U.S. patent number RE46,938 [Application Number 14/939,878] was granted by the patent office on 2018-07-03 for inductive data communication.
This patent grant is currently assigned to TRIUNE IP LLC. The grantee listed for this patent is TRIUNE IP LLC. Invention is credited to Amer Atrash, Andrew Blaszczak, Jonathan Knight, Michael Sullivan, Ross Teggatz.
United States Patent |
RE46,938 |
Atrash , et al. |
July 3, 2018 |
**Please see images for:
( Certificate of Correction ) ** |
Inductive data communication
Abstract
Data transmission systems and methods are disclosed in which a
transmitter and a receiver, each having an inductor, are configured
for wirelessly transferring data and power between them. Error
detection is implemented for implementing error correction
techniques by making corrections at the receiver, at the
transmitter, or both. In preferred embodiments of the invention,
error correction approaches include oversampling, power
adjustments, and frequency adjustments. In preferred
implementations, the systems and methods are used for transmitting
both power and data using a single pair of inductors.
Inventors: |
Atrash; Amer (Plano, TX),
Knight; Jonathan (Plano, TX), Teggatz; Ross (Plano,
TX), Sullivan; Michael (Plano, TX), Blaszczak; Andrew
(Plano, TX) |
Applicant: |
Name |
City |
State |
Country |
Type |
TRIUNE IP LLC |
N/A |
N/A |
N/A |
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Assignee: |
TRIUNE IP LLC (Plano,
TX)
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Family
ID: |
44560441 |
Appl.
No.: |
14/939,878 |
Filed: |
November 12, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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61312249 |
Mar 10, 2010 |
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61312248 |
Mar 10, 2010 |
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61312247 |
Mar 10, 2010 |
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61312246 |
Mar 10, 2010 |
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Reissue of: |
13045493 |
Mar 10, 2011 |
8583037 |
Nov 12, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04B
5/0037 (20130101); H02J 5/005 (20130101); H04B
5/0031 (20130101); H02J 7/025 (20130101); H04B
5/0031 (20130101); H04B 5/0081 (20130101); H02J
50/10 (20160201) |
Current International
Class: |
H04B
5/00 (20060101) |
Field of
Search: |
;455/41.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Tarae; Michelle
Attorney, Agent or Firm: Jackson Walker LLP Rourk;
Christopher J. Hayes; Thomas B.
Parent Case Text
PRIORITY ENTITLEMENT
This application is entitled to priority based on Provisional
Patent Application Ser. Nos. 61/312,246; 61/312,247; 61/312,248;
and 61/312,249; filed on Mar. 10, 2010, which are incorporated
herein for all purposes by this reference. This application and the
Provisional Patent Applications have at least one common inventor.
Claims
We claim:
1. A data transmission system comprising: a transmitter having a
transmitter inductor configured for wirelessly coupling with; a
receiver having a receiver inductor, wherein data transmitted from
the transmitter inductor may be received as a data signal by the
receiver inductor, wherein the transmitter inductor is adapted for
transmitting both power and data to the receiver inductor, wherein
the transmitted power is operable to power an electronic device
associated with the receiver; and an error detector for identifying
the presence of data error in the data signal, wherein the error
detector is configured to perform one or more of, a receiver error
correction algorithm, and a transmitter error correction
algorithm.
2. The system according to claim 1 wherein the receiver is
configured to increase and decrease sample size in response to the
receiver error correction algorithm.
3. The system according to claim 1 wherein the receiver is
configured to increase and decrease sample points in response to
the receiver error correction algorithm.
4. The system according to claim 1 wherein the receiver is
configured to shift sampling in response to the receiver error
correction algorithm.
5. The system according to claim 1 wherein the transmitter inductor
is configured to increase and decrease a transmission power in
response to the transmitter error correction algorithm.
6. The system according to claim 1 wherein the transmitter inductor
is configured to increase and decrease a transmission frequency in
response to the transmitter error correction algorithm.
