U.S. patent application number 14/448753 was filed with the patent office on 2015-02-12 for power-over-ethernet (poe) control system.
The applicant listed for this patent is TEXAS INSTRUMENTS INCORPORATED. Invention is credited to JEAN PICARD.
Application Number | 20150042243 14/448753 |
Document ID | / |
Family ID | 52448053 |
Filed Date | 2015-02-12 |
United States Patent
Application |
20150042243 |
Kind Code |
A1 |
PICARD; JEAN |
February 12, 2015 |
POWER-OVER-ETHERNET (PoE) CONTROL SYSTEM
Abstract
One example includes a power-over-Ethernet (PoE) control system.
The system includes a powered device (PD) that is configured to
receive a voltage signal via an Ethernet connection and which
comprises a PoE signal receiver configured to indicate a nominal
power level via the received voltage signal. The system also
includes a power sourcing equipment (PSE) device configured to
generate the voltage signal and to measure a class current of the
voltage signal to determine the nominal power level. The PSE device
includes a PoE controller configured to provide a power setting
command as a function of the nominal power level to the PoE signal
receiver via the voltage signal, such that the PD can operate at a
power level that is based on the power setting command.
Inventors: |
PICARD; JEAN; (Hooksett,
NH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TEXAS INSTRUMENTS INCORPORATED |
Dallas |
TX |
US |
|
|
Family ID: |
52448053 |
Appl. No.: |
14/448753 |
Filed: |
July 31, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61864179 |
Aug 9, 2013 |
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Current U.S.
Class: |
315/307 ;
307/131 |
Current CPC
Class: |
H04L 12/10 20130101;
H05B 47/19 20200101 |
Class at
Publication: |
315/307 ;
307/131 |
International
Class: |
H04L 12/10 20060101
H04L012/10; H05B 37/02 20060101 H05B037/02 |
Claims
1. A power-over-Ethernet (PoE) control system comprising: a powered
device (PD) that is configured to receive a voltage signal via an
Ethernet connection and which comprises a PoE signal receiver
configured to indicate a nominal power level via the received
voltage signal; and a power sourcing equipment (PSE) device
configured to generate the voltage signal and to measure a class
current of the voltage signal to determine the nominal power level,
the PSE device comprising a PoE controller configured to provide a
power setting command as a function of the nominal power level to
the PoE signal receiver via the voltage signal, such that the PD
can operate at a power level that is based on the power setting
command.
2. The system of claim 1, wherein the PSE device is configured to
provide the power setting command as a function of the nominal
power level based on providing the voltage signal as a quantity of
class events associated with a code corresponding to a desired
percentage of the nominal power level.
3. The system of claim 1, wherein the PoE signal receiver is
configured to indicate the nominal power level via a class
signature corresponding to a magnitude of the class current
associated with the voltage signal, wherein the PSE device is
configured to provide the power setting command subsequent to the
PoE signal receiver indicating the nominal power level.
4. The system of claim 3, wherein the class signature has a class
value corresponding to one of a plurality of predetermined nominal
power levels.
5. The system of claim 1, wherein the PoE signal receiver is
configured to provide a first class signature of the class current
in response to a first event classification associated with the
voltage signal, and a second class signature in response to a
second event classification, the second class signature having a
different class value from the first class signature, and a third
class signature in response to a third event classification, with
the third class signature being different from the second class
signature to indicate that the PD has a capacity for PoE control by
the PSE device.
6. The system of claim 5, wherein the third class signature has a
class value that corresponds to one of a plurality of nominal power
levels, such that the third class signature indicates the nominal
power level of the PD to the PSE device.
7. The system of claim 5, wherein the first class signature is
provided from the PD at Class 4, wherein the second class signature
is provided from the PD at Class 5, and wherein the third class
signature is provided from the PD at a class level corresponding to
the nominal power level.
8. The system of claim 1, wherein the PD comprises a first PoE
signal receiver and a second PoE signal receiver, and wherein the
PSE device is configured to provide a first voltage signal to the
first PoE signal receiver and a second voltage signal to the second
PoE signal receiver, wherein the first PoE signal receiver is
configured to provide a first class signature of the class current
in response to a first event classification of the first voltage
signal and wherein the second PoE signal receiver is configured to
provide a second class signature in response to a second event
classification associated with the second voltage signal, wherein
the second class signature has a greater class value from the first
class signature to indicate that the PD has a capacity for PoE
control by the PSE device.
9. The system of claim 8, wherein the second PoE signal receiver is
configured to provide a third class signature in response to a
third event classification associated with the second voltage
signal, wherein the third class signature has a different class
value from the second class signature and wherein the third class
signature is less than the second class signature to indicate that
the PD has a capacity for PoE control by the PSE device, wherein
the third class signature corresponds to the nominal power level to
the PSE device.
10. The system of claim 9, wherein the PSE device is configured to
provide the power setting command as a function of the nominal
power level based on providing at least one of the first and second
voltage signals as a quantity of class events corresponding to a
desired percentage of the nominal power level subsequent to the
indication of the nominal power level via the third class
signature.
11. A PoE lighting system comprising the PoE control system of
claim 1.
12. A method for providing power control in a power-over-Ethernet
(PoE) control system, the method comprising: providing event
classifications of a voltage signal via an Ethernet connection from
a power sourcing equipment (PSE) device; indicating a nominal power
level based on a class signature via a PoE signal receiver of a
powered device (PD) based on a class current of the voltage signal;
providing a power setting command associated with a quantity of
class events of the voltage signal from the PSE device to the PoE
signal receiver, the power setting command corresponding to a
percentage of the nominal power level; and activating the PD to
operate at the percentage of the nominal power level based on the
power setting command.
13. The method of claim 12, further comprising indicating a
capacity for PoE control by the PSE device based on a plurality of
class signatures, wherein indicating the nominal power level
comprises indicating the nominal power level based on a last of the
plurality of class signatures.
14. The method of claim 13, wherein providing the event
classifications comprises providing a first event classification, a
second event classification, and a third event classification,
wherein indicating the capacity for PoE control comprises
indicating the capacity for PoE control by the PSE device based on
a first of the plurality of class signatures provided in response
to the first event classification and a second of the plurality of
class signatures provided in response to the second event
classification, wherein the first and second of the plurality of
class signatures have different class values, and based on a third
of the plurality of class signatures that has a class value that is
less than the second of the plurality of class signatures.
