Note: Descriptions are shown in the official language in which they were submitted.
CA 03033986 2019-02-14
METHODS OF ACOUSTICALLY COMMUNICATING AND WELLS THAT
UTILIZE THE METHODS
Field of the Disclosure
[0001] The present disclosure relates generally to methods of acoustically
communicating
and/or to wells that utilize the methods.
Background of the Disclosure
[0002] An acoustic wireless network may be utilized to wirelessly transmit
an acoustic
signal, such as a vibration, via a tone transmission medium. In general, a
given tone
transmission medium will only permit communication within a certain frequency
range; and,
in some systems, this frequency range may be relatively small. Such systems
may be referred
to herein as spectrum-constrained systems. An example of a spectrum-
constrained system is
a well, such as a hydrocarbon well, that includes a plurality of communication
nodes spaced-
apart along a length thereof.
[0003] Under certain circumstances, it may be desirable to transmit data,
in the form of
acoustic signals, within such a spectrum-constrained environment. However,
conventional
data transmission mechanisms often cannot be effectively utilized. Thus, there
exists a need
for improved methods of acoustically communicating and/or for wells that
utilize the methods.
Summary of the Disclosure
[0004] Methods of acoustically communicating and wells that utilize the
methods are
disclosed herein. The methods generally utilize an acoustic wireless network
including a
plurality of nodes spaced-apart along a length of a tone transmission medium.
In some
embodiments, the methods include methods of communicating when the acoustic
wireless
network is spectrum-constrained. In these embodiments, the methods include
encoding an
encoded character with an encoding node of the plurality of nodes. The
encoding includes
selecting a first frequency based upon a first predetermined lookup table and
the encoded
character, and the transmitting a first transmitted acoustic tone at the first
frequency. The
encoding further includes selecting a second frequency based upon a second
predetermined
lookup table and the encoded character, and the transmitting a second
transmitted acoustic
tone at the second frequency. These methods also include decoding a decoded
character with
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a decoding node of the plurality of nodes. The decoding includes receiving a
first received
acoustic tone, calculating a first frequency distribution for the first
received acoustic tone, and
determining a first decoded character distribution for the decoded character.
The decoding
also includes receiving a second received acoustic tone, calculating a second
frequency
distribution for the second received acoustic tone, and determining a second
decoded character
distribution for the decoded character. The decoding further includes
identifying the decoded
character based upon the first decoded character distribution and the second
decoded character
distribution.
[0005] In other embodiments, the methods include methods of determining a
major
frequency of a received acoustic tone transmitted via the tone transmission
medium. These
methods include receiving a received acoustic tone for a tone receipt time and
estimating a
frequency of the received acoustic tone. These methods also include separating
the tone
receipt time into a plurality of time intervals and calculating a frequency
variation within each
of the time intervals. These methods further include selecting a subset of the
plurality of time
intervals within which the frequency variation is less than a threshold
frequency variation and
averaging a plurality of discrete frequency values within the subset of the
plurality of time
intervals to determine the major frequency of the received acoustic tone.
[0006] In other embodiments, the methods include methods of conserving
power in the
acoustic wireless network. These methods include repeatedly and sequentially
cycling a given
node of the plurality of nodes for a plurality of cycles by entering a lower
power state for a
lower power state duration and subsequently transitioning to a listening state
for a listening
state duration. The low-power state duration is greater than the listening
state duration. These
methods also include transmitting, during the cycling and via a tone
transmission medium, a
transmitted acoustic tone for a tone transmission duration, receiving a
received acoustic tone,
and, responsive to the receiving, interrupting the cycling by transitioning
the given node to an
active state. The tone transmission duration is greater than the low-power
state duration such
that the acoustic wireless network detects the transmitted acoustic tone
regardless of when the
transmitting is initiated.
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Brief Description of the Drawings
[0007] Fig. 1 is a schematic representation of a well configured to utilize
the methods
according to the present disclosure.
[0008] Fig. 2 is a flowchart depicting methods, according to the present
disclosure, of
communicating in an acoustic wireless network that is spectrum-constrained.
[0009] Fig. 3 is a flowchart depicting methods, according to the present
disclosure, of
encoding an encoded character.
[0010] Fig. 4 is a flowchart depicting methods, according to the present
disclosure, of
decoding a decoded character.