7. The system according to claim 1 adapted for bidirectional
exchange of data.
8. The system according to claim 1 wherein the transmitter
comprises one of a power converter, or an energy storage device
charger.
9. The system according to claim 1 wherein the electronic device
associated with the receiver comprises one of a computer device, a
communication device, an imaging device, a display device, an
energy storage device, or a peripheral device.
10. A data transmission method comprising the steps of: wirelessly
transmitting a data signal from a transmitting inductor to a
receiving inductor; wirelessly transmitting a power signal from the
transmitting inductor to the receiving inductor, wherein the
transmitted power signal is operable to power an electronic device
associated with the receiving inductor; identifying the presence of
data error in the data signal; and performing one or more error
correction algorithm for improving the data signal.
11. The method according to claim 10 further comprising using the
data signal to transfer information about the power signal.
12. The method according to claim 10 further comprising alternating
the transmission of a data signal with the transmission of the
power signal.
13. The method according to claim 10 wherein the transmitting steps
are bidirectional.
14. The method according to claim 10 wherein identifying the
presence of data error in the data signal further comprises
comparing the data signal to an inverted data signal.
15. The method according to claim 10 wherein the receiving inductor
oversamples the data signal.
16. The method according to claim 10 wherein the receiving inductor
oversamples the data signal, and wherein the performing one or more
error correction algorithm for improving the data signal comprises
shifting a sampling window.
17. The method according to claim 10 wherein the receiving inductor
oversamples the data signal, and wherein the performing one or more
error correction algorithm for improving the data signal comprises
changing a size of a sampling window.
18. The method according to claim 10 wherein the receiving inductor
oversamples the data signal, and wherein the performing one or more
error correction algorithm for improving the data signal comprises
changing a number of sampling points.
19. The method according to claim 10 wherein the receiving inductor
oversamples the data signal, and wherein the performing one or more
error correction algorithm for improving the data signal comprises
changing a transmission power.
20. The method according to claim 10 wherein the receiving inductor
oversamples the data signal, and wherein the performing one or more
error correction algorithm for improving the data signal comprises
changing a transmission frequency.
21. The method according to claim 10 further comprising the step of
dynamically tuning at least one of the transmitter and receiver for
optimizing the data signal.
.Iadd.22. A data transmission system comprising: a transmitter
having a transmitter inductor configured for wirelessly coupling
with; a receiver having a receiver inductor, wherein data
transmitted from the transmitter inductor may be received as a data
signal by the receiver inductor, wherein the transmitter inductor
is adapted for transmitting both power and data to the receiver
inductor, wherein the transmitted power is operable to power an
electronic device associated with the receiver; and a signal
strength detector for modifying a signal strength of the data
signal, wherein the signal strength detector is configured to
implement a signal strength adjustment algorithm..Iaddend.
.Iadd.23. A data transmission method comprising the steps of:
wirelessly transmitting a data signal from a transmitting inductor
to a receiving inductor; wirelessly transmitting a power signal
from the transmitting inductor to the receiving inductor, wherein
the transmitted power signal is operable to power an electronic
device associated with the receiving inductor; determining a signal
strength of the data signal; and performing one or more signal
strength adjustment algorithms for improving the data
signal..Iaddend.
.Iadd.24. The system according to claim 22 wherein the receiver is
configured to increase and decrease sample size..Iaddend.
.Iadd.25. The system according to claim 22 wherein the receiver is
configured to increase and decrease sample points..Iaddend.
.Iadd.26. The system according to claim 22 wherein the receiver is
configured to shift sampling..Iaddend.
.Iadd.27. The system according to claim 22 wherein the transmitter
inductor is configured to increase and decrease a transmission
power..Iaddend.
.Iadd.28. The system according to claim 22 wherein the transmitter
inductor is configured to increase and decrease a transmission
frequency..Iaddend.
.Iadd.29. The system according to claim 22 adapted for
bidirectional exchange of data..Iaddend.