15. The method of claim 12, wherein indicating the nominal power
level comprises indicating the nominal power level based on a value
of the last of the plurality of class signatures corresponding to
one of a plurality of predetermined nominal power levels, wherein
providing the power setting command comprises providing the power
setting command corresponding to a percentage of the one of the
plurality of predetermined nominal power levels.
16. The method of claim 12, wherein providing the event
classifications comprises providing a first event classification
via a first port of the Ethernet connection and providing a second
event classification via a second port of the Ethernet connection,
wherein indicating the nominal power level comprises indicating the
nominal power level based on a first class signature via a first
PoE signal receiver of the PD based on a class current of a first
voltage signal and a second class signature via a second PoE signal
receiver of the PD based on a class current of a second voltage
signal, and wherein providing the power setting command comprises
providing the power setting command associated with a quantity of
class events of at least one of the first voltage signal and the
second voltage signal to a respective at least one of the first PoE
signal receiver and a second PoE signal receiver.
17. A power-over-Ethernet (PoE) control system comprising: a
powered device (PD) that is configured to receive a voltage signal
via an Ethernet connection and which comprises a PoE signal
receiver configured to provide a first class signature in response
to a first event classification via a class current of the received
voltage signal and a second class signature via the class current,
the second class signature having a different class value from the
first class signature, and a third class signature that has a class
value that is less than the second class signature to indicate that
the PD has a capacity for PoE control, the third class signature
indicating a nominal power level of the PD; and a power sourcing
equipment (PSE) device configured to generate the voltage signal
and to measure the class current of the voltage signal to determine
the capacity for PoE control and the nominal power level, the PSE
device comprising a PoE controller configured to provide a power
setting command as a function of the nominal power level to the PoE
signal receiver via the voltage signal, such that the PD can
operate at a power level that is based on the power setting
command.
18. The system of claim 17, wherein the PSE device is configured to
provide the power setting command as a function of the nominal
power level based on providing the voltage signal as a quantity of
class events associated with a code corresponding to a desired
percentage of the nominal power level.
19. The system of claim 17, wherein the PD comprises a first PoE
signal receiver and a second PoE signal receiver, and wherein the
PSE device is configured to provide a first voltage signal to the
first PoE signal receiver and a second voltage signal to the second
PoE signal receiver, wherein the first PoE signal receiver is
configured to provide a first class signature of the class current
in response to a first event classification of the first voltage
signal and wherein the second PoE signal receiver is configured to
provide a second class signature in response to a second event
classification associated with the second voltage signal, wherein
the second class signature is configured to indicate that the PD
has a capacity for PoE control by the PSE device based on being
greater than the first class signature.
20. The system of claim 18, wherein the second PoE signal receiver
is configured to indicate the nominal power level via the third
class signature corresponding to the nominal power level to the PSE
device, and wherein the PSE device is configured to provide the
power setting command as a function of the nominal power level
based on providing at least one of the first and second voltage
signals as a quantity of class events associated with class
signatures corresponding to a desired percentage of the nominal
power level.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Patent Application No. 61/864179, filed Aug. 9, 2013, and entitled
PoE LIGHTING CLASSIFICATION AND CONTROL METHOD, FOUR PAIRS HIGH
POWER, which is incorporated herein by reference in its
entirety.
TECHNICAL FIELD
[0002] This disclosure relates generally to electronic systems, and
more specifically to a power-over-Ethernet (PoE) control
system.
BACKGROUND
[0003] A variety of control systems can be implemented to provide
power and control to power consuming equipment, such as lighting
devices or other types of devices that consume power. One such
control system is Power-over-Ethernet (PoE), such as defined by the
IEEE 802.3at standard, is a manner of safely providing power to a
powered device (PD) over a cable via power sourcing equipment
(PSE), and of removing power if a PD is disconnected. As an
example, the process proceeds through an idle state and three
operational states of detection, classification, and operation.
During detection, the PSE can leave the cable unpowered in the idle
state while it periodically looks to see if a PD has been
plugged-in. The low-power levels that can be used during detection
are unlikely to damage devices not designed for PoE. If a valid PD
signature is present, during classification, the PSE may inquire as
to how much power the PD requires. The PSE may then provide the
required power to the PD if it has sufficient power providing
capacity.
SUMMARY
[0004] One example includes a power-over-Ethernet (PoE) control
system. The system includes a powered device (PD) that is
configured to receive a voltage signal via an Ethernet connection
and which comprises a PoE signal receiver configured to indicate a
nominal power level via the received voltage signal. The system
also includes a power sourcing equipment (PSE) device configured to
generate the voltage signal and to measure a class current of the
voltage signal to determine the nominal power level. The PSE device
includes a PoE controller configured to provide a power setting
command as a function of the nominal power level to the PoE signal
receiver via the voltage signal, such that the PD can operate at a
power level that is based on the power setting command.
[0005] Another example includes a method for providing power
control in a PoE control system. The method includes providing
event classifications of a voltage signal via an Ethernet
connection from a PSE device. The method also includes indicating a
nominal power level based on a class signature via a PoE signal
receiver of a powered device (PD) based on a class current of the
voltage signal. The method also includes providing a power setting
command associated with a quantity of class events of the voltage
signal from the PSE device to the PoE signal receiver. The power
setting command can correspond to a percentage of the nominal power
level. The method further includes activating the PD to operate at
the percentage of the nominal power level based on the power
setting command.
[0006] Another example includes a PoE control system. The system
includes a powered device (PD) that is configured to receive a
voltage signal via an Ethernet connection and which comprises a PoE
signal receiver configured to provide a first class signature in
response to a first event classification via a class current of the
received voltage signal and a second class signature via the class
current, the second class signature having a different class value
from the first class signature, and a third class signature that
has a class value that is less than the second class signature to
indicate that the PD has a capacity for PoE control. The third
class signature can indicate a nominal power level of the PD. The
system further includes a PSE device configured to generate the
voltage signal and to measure the class current of the voltage
signal to determine the capacity for PoE control and the nominal
power level. The PSE device includes a PoE controller configured to
provide a power setting command as a function of the nominal power
level to the PoE signal receiver via the voltage signal, such that
the PD can operate at a power level that is based on the power
setting command.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 illustrates an example of a power-over-Ethernet (PoE)
control system.
[0008] FIG. 2 illustrates another example of a PoE control
system.