[0011] Fig. 5 is an example of a first predetermined lookup table that may
be utilized with
the methods according to the present disclosure.
[0012] Fig. 6 is an example of a second predetermined lookup table that may
be utilized
with the methods according to the present disclosure.
[0013] Fig. 7 is an example of a plurality of encoded characters and a
corresponding
plurality of frequencies that may be utilized to convey the encoded
characters.
[0014] Fig. 8 is an example of a plurality of encoded characters and a
corresponding
plurality of frequencies that may be utilized to convey the encoded
characters.
[0015] Fig. 9 is a flowchart depicting methods, according to the present
disclosure, of
determining a major frequency of a received acoustic tone.
[0016] Fig. 10 is a plot illustrating a received amplitude of a plurality
of received acoustic
tones as a function of time.
[0017] Fig. 11 is a plot illustrating a received amplitude of an acoustic
tone from Fig. 10.
[0018] Fig. 12 is a plot illustrating frequency variation in the received
acoustic tone of
Fig. 11.
[0019] Fig. 13 is a table illustrating histogram data that may be utilized
to determine the
major frequency of the received acoustic tone of Figs. 11-12.
[0020] Fig. 14 is a table illustrating a mechanism, according to the
present disclosure, by
which the major frequency of the acoustic tone of Figs. 11-12 may be selected.
[0021] Fig. 15 is a flowchart depicting methods, according to the present
disclosure, of
conserving power in an acoustic wireless network.
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[0022] Fig. 16 is a schematic illustration of the method of Fig. 15.
Detailed Description and Best Mode of the Disclosure
[0023] Figs. 1-16 provide examples of methods 200, 300, and/or 400,
according to the
present disclosure, and/or of wells 20 including acoustic wireless networks 50
that may
include and/or utilize the methods. Elements that serve a similar, or at least
substantially
similar, purpose are labeled with like numbers in each of Figs. 1-16, and
these elements may
not be discussed in detail herein with reference to each of Figs. 1-16.
Similarly, all elements
may not be labeled in each of Figs. 1-16, but reference numerals associated
therewith may be
utilized herein for consistency. Elements, components, and/or features that
are discussed
herein with reference to one or more of Figs. 1-16 may be included in and/or
utilized with any
of Figs. 1-16 without departing from the scope of the present disclosure. In
general, elements
that are likely to be included in a particular embodiment are illustrated in
solid lines, while
elements that are optional are illustrated in dashed lines. However, elements
that are shown
in solid lines may not be essential and, in some embodiments, may be omitted
without
departing from the scope of the present disclosure.
100241 Fig. 1 is a schematic representation of a well 20 configured to
utilize methods 200,
300, and/or 400 according to the present disclosure. Well 20 includes a
wellbore 30 that
extends within a subsurface region 90. Wellbore 30 also may be referred to
herein as
extending between a surface region 80 and subsurface region 90 and/or as
extending within a
subterranean formation 92 that extends within the subsurface region.
Subterranean formation
92 may include a hydrocarbon 94. Under these conditions, well 20 also may be
referred to
herein as, or may be, a hydrocarbon well 20, a production well 20, and/or an
injection well
20.
[0025j Well 20 also includes an acoustic wireless network 50. The acoustic
wireless
network also may be referred to herein as a downhole acoustic wireless network
50 and
includes a plurality of nodes 60, which are spaced-apart along a tone
transmission medium
100 that extends along a length of wellbore 30. In the context of well 20,
tone transmission
medium 100 may include a dovvnhole tubular 40 that may extend within wellbore
30, a
wellbore fluid 32 that may extend within wellbore 30, a portion of subsurface
region 90 that
is proximal wellbore 30, a portion of subterranean formation 92 that is
proximal wellbore 30,
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and/or a cement 34 that may extend within wellbore 30 and/or that may extend
within an
annular region between wellbore 30 and downhole tubular 40. Downhole tubular
40 may
define a fluid conduit 44.