.Iadd.30. The system according to claim 22 wherein the transmitter
comprises one of a power converter, or an energy storage device
charger..Iaddend.
.Iadd.31. The system according to claim 22 wherein the electronic
device associated with the receiver comprises one of a computer
device, a communication device, an imaging device, a display
device, an energy storage device, or a peripheral
device..Iaddend.
.Iadd.32. The method according to claim 23 further comprising using
the data signal to transfer information about the power
signal..Iaddend.
.Iadd.33. The method according to claim 23 further comprising
alternating the transmission of a data signal with the transmission
of the power signal..Iaddend.
.Iadd.34. The method according to claim 23 wherein the transmitting
steps are bidirectional..Iaddend.
.Iadd.35. The method according to claim 23 further comprising
comparing the data signal to an inverted data signal..Iaddend.
.Iadd.36. The method according to claim 23 wherein the receiving
inductor oversamples the data signal..Iaddend.
.Iadd.37. The method according to claim 23 further comprising
shifting a sampling window..Iaddend.
.Iadd.38. The method according to claim 23 further comprising
changing a size of a sampling window..Iaddend.
.Iadd.39. The method according to claim 23 further comprising
comprises changing a number of sampling points..Iaddend.
.Iadd.40. The method according to claim 23 further comprising
changing a transmission power..Iaddend.
.Iadd.41. The method according to claim 23 further comprising
changing a transmission freguency..Iaddend.
.Iadd.42. The method according to claim 23 further comprising the
step of dynamically tuning at least one of the transmitter and
receiver for optimizing the data signal..Iaddend.
Description
TECHNICAL FIELD
The invention relates to wireless data transfer. In particular, the
invention is directed to wireless data transfer apparatus and
methods using coupled inductors.
BACKGROUND OF THE INVENTION
It is known to use coupled inductors to facilitate wireless data
transfer. Wireless power transmission can also be accomplished
using coupled inductors. Several challenges arise in using coupled
inductors for sending and receiving data in the presence of active
inductive power transmission. Among them, maintaining data
integrity and bandwidth are of concern.
Due to these and other problems and potential problems, improved
couple inductor power and data transmission would be useful and
advantageous contributions to the arts.
SUMMARY OF THE INVENTION
In carrying out the principles of the present invention, in
accordance with preferred embodiments, the invention provides
advances in the arts with novel methods and apparatus directed to
the transfer of data using an inductive coupling. In preferred
embodiments, systems include capabilities for power transfer as
well as unidirectional and bidirectional data transfer.
According to aspects of the invention, examples of preferred
embodiments include data transmission systems and methods with a
transmitter inductor for wirelessly transmitting a data signal to a
receiver inductor. An error detector is provided for identifying
data error. The error detector triggers the performance of a
receiver error correction algorithm and/or a transmission error
correction algorithm.
According to additional aspects of the invention, in examples of
preferred embodiments, oversampling may be used to increase and
decrease sample size, increase and decrease the number of sample
points, or shift the sample window in response to the receiver
error correction algorithm.
According to more aspects of the invention, preferred embodiments
also include capabilities for responsively increasing and
decreasing the transmission power and/or frequency based on the
transmission error correction algorithm.
According to another aspect of the invention, preferred systems and
methods are adapted for transmitting and receiving both power and
data
According to an additional aspect of the invention, the preferred
systems and methods may be implemented in configurations adapted
for the bidirectional exchange of data.
The invention has advantages including but not limited to one or
more of, improved bandwidth, improved data integrity, and improved
power transfer control. These and other advantageous features and
benefits of the present invention can be understood by one skilled
in the arts upon careful consideration of the detailed description
of representative embodiments of the invention in connection with
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more clearly understood from
consideration of the following detailed description and drawings in
which:
FIG. 1 is a simplified schematic circuit diagram illustrating an
example of preferred embodiments of systems for wireless data
communication according to the invention;
FIG. 2 is a diagram illustrating an example of an algorithm for
controlling the operation of systems and methods for receiving
wireless data according to an exemplary embodiment of the
invention;
FIG. 3 is a diagram illustrating an example of an algorithm for
controlling the operation of systems and methods for transmitting
wireless data communication according to an exemplary embodiment of
the invention; and
FIG. 4 is a diagram illustrating an example of an algorithm for
controlling the operation of systems and methods for wireless data
communication according to an exemplary embodiment of the
invention.
