Note: Descriptions are shown in the official language in which they were submitted.
WIRELESSLY DETECTABLE OBJECT THAT EMITS
A VARIABLE-FREQUENCY RESPONSE SIGNAL, AND
METHOD AND SYSTEM FOR DETECTING AND LOCATING SAME
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of and priority to U.S.
Provisional Patent Application Serial No. 62/741,274 filed October 4, 2018,
the
entire disclosure of which is incorporated by reference herein.
TECHNICAL FIELD
The present disclosure generally relates to wirelessly detectable
objects, and more particularly to wirelessly detectable objects that may emit
a
variable frequency response signal upon receiving an interrogation signal.
Such may be used to mark objects used in medical procedures or may take the
form of objects used in medical procedures, for instance sponges, gauze, or
instruments.
BACKGROUND
Description of the Related Art
It is often useful or important to be able to determine the presence
or absence of an object.
For example, it is important to determine whether objects
associated with surgery are present in a patient's body before completing the
surgery. Such objects may take a variety of forms, such as, for example,
instruments, for instance scalpels, scissors, forceps, hemostats, and/or
clamps.
Also for example, the objects may take the form of related accessories and/or
disposable objects, for instance surgical sponges, gauzes, and/or pads.
Failure
to locate an object before closing the patient may require additional surgery,
and in some instances may have serious adverse medical consequences.
Some hospitals have instituted procedures that include checklists
or require multiple counts be performed to track the use and return of objects
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during surgery. Such manual approaches are inefficient, require the time of
highly trained personnel, and are prone to error.
Another approach employs automation using wireless
transponders and an interrogation unit that may include a transceiver. An
automated system may advantageously increase accuracy while reducing the
amount of time required of highly trained and highly compensated personnel.
Such an approach may employ passive wireless transponders which are
attached to various objects used during surgery. The transceiver may emit
wireless signals (e.g., radio or microwave frequency) which power the
transponders. The transceiver may detect wireless signals returned by the
transponders in response. Some implementations employ wireless
transponders that store and return a unique identifier. These wireless
transponders are often referred to as radio frequency identification (RFID)
transponders or tags. Other implementations employ transponders that do not
store or return a unique identifier, but rather return (e.g., backscatter) a
signal
that indicates a presence of the wireless transponder without uniquely
identifying the specific wireless transponder. Systems employing dumb
wireless transponders typically have better range and, or, ability to detect
wireless transponder tagged objects within body tissue as compared to systems
employing RFID wireless transponders. Such can be particular advantageous,
for instance where a patient is obese. Examples an approach employing dumb
wireless transponders are discussed in U.S. Patent No. 6,026,818, issued
February 22, 2000, and U.S. Patent Publication No. US 2004/0250819,
published December 16, 2004.
BRIEF SUMMARY
However, some of these approaches do not allow identification of
a specific object, for example from a collection of similar objects. For
instance,
approaches employing dumb wireless transponders typically cannot identify a
particular or specific lap sponge from a group of lap sponges. Conventional
approaches that allow identification of the object via transmitting an
identifier
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1
typically transmit a signal at frequencies that have a short range of
detection,
which may inhibit detection of the transponder, and thus, the object attached
thereto. Furthermore, these transponders may not be detectable by the
interrogation device when they are situated such that there is an obstacle or
membrane, such skin or flesh, between the transponder and the interrogation
device. In addition, some of these approaches may be susceptible to
interference from noise, which may result in the response signal transmitted
from the transponder not being detected by the interrogation unit.
Consequently, a new approach to uniquely identify and robustly
detect the presence and absence of a transponder assembly as well as
identification is desirable.
A wirelessly detectable object may be summarized as including:
at least one antenna; a passive variable-frequency transponder circuit that is
communicatively coupled to the at least one antenna, the passive variable-
frequency transponder circuit powered by an interrogation signal received via
the at least one antenna from an external source, and operable to return a
wireless response signal via the at least one antenna, the response signal
having a frequency that varies over a single interrogation cycle to produce a
characteristic signature in the wireless response signal.
The passive variable-frequency transponder circuit may include at
least one inductor and at least one varactor diode, the varactor diode which
has
a variable capacitance that depends at least in part on a control voltage, the
frequency of the wireless response signal which varies based at least in part
on
the variable capacitance of the varactor diode. The passive variable-frequency
transponder circuit may generate a response voltage upon receiving the
interrogation signal, the response voltage which decreases when the
interrogation signal is removed from the passive variable-frequency
transponder circuit, and wherein the control voltage for the variable
capacitance
in the varactor diode depends at least in part upon the response voltage. The
variable capacitance of the varactor diode may vary inversely with the control
voltage. The frequency of the wireless response signal may vary inversely with
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respect to the variable capacitance. The at least one inductor may include a
plurality of coils, each coil which extends in a direction different from the
directions in which each of the other respective coils extends. Each of the
plurality of coils may extend at a right angle with respect to the direction
at
which each of the other respective coils extends. Each of the plurality of
coils
may include ferrite. The passive variable-frequency transponder circuit may
include at least one inductor, a first capacitor, and a switch, the switch
which is
operable to selectively electrically couple and decouple at least a second
capacitor to the other components of the passive variable-frequency
transponder circuit, in which the wireless response signal returned via the
antenna has a first frequency when the second capacitor is electrically
coupled
to the resonant circuit and has a second frequency when the second capacitor
is decoupled from the resonant circuit. The second frequency may be lower
than the first frequency. The switch may include one or more transistors. The
.. at least one inductor may include a plurality of coils, each coil which
extends in
a direction different from the directions in which each of the other
respective
coils extends. Each of the plurality of coils may extend at a right angle with
respect to the direction at which each of the other respective coils extends.
The
at least one antenna may include a first antenna and a second antenna, and
wherein the passive variable-frequency transponder circuit includes at least a
first resonant circuit that is electrically communicatively coupled to the
first
antenna, and a second resonant circuit that is communicatively coupled to the
first resonant circuit and to the second antenna, wherein the first resonant
circuit is powered by the interrogation signal received via the first antenna
and
generates a first signal of a first frequency in response, wherein the second
resonant circuit is powered by the first signal and generates a second signal
of
a second frequency in response, and wherein the response signal returned by
the second antenna includes at least one of the first signal and the second
signal. The second antenna may be further communicatively coupled to the
first resonant circuit, wherein the response signal returned by the second
antenna may include at least the first signal and the second signal. The
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response signal may include only the second signal. In operation, the first
resonant circuit may receive the interrogation signal during a first time
period
and the second antenna may generate the response signal during a second
time period, the first time period which at least partially overlaps with the
.. second time period. The wirelessly detectable object may further include: a
pouch with an interior cavity, the passive variable-frequency transponder
circuit
which is received within the interior cavity of the pouch. The wirelessly
detectable object may further include: a piece of absorbent material, wherein
the pouch is physically coupled to at least a portion of the piece of
absorbent
material. The piece of absorbent material may be at least one of a surgical
sponge and surgical gauze. The wirelessly detectable object may further
include: a piece of absorbent material, the passive variable-frequency
transponder circuit which is physically coupled to the piece of absorbent
material. The piece of absorbent material may be at least one of a surgical
sponge and surgical gauze.