[0026] Nodes 60 may include one or more encoding nodes 62, which may be
configured
to generate an acoustic tone 70 and/or to induce the acoustic tone within tone
transmission
medium 100. Nodes 60 also may include one or more decoding nodes 64, which may
be
configured to receive acoustic tone 70 from the tone transmission medium. A
given node 60
may function as both an encoding node 62 and a decoding node 64 depending upon
whether
the given node is transmitting an acoustic tone (i.e., functioning as the
encoding node) or
receiving the acoustic tone (i.e., functioning as the decoding node). Stated
another way, the
given node may include both encoding and decoding functionality, or
structures, with these
structures being selectively utilized depending upon whether or not the given
node is encoding
the acoustic tone or decoding the acoustic tone.
[0027] In wells 20, transmission of acoustic tone 70 may be along a length
of wellbore
30. As such, the transmission of the acoustic tone may be linear, at least
substantially linear,
and/or directed, such as by tone transmission medium 100. Such a configuration
may be in
contrast to more conventional wireless communication methodologies, which
generally may
transmit a corresponding wireless signal in a plurality of directions, or even
in every direction.
[0028] As illustrated in Fig. 1, acoustic wireless network 50 may include
nodes 60 that
are positioned within wellbore 30. As such, these nodes may be inaccessible,
or at least
difficult to access. Thus, limiting power consumption, as is discussed herein
with reference
to methods 400 of Figs. 15-16, may be important to the operation and/or
longevity of the
acoustic wireless network.
[0029] Method 200, 300, and/or 400, which are discussed in more detail
herein, are
disclosed in the context of well 20, such as a hydrocarbon well. However, it
is within the
scope of the present disclosure that these methods may be utilized to
communicate via an
acoustic tone, such as described in methods 200 of Figs. 2-8, to determine a
major frequency
of a received acoustic tone, such as described in methods 300 of Figs. 9-14,
and/or to conserve
power, such as described in methods 300 of Figs. 15-16, in any suitable
acoustic wireless
network. As examples, methods 200, 300, and/or 400 may be utilized with a
corresponding
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acoustic wireless network in the context of a subsea well and/or in the
context of a subsea
tubular that extends within a subsea environment. Under these conditions, the
tone
transmission medium may include, or be, the subsea tubular and/or a subsea
fluid that extends
within the subsea environment, proximal the subsea tubular, and/or within the
subsea tubular.
As another example, methods 200, 300 and/or 400 may be utilized with a
corresponding
acoustic wireless network in the context of a surface tubular that extends
within the surface
region. Under these conditions, the tone transmission medium may include, or
be, the surface
tubular and/or a fluid that extends within the surface region, proximal the
surface tubular,
and/or within the surface tubular,
[0030] Fig. 2 is a flowchart depicting methods 200, according to the
present disclosure,
of communicating in an acoustic wireless network that is spectrum-constrained.
The acoustic
wireless network includes a plurality of nodes spaced-apart along a length of
a tone
transmission medium. Examples of the acoustic wireless network are disclosed
herein with
reference to acoustic wireless network 50 of Fig. 1. Examples of the tone
transmission
medium are disclosed herein with reference to tone transmission medium 100 of
Fig. 1.
[0031] With the above in mind, methods 200 may include establishing
predetermined
lookup tables at 210 and include encoding an encoded character at 220, which
is illustrated in
more detail in Fig. 3. Methods 200 further may include conveying an acoustic
tone at 230
and include decoding a decoded character at 240, which is illustrated in more
detail in Fig. 4.
Methods 200 also may include repeating at least a portion of the methods at
280, and Figs. 5-
8 provide schematic examples of various steps of methods 200.
[0032] During operation of an acoustic wireless network, such as acoustic
wireless
network 50 of Fig. 1, methods 200 may be utilized to transmit and/or convey
one or more
characters and/or pieces of information along, or along the length of, the
tone transmission
medium. As an example, and as discussed in more detail herein, a first
predetermined lookup
table 201, as illustrated in Fig. 5, and a second predetermined lookup table
202, as illustrated
in Fig. 6, may correlate a plurality of characters, or encoded characters,
(e.g., characters A-Q
in Figs. 5-6) to a plurality of frequencies, or frequency ranges (e.g.,
frequencies F -F 17 in Figs.