[0009] FIG. 3 illustrates an example of a timing diagram.
[0010] FIG. 4 illustrates yet another example of a PoE control
system.
[0011] FIG. 5 illustrates another example of a timing diagram.
[0012] FIG. 6 illustrates an example of a method for providing
power control in a PoE control system.
DETAILED DESCRIPTION
[0013] This disclosure relates generally to electronic systems, and
more specifically to a power-over-Ethernet (PoE) control system. A
PoE control system can include a power sourcing equipment (PSE)
device and a powered device (PD) that are electrically coupled via
an Ethernet connection, such as an RJ-45 cable. As an example, the
PD can correspond to a lighting system or any of a variety of other
electronic devices that consume a varying amount of power. The PSE
device includes a PoE controller and is configured to provide a
voltage signal that can vary in amplitude depending on the phase of
PoE control. The PD can include a PoE signal receiver that is
configured as a current source in response to the voltage signal
provided by the PSE device. The PoE controller can monitor the
class current of the voltage signal to determine class signatures.
In this manner, the PD can include a PoE signal receiver to
indicate to the PSE device that the PD has a capacity for PoE
control, and can indicate a nominal power level of the PD to the
PSE device via the class current of the voltage signal. Therefore,
the PSE device can provide pulses via the voltage signal as a power
setting command to the PD, such that the PD can operate at a power
level that is based on the power setting command.
[0014] For example, subsequent to a detection phase during which
the PSE device determines if the PD is connected, the PSE device
can operate in a classification phase. During the classification
phase, the PSE device can provide the voltage signal at a
classification amplitude to provide event classifications that
include one or more class events and corresponding mark events
(e.g., in a 1-Event or 2-Event classification scheme) via the
voltage signal to the PD, such that the PD can control the class
current of the voltage signal to provide respective class
signatures to the PSE device. As an example, the PD can provide a
first class signature and a second class signature, with the first
and second class signatures being different. Subsequent to the
second class signature, the PD can provide a third class signature
to the PSE device that is less than the second class signature to
indicate the capacity for PoE control by the PSE device. As another
example, the third class signature can indicate a nominal power
level of the PD to the PSE device. For example, the third class
signature can have a value corresponding to one of a plurality of
predetermined nominal power levels, such that the PSE device can
identify the nominal power level based on the value of the third
class signature.
[0015] Subsequent to the indication of the nominal power level, the
PSE device can provide a number of class events that can correspond
to a code corresponding to the power setting command, with the
quantity of pulses corresponding a predetermined percentage of the
nominal power level. As a result, the PSE device can provide the
voltage signal in the activation phase at a maximum amplitude, such
that the PD can operate at the percentage of the nominal power
level based on the power command setting. Accordingly, the PoE
control system described herein can operate to provide physical
(PHY) layer power control of the PD in a simplistic and variable
manner.
[0016] FIG. 1 illustrates an example of a power-over-Ethernet (PoE)
control system 10. The PoE control system 10 can be implemented in
a variety of power-providing applications, such as illumination.
For example, the PoE control system 10 can be implemented to
provide power control via existing Ethernet cables (e.g., RJ-45
cables) without Ethernet data communication capability (e.g.,
utilizing data/link layers, packetization, etc.). Accordingly, as
described herein, the PoE control system 10 provides PoE power
control in a physical (PHY) layer manner.
[0017] The PoE control system 10 includes a power sourcing
equipment (PSE) device 12 and a powered device (PD) 14 that are
electrically coupled via an Ethernet connection 16. As an example,
the Ethernet connection 16 can be an RJ-45 cable that implements
twisted pair conductors (e.g., four twisted pairs). The PSE device
12 is configured to provide a voltage signal V.sub.PORT to the
powered device via the Ethernet connection 16 to implement
bilateral communication between the PSE device 12 and the PD 14.
For example, the voltage V.sub.PORT can correspond to a fixed
voltage V.sub.POE that is generated in the PSE device 12 and which
is modulated in amplitude. As an example, the PD 14 can be
configured as a Type 2 PD according to the IEEE 802.3 standard.
[0018] As described herein, the voltage signal V.sub.PORT can
correspond to a voltage signal that varies to provide event
classifications from the PSE device 12 to the PD 14 in an event
classification scheme, such that the PD 14 can respond to the class
events by varying the current of the voltage signal V.sub.PORT to
provide a class signature to the PSE device 12, such as based on
the IEEE 802.3 standard. As also described herein, the term "event
classification" describes the PSE device 12 providing one or more
class events and corresponding mark events to the PD 14 to provide
communication to and/or to elicit a communication response from the
PD 14 in the form of a class signature. As also described herein,
the term "class event" describes a pulse of the voltage signal
V.sub.PORT at a predetermined amplitude, and which is followed by a
mark event (e.g., decreased voltage subsequent to the pulse) that
signifies an end of the class event. As further described herein,
the term "class signature" refers to a response by the PD 14 of an
event classification that includes the one or more class events in
the form of a magnitude of class current that corresponds to a
class level, described herein as Class 0 through Class 5, with the
class values corresponding to increasing amplitudes of the class
current in ascending order of class value.
[0019] In the example of FIG. 1, the PSE device 12 includes a PoE
controller 18, and the PD 14 includes a PoE signal receiver 20. The
PoE controller 18 can be configured to control an activation time
and an amplitude of the voltage signal V.sub.PORT, such as based on
a given operating phase of the PoE control system 10, to provide
communication to the PD 14. The PoE controller 18 can also be
configured to measure the class current associated with the voltage
signal V.sub.PORT, and thus to determine the class level of a class
signature. The PoE signal receiver 20 can be configured to receive
the voltage signal V.sub.PORT and to act as a class current source
with respect to the voltage signal V.sub.PORT, such that the PoE
signal receiver 20 can adjust the class current of the voltage
signal V.sub.PORT to provide communication to the PSE device 12 in
response to the voltage signal V.sub.PORT. As an example, the PoE
controller 18 can implement the communication with the PoE signal
receiver 20 via a standard, such as IEEE 802.3. For example, the
PoE controller 18 can be configured to provide event
classifications as a 1-Event Physical Layer classification to
provide a single class event, or as a 2-Event Physical Layer
classification to provide a series (e.g., two) of class events
followed by respective mark events. In response, the PD 14 can
provide a corresponding class signature. As described herein, the
term
[0020] As an example, the PSE device 12 can initially operate in a
detection phase, such that the PSE device 12 can provide the
voltage signal V.sub.PORT at a valid test voltage amplitude (e.g.,
between approximately 2.8 volts and approximately 10 volts) at
periodic intervals. If the PD 14 is electrically coupled to the PSE
device 12 via the Ethernet connection 16, the PoE signal receiver
20 can respond by providing a sufficient resistance with respect to
the voltage signal V.sub.PORT to indicate to the PSE device 12 that
the PD 14 is coupled via the Ethernet connection 16. Subsequent to
the detection phase, the PSE device 12 switches to a classification
phase.