A system to detect a wirelessly detectable object may be
summarized as including: the wirelessly detectable object, the wirelessly
detectable object which includes at least one antenna; and a passive variable-
frequency transponder circuit that is communicatively coupled to the at least
one antenna, the passive variable-frequency transponder circuit powered by an
interrogation signal received via the at least one antenna from an external
source, and operable to return a wireless response signal via the at least one
antenna, the response signal having a frequency that varies over a single
interrogation cycle to produce a characteristic signature in the wireless
response signal; and a transceiver, the transceiver which includes at least
one
antenna, the least one antenna from the transceiver which emits the
interrogation signal and receives the response signal.
The system may further include: a processor that is
communicatively coupled to the transceiver, the processor which executes one
or more instructions that cause the transceiver to receive the response signal
from the at least one antenna in the transceiver and to determine a distance
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from the transceiver to the wirelessly detectable object based at least in
part
upon the received response signal. The processor may further determine the
distance from the transceiver to the wirelessly detectable object based at
least
in part upon the emitted interrogation signal. The distance between the
transceiver and the wirelessly detectable object may include a distance range.
The transceiver may be a wand.
A method of operation of a wirelessly detectable object may be
summarized as including: receiving an interrogation signal via at least one
antenna from an external source; powering by the interrogation signal a
passive
variable-frequency transponder circuit that is communicatively coupled to the
at
least one antenna; and returning by the passive variable-frequency transponder
circuit a wireless response signal via the at least one antenna, the wireless
response signal having a frequency that varies over a signal interrogation
cycle
to produce a characteristic signature in the wireless response signal.
The passive variable-frequency transponder circuit may include at
least one inductor and at least one varactor diode having a variable
capacitance, and wherein powering the passive variable-frequency transponder
circuit may include varying the frequency of the wireless response signal
based
at least upon varying the capacitance of the at least one varactor diode. The
passive variable-frequency transponder circuit may include at least one
inductor, a first capacitor, and a switch, and wherein powering the passive
variable-frequency transponder circuit may include selectively electrically
coupling and decoupling at least a second capacitor to the other components of
the passive variable-frequency transponder circuit.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
In the drawings, identical reference numbers identify similar
elements or acts. The sizes and relative positions of elements in the drawings
are not necessarily drawn to scale. For example, the shapes of various
elements and angles are not drawn to scale, and some of these elements are
arbitrarily enlarged and positioned to improve drawing legibility. Further,
the
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particular shapes of the elements as drawn, are not intended to convey any
information regarding the actual shape of the particular elements, and have
= been solely selected for ease of recognition in the drawings.
Figure 1 shows a system that includes a transceiver and a
wirelessly detectable object, in which the transceiver may emit an
interrogation
signal that may be received by the wirelessly detectable object, and the
wirelessly detectable object may return in response a variable-frequency
response signal, according to at least one illustrated implementation.
Figure 2A is a schematic diagram of a wirelessly detectable object
that includes an antenna and a passive variable-frequency transponder circuit
that includes a varactor diode, according to at least one illustrated
implementation.
Figure 2B is a schematic diagram of a wirelessly detectable object
that includes an antenna and a variable-frequency transponder circuit that
includes a capacitor that may be selectively, electrically coupled to the
other
components in the wirelessly detectable object, according to at least one
illustrated implementation.
Figure 3A is a schematic diagram of a wirelessly detectable object
that includes a first resonant circuit that is electrically coupled to a
second
resonant circuit, in which the first resonant circuit is powered by an
interrogation
signal received via a first antenna, the first resonant circuit provides an
output
that powers the second resonant circuit, and the second antenna emits a
response signal comprised of an output signal received from the second
resonant circuit, according to at least one illustrated implementation.
Figure 3B is a schematic diagram of a wirelessly detectable object
that includes a first resonant circuit that is electrically coupled to a
second
resonant circuit, in which the first resonant circuit is powered by an
interrogation
signal received via a first antenna, the first resonant circuit provides an
output
that powers the second resonant circuit, and the second antenna emits a
response signal comprised of respective output signals received from the first
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resonant circuit and the second resonant circuit, according to at least one
illustrated implementation.
Figure 4 is a schematic diagram of a pouch that is physically
coupled to a piece of absorbent material, in which the pouch includes an
interior
cavity that may receive at least one wirelessly detectable object, according
to at
least one illustrated implementation.
Figure 5 is a schematic diagram of a wirelessly detectable object
that is physically coupled to a piece of absorbent material, according to at
least
one illustrated implementation.
Figure 6 is a block diagram of a processor-enabled device,
according to at least one illustrated implementation.
Figure 7 is a logic flow diagram of a method of operation of a
wirelessly detectable object that receives an interrogation signal and emits a
variable-frequency response signal, according to at least one illustrated
implementation.
DETAILED DESCRIPTION
In the following description, certain specific details are set forth in
order to provide a thorough understanding of various disclosed embodiments.
However, one skilled in the relevant art will recognize that embodiments may
be
practiced without one or more of these specific details, or with other
methods,
components, materials, etc. In other instances, well-known structures
associated with transmitters, receivers, or transceivers and/or medical
equipment and medical facilities have not been shown or described in detail to
avoid unnecessarily obscuring descriptions of the embodiments.
Unless the context requires otherwise, throughout the
specification and claims which follow, the word "comprise" and variations
thereof, such as "comprises" and "comprising," are to be construed in an open,
inclusive sense, that is as "including, but not limited to."
Reference throughout this specification to "one embodiment" or
"an embodiment" means that a particular feature, structure or characteristic
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described in connection with the embodiment is included in at least one
embodiment. Thus, the appearances of the phrases "in one embodiment" or "in
an embodiment" in various places throughout this specification are not
necessarily all referring to the same embodiment. Furthermore, the particular
features, structures, or characteristics may be combined in any suitable
manner
in one or more embodiments.
As used in this specification and the appended claims, the
singular forms "a," "an," and "the" include plural referents unless the
content
clearly dictates otherwise. It should also be noted that the term "or" is
generally
employed in its sense including "and/or" unless the content clearly dictates
otherwise.
The headings and Abstract of the Disclosure provided herein are
for convenience only and do not interpret the scope or meaning of the
embodiments.
Figure 1 shows a system 100 that includes a transceiver 102 and
a wirelessly detectable object 104, in which the transceiver 102 may emit an
interrogation signal 106 that is received by the wirelessly detectable object
104,
and the wirelessly detectable object 104 may return in response a wireless
response signal 108, according to at least one illustrated implementation. In
some implementations, the transceiver 102 may receive the wireless response
signal 108 returned by the wirelessly detectable object 104 and may perform
additional processing on the wireless response signal 108. In some
implementations, the transceiver 102 may be comprised of a wand 110 that
emits interrogation signals 106 of one or more frequencies that are used to
detect wirelessly detectable objects 104 that have been attached or physically
coupled to items used in a medical and/or surgical setting. Such items may
include, for example, gauze, bandages, medical sponges, medical equipment,
or other items that may be used in medical and/or surgical procedures. In such
situations, the wand 110 may be used to prevent these items from being lost,
or
from being left in dangerous or undesirable locations by detecting the
respective wirelessly detectable objects 104 attached to such items. In some
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situations, for example, the wand 110 may be passed over a patient after an
operation or other medical procedure to detect any wirelessly detectable
objects 104 that are attached to items, such as surgical gauze, bandages, or
sponges, used in the medical and/or surgical procedure. Such items, once
detected, may be removed from the patient.