5-6). Under these conditions, a character, such as a "P," may be selected for
transmission
along the length of the tone transmission medium, and methods 200 may be
utilized to encode
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this character into a corresponding frequency and subsequently to decode this
character from
the corresponding frequency. In the example of Figs. 5-6, the "P÷ corresponds
to F16 in first
predetermined lookup table 201 and to F8 in second predetermined lookup table
202. Thus,
the encoding at 220 may include transmitting frequency F16, via the tone
transmission medium
and with an encoding node, and subsequently transmitting frequency Fg, via the
tone
transmission medium and with the encoding node, as illustrated in Fig. 7. The
decoding at
240 then may include receiving frequency F16 and subsequently receiving
frequency F8, with
a decoding node and from the tone transmission medium, and utilizing first
predetermined
lookup table 201 and second predetermined lookup table 202, respectively, to
decode the
received frequencies into their corresponding character (e.g., P1 and P2, as
illustrated in Fig.
8). This process may be repeated any suitable number of times to transmit any
suitable number
of characters, or encoded characters, along the length of the tone
transmission medium, as
illustrated in Figs. 7-8 with the corresponding frequencies for transmission
of the characters
P-A-I-L.
[0033] Establishing predetermined lookup tables at 210 may include
establishing any
suitable predetermined lookup table. This may include establishing the first
predetermined
lookup table and the second predetermined lookup table, and these
predetermined lookup
tables may be utilized during the encoding at 220 and/or during the decoding
at 240. With
this in mind, the establishing at 210, when performed, may be performed prior
to the encoding
at 220 and/or prior to the decoding at 240.
[0034] The establishing at 210 may be accomplished in any suitable manner.
As an
example, the establishing at 210 may include obtaining the first predetermined
lookup table
and/or the second predetermined lookup table from any suitable source, such as
from a
database of lookup tables.
[0035] As another example, the establishing at 210 may include generating,
or creating,
the first predetermined lookup table and/or the second predetermined lookup
table. This may
include transmitting, at 212, a calibration signal via the tone transmission
medium and with
an encoding node of the plurality of nodes. This also may include receiving,
at 214, the
calibration signal from the tone transmission medium and with a decoding node
of the
plurality of nodes. This further may include determining, at 216, at least one
acoustic
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characteristic of the tone transmission medium. The at least one
characteristic of the tone
transmission medium may be determined and/or quantified based, at least in
part, on the
transmitting at 212 and/or on the receiving at 214.
[0036] Under
these conditions, the establishing at 210 may include establishing the
predetermined lookup tables based, at least in part, on the at least one
acoustic characteristic
of the tone transmission medium. As a more specific example, the establishing
at 210 may
include determining a bandwidth for acoustic communication within the tone
transmission
medium. This may include determining a bandwidth, or frequency range, within
which the
tone transmission medium has less than a threshold ambient acoustic noise
level and/or within
which the transmitting at 212 and the receiving at 214 may be performed with
less than a
threshold loss in signal quality, in signal amplitude, and/or in signal
intensity between the
encoding node and the decoding node.
[0037] An
example of first predetermined lookup table 201 is illustrated in Fig. 5,
while
an example of second predetermined lookup table 202 is illustrated in Fig. 6.
As illustrated
in Figs. 5-6, predetel _____________________________________________ mined
lookup tables 201 and 202 generally correlate a plurality of
characters, or encoded characters, such as the letters A through Q that are
illustrated in the
first row of Figs. 5-6, with a corresponding plurality of frequencies, or
frequency ranges, such
as frequencies F1-F 1 7 that are illustrated in the second row of Figs. 5-6.
[0038] First
predetermined lookup table 201 and second predetermined lookup table 202
differ from one another. More specifically, and as illustrated, the frequency
that correlates to
a given character differs between first predetermined lookup table 201 and
second
predetermined lookup table 202. Additionally or alternatively, the first
predetermined lookup
table and the second predetermined lookup table may be configured such that,
for a given
character, the corresponding first frequency, as established by first
predetermined lookup table
201, is unequal to and/or not a harmonic of the corresponding second
frequency, as established
by second predetermined lookup table 202. Such a configuration may increase an
accuracy
of communication when the tone transmission medium transmits one frequency
more
effectively, with less noise, and/or with less attenuation than another
frequency.