[0021] During the classification phase, the PSE device 12 can
provide the voltage signal V.sub.PORT at a classification amplitude
(e.g., between approximately 15.5 volts and approximately 20.5
volts) to provide class events (e.g., 1-Event classifications
and/or 2-Event classifications) via the voltage signal V.sub.PORT
to the PD 14, as controlled by the PoE controller 18. In response
to the class events, the PoE signal receiver 20 can control the
class current of the voltage signal V.sub.PORT to provide
respective class signature to the PSE device 12, such that each
class signature has a range of class current amplitudes that
corresponds to a predetermined Class (e.g., as dictated by IEEE
802.3at). As described previously, the PoE controller 18 can
measure the class current of the voltage signal V.sub.PORT in each
class event, such that the PoE controller 18 can determine the
class signature provided by the PoE signal receiver 20.
Accordingly, as described herein, the PSE device 12 and the PD 14
can communicate with each other.
[0022] As an example, in the classification phase, the PoE signal
receiver 20 can provide a first class signature in response to a
first event classification, followed by a second class signature in
response to a second event classification, and a third class
signature in response to a third event classification. The PoE
signal receiver 20 can provide the second class signature at a
different class (e.g., at a greater current) than the first class
signature, and can provide the third class signature at a class
less than the second class signature to indicate the capacity for
PoE control of the PD 14 by the PSE device 12. For example, the
first class signature can be provided at Class 4 (e.g., in response
to each of two class events of the first event classification), the
second class signature can be provided at Class 5, and the third
class signature can be provided at a range of classes less than
Class 5 (e.g., Class 0-4). As described herein, the term "Class 5"
with respect to a class signature is defined as a class signature
having a higher class current than a Class 4 class signature, such
as implemented in the IEEE 802.3 standard. Therefore, in response
to the values in the sequence of the classes provided by the PoE
signal receiver 20, the PoE controller 18 can identify that the PD
14 has a capacity for PoE control by the PSE device 12.
[0023] In response to a determination of the capacity for PoE
control of the PD 14 by the PSE device 12, the PD 14 can provide an
indication of a nominal power level of the PD 14 to the PSE device
12. As described herein, the nominal power level of the PD 14
corresponds to a maximum power consumption of the PD 14 at full and
normal operating conditions (e.g., full light level for a PoE
lighting system). For example, the third class signature that is
less than the second class signature can have a class value (e.g.,
one of Class 0-4) corresponding to one of a plurality of
predetermined nominal power levels, such that the PoE controller 18
can identify the nominal power level based on the value of the
third class signature. In response to identifying the nominal power
level of the PD 14, the PoE controller 18 can be configured to
control the power level of the PD 14 as a function of the nominal
power level, such that the power output of the PD 14 can be
variably controlled by the PoE controller 18.
[0024] For example, subsequent to the indication of the nominal
power level, the PoE controller 18 can provide a number of class
events via the voltage signal V.sub.PORT associated with a code
corresponding to the power setting command. As an example, the
power setting command can be encoded based on a quantity of pulses
of the class events corresponding to a predetermined percentage of
the nominal power level. In response to the code, the PoE signal
receiver 20 can identify the portion (e.g., percentage) of the
nominal power level that is desired to be output from the PD 14 by
the PoE controller 18. As a result, the PSE device 12 can provide
the voltage signal V.sub.PORT in the activation phase at a maximum
power on amplitude (e.g., between approximately 44 volts and
approximately 57 volts, as dictated by a maximum voltage of an
associated power supply). Therefore, the PD 14 can operate at the
percentage of the nominal power level based on the power command
setting. Accordingly, the PoE control system 10 described herein
can operate to provide PHY layer power control of the PD 14 in a
simplistic and variable manner.
[0025] FIG. 2 illustrates another example of a PoE control system
50. The PoE control system 50 can correspond to the PoE control
system 10 in the example of FIG. 1, such as in a PoE lighting
application. For example, the PoE control system 50 can be
implemented to provide power control via existing Ethernet cables
(e.g., RJ-45 cables) without Ethernet data communication capability
(e.g., utilizing data/link layers, packetization, etc.).
[0026] The PoE control system 50 includes a PSE device 52 and a PD
54 that are electrically coupled via an Ethernet connection 56. In
the example of FIG. 2, the Ethernet connection 56 is demonstrated
as an RJ-45 cable that implements four twisted pair conductors.
Therefore, the Ethernet connection 56 is demonstrated in the
example of FIG. 2 as including two communication ports,
demonstrated as PORT 1 and PORT 2. The PSE device 52 includes a
voltage source 58 that is configured to generate a voltage signal
V.sub.POE. In the example of FIG. 2, the PSE device 52 includes a
PoE controller 60 that provides a voltage control signal P_CTL to
the voltage source 58 to control the amplitude of the voltage
signal V.sub.POE (e.g., depending on the operating phase), and to
measure the class current of the voltage signal V.sub.POE. The PoE
controller 60 is also configured to generate a switching signal SW
to control a set of switches S.sub.1 and S.sub.2 to provide the
voltage signal V.sub.POE and a low-voltage (e.g., ground)
connection, respectively, to the PD 54 via the Ethernet connection
56 as the voltage V.sub.PORT in the example of FIG. 1. Therefore,
in response to the switching signal SW, the voltage signal
V.sub.PORT is provided to the PD 54 based on the voltage V.sub.POE
via each of PORT 1 and PORT 2. Accordingly, the PoE controller 60
can be configured to control an activation time and an amplitude of
the voltage signal V.sub.PORT, such as based on a given operating
phase of the PoE control system 50, to provide communication to the
PD 54. As one example, the voltage signal V.sub.POE can be provided
via the voltage source 58 as the variable voltage V.sub.PORT. As
another example, the voltage signal V.sub.POE can be constant
(e.g., between approximately 44 volts and approximately 57 volts),
and the PSE device 52 can be configured to modulate the impedance
of the switch S .sub.1 to provide the variable voltage V.sub.PORT
provided to the PD 54.