References in the detailed description correspond to like
references in the various drawings unless otherwise noted.
Descriptive and directional terms used in the written description
such as right, left, back, top, bottom, upper, side, et cetera,
refer to the drawings themselves as laid out on the paper and not
to physical limitations of the invention unless specifically noted.
The drawings are not to scale, and some features of embodiments
shown and discussed are simplified or amplified for illustrating
principles and features, as well as anticipated and unanticipated
advantages of the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
A related application, which is hereby incorporated herein for all
purposes by this reference, U.S. patent application Ser. No.
12/813,180 includes wireless data receiving systems and techniques
using coupled inductors. The related application and the present
application have a common assignee and at least one inventor in
common.
It has been determined that high inductance coils (micro-Henries)
switched at low frequencies (hundreds of kHz) are effective for
power transfer in applications such as battery chargers and power
converters, for example. In order to transmit a high bandwidth of
data effectively, however, several challenges arise. Tuning of the
system is often required in order to optimize transmission
frequency in the presence of parasitic elements that cause ringing
or otherwise distort the data signal. Managing peak currents in the
inductors, maintaining bandwidth in the presence of varying system
conditions, e.g., changes in temperature, coil alignment, or
distance between coils, and interference when sending and receiving
data in the presence of inductive power transmission can also
present problems. The inventors have determined that a reliable
system for data and power transmission can be implemented,
preferably using smaller inductance coils (10's to 100's of
nano-Henries), switched at much higher frequencies (10's to 100's
of MHz).
A simple illustration is shown in FIG. 1. The system 100 includes a
transmitter 102 having a transmitting inductor 104. A receiver 106
has a receiver inductor 108. Preferably, the inductors have
inductance values are on the order of micro-Henries. The respective
inductors, 104, 108, preferably reside in electronic apparatus
having additional functionality. For example, the transmitter may
reside within a battery charger or power inverter apparatus 107.
The receiver may reside in a communication, computer, imaging or
other device 109, to cite a few examples. The respective inductors
104, 108, are placed within their respective apparatus such that
they may be placed in physical proximity for inductive coupling
during operation such that the inductors are in communication with
one another for the exchange of power and/or data. The system 100
drives the inductors on one side (VACT1 and VACT2) and receives on
the other side (VACR1 and VACR2). Such systems can be utilized for
high bandwidth data transmission as well as power transfer across
the inductive coupling (104, 108). The receiver 106 preferably
includes an error detection mechanism 110 whereby the presence of
errors in the received data signal may be identified. Upon
detection of data errors, the system is adapted to implement one or
more error correction algorithms designed to enhance data reception
and/or transmission.
The placement of a resistor or other impedance element between the
AC inputs of the receiver can be used to tune the frequency
response and can eliminate ringing at the receiver terminals, as
shown at R. The selection of a suitable resistor value attenuates
or eliminates the ringing that otherwise would result from system
parasitics. Too large a resistance value does not sufficiently
dampen the ringing. Too small a resistance value interferes with
the data signal. The peaking at high frequency causes ringing in
the transient signal and can cause data errors if not managed
properly. An extension of this basic principle uses an adjustable
resistor such as a digitally controlled resistor or RDAC. Using an
adjustable resistor allows the system to respond to changing
environmental conditions, such as changes in temperature and
changes in coil alignment. In any configuration, the system can be
tuned automatically for improved system performance. This can
result in fewer bit errors or higher transmission frequencies. This
tuning can be done once at system startup, or periodically during
normal operation, or in response to operational parameters. If the
received data stream is oversampled, the oversampled data may be
used to evaluate signal integrity. Thus, the adjustable resistor
can be tuned during data transmission to improve the signal
integrity and maintain an acceptable error rate and/or preferred
transmission frequency.