[0039] It is
within the scope of the present disclosure that first predetermined lookup
table
201 and second predetermined lookup table 202 may utilize the same encoded
characters and
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the same frequencies, or frequency ranges. Under these conditions, a different
frequency, or
frequency range, may be correlated to each encoded character in first
predetermined lookup
table 201 when compared to second predetermined lookup table 202. Additionally
or
alternatively, it is also within the scope of the present disclosures that at
least one frequency,
or frequency range, may be included in one of the first predetermined lookup
table and the
second predetermined lookup table but not in the other lookup table.
[0040] The plurality of frequencies utilized in the first predetermined
lookup table and in
the second predetermined lookup table, including the first frequency and/or
the second
frequency, may have any suitable value and/or may be within any suitable
frequency range.
As examples, each frequency in the plurality of frequencies may be at least 10
kilohertz (kHz),
at least 25 kHz, at least 50 kHz, at least 60 kHz, at least 70 kHz, at least
80 kHz, at least 90
kHz, at least 100 kHz, at least 200 kHz, at least 250 kHz, at least 400 kHz,
at least 500 kHz,
and/or at least 600 kHz. Additionally or alternatively, each frequency in the
plurality of
frequencies may be at most 1000 kHz (1 megahertz), at most 800 kHz, at most
600 kHz, at
most 400 kHz, at most 200 kHz, at most 150 kHz, at most 100 kHz, and/or at
most 80 kHz.
[0041] Encoding the encoded character at 220 may include encoding the
encoded
character with the encoding node. As illustrated in Fig. 3, the encoding at
220 includes
selecting a first frequency for a first transmitted acoustic tone at 222,
transmitting the first
transmitted acoustic tone at 224, selecting a second frequency for a second
transmitted
acoustic tone at 226, and transmitting the second transmitted acoustic tone at
228.
[0042] Selecting the first frequency for the first transmitted acoustic
tone at 222 may
include selecting based, at least in part, on the encoded character.
Additionally or
alternatively, the selecting at 222 also may include selecting from the first
predetermined
lookup table. The first frequency may be correlated to the encoded character
in the first
predetermined lookup table. As an example, and with reference to Fig. 5, the
first encoded
character may be a "P," and the first frequency may be F16, as indicated in
the leftmost box of
Fig. 7. The first predetermined lookup table may provide a one-to-one
correspondence
between the first frequency and the encoded character. Stated another way,
each encoded
character, and each frequency, may be utilized once and only once in the first
predetermined
lookup table.
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[0043] Transmitting the first transmitted acoustic tone at 224 may include
transmitting the
first transmitted acoustic tone at the first frequency. Additionally or
alternatively, the
transmitting at 224 also may include transmitting the first transmitted
acoustic tone via and/or
utilizing the tone transmission medium. The transmitting at 224 further may
include
transmitting for a first tone-transmission duration.
[0044] The transmitting at 224 may be accomplished in any suitable manner.
As an
example, the transmitting at 224 may include inducing the first acoustic tone,
within the tone
transmission medium, with an encoding node transmitter of the acoustic
wireless network.
Examples of the encoding node transmitter include any suitable structure
configured to induce
a vibration within the tone transmission medium, such as a piezoelectric
encoding node
transmitter, an electromagnetic acoustic transmitter, a resonant
microelectromechanical
system (MEMS) transmitter, a non-resonant MEMS transmitter, and/or a
transmitter array.
[0045] Selecting the second frequency for the second transmitted acoustic
tone at 226 may
include selecting based, at least in part, on the encoded character.
Additionally or
alternatively, the selecting at 226 also may include selecting from the second
predetermined
lookup table. In general, the second predetermined lookup table is different
from the first
predetermined lookup table and/or the second frequency is different from the
first frequency.
The second frequency may be correlated to the encoded character in the second
predetermined
lookup table. As an example, and with reference to Fig. 6, the second
frequency may be F8
when the encoded character is "P," as indicated in the leftmost box of Fig. 7.
The second
predetermined lookup table may provide a one-to-one correspondence between the
second
frequency and the encoded character. Stated another way, each encoded
character, and each
frequency, may be utilized once and only once in the second predetermined
lookup table.
[0046] Transmitting the second transmitted acoustic tone at 228 may include
transmitting
the first transmitted acoustic tone at the second frequency. Additionally or
alternatively, the
transmitting at 228 also may include transmitting the second transmitted
acoustic tone via
and/or utilizing the tone transmission medium. The transmitting at 228 further
may include
transmitting for a second tone-transmission duration.