[0027] In the example of FIG. 2, the PD 54 includes a pair of
rectifiers 62 that are each coupled to the Ethernet connection 56
at the respective ports PORT 1 and PORT 2. The rectifiers 62 are
configured to provide the voltage signal V.sub.PORT across a
capacitor C.sub.PD. In the example of FIG. 2, the PD 54 includes a
PoE signal receiver 64 ("PoE RX") that receives a voltage V.sub.P
corresponding to the voltage signal V.sub.PORT across the capacitor
C.sub.PD. The PoE signal receiver 64 thus receives the voltage
V.sub.P and acts as a current source with respect to the voltage
V.sub.P, and thus the voltage signal V.sub.PORT, such that the PoE
signal receiver 64 can adjust the class current of the voltage
signal V.sub.PORT to provide communication to the PSE device 52 in
response to the voltage signal V.sub.PORTIn addition, the PD 54
includes a power controller 66 to which the PoE signal receiver 64
can provide a control signal CTRL. Therefore, in response to a
power setting command provided to the PoE signal receiver 64 by the
PoE controller 60, the PoE signal receiver 64 can indicate a
desired output power level, such as being a function (e.g.,
percentage) of the nominal power level of the PD 54, to the power
controller 66 via the control signal CTRL. Accordingly, during the
activation phase described in greater detail herein, the power
controller 66 can provide the desired output power dictated by the
power setting command in response to the full amplitude of the
voltage signal V.sub.PORT provided by the PSE device 52.
[0028] FIG. 3 illustrates an example of a timing diagram 100. The
timing diagram 100 demonstrates an amplitude of the voltage signal
V.sub.P as a function of time. The timing diagram 100 can
correspond to operation of the PoE control system 50. Therefore,
reference is to be made to the example of FIG. 2 in the following
description of the example of FIG. 3.
[0029] Prior to a time T.sub.0, the voltage signal V.sub.P can have
an amplitude V.sub.MIN, corresponding to a substantially minimum
voltage (e.g., zero volts). As an example, the amplitude V.sub.MIN
could correspond to an actual voltage amplitude of the voltage
signal V.sub.P, or could correspond to the switches S.sub.1 and
S.sub.2 being open. At the time T.sub.0, the PSE device 52 can
begin operating in a detection phase, such that the voltage signal
V.sub.P increases to a low amplitude V.sub.VALID1 (e.g., between
approximately 2.8 volts and approximately 10 volts). Since the PD
54 is electrically coupled to the PSE device 52 via the Ethernet
connection 56, the PoE signal receiver 64 can respond by providing
a sufficient resistance with respect to the voltage signal V.sub.P
to indicate to the PSE device 52 that the PD 54 is coupled via the
Ethernet connection 56. At a time T.sub.1, the voltage signal
V.sub.P decreases to an amplitude V.sub.VALID2 (e.g., also between
approximately 2.8 volts and approximately 10 volts, but different
(e.g., less) than the amplitude V.sub.VALID1). Therefore, the PSE
device 52 can determine the resistance value of the PoE signal
receiver 64 based on a .DELTA.I/.DELTA.V of the separate amplitudes
V.sub.VALID1 and V.sub.VALID2. At a time T.sub.2, the amplitude
V.sub.MIN, thus concluding the detection phase. While the detection
phase is demonstrated in the example of FIG. 3 as including only a
single differential measurement of the voltage signal V.sub.P at
the amplitudes V.sub.VALID1 and V.sub.VALID2, it is to be
understood that the detection phase could include differential
measurements and/or additional amplitudes in the detection phase
voltage amplitude range, such as dictated by the IEEE 802.3at
standard.
[0030] At the time T.sub.3, the PSE device 52 switches to a
classification phase, during which the PoE controller 60 can
determine whether the PD 54 has a capacity for PoE control, can
determine a nominal power level of the PD 54, and can provide a
power setting command to the PoE signal receiver 64. Beginning at
the time T.sub.3, the PSE device 52 provides a first event
classification, demonstrated at 102 as a 2-Event classification. At
the time T.sub.3, the voltage signal V.sub.P is provided at an
amplitude V.sub.CLASS in a first class event. The amplitude
V.sub.CLASS can correspond to a voltage amplitude in a
classification amplitude range amplitude (e.g., between
approximately 15.5 volts and approximately 20.5 volts). In response
to receiving the voltage signal V.sub.P of the first class event at
the time T.sub.3 (e.g., via the voltage V.sub.P), the PoE signal
receiver 64 can indicate a first class value (e.g., Class 4). At a
time T.sub.4, the voltage signal V.sub.P can decrease to an
amplitude V.sub.MRK, corresponding to a mark event. As an example,
the mark event can signify to the PoE signal receiver 64 the end of
the first class event. Similarly, at a time T.sub.5, the PSE device
52 provides the voltage signal V.sub.P at the amplitude V.sub.CLASS
in a second class event of the first event classification (e.g., of
the 2 Event classification), in response to which the PoE signal
receiver 64 can provide a second class value (e.g., Class 4),
followed by another mark event at a time T.sub.6. As an example,
the first and second class values can be equal (e.g., Class 4).
Thus, the PD 14 can respond to the first event classification with
a class signature that comprises two Class 4 current responses to
the respective two class events of the first event classification
102. The example of FIG. 3 demonstrates that the first event
classification 102 comprises two class events in a 2-Event
classification scheme, such as to ensure a linear response to a
substantially constant amplitude of the voltage signal V.sub.P at
the classification amplitude range. However, it is to be understood
that the PoE controller 60 can be configured to provide the first
event classification as a 1-Event classification by providing a
single class event, or based on providing more than two class
events.
[0031] At a time T.sub.7, the PSE device 52 again provides the
voltage signal V.sub.P at an amplitude V.sub.CLASS in a second
event classification (e.g., a 1-Event classification), demonstrated
at 104. In response to receiving the voltage signal V.sub.P in a
class event of the second event classification 104 (e.g., via the
voltage V.sub.P), the PoE signal receiver 64 can provide a second
class signature (e.g., Class 5). At a time T.sub.8, the voltage
signal V.sub.P can decrease to the amplitude V.sub.MRK,
corresponding to a mark event of the second event classification
104, thus signifying to the PoE signal receiver 64 the end of the
class event of the second event classification 104. The second
class signature can be provided by the PoE signal receiver 64 at a
value that is different from (e.g., greater than) the first class
signature, thus potentially signifying to the PoE controller 60
that the PD 54 may have a capacity for PoE control.