In operation, the system 100 input is preferably returned to a
known default value during periods when data is not being
transmitted. To achieve this, the receiver inputs are preferably
biased to drift to a known state when not being driven. An
alternative is to implement the resistor R between the receiver
terminals using two adjustable resistors, which may be used to set
the appropriate bias levels. The adjustable resistors provide
damping for improving signal integrity and also provide a known
bias to the system during undriven states. Another benefit of using
an adjustable resistor configuration is that it allows for the use
of multiple transmission frequencies. Ringing in the system is
highly dependent on the system parametrics such as parasitic
capacitance and resistance as well as coil inductance. These
parameters can be functions of the excitation frequency and vary as
the frequency changes. Therefore, the system can exhibit different
behavior at different transmission frequencies and may be
dynamically adjusted for improved operation at any given
frequency.
There are additional advantages to utilizing inductive data
transmission and inductive power transmission simultaneously. In a
system transmitting both power and data, the power loop can be
regulated using communication through the inductive data path. This
path has much higher bandwidth than other communication techniques
such as modulating the power signal. Providing a high speed data
path also enables additional functionality. Using the high speed
data path for power control permits higher bandwidth in the power
system and faster response times. In many systems, such as power
converters and battery chargers, a separate charger IC or other
voltage regulator on the secondary side may be used to control the
secondary side voltage. Use of a high bandwidth feedback loop
eliminates the need for the additional regulator on the secondary
side. Voltage and/or current control can be achieved using the
power loop with high bandwidth control through the coupled inductor
data link. In many systems, the secondary side may advantageously
have additional protection features built in to protect the
secondary side circuits from over-voltage conditions. Preferably,
if response times are fast, additional protection circuits on the
secondary side may be unnecessary, reducing system cost and
area.
Transmission of power and data simultaneously may potentially
result in interference between the two paths. This has the
potential to cause bad or missing bits in the data stream. In order
to avoid this problem, the data and power signals may be
alternated. Using this method, the power signal is periodically
stopped. During this dead time in the power transmission, bursts of
high frequency data are sent. Since the data bandwidth is very
high, significant amounts of data can be transmitted even in a
short window of time.
Sending and receiving data within the coupled inductor data
transfer system may include the use of digital encoding and may be
performed with a defined protocol or with a unique protocol
determined for a particular application. Various techniques may
also be employed for assuring data reliability and integrity.
Oversampling of the received data may be performed to increase the
reliability of the data. If the recovered oversampled data
indicates that reliability is decreasing, the system is preferably
adapted to take one or more dynamic steps to increase reliability
of the recovered data. Preferably, the oversampling window may be
shifted in either direction, either to the left or to the right of
the current oversampling window. Alternatively, or additionally,
the oversampling window size may be changed, either decreasing or
increasing the window until an improvement is detected. In another
available step, a change may be made in the number of sampling
points used to determine the recovered data value, either
decreasing or increasing the number of sampling points. Various
functions may be used to seek the optimum sample, such as a simple
Boolean function or a suitable more sophisticated algorithm.
FIG. 2 is a diagram of an algorithm 200 for preserving data
integrity in accordance with an exemplary embodiment of the
invention. The algorithm 200 may be implemented using a computer,
signal processing platform, or other programmable device. Data is
transmitted 202 by a suitable transmitter and is received as a data
signal for processing 204. In an error detection step 206, the data
signal is checked for the presence of errors. Error checking may
include techniques such as comparison with known data values or
other suitable procedures. If no detectable errors are found 208
the data may be accepted and transferred or further processed
according to the requirements of an associated application. In the
event a data error is detected 210, receiver error correction steps
may be implemented. In preferred embodiments of the invention, one
or more of the above-mentioned oversampling techniques is used
until data with acceptable integrity is obtained. Additional and
alternative sampling techniques may also be used including but not
limited to retransmission of data. Additional data received 204 is
evaluated 206 in a similar manner and either accepted 208 or
rejected as steps to adapt the sampling 210 to prevailing
conditions are reiterated.