The wirelessly detectable object 104 may include an antenna 112
and a passive variable-frequency transponder circuit 114. The antenna 112
may be used to transmit and/or receive wireless signals, and may be
communicatively coupled to the passive variable-frequency transponder circuit
114. In some implementations, the interrogation signal 106 emitted by the
transceiver 102 may be received by the passive variable-frequency transponder
circuit 114 via the antenna 112. The passive variable-frequency transponder
circuit 114 may be comprised of one or more circuits such as, for example,
tank
circuits, LC circuits, RLC circuits, or other types of circuits that may be
powered
by the interrogation signal 106. As such, the interrogation signal may cause a
voltage potential to be generated across the passive variable-frequency
transponder circuit 114 when the interrogation signal 106 is received by the
passive variable-frequency transponder circuit 114. When the interrogation
signal 106 is no longer received by the passive variable-frequency transponder
circuit 114, e.g., when the interrogation signal 106 has been turned off or
the
passive variable-frequency transponder circuit 114 has moved away from the
source of the interrogation signal 106, the voltage potential across the
passive
variable-frequency transponder circuit 114 may begin to decay at a defined
rate.
The passive variable-frequency transponder circuit 114 may
generate a response signal upon receiving the interrogation signal 106. In
some implementations, the response signal generated by the passive variable-
frequency transponder circuit 114 may be the wireless response signal 108 that
has a frequency that varies with respect to time. In some implementations, the
frequency of the wireless response signal 108 may be varied, for example, by
changing the value(s) of one or more components (e.g., inductors, capacitors,
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resistors) in the passive variable-frequency transponder circuit 114. In some
implementations, the values of such components may be changed using, for
example, a control voltage. As such, a change in the control voltage may
result
in the frequency of the wireless response signal 108 to increase and/or
decrease based upon the corresponding change in value of the one or more
components in the passive variable-frequency transponder circuit 114. In some
implementations, the control voltage used to change the frequency of the
wireless response signal 108 may be related to the voltage generated across
the passive variable-frequency transponder circuit 114 by the interrogation
signal 106. Because the voltage across the passive variable-frequency
transponder circuit 114 changes (e.g., decays) when the interrogation signal
106 is no longer received, the change in this voltage may be used to vary the
frequency of the wireless response signal 108. The'passive variable-frequency
transponder circuit 114 may return the wireless response signal 108 via the
antenna 112.
In some implementations, the frequency of the wireless response
signal 108 may be varied in other ways. For example, in some
implementations, a switch may be used to selectively couple and decouple
components (e.g., inductors, capacitors, resistors) within the passive
variable-
frequency transponder circuit 114. Such selective coupling and de-coupling of
components may be used to vary the frequency of the wireless response signal
108 generated by the passive variable-frequency transponder circuit 114.
In some implementations, the variations or changes in the
frequency of response signal returned by the wireless response signal 108 may
be used to provide a signature for the wirelessly detectable object 104. In
some instances, as discussed above for example, the voltage across the
passive variable-frequency transponder circuit 114 may decay at a well-defined
rate when the interrogation signal 106 is no longer received. As such, the
defined decay in the voltage across the passive variable-frequency transponder
circuit 114 may result in the corresponding change in the frequency of the
wireless response signal 108 to also be well-defined, such that the change in
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frequency of the wireless response signal 108 may be used to produce a
characteristic signature in the wireless response signal 108. Such a
characteristic signal may be repeated during each interrogation cycle during
which the passive variable-frequency transponder circuit 114 is powered by the
interrogation signal 106. In some instances, switches may be used to
selectively couple and decouple components within the passive variable-
frequency transponder circuit 114. Such selectively coupling and decoupling
may be used to generate a characteristic signature for the wireless response
signal 108. In some implementations, the transceiver 102 may detect the
characteristic signature within the wireless response signal 108. As such, the
transceiver 102 may associate the wireless response signal 108 with the
wirelessly detectable object 104 and/or may perform additional processing
based upon the detected characteristic signature.
In some implementations, the wireless response signal 108 may
be used to determine a distance to the wirelessly detectable object 104. For
example, in some implementations, the transceiver 102 may detect the wireless
response signal 108 emitted by the antenna 112, and use information regarding
the wireless response signal 108 to determine a distance 116 between the
transceiver 102 and the antenna 112 portion of the wirelessly detectable
object
104. Such a determination may be based upon the strength, e.g., power
density, of the wireless response signal 108 that is emitted by the antenna
112
when the passive variable-frequency transponder circuit 114 is fully powered.
Such a value for the power density may be defined based upon the structure
and design of the passive variable-frequency transponder circuit 114.
Accordingly, the value for the power density of the wireless response signal
108
emitted by the antenna 112 may have a known value. When the wireless
response signal 108 propagates outward from the antenna 112, the power
density of the wireless response signal 108 decreases at a known rate.
Accordingly, in some implementations, the distance 116 may be determined
based upon the known power density of the wireless response signal 108 as
emitted by the antenna 112, the known rate at which the power density
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decreases across distances, and the measured value of the power density of
the wireless response signal at the transceiver 102.
As an example, in some implementations, the value of the power
density of the wireless response signal 108 at any location may be inversely
proportional to the square of the distance between that location and the
antenna 112. Accordingly, the transceiver 102 may determine the distance 116
between the antenna 112 and the transceiver 102 by comparing the power
density of the wireless response signal 108 received at the transceiver 102
with
the known power density of the wireless response signal 108 as emitted by the
antenna 112. In some implementations, the distance 116 may be determined
according to the following:
d = Pantenna
Eq. 1
Ptransceiver
d = Distance 116 between the transceiver 102 and the antenna 112
Pantenna = Power density of wireless response signal 108 at antenna 112
(known)
Pantenna = Power density of wireless response signal 108 received at
transceiver 102 (measured)
In some implementations, a distance range between the antenna
112 and the transceiver 102 may be determined. Such a distance range may
be based, for example, upon one or more factors, such as tolerance levels for
detecting and measuring the power density of the wireless response signal 108
at the transceiver 102, and/or the precision of the power density of the
wireless
response signal 108 as emitted by the antenna 112. In some implementations,
the distance range may be based upon a percentage of the distance 116 as
determined based upon measurements at the transceiver 102. Such
determinations of the distance and/or distance range may be provided by a
processor-enabled component, such as the transceiver 102 and/or any other
processor-enabled component that may be communicatively coupled to the
transceiver 102.