[0032] At a time T.sub.9, the PSE device 52 again provides the
voltage signal V.sub.P at an amplitude V.sub.CLASS in a third event
classification, demonstrated at 106. In response to receiving the
voltage signal V.sub.P in the third event classification 106 (e.g.,
via the voltage V.sub.P), the PoE signal receiver 64 can provide a
third class signature at a value that is less than the second class
signature (e.g., Class 0-4). At a time T.sub.10, the voltage signal
V.sub.P can decrease to the amplitude V.sub.MRK, corresponding to a
mark event, thus signifying to the PoE signal receiver 64 the end
of the third event classification 106. The third class signature
can be provided by the PoE signal receiver 64 at a value that is
less than the second class signature to indicate to the PoE
controller 60 that the PD 54 has a capacity for PoE control. In
addition, the specific class value of the third class signature 106
can indicate to the PoE controller 60 the nominal power level of
the PD 54. For example, the class value of the third class
signature can correspond to one of a plurality of predetermined
nominal power levels, such that the PoE controller 60 can identify
the nominal power level based on the value of the third class
signature, such as provided in Table 1 below:
TABLE-US-00001 TABLE 1 Third Class Nominal Power Signature Value
Level of the PD 54 0 15 W 1 30 W 2 45 W 3 60 W 4 90 W
The predetermined nominal power levels demonstrated in the example
of Table 1 are provided only by example, in that any of a variety
of other predetermined nominal power levels can be provided in the
communication from the PoE signal receiver 64 to the PoE controller
60 via the third class signature.
[0033] As described previously, in response to identifying the
nominal power level of the PD 54, the PoE controller 60 can be
configured to control the power level of the PD 54 as a function of
the nominal power level, such that the power output of the PD 54
can be variably controlled by the PoE controller 60. At a time
T.sub.11, the PoE controller 60 can begin to provide a number of
event classifications (e.g., 1-Event classifications) via the
voltage signal V.sub.P associated with a code corresponding to the
power setting command. As an example, the power setting command can
be encoded based on a quantity of class events corresponding to a
predetermined percentage of the nominal power level, such as
provided in Table 2 below:
TABLE-US-00002 Quantity of Class Percentage of Events Nominal Power
Level 0 100% 1 80% 2 55% 3 30%
[0034] The predetermined percentage values of the nominal power
level demonstrated in the example of Table 2 are provided only by
example, in that the PoE controller 60 can be configured to provide
any of a variety of predetermined quantities corresponding to
associated percentages of nominal power level. The example of FIG.
3 demonstrates a single class event with associated mark event
subsequently at the time T.sub.11. However, it is to be understood
that the PoE controller 60 can be configured to provide zero class
events to signify a desired power level of the PD 54.
[0035] In response to the code, the PoE signal receiver 64 can
identify the percentage of the nominal power level that is desired
to be output from the PD 54 by the PoE controller 60. As a result,
at a time T.sub.12, the PSE device 52 begins operating in the
activation phase, and thus provides the voltage signal V.sub.P at a
maximum amplitude V.sub.PORT.sub.--.sub.PSE (e.g., between
approximately 44 volts and approximately 57 volts, as dictated by a
maximum voltage of an associated power supply). Therefore, the PD
54 can operate at the percentage of the nominal power level based
on the power command setting. Accordingly, the PoE control system
50 described herein can operate to provide PHY layer power control
of the PD 54 in a simplistic and variable manner.
[0036] FIG. 4 illustrates yet another example of a PoE control
system 150. The PoE control system 150 can correspond to the PoE
control system 10 in the example of FIG. 1, such as in a PoE
lighting application. For example, the PoE control system 150 can
be implemented to provide power control via existing Ethernet
cables (e.g., RJ-45 cables) without Ethernet data communication
capability (e.g., utilizing data/link layers, packetization,
etc.).
[0037] The PoE control system 150 includes a PSE device 152 and a
PD 154 that are electrically coupled via an Ethernet connection
156. In the example of FIG. 4, the Ethernet connection 156 is
demonstrated as an RJ-45 cable that implements four twisted pair
conductors. Therefore, the Ethernet connection 156 is demonstrated
in the example of FIG. 4 as including two communication ports,
demonstrated as PORT 1 and PORT 2. The PSE device 152 includes a
voltage source 158 that is configured to generate a variable
voltage signal V.sub.POE. Similar to as described previously in the
example of FIG. 3, the PSE device 152 can provide the voltage
V.sub.POE in a variable manner as the voltage V.sub.PORT across the
Ethernet connection 156.
[0038] In the example of FIG. 4, the PSE device 152 includes a PoE
controller 160 that provides a voltage control signal P_CTL to the
voltage source 158 to control the amplitude of the voltage signal
V.sub.POE (e.g., depending on the operating phase), and to measure
the class current of the voltage signal V.sub.PORT. The PoE
controller 160 is also configured to generate a pair of switching
signals SW.sub.1 and SW.sub.2 to control a respective set of
switches S.sub.1 and S.sub.2 to provide the voltage signal
V.sub.POE and a low-voltage (e.g., ground) connection,
respectively, to the PD 154 via the Ethernet connection 156.
Therefore, in response to the switching signal SW.sub.1, the
voltage signal V.sub.PORT is provided to the PD 154 via PORT 1, and
in response to the switching signal SW.sub.2, the voltage signal
V.sub.PORT is provided to the PD 154 via PORT 2. Accordingly, the
PoE controller 160 can be configured to control an activation time
and an amplitude of the voltage signal V.sub.PORT on each of PORTS
1 and 2 individually, such as based on a given operating phase of
the PoE control system 150, to provide communication to the PD
154.