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[0047] The transmitting at 228 may be accomplished in any suitable manner.
As an
example, the transmitting at 228 may include inducing the second acoustic
tone, within the
tone transmission medium, with the encoding node transmitter.
[00481 Conveying the acoustic tone at 230 may include conveying in any
suitable manner.
As an example, the decoding node may be spaced-apart from the encoding node
such that the
tone transmission medium extends between, or spatially separates, the encoding
node and the
decoding node. Under these conditions, the conveying at 230 may include
conveying the first
transmitted acoustic tone and/or conveying the second transmitted acoustic
tone, via the tone
transmission medium, from the encoding node to the decoding node.
[0049] The conveying at 230 further may include modifying the first
transmitted acoustic
tone, via a first interaction with the tone transmission medium, to generate a
first received
acoustic tone. Additionally or alternatively, the conveying at 230 may include
modifying the
second transmitted acoustic tone, via a second interaction with the tone
transmission medium,
to generate a second received acoustic tone. The modifying may include
modifying in any
suitable manner and may be active (i.e., purposefully performed) or passive
(i.e., inherently
performed as a result of the conveying). Examples of the modifying include
modification of
one or more of an amplitude of the first and/or second transmitted acoustic
tone, a phase of
the first and/or second transmitted acoustic tone, a frequency of the first
and/or second
transmitted acoustic tone, and/or a wavelength of the first and/or second
transmitted acoustic
tone. Another example of the modifying includes introducing additional
frequency
components into the first and/or second transmitted acoustic tone, Examples of
mechanisms
that may produce and/or generate the modifying include tone reflections,
ringing, and/or tone
recombination at the encoding node, within the tone transmission medium,
and/or at the
decoding node.
[0050] Decoding the decoded character at 240 may include decoding with the
decoding
node. As illustrated in Fig. 4, the decoding at 240 includes receiving, at
242, the first received
acoustic tone, calculating, at 244, a first frequency distribution, and
determining, at 250, a first
decoded character distribution. The decoding at 240 also includes receiving,
at 258, a second
received acoustic tone, calculating, at 262, a second frequency distribution,
and determining,
at 268, a second decoded character distribution. The decoding at 240 further
includes
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identifying, at 274, the decoded character. The decoding at 240 additionally
or alternatively
may include performing any suitable portion of methods 300, which are
discussed herein with
reference to Figs. 9-14.
[0051] Receiving the first received acoustic tone at 242 may include
receiving the first
received acoustic tone with the decoding node and/or from the tone
transmission medium and
may be performed subsequent to, or responsive to, the transmitting at 224. The
receiving at
242 may include receiving the first received acoustic tone for a first tone-
receipt duration.
[0052] The receiving at 242 may include receiving with any suitable
decoding node that
is configured to receive the first received acoustic tone from the tone
transmission medium.
As examples, the receiving at 242 may include receiving with, via, and/or
utilizing a
piezoelectric decoding node receiver, a piezoresistive receiver, a resonant
MEMS receiver, a
non-resonant MEMS receiver, and/or a receiver array.
[0053] Calculating the first frequency distribution at 244 may include
calculating the first
frequency distribution for, or of, the first received acoustic tone and may be
accomplished in
any suitable manner. As examples, the calculating at 244 may include
performing a Fourier
transform of the first received acoustic tone, performing a fast Fourier
transform of the first
received acoustic tone, performing a discrete Fourier transform of the first
received acoustic
tone, performing a wavelet transform of the first received acoustic tone,
performing a multiple
least squares analysis of the first received acoustic tone, and/or performing
a polyhistogram
analysis of the first received acoustic tone. Examples of the polyhistogram
analysis are
disclosed herein with reference to methods 300 of Fig. 9.
[0054] It is within the scope of the present disclosure that the first
received acoustic tone
may include a plurality of first frequency components. These first frequency
components may
be generated during the transmitting at 224, during the conveying at 230,
and/or during the
receiving at 242, and examples of mechanisms that may generate the first
frequency
components are discussed herein with reference to the conveying at 230.