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Figure 2A shows a wirelessly detectable object 104 that includes
an antenna 112 and a passive variable-frequency transponder circuit 114 that
includes an inductor 200 and a varactor diode 202, according to at least one
illustrated implementation. In such an implementation, the antenna 112 may
receive an interrogation signal 106, such as one that may be transmitted by
the
transceiver 102. Such an interrogation signal 106 may be transmitted via the
antenna 112 to the passive variable-frequency transponder circuit 114, which
may include the inductor 200 and the varactor diode 202. The varactor diode
202 may function as a variable capacitor in which the capacitance of the
varactor diode 202 varies as a function of a control voltage 204. In some
implementations, for example, the capacitance of the varactor diode 202 may
be based upon the voltage potential across the varactor diode 202, such that
this voltage potential controls the value of the capacitance of the varactor
diode
202.
In some implementations, the inductor 200 and the varactor diode
202 may form a resonant circuit that is energized when receiving
electromagnetic waves of a defined frequency and/or a defined frequency
range. In such implementations, the values of the inductor 200 and/or the
varactor diode 202 may be chosen such that the passive variable-frequency
transponder circuit 114 is energized by the frequency of the interrogation
signal
106. Once energized, the passive variable-frequency transponder circuit 114
may generate a response voltage across the passive variable-frequency
transponder circuit 114. The response voltage may be used to generate a
response signal with a resonant frequency in which the resonant frequency may
be based upon the respective values of the components that comprise the
passive variable-frequency transponder circuit 114, such as for example, the
value of the inductance for the inductor 200 and/or the value of the
capacitance
of the varactor diode 202.
In some implementations, the response voltage across the
passive variable-frequency transponder circuit 114 may provide a control
voltage 204 that may be used to control the values of one or more components
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in the passive variable-frequency transponder circuit 114. For example, in
some implementations, the control voltage 204 may be used to control the
capacitance of the varactor diode 202. In such implementations, the response
voltage in the passive variable-frequency transponder circuit 114 may soon
reach a maximum value when the interrogation signal 106 is received, and
maintain such a maximum value as long as the antenna 112 receives the
interrogation signal 106. As such, the capacitance of the varactor diode 202
may also reach a steady value during this period such that the passive
variable-
frequency transponder circuit 114 generates a wireless response signal 108
with a steady frequency while the passive variable-frequency transponder
circuit 114 is powered by the interrogation signal. When the interrogation
signal
106 is no longer present, the control voltage 204 may decay at a defined rate
in
which the rate of decay may be based, for example, on the value of the
varactor
diode 202 and/or the value of the inductor 200. As a result, the capacitance
of
the varactor diode 202 may correspondingly change as the control voltage 204
decays.
The change in the capacitance of the varactor diode 202 may
result in the frequency of the wireless response signal 108 also changing. In
some instances, for example, the value of the capacitance of the varactor
diode
202 may be inversely varied with respect to the control voltage 204 such that
the capacitance of the varactor diode 202 increases as the control voltage 204
decays. The resonant frequency of the passive variable-frequency transponder
circuit 114 may be inversely proportional to the value of the capacitance of
the
varactor diode 202 such that the resonant frequency of the wireless response
signal 108 generated by the passive variable-frequency transponder circuit 114
decreases as the capacitance of the varactor diode 202 increases.
In some implementations, the inductor 200 may be comprised of
= one or more rods 206. Such rods 206 may be used to inductively couple the
inductor 200 to, for example, the transceiver 102. As such, this electrical
coupling of the rods 206 with the transceiver 102 may be used to energize the
passive variable-frequency transponder circuit 114. In such an implementation,
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the one or more rods 206 may be oriented in different directions to improve
the
overall amount of energy captured by the set of rods 206. In some
implementations, for example, the inductor 200 may be comprised of two or
three rods 206 in which each rod 206 is at a 900 angle with respect to each of
the other rods 206. In such an implementation, the set of rods 206 may be
contained within a spherical housing to protect the set of rods 206. The rods
206 may be comprised of any type of material that may be used to inductively
couple to another component. For example, in some implementations, one or
more of the rods 206 may be comprised of a ferrite rod. In some instance, the
ferrite rode may have a conductive coil wrapped about an exterior surface
thereof to form an inductor.
Figure 2B shows a wirelessly detectable object 104 that includes
an antenna 112 and a variable-frequency transponder circuit 114 that includes
a first capacitor 208 that may be selectively, electrically coupled to the
other
components in the wirelessly detectable object 104, according to at least one
illustrated implementation. In such an implementation, the other components in
the passive variable-frequency transponder circuit 114 may include a second
capacitor 210 and an inductor 212. When the first capacitor 208 is
selectively,
decoupled from the other components in the passive variable-frequency
transponder circuit 114, the other components (e.g., the second capacitor 210
and the inductor) may form a first resonant circuit that generates a response
signal having a first frequency and/or frequency range. When the first
capacitor
208 is selectively coupled to the other components in the passive variable-
frequency transponder circuit 114, the first capacitor 208, the second
capacitor
210, and the inductor 212 may form a second resonant circuit that generates a
response signal having a second frequency and/or frequency range. In some
implementations, the second frequency may be lower than the first frequency.
In some implementations, the first capacitor 208 may be
selectively coupled and decoupled to the other components in the passive
variable-frequency transponder circuit 114 using a switch 214. In some
implementations, the switch 214 may be comprised of one or more transistors
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216 that may be controlled by a control voltage 218. Accordingly, the control
voltage 218 may be selectively applied to the transistor 216 to maintain the
transistor 216 in one of a CLOSED state and an OPEN state. When the
transistor 216 is in an OPEN state, the first capacitor 208 is electrically
decoupled to the remaining components in the passive variable-frequency
transponder circuit 114, resulting in the first resonant circuit having a
first
resonant frequency. When the transistor 216 is in the CLOSED state, the first
capacitor 208 is electrically coupled to the remaining components in the
passive
variable-frequency transponder circuit 114. In some implementations, the
switch 214 may be selectively transitioned between the OPEN state and the
CLOSED state in a defined pattern. As such, the defined pattern of switching
between the first frequency and the second frequency to generate a response
signal that has a characteristic signature. Such a characteristic signature
may
be detected by the transceiver 102.
In some implementations, the inductor 200 may be comprised of
one or more rods 206. Such rods 206 may be used to inductively couple the
inductor 200 to, for example, the transceiver 102. As such, this electrical
coupling of the rods 206 with the transceiver 102 may be used to energize the
passive variable-frequency transponder circuit 114. In such an implementation,
the one or more rods 206 may be oriented in different directions to improve
the
overall amount of energy captured by the set of rods 206. In some
implementations, for example, the inductor 200 may be comprised of two or
three rods 206 in which each rod 206 is at a 90 angle with respect to each of
the other rods 206. In such an implementation, the set of rods 206 may be
contained within a spherical housing to protect the set of rods 206. The rods
206 may be comprised of any type of material that may be used to inductively
couple to another component. For example, in some implementations, one or
more of the rods 206 may be comprised of ferrite.