[0039] In the example of FIG. 4, the PD 154 includes a first
rectifier 162 that is coupled to the Ethernet connection 156 at
PORT 1 and a second rectifier 163 that is coupled to the Ethernet
connection 156 at PORT 2. The first rectifier 162 is configured to
provide the voltage signal V.sub.PORT across a first capacitor
C.sub.PD1 and the second rectifier 163 is configured to provide the
voltage signal V.sub.PORT across a second capacitor C.sub.PD2. In
the example of FIG. 4, the PD 154 includes a first PoE signal
receiver 164 ("PoE RX1") that receives a voltage V.sub.P1
corresponding to the voltage signal V.sub.PORT across the first
capacitor C.sub.PD1 and a second PoE signal receiver 165 ("PoE
RX2") that receives a voltage V.sub.P2 corresponding to the voltage
signal V.sub.PORT across the second capacitor C.sub.PD2.
[0040] The first PoE signal receiver 164 thus receives the voltage
VPD1 and acts as a current source with respect to the voltage VPD1,
and thus the voltage signal V.sub.PORT, such that the first PoE
signal receiver 164 can adjust the class current of the voltage
signal V.sub.PORT to provide communication to the PSE device 152 in
response to the voltage signal V.sub.PORTSimilarly, the second PoE
signal receiver 165 thus receives the voltage VPD2 and acts as a
current source with respect to the voltage VPD2, and thus the
voltage signal V.sub.PORT, such that the second PoE signal receiver
164 can adjust the class current of the voltage signal V.sub.PORT
to provide communication to the PSE device 152 in response to the
voltage signal V.sub.PORTIn addition, the PD 154 includes a power
controller 166 to which the first and second PoE signal receivers
164 and 165 can provide respective control signals CTRL1 and CTRL2.
Therefore, in response to a power setting command provided to at
least one of the PoE signal receivers 164 and 165 by the PoE
controller 160, the PoE signal receiver(s) 164 and 165 can indicate
a desired output power level, such as being a function (e.g.,
percentage) of the nominal power level of the PD 154, to the power
controller 166 via the control signal(s) CTRL1 and CTRL2.
Accordingly, during the activation phase described in greater
detail herein, the power controller 166 can provide the desired
output power dictated by the power setting command in response to
the full amplitude of the voltage signal V.sub.PORT provided by the
PSE device 152.
[0041] FIG. 5 illustrates an example of timing diagrams 200 and
201. The timing diagram 200 demonstrates an amplitude of the
voltage V.sub.P1 as a function of time, and the timing diagram 201
demonstrates an amplitude of the voltage V.sub.P2 as a function of
time. The timing diagrams 200 and 201 can correspond to operation
of the PoE control system 150. Therefore, reference is to be made
to the example of FIG. 4 in the following description of the
example of FIG. 5. Thus, the voltage V.sub.P1 corresponds to the
voltage V.sub.PORT in response to activation of the switch S.sub.1
via the switching signal SW.sub.1, and voltage V.sub.P2 corresponds
to the voltage V.sub.PORT in response to activation of the switch
S.sub.2 via the switching signal SW.sub.2.
[0042] Prior to a time T.sub.0, the voltages V.sub.P1 and V.sub.P2
can each have an amplitude V.sub.MIN, corresponding to a
substantially minimum voltage (e.g., zero volts). As an example,
the amplitude V.sub.MIN could correspond to an actual voltage
amplitude of the voltages V.sub.P1 and V.sub.P2, or could
correspond to the switches S.sub.1 and S.sub.2 being open. At the
time T.sub.0, the PSE device 152 can begin operating in a detection
phase, such that the voltage V.sub.P1 increases to the amplitude
V.sub.VALID1. Since the PD 154 is electrically coupled to the PSE
device 152 via the Ethernet connection 156, the first PoE signal
receiver 164 can respond by providing a sufficient resistance with
respect to the voltage V.sub.P1 to indicate to the PSE device 152
that the PD 154 is coupled via the Ethernet connection 156. At a
time T.sub.1, the voltage V.sub.P1 decreases to an amplitude
V.sub.VALID1, while the voltage V.sub.P2 increases to the amplitude
V.sub.VALID1. At a time T.sub.2, the voltage V.sub.P1 decreases
back to the amplitude V.sub.MIN. Similarly, at a time T.sub.2, the
voltage V.sub.P2 decreases to the amplitude V.sub.VALID2. Since the
PD 154 is electrically coupled to the PSE device 152 via the
Ethernet connection 156, the second PoE signal receiver 165 can
respond by providing a sufficient resistance with respect to the
voltage V.sub.P2 to indicate to the PSE device 152 that the PD 154
is coupled via the Ethernet connection 156. Therefore, the PSE
device 152 can determine the resistance value of the PoE signal
receivers 164 and 165 based on a .DELTA.I/.DELTA.V of the separate
amplitudes V.sub.VALID1 and V.sub.VALID2. At a time T.sub.3, the
voltage V.sub.P2 decreases back to the amplitude V.sub.MIN, thus
concluding the detection phase, based on which the PoE controller
160 identifies that both PORT 1 and PORT 2 are coupled to the
respective first and second PoE signal receivers 164 and 165. While
the detection phase is demonstrated in the example of FIG. 5 as
including only a single pulse of the voltages V.sub.P1 and V.sub.P2
at the single amplitude V.sub.VALID, it is to be understood that
the detection phase could include additional pulses and/or
additional amplitudes in the detection phase voltage amplitude
range, such as dictated by the IEEE 802.3at standard, for each of
the voltages V.sub.P1 and V.sub.P2.
[0043] At the time T.sub.4, the PSE device 152 switches to a
classification phase, during which the PoE controller 160 can
determine whether the PD 154 has a capacity for PoE control, can
determine a nominal power level of the PD 154, and can provide a
power setting command to the PoE signal receiver(s) 164 and 165.
Beginning at the time T.sub.4, the PSE device 152 provides a first
event classification to the first PoE signal receiver 164,
demonstrated at 102 as a 2-Event classification. Thus, at the time
T.sub.4, the voltage V.sub.P1 increases to an amplitude V.sub.CLASS
in a first class event. The amplitude V.sub.CLASS can correspond to
a voltage amplitude in a classification amplitude range amplitude
(e.g., between approximately 15.5 volts and approximately 20.5
volts). In response to the increase of the voltage V.sub.P1 of the
first class event in the first event classification 202, the PoE
signal receiver 164 can provide a first class value (e.g., Class
4). At a time T.sub.5, the voltage V.sub.P1 can decrease to an
amplitude V.sub.MRK, corresponding to a mark event. As an example,
the mark event can signify to the first PoE signal receiver 164 the
end of the first class event of the event classification 202.
