer
processor. In yet other cases, the means may include a combination
of logic and processor-executable modules.
[0042] Example 4 includes a means configured to carry out the
method of Example 2. In some cases, the means may include a
controller having logic, at least partially comprising hardware
logic. In other cases, the means may include modules implemented by
a computer processor. In yet other cases, the means may include a
combination of logic and processor-executable modules.
[0043] Example 5 includes a wireless power system. The system may
include a transmitting coil to issue a short beacon having a first
time period, and a long beacon having a second time period longer
than the first time period. The system may also include a receiving
coil to receive the short beacon and the long beacon, and a
controller of a wireless power receiving unit to initiate load
modulation during the long beacon at the receiving coil. The
controller is configured to continue to perform the load modulation
during the long beacon until sufficient power is received at the
wireless power receiving unit to initiate a wireless data
transmission during the long beacon.
[0044] Example 6 includes an apparatus for wireless power. The
apparatus includes a receiving coil to receive a short beacon
having a first time period, and a long beacon having a second time
period longer than the first time period. The apparatus may also
include a means to initiate load modulation during the long beacon
at the receiving coil. The means to initiate load modulation is to
continue to perform the load modulation during the long beacon
until sufficient power is received at the wireless power receiving
unit to initiate a wireless data transmission during the long
beacon.
[0045] In some cases, the means may include a controller having
logic, at least partially comprising hardware logic. In other
cases, the means may include modules implemented by a computer
processor. In yet other cases, the means may include a combination
of logic and processor-executable modules.
[0046] Not all components, features, structures, characteristics,
etc. described and illustrated herein need be included in a
particular aspect or aspects. If the specification states a
component, feature, structure, or characteristic "may", "might",
"can" or "could" be included, for example, that particular
component, feature, structure, or characteristic is not required to
be included. If the specification or claim refers to "a" or "an"
element, that does not mean there is only one of the element. If
the specification or claims refer to "an additional" element, that
does not preclude there being more than one of the additional
element.
[0047] It is to be noted that, although some aspects have been
described in reference to particular implementations, other
implementations are possible according to some aspects.
Additionally, the arrangement and/or order of circuit elements or
other features illustrated in the drawings and/or described herein
need not be arranged in the particular way illustrated and
described. Many other arrangements are possible according to some
aspects.
[0048] In each system shown in a figure, the elements in some cases
may each have a same reference number or a different reference
number to suggest that the elements represented could be different
and/or similar. However, an element may be flexible enough to have
different implementations and work with some or all of the systems
shown or described herein. The various elements shown in the
figures may be the same or different. Which one is referred to as a
first element and which is called a second element is
arbitrary.
[0049] It is to be understood that specifics in the aforementioned
examples may be used anywhere in one or more aspects. For instance,
all optional features of the computing device described above may
also be implemented with respect to either of the methods or the
computer-readable medium described herein. Furthermore, although
flow diagrams and/or state diagrams may have been used herein to
describe aspects, the techniques are not limited to those diagrams
or to corresponding descriptions herein. For example, flow need not
move through each illustrated box or state or in exactly the same
order as illustrated and described herein.
[0050] The present techniques are not restricted to the particular
details listed herein. Indeed, those skilled in the art having the
benefit of this disclosure will appreciate that many other
variations from the foregoing description and drawings may be made
within the scope of the present techniques. Accordingly, it is the
following claims including any amendments thereto that define the
scope of the present techniques.
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