Figure 3A shows a wirelessly detectable object 104 that includes
a first resonant circuit 300 that is electrically coupled to a second resonant
circuit 302, in which the first resonant circuit 300 is powered by the
interrogation
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signal 106 received via a first antenna 304, the first resonant circuit 300
provides an output that powers the second resonant circuit 302, and the second
antenna 306 emits a wireless response signal 108 comprised of an output
signal received from the second resonant circuit 302, according to at least
one
illustrated implementation. In such an implementation, the passive variable-
frequency transponder circuit 114 may include a switch 308 that may be used
to selectively couple the first resonant circuit 300 to the second antenna
306.
As shown in Figure 3A, the switch 308 may be in an open position such that the
first resonant circuit 300 is decoupled from the second antenna 306. In some
implementations, the electrical coupling between the first resonant circuit
300
and the second resonant circuit 302 may include an inductive coupled via, for
example, one or more pairs of windings such that power generated in one
resonant circuit may be transferred to the other resonant circuit.
In such an implementation, the first resonant circuit 300 may
receive the interrogation signal 106 via the first antenna 304. The
interrogation
signal 106 may power the first resonant circuit 300 when the interrogation
signal 106 is received via the first antenna 304. The first resonant circuit
300
may generate a first response signal having a first frequency when powered by
the interrogation signal 106. In addition, powering the first resonant circuit
300
may result in the second resonant circuit 302 being powered via, for example,
the electrical coupling. When the second resonant circuit 302 is powered, the
second resonant circuit 302 may generate a second response signal having a
second frequency. The second response signal may be emitted by the second
antenna 306 as the wireless response signal 108 from the passive variable-
frequency transponder circuit 114. In some implementations, the frequency of
the second response signal, and the wireless response signal 108, may be
varied as noted above.
As shown in Figure 3A, the wireless response signal 108 may be
emitted by the second antenna 306 simultaneously with the interrogation signal
106 being received at the first antenna 304. As such, the first resonant
circuit
300 may be continuously powered by the interrogation signal 106 even while
18
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the wireless response signal 108 is emitted by the second antenna 306. Such
an implementation may not need to operate with separate discrete time periods
to receive the interrogation signal 106 and to emit the wireless response
signal
108. Such an implementation may advantageously reduce the amount of time
needed to detect the wirelessly detectable object 104.
Figure 3B shows a wirelessly detectable object 104 that includes
the first resonant circuit 300 that is electrically coupled to a second
resonant
circuit 302, in which the first resonant circuit 300 is powered by the
interrogation
signal 106 received via the first antenna 304, the first resonant circuit 300
powers the second resonant circuit 302, and the second antenna 306 emits a
wireless response signal 108 comprised of respective output signals received
from the first resonant circuit 300 and the second resonant circuit 302,
according to at least one illustrated implementation. In such an
implementation,
the switch 308 may be closed in order to selectively couple the first resonant
circuit 300 to the second antenna 306. In some implementations, the electrical
coupling between the first resonant circuit 300 and the second resonant
circuit
302 may include an inductive coupled via, for example, one or more pairs of
windings such that power generated in one resonant circuit may be transferred
to the other resonant circuit.
In such an implementation, the first resonant circuit 300 may
receive the interrogation signal 106 via the first antenna 304. The
interrogation
signal 106 may power the first resonant circuit 300 when the interrogation
signal 106 is received via the first antenna 304. The first resonant circuit
300
may generate a first response signal having a first frequency when powered by
the interrogation signal 106. In addition, powering the first resonant circuit
300
may result in the second resonant circuit 302 being powered via, for example,
the electrical coupling between the first resonant circuit 300 and the second
resonant circuit 302. When the second resonant circuit 302 is powered, the
second resonant circuit 302 may generate a second response signal having a
second frequency. The second antenna 306 may emit a wireless response
signal 108 that is comprised of both the first response signal from the first
19
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resonant circuit 300 and the second response signal from the second resonant
circuit 302. In such an implementation, the combination of the first resonant
circuit 300 and the second resonant circuit 302 may cause the wireless
response signal 108 to have a beat. Such a beat may have a distinctive
frequency (e.g., a beat frequency) that may be related to the difference
between the frequency of the first response signal and the frequency of the
second response signal. In some implementations, the beat frequency may
advantageously be used to detect the wireless response signal 108. In some
implementations, the beat frequency may be used to provide a characteristic
signal for the passive variable-frequency transponder circuit 114.
As shown in Figure 3B, the wireless response signal 108 may be
emitted by the second antenna 306 simultaneously with the interrogation signal
106 being received at the first antenna 304. As such, the first resonant
circuit
300 may be continuously powered by the interrogation signal 106 even while
the wireless response signal 108 is emitted by the second antenna 306. Such
an implementation may not need to operate with separate discrete time periods
to receive the interrogation signal 106 and to emit the wireless response
signal
108. Such an implementation may advantageously reduce the amount of time
needed to detect the wirelessly detectable object 104.
Figure 4 shows a pouch 400 that is physically coupled to a piece
of absorbent material 402, in which the pouch 400 includes an interior cavity
404 that may receive at least one wirelessly detectable object 104, according
to
at least one illustrated implementation. The wirelessly detectable object 104
may be comprised of the antenna 112 and the passive variable-frequency
transponder circuit 114. The pouch 400 may take the form of a hollowed
rectangle, circle, oval, or other shape to form the interior cavity 401 within
a
perimeter of the hollowed area. In some implementations, the wirelessly
detectable object 104 is freely movable within the interior cavity 401 of the
pouch 400. Such may advantageously allow folding, stretching, compression,
twisting, or other physical manipulation of the piece of absorbent material
402
without causing damage to the wirelessly detectable object 104. For example,
CA 3056101 2019-09-20
the wirelessly detectable object 104 may freely move within the pouch 400 to
an advantageous position experiencing reduced forces. Likewise, the free-
floating wirelessly detectable object 104 does not inhibit folding,
stretching,
compression, twisting, or other physical manipulation of the piece of
absorbent
material 402, which may be necessary for the surgical procedure.
In some implementations, the pouch 400 includes at least a first
flexible layer that forms the interior cavity 404. For example, the first
flexible
layer can be physically coupled to a surface of the absorbent material 402 to
form the interior cavity 404 there between. As another example, the pouch 400
may include a second flexible layer opposite the first flexible layer and
physically coupled to the first flexible layer to form the interior cavity 404
there
between.
The pouch 400 may include an adhesive layer that may be
physically coupled to one or both of the first flexible layer and the second
flexible layer. Furthermore, in some implementations, the adhesive layer
physically couples the pouch 400 to a piece of absorbent material 402. The
adhesive layer may retain structural and adhesive integrity at least at
temperatures equal to 121, 130, 132, 136, and/or 150 degrees Centigrade or
higher. For example, the adhesive layer may not melt or otherwise liquefy and
may retain adhesion to the first flexible layer, second flexible layer and/or
the
piece of the absorbent material at temperatures less than or equal to 121,
130,
132, 136, and/or 150 degrees Centigrade or higher.
In some implementations, a radio frequency (RF) weld physically
couples the first flexible layer to one or both of the second flexible layer
and the
adhesive layer. Alternatively or additionally to RF weld, adhesives,
stitching,
clamping, fasteners, or other securing means can physically couple the first
flexible layer to the absorbent material 402 or the second flexible layer.