Similarly, at a time T.sub.6, the voltage V.sub.P1 increases to the
amplitude V.sub.CLASS in a second class event of the event
classification 202, in response to which the PoE signal receiver 64
can provide a second class value (e.g., Class 4), followed by
another mark event at a time T.sub.7. As an example, the first and
second initial class values can be equal (e.g., Class 4). Thus, the
first PoE receiver 164 can respond to the first event
classification with a class signature that comprises two Class 4
current responses to the respective two class events of the first
event classification 202. The example of FIG. 5 demonstrates that
the first event classification 202 comprises two class events in a
2-Event classification scheme, such as to ensure a linear response
to a substantially constant amplitude of the voltage signal
V.sub.PORT at the classification amplitude range. However, it is to
be understood that the PSE device 152 can be configured to provide
the first event classification as a 1-Event classification by
providing a single class event, or based on providing more than two
class events.
[0044] At a time T.sub.8, the PSE device 152 provides a second
event classification via PORT 2, demonstrated at 204, at which the
voltage V.sub.P2 increases to an amplitude V.sub.CLASS in a class
event at the time T.sub.8. In response to the class event of the
second event classification 204, the second PoE signal receiver 165
can provide a second class signature (e.g., Class 5). At a time
T.sub.9, the voltage V.sub.P2 can decrease to the amplitude
V.sub.MRK, corresponding to a mark event, thus signifying to the
second PoE signal receiver 165 the end of the class event of the
event classification 204. The second class signature can be
provided by the second PoE signal receiver 165 at a value that is
different from the first class signature, thus potentially
signifying to the PoE controller 160 that the PD 154 may have a
capacity for PoE control.
[0045] At a time T.sub.10, the PSE device 152 provides a third
event classification via PORT 2, demonstrated at 206, at which the
voltage V.sub.P2 increases to the amplitude V.sub.CLASS in a class
event at the time T.sub.10. In response to the class event of the
third event classification 206, the second PoE signal receiver 166
can provide a third class signature that is less than the second
class signature (e.g., Class 0-4). At a time T.sub.11, the voltage
V.sub.P2 can decrease to the amplitude V.sub.MRK, corresponding to
a mark event, thus signifying to the second PoE signal receiver 165
the end of the class event of the third event classification 206.
The third class signature can be provided by the second PoE signal
receiver 166 at a value that is less than the second class
signature to indicate to the PoE controller 160 that the PD 154 has
a capacity for PoE control. In addition, the specific class value
of the third class signature 206 can indicate to the PoE controller
160 the nominal power level of the PD 154, such as demonstrated
previously in Table 1.
[0046] As described previously, in response to identifying the
nominal power level of the PD 154, the PoE controller 160 can be
configured to control the power level of the PD 154 as a function
of the nominal power level, such that the power output of the PD
154 can be variably controlled by the PoE controller 160. At a time
T.sub.11, the PoE controller 160 can begin to provide a number of
class events via one or both of the voltages V.sub.P1 and V.sub.P2
associated with a code corresponding to the power setting command.
As an example, the power setting command can be encoded based on a
quantity of pulses of the class events corresponding to a
predetermined percentage of the nominal power level, such as
provided previously in Table 2. As an example, the additional class
events that indicate the percentage of nominal power level can be
provided solely via the voltage V.sub.P1, solely via the voltage
V.sub.P2, or based on a combination of the voltages V.sub.P1 and
V.sub.P2. For example, the code can be based on a sum of the
quantity of class events provided via the voltages V.sub.P1 and
V.sub.P2, or the code can be based on a binary and/or time-based
encoding of the class events provided via the voltages V.sub.P1 and
V.sub.P2. Thus, the additional class events that indicate the
percentage of nominal power level can be provided in any of a
variety of ways.
[0047] In response to the code, the first and/or second PoE signal
receivers 164 and 165 can identify the percentage of the nominal
power level that is desired to be output from the PD 154 by the PoE
controller 160. As a result, at a time T.sub.13, the PSE device 152
begins operating in the activation phase, and thus provides the
voltage signal V.sub.PORT at a maximum amplitude to provide the
voltages V.sub.P1 and/or V.sub.P2 at the amplitude
V.sub.PORT.sub.--.sub.PSE. Therefore, the PD 154 can operate at the
percentage of the nominal power level based on the power command
setting. Accordingly, the PoE control system 150 described herein
can operate to provide PHY layer power control of the PD 154 in a
simplistic and variable manner over multiple ports via the Ethernet
connection 156.
[0048] In view of the foregoing structural and functional features
described above, a method in accordance with various aspects of the
present invention will be better appreciated with reference to FIG.
6. While, for purposes of simplicity of explanation, the method of
FIG. 6 is shown and described as executing serially, it is to be
understood and appreciated that the present invention is not
limited by the illustrated order, as some aspects could, in
accordance with the present invention, occur in different orders
and/or concurrently with other aspects from that shown and
described herein. Moreover, not all illustrated features may be
required to implement a method in accordance with an aspect of the
present invention.
[0049] FIG. 6 illustrates an example of a method 250 for providing
power control in a PoE control system. At 252, event
classifications (e.g., event classifications 102, 104, and 106) of
a voltage signal (e.g., the voltage signal V.sub.PORT) are provided
via an Ethernet connection (e.g., the Ethernet connection 16) from
a PSE device (e.g., the PSE device 12). At 254, a nominal power
level is indicated based on a class signature (e.g., the class
signature 106) via a PoE signal receiver (e.g., the PoE signal
receiver 20) of a powered device (e.g., the PD 14) based on a class
current of the voltage signal. At 256, a power setting command
associated with a quantity of class events of the voltage signal
(e.g., at the time T.sub.11 in the example of FIG. 3) is provided
from the PSE device to the PoE signal receiver. The power setting
command can correspond to a percentage of the nominal power level
(e.g., Table 1). At 258, the PD is activated to operate at the
percentage of the nominal power level based on the power setting
command.
[0050] What have been described above are examples of the
invention. It is, of course, not possible to describe every
conceivable combination of components or method for purposes of
describing the invention, but one of ordinary skill in the art will
recognize that many further combinations and permutations of the
invention are possible. Accordingly, the invention is intended to
embrace all such alterations, modifications, and variations that
fall within the scope of this application, including the appended
claims.
* * * * *