[0055] When the first received acoustic tone includes the plurality of
first frequency
components, the calculating at 244 may include calculating, at 246, a relative
magnitude of
each of the plurality of first frequency components and/or calculating, at
248, a histogram of
the plurality of first frequency components.
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[0056] Determining the first decoded character distribution at 250 may
include
determining the first decoded character distribution from the first frequency
distribution
and/or from the first predetermined lookup table. As an example, the plurality
of first
frequency components, as calculated during the calculating at 244, may
correspond to a
plurality of first received characters within first predetermined lookup table
201 of Fig. 5.
Stated another way, the determining at 250 may include determining which
character from the
first predetermined lookup table corresponds to each frequency component in
the plurality of
first frequency components.
[0057] Under these conditions, the determining at 250 may include
calculating, at 252, a
relative probability that the first received acoustic tone represents each
first received character
in the plurality of first received characters and/or calculating, at 254, a
histogram of the
plurality of first received characters. Additionally or alternatively, the
determining at 250
may include mapping, at 256, each first frequency component in the plurality
of first
frequency components to a corresponding character in the first predetermined
lookup table.
[0058] Receiving the second received acoustic tone at 258 may include
receiving the
second received acoustic tone with the decoding node and/or from the tone
transmission
medium and may be performed subsequent, or responsive, to the transmitting at
228. The
receiving at 258 may include receiving the second received acoustic tone for a
second tone-
receipt duration.
[0059] Calculating the second frequency distribution at 262 may include
calculating the
second frequency distribution for, or of, the second received acoustic tone
and may be
accomplished in any suitable manner. As examples, the calculating at 260 may
include
perfoiming a Fourier transform of the second received acoustic tone,
performing a fast Fourier
transform of the second received acoustic tone, performing a discrete Fourier
transform of the
second received acoustic tone, performing a wavelet transform of the second
received acoustic
tone, performing a multiple least squares analysis of the second received
acoustic tone, and/or
performing a polyhistogram analysis of the second received acoustic tone.
Examples of the
polyhistogram analysis are disclosed herein with reference to methods 300 of
Fig. 9.
[0060] Similar to the first received acoustic tone, the second received
acoustic tone may
include a plurality of second frequency components. These second frequency
components
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may be generated during the transmitting at 228, during the conveying at 230,
and/or during
the receiving at 258, as discussed herein with reference to the calculating at
244.
[0061] When the second received acoustic tone includes the plurality of
second frequency
components, the calculating at 260 may include calculating, at 262, a relative
magnitude of
each of the plurality of second frequency components and/or calculating, at
264, a histogram
of the plurality of second frequency components.
[0062] Determining the second decoded character distribution at 268 may
include
determining the second decoded character distribution from the second
frequency distribution
and/or from the second predetermined lookup table. As an example, the
plurality of second
frequency components, as calculated during the calculating at 260, may
correspond to a
plurality of second received characters within second predetermined lookup
table 202 of Fig.
6. Stated another way, the determining at 266 may include determining which
character from
the second predetermined lookup table corresponds to each frequency component
in the
plurality of second frequency components.
[0063] Under these conditions, the determining at 266 may include
calculating, at 268, a
relative probability that the second received acoustic tone represents each
second received
character in the plurality of second received characters and/or calculating,
at 270, a histogram
of the plurality of second received characters. Additionally or alternatively,
the determining
at 266 may include mapping, at 272, each second frequency component in the
plurality of
second frequency components to a corresponding character in the second
predetermined
lookup table.
[0064] Identifying the decoded character at 274 may include identifying the
decoded
character based, at least in part, on the first decoded character distribution
and the second
decoded character distribution. The identifying at 274 may be accomplished in
any suitable
manner. As an example, the identifying at 274 may include identifying which
character in the
first decoded character distribution has the highest probability of being the
encoded character
and/or identifying which character in the second decoded character
distribution has the highest
probability of being the encoded character.
[0065] As a more specific example, the identifying at 274 may include
combining the first
decoded character distribution with the second decoded character distribution
to produce
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and/or generate a composite decoded character distribution and identifying, as
indicated at
276, the highest probability character from the composite decoded character
distribution. The
first decoded character distribution and the second decoded character
distribution may be
combined in any suitable manner. As an example, the first decoded character
distribution and