The first and/or second flexible layers and may be fabric
laminates or other materials. For example, the first and/or second flexible
layers and may be one or more of thermoplastic polyurethane (TPU) and nylon
fabric; polyvinyl chloride (PVC) impregnated fabric; layer(s) of PVC, TPU,
PET,
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PETG, LDPE, EVA, open celled polyurethanes, or nylon; other fabrics (e.g.,
cotton, polyester, leather, vinyl, polyethylene, and blended fabrics); other
plastics; or combinations thereof. The flexible layers and are typically
relatively
thin and may be absorbent or non-absorbent. In some implementations, the
flexible layers are of material suitable to prevent entry of fluids into the
interior
cavity of the pouch 400 (e.g., due to a water-proof or water-resistant
coating).
Thus, the first and/or second flexible layers and may be soft, pliable, and
resistant to ripping or tearing. In one particular example, the first flexible
layer
includes a first layer of TPU and a first layer of nylon fabric. The second
flexible
layer includes a second layer of TPU and a second layer of nylon fabric. The
TPU layers may be positioned to advantageously allow the first and second
layers of TPU to more completely melt together or otherwise physically couple
to each other when the RF weld is generated. However, in other
implementations, the first and second layers of nylon fabric may be located
interior, relative to the first and second layers of TPU or may be embedded
within the first and second layers of TPU.
In some implementations, the adhesive layer may be a hot melt
adhesive layer. In such implementations, the pouch 400 may be constructed at
least in part by causing the temperature of at least a portion the hot melt
adhesive layer to exceed a melting point temperature associated with the hot
melt adhesive layer, thereby causing such portion to at least in part melt.
For
example, such may be performed using an RF welding machine, planar heat
pressing machine, hot-air welding machine, or laminator. Alternatively, the
pouch 400 may be baked (e.g., in a chamber) or exposed to various other
techniques for applying heat and/or pressure at desired locations. Generally,
the melting point temperature will be at least greater than 130 degrees
Centigrade. Thus, the adhesive layer may be a pre-formed solid layer that is
positioned or laid adjacent to the first and/or the second flexible layers and
then
caused to at least in part melt and then re-solidify, thereby engaging the
first
and/or the second flexible layers and resulting in physical coupling
therewith.
For example, in some implementations, the second layer may be a porous
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fabric such that the adhesive layer melts through the pores of the fabric to
engage the first flexible layer to result in physical coupling of the first
flexible
layer to the second flexible layer.
The pouch 400 is physically coupleable to the absorbent material
402. For example, the pouch 400 includes an adhesive layer positioned
opposite the second flexible layer from the first flexible layer. The adhesive
layer may be a hot melt adhesive layer that is meltable to physically couple
the
pouch 400 to a piece of absorbent material but that has a melting point
temperature greater than one or more sterilization temperatures at which
common sterilization techniques are performed, thereby permitting the pouch
400 to remain physically coupled to the piece of absorbent material through
one
or multiple sterilization cycles.
Figure 5 shows a wirelessly detectable object 104 that is
physically coupled to a piece of absorbent material 402, according to at least
one illustrated implementation. Adhesives, stitching, clamping, fasteners,
heat
sealing, RF welding, or other securing means physically couple the wirelessly
detectable object 104 to the piece of absorbent material 402.
The wirelessly detectable object 104 may include an adhesive
layer that physically couples the wirelessly detectable object 104 to the
piece of
absorbent material 402 or other surgical object. The adhesive layer may retain
structural and adhesive integrity at least at temperatures equal to 121
degrees
Centigrade, 130 degrees Centigrade, 132 degrees Centigrade, 136 degrees
Centigrade, and/or 150 degrees Centigrade, or higher. Thus, the adhesive
layer may not melt or otherwise liquefy and may retain adhesion to the
remainder of the wirelessly detectable object 104 at temperatures less than or
equal to 121, 130, 132, 136, and/or 150 degrees Centigrade or higher. In some
implementations, the adhesive layer may retain the structural and adhesive
integrity at least at temperatures equal to 150 degrees Centigrade or higher.
As an example, the adhesive layer may be a hot melt adhesive
layer positioned between the surgical object and the remainder of the
wirelessly
detectable object 104. In such implementations, the wirelessly detectable
23
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object 104 may be physically coupled to the surgical object by causing the
temperature of at least a portion the hot melt adhesive layer to exceed a
melting point temperature associated with the hot melt adhesive layer, thereby
causing such portion to at least in part melt. For example, such may be
performed using an RF welding machine, planar heat pressing machine, hot-air
welding machine, or laminator. Alternatively, the wirelessly detectable object
104 and the surgical object may be baked (e.g., in a chamber) or exposed to
various other techniques for applying heat and/or pressure at desired
locations.
Generally, the melting point temperature will be at least greater than 121
degrees Centigrade, but may be other temperatures in various
implementations.
In contrast to an epoxy that is applied in liquid form and then
cured, the adhesive layer of the wirelessly detectable object 104 may be a pre-
formed solid layer that is positioned or laid between the remainder of the
wirelessly detectable object 104 and the surgical object. The adhesive layer
may then be caused to at least in part melt and then re-solidify, thereby
engaging the remainder of the wirelessly detectable object 104 and the
surgical
object and resulting in physical coupling therewith.
In some implementations, the hot melt adhesive layer is a high
temperature hot melt adhesive layer (i.e., a hot melt adhesive layer that has
a
relatively high melting point temperature). For example, the hot melt adhesive
layer may have a melting point temperature of greater than 121 degrees
Centigrade, greater than 130 degrees Centigrade, greater than 132 degrees
Centigrade, or greater than 136 degrees Centigrade. As another example, the
hot melt adhesive layer may have a melting point temperature of about 150
degrees Centigrade or higher. The hot melt adhesive layer may have a melting
point temperature greater than a sterilization temperature associated with one
or more sterilization procedures. For example, the hot melt adhesive layer may
have a melting point temperature greater than a steam temperature at which a
volume of steam is maintained during one or more steam-based sterilization
procedures. For example, two common steam-based sterilization techniques
24
CA 3056101 2019-09-20
use a volume of steam respectively maintained at 121 degrees Centigrade (250
degrees Fahrenheit) and 132 degrees Centigrade (270 degrees Fahrenheit).
The hot melt adhesive layer may have a melting point temperature greater than
one or both of such temperatures.
In some implementations, the adhesive layer is biocompatible,
permitting use of the wirelessly detectable object 104 in vivo. In some
implementations, the adhesive layer is an adhesive web film. In some
implementations, the adhesive layer is a thermal lamination film. The adhesive
layer may be a meltable plastic layer, such as, for example, a thermoplastic
layer.
In some implementations, the adhesive layer may be a
thermosetting plastic layer that has an initial cure temperature at which the
thermosetting plastic layer cures. For example, the initial cure temperature
may
be less than 130 degrees Centigrade. Subsequent to curing, the thermosetting
plastic layer may retain structural and adhesive integrity at least at
temperatures less than or equal to 121, 130, 132, 136, and/or 150 degrees
Centigrade or higher.