In a further example on the transmission side, the signal strength
may be adaptively adjusted as needed. For example, in the event the
coils become misaligned, imperfectly oriented, or their separation
distance increases, the signal strength at the receiver tends to
degrade. In this case, the transmit side of the system preferably
increases its transmission signal strength as required, for example
by increasing the drive voltage. Alternatively, or additionally, if
the signal strength becomes degraded, the system may transmit using
a different transmission frequency. Using a slower transmission
rate may improve the signal integrity. The transmission rate may
subsequently be increased in the event conditions improve.
FIG. 3 is a diagram depicting an algorithm 300 for adjusting
transmission strength and/or frequency in accordance with an
exemplary embodiment of the invention. The algorithm 300 may be
implemented using a computer, signal processing platform, or other
programmable device. Data is transmitted 302 by a suitable
transmitter and is received as a data signal for processing 304. In
an error detection step 306, the data signal is checked for the
presence of errors. Error checking may include techniques such as
comparison with known data values or other suitable procedures. If
no detectable errors are found 308 the data may be accepted and
transferred or further processed according to the requirements of
an associated application. In the event a data error is detected
310, one or more transmission error correction steps may be
implemented. In preferred embodiments of the invention, the data
signal frequency and/or amplitude may be adjusted and subsequent
received data evaluated 306 until an acceptable data signal is
obtained. Transmitter error correction algorithms, of which this is
an example, may be implemented independently or in combination with
receiver error correction algorithms.
In an example of an error correction technique, the detection of
inverted and non-inverted received data may be used as an indicator
of inductor alignment or misalignment. In the event the receive
coil is outside of the transmit coil, the received data appears to
be inverted. If the receiver is anticipating a specific pattern,
the inverted data results in the receiver failing to recognize the
incoming data. Preferably, the system monitors both the inverted
and non-inverted data stream and corrects for coil misalignment
based on the comparison. At this point, either the receiver or the
transmitter can modify the data stream to restore data
integrity.
FIG. 4 is a diagram illustrating an algorithm for comparing
received data in accordance with an example of a preferred
embodiment of the invention. This algorithm 400 may be implemented
using a computer, signal processing platform, or other programmable
device. Data is transmitted 402 by a suitable transmitter and is
received as a data signal for processing 404. In addition, the data
signal may be manipulated to produce an inverted version of the
data 406. The data may be checked for the presence of errors by
making a comparison 408 of the received data with the inverted
data. If no errors are detected 410 the data may be accepted and
transferred or further processed according to the requirements of
an associated application. In the event a data error is detected,
receiver error correction steps may be implemented 412.
Additionally, transmitter error correction steps may also be taken
414.
While the making and using of various exemplary embodiments of the
invention are discussed herein, it should be appreciated that the
present invention provides inventive concepts which can be embodied
in a wide variety of specific contexts. It should be understood
that the invention may be practiced with power transfer
functionality, such as in battery chargers and AC/DC converters.
For purposes of clarity, detailed descriptions of functions,
components, and systems familiar to those skilled in the applicable
arts are not included. The methods and apparatus of the invention
provide one or more advantages including but not limited to, data
transfer capabilities, managed power transfer capabilities, and
improved converter and charging systems with enhanced energy
utilization and conservation attributes. While the invention has
been described with reference to certain illustrative embodiments,
those described herein are not intended to be construed in a
limiting sense. For example, variations or combinations of steps or
materials in the embodiments shown and described may be used in
particular cases without departure from the invention. Various
modifications and combinations of the illustrative embodiments as
well as other advantages and embodiments of the invention will be
apparent to persons skilled in the arts upon reference to the
drawings, description, and claims.
* * * * *