In some implementations, the adhesive layer may be a heat-
activated adhesive layer. Alternatively or additionally, the adhesive layer
may
be a pressure-activated adhesive layer or a pressure-sensitive adhesive layer.
Alternatively or additionally, the adhesive layer may be a water-activated
adhesive layer. The adhesive layer may include at least one of thermoplastic
polyurethane, silicone, polyamide, polyethersulfone, polyethylene,
polypropylene, and ethylene vinyl acetate.
Figure 6 shows a processor-enable device 600, according to at
least one illustrated implementation. The control system may be used to
implement, for example, the transceiver 102, such as the wand 110. The
processor-enabled device 600 may take the form of any current or future
developed computing system capable of executing one or more instruction sets.
The processor-enabled device 600 includes a processing unit 602, a system
memory 604, and a system bus 606 that communicably couples various system
CA 3056101 2019-09-20
components including the system memory 604 to the processing unit 602. The
processor-enabled device 600 will at times be referred to in the singular
herein,
but this is not intended to limit the embodiments to a single system, since in
certain embodiments, there will be more than one system or other networked
computing device involved. Non-limiting examples of commercially available
systems include, but are not limited to, an Atom, Pentium, or 80x86
architecture
microprocessor as offered by Intel Corporation, a Snapdragon processor as
offered by Qualcomm, Inc., a PowerPC microprocessor as offered by IBM, a
Sparc microprocessor as offered by Sun Microsystems, Inc., a PA-RISC series
microprocessor as offered by Hewlett-Packard Company, an A6 or A8 series
processor as offered by Apple Inc., or a 68xxx series microprocessor as
offered
by Motorola Corporation.
The processing unit 602 may be any logic processing unit, such
as one or more central processing units (CPUs), microprocessors, digital
signal
processors (DSPs), application-specific integrated circuits (ASICs), field
programmable gate arrays (FPGAs), programmable logic controllers (PLCs),
etc. Unless described otherwise, the construction and operation of the various
blocks shown in Figure 6 are of conventional design. As a result, such blocks
need not be described in further detail herein, as they will be understood by
those skilled in the relevant art.
The system bus 606 can employ any known bus structures or
architectures, including a memory bus with memory controller, a peripheral
bus,
and a local bus. The system memory 604 includes read-only memory ("ROM")
608 and random access memory ("RAM") 610. A basic input/output system
.. ("BIOS") 612, which can form part of the ROM 608, contains basic routines
that
help transfer information between elements within the processor-enabled
device 600, such as during start-up. Some embodiments may employ separate
buses for data, instructions and power.
The processor-enabled device 600 also includes one or more
internal nontransitory storage systems 614. Such internal nontransitory
storage
systems 614 may include, but are not limited to, any current or future
developed
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persistent storage device 616. Such persistent storage devices 616 may
include, without limitation, magnetic storage devices such as hard disc
drives,
electromagnetic storage devices such as memristors, molecular storage
devices, quantum storage devices, electrostatic storage devices such as solid
state drives, and the like.
The processor-enabled device 600 may also include one or more
optional removable nontransitory storage systems 618. Such removable
nontransitory storage systems 618 may include, but are not limited to, any
current or future developed removable persistent storage device 620. Such
removable persistent storage devices 620 may include, without limitation,
magnetic storage devices, electromagnetic storage devices such as
memristors, molecular storage devices, quantum storage devices, and
electrostatic storage devices such as secure digital ("SD") drives, USB
drives,
memory sticks, or the like.
The one or more internal nontransitory storage systems 614 and
the one or more optional removable nontransitory storage systems 618
communicate with the processing unit 602 via the system bus 606. The one or
more internal nontransitory storage systems 614 and the one or more optional
removable nontransitory storage systems 618 may include interfaces or device
controllers (not shown) communicably coupled between nontransitory storage
system and the system bus 606, as is known by those skilled in the relevant
art.
The nontransitory storage systems 614, 618, and their associated storage
devices 616, 620 provide nonvolatile storage of computer-readable
instructions,
data structures, program modules and other data for the processor-enabled
device 600. Those skilled in the relevant art will appreciate that other types
of
storage devices may be employed to store digital data accessible by a
computer, such as magnetic cassettes, flash memory cards, RAMs, ROMs,
smart cards, etc.
Program modules can be stored in the system memory 604, such
as an operating system 622, one or more application programs 624, other
programs or modules 626, drivers 628 and program data 630.
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The application programs 624 may include, for example, one or
more machine executable instruction sets (i.e., detection module 624a) capable
of detecting one or more wireless response signal 108 transmitted by
wirelessly
detectable objects 104. The application programs 624 may include, for
example, one or more machine executable instruction sets (i.e., distance
module 624b) capable of detecting the distance between the transceiver 102
and a wirelessly detectable object 104.
In some embodiments, the processor-enabled device 600
operates in an environment using one or more of the network interfaces 632 to
optionally communicably couple to one or more remote computers, servers,
display devices, and/or other devices via one or more communications
channels. These logical connections may facilitate any known method of
permitting computers to communicate, such as through one or more LANs
and/or WANs. Such networking environments are well known in wired and
wireless enterprise-wide computer networks, intranets, extranets, and the
Internet.
Figure 7 is a logic flow diagram of a method of operation of a
wirelessly detectable object that receives an interrogation signal and emits a
variable-frequency response signal, according to at least one illustrated
implementation. The method 700 can, for example, be executed by one or
more wirelessly detectable circuits 102 and may start at 702.
At 704, a wirelessly detectable object 104 may receive an
interrogation signal 704 via, for example, one or more antennas (e.g., antenna
112). Such an interrogation signal 704 may be generated by and transmitted
from a transceiver 102, such as the wand 110. Such an interrogation signal
106 may be comprised of one or more frequencies, and such frequencies may
be used to detect wirelessly detectable objects 104 that have been attached or
physically coupled to items, such as items that may be used in a medical
and/or
surgical setting. These items may include, for example, gauze, bandages,
medical sponges, medical equipment, or other items that may be used in
medical and/or surgical procedures. In such situations, the interrogation
signals
28
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106 emitted by the transceiver 102 may be used to detect the respective
wirelessly detectable objects 104 attached to such items so as to prevent
these
items from being lost, or from being left in dangerous or undesirable
locations.
At 706, a wirelessly detectable object 104 may be powered by the
received interrogation signal 704. In some implementations, the wirelessly
detectable object 104 may include a passive variable-frequency transponder
circuit 114 that may be comprised of one or more circuits such as, for
example,
tank circuits, LC circuits, RLC circuits, or other types of circuits that may
be
powered by the interrogation signal 106. As such, the interrogation signal may
cause a voltage potential to be generated across the passive variable-
frequency transponder circuit 114 when the interrogation signal 106 is
received
by the passive variable-frequency transponder circuit 114. When the
interrogation signal 106 is no longer received by the passive variable-
frequency
transponder circuit 114, e.g., when the interrogation signal 106 has been
turned
off or the passive variable-frequency transponder circuit 114 has moved away
from the source of the interrogation signal 106, the voltage potential across
the
passive variable-frequency transponder circuit 114 may begin to decay at a
defined rate.
At 708, a wirelessly detectable object 104 may return a wireless
response signal 108 that has a variable frequency via an antenna (e.g., the
antenna 112, and/or the second antenna 306). In some implementations, the
wireless response signal 1.08 may be generated by the passive variable-
frequency transponder circuit 114, and the wireless response signal 108 may
be emitted by the antenna. In some implementations, the frequency of the
wireless response signal 108 may be varied, for example, by changing the
value(s) of one or more components (e.g., inductors, capacitors, resistors) in
the passive variable-frequency transponder circuit 114 using, for example, a
control voltage, as discussed above. As such, a change in the control voltage
may result in the frequency of the wireless response signal 108 to increase
and/or decrease based upon the corresponding change in value of the one or
more components in the passive variable-frequency transponder circuit 114. In
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CA 3056101 2019-09-20
some implementations, the frequency of the wireless response signal 108 may
be varied in other ways. For example, in some implementations, a switch may
be used to selectively couple and decouple components (e.g., inductors,
capacitors, resistors) within the passive variable-frequency transponder
circuit
114. Such selective coupling and de-coupling of components may be used to
vary the frequency of the wireless response signal 108 generated by the
passive variable-frequency transponder circuit 114.
At 710, the method 700 terminates, for example until invoked
again. Alternatively, the method 700 may repeat continuously or repeatedly, or
may execute as multiple instances of a multi-threaded process.
The foregoing detailed description has set forth various
embodiments of the devices and/or processes via the use of block diagrams,
schematics, and examples. Insofar as such block diagrams, schematics, and
examples contain one or more functions and/or operations, it will be
understood
.. by those skilled in the art that each function and/or operation within such
block
diagrams, flowcharts, or examples can be implemented, individually and/or
collectively, by a wide range of hardware, software, firmware, or virtually
any
combination thereof. In one embodiment, the present subject matter may be
implemented via Application Specific Integrated Circuits (ASICs). However,
those skilled in the art will recognize that the embodiments disclosed herein,
in
whole or in part, can be equivalently implemented in standard integrated
circuits, as one or more computer programs running on one or more computers
(e.g., as one or more programs running on one or more computer systems), as
one or more programs running on one or more controllers (e.g.,
microcontrollers) as one or more programs running on one or more processors
(e.g., microprocessors), as firmware, or as virtually any combination thereof,
and that designing the circuitry and/or writing the code for the software and
or
firmware would be well within the skill of one of ordinary skill in the art in
light of
this disclosure.
Various exemplary methods or processes are described. It is
noted that these exemplary methods or processes may include additional acts
CA 3056101 2019-09-20
I V
I =
and/or may omit some acts. In some implementations, the acts of the various
exemplary methods or processes may be performed in a different order and/or
some acts may be executed or performed concurrently.
In addition, those skilled in the art will appreciate that the
mechanisms of taught herein are capable of being distributed as a program
product in a variety of forms, and that an illustrative embodiment applies
equally
regardless of the particular type of physical signal bearing media used to
actually carry out the distribution. Examples of signal bearing media include,
but are not limited to, the following: recordable type media such as floppy
disks,
hard disk drives, CD ROMs, digital tape, and computer memory.
The various embodiments described above can be combined to
provide further embodiments. To the extent not inconsistent with the teachings
herein, all U.S. patents, U.S. patent application publications, U.S. patent
applications, foreign patents, foreign patent applications and non-patent
publications commonly owned with this patent application and referred to in
this
specification and/or listed in the Application Data Sheet including: U.S.
Patent
No. 6,026,818, issued February 22, 2000; U.S. Patent Publication No.
US 2004/0250819, published December 16, 2004; U.S. Patent 8,710,957,
issued April 29, 2014; U.S. Patent 7,898,420, issued March 1,2011; U.S.
Patent 7,696,877, issued April 13, 2010; U.S. Patent 8,358,212, issued January
22, 2013; U.S. Patent 8,111,162, issued February 7, 2012; U.S. Patent
8,354,931, issued January 15, 2013; U.S. Patent Publication No.
US 2010/0108079, published May 6, 2010; U.S. Patent Publication No.
US 2010/0109848, published May 6, 2010; U.S. Patent Publication No.
US 2011/0004276, published January 6, 2011; U.S. Patent Publication No.
US 2011/0181394, published July 28, 2011; U.S. Patent Publication No.
US 2013/0016021, published January 17, 2013; PCT Patent Publication No.
WO 2015/152975, published October 8, 2015; U.S. Provisional patent
application Serial No. 62/143,726 filed April 6, 2015; U.S. Provisional patent
application Serial No. 62/182,294 filed June 19, 2015; U.S. Provisional patent
application Serial No. 62/164,412 filed May 20, 2015; U.S. Non-Provisional
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CA 3056101 2019-09-20
=
A
Patent Application No. 14/523,089 filed October 24, 2014; U.S. Non-Provisional
Patent Application No. 14/327,208 filed July 9, 2014; U.S. Non-Provisional
Patent Application No. 15/003,515 filed January 21, 2016; U.S. Non-Provisional
Patent Application No. 15/003,524 filed January 21, 2016; U.S. Non-Provisional
Patent Application No. 15/052,125 filed February 24, 2016; U.S. Non-
Provisional Patent Application No. 15/053,965 filed February 25, 2016; U.S.
Provisional patent application Serial No. 62/360,864 filed July 11, 2016 and
entitled "METHOD AND APPARATUS TO ACCOUNT FOR TRANSPONDER
TAGGED OBJECTS USED DURING CLINICAL PROCEDURES, EMPLOYING
A SHIELDED RECEPTACLE"; U.S. Provisional patent application Serial No.
62/360,866 filed July 11, 2016 and entitled "METHOD AND APPARATUS TO
ACCOUNT FOR TRANSPONDER TAGGED OBJECTS USED DURING
CLINICAL PROCEDURES EMPLOYING A SHIELDED RECEPTACLE WITH
ANTENNA"; and U.S. Provisional patent application Serial No. 62/360,868 filed
July 11, 2016 and entitled "METHOD AND APPARATUS TO ACCOUNT FOR
TRANSPONDER TAGGED OBJECTS USED DURING CLINICAL
PROCEDURES, FOR EXAMPLE INCLUDING COUNT IN AND/OR COUNT
OUT AND PRESENCE DETECTION", are each incorporated herein by
reference, in their entirety. Aspects of the embodiments can be modified, if
necessary, to employ systems, circuits and concepts of the various patents,
applications and publications to provide yet further embodiments.
These and other changes can be made to the embodiments in
light of the above-detailed description. In general, in the following claims,
the
terms used should not be construed to limit the claims to the specific
embodiments disclosed in the specification and the claims, but should be
construed to include all possible embodiments along with the full scope of
equivalents to which such claims are entitled. Accordingly, the claims are not
limited by the disclosure.
32
CA 3056101 2019-09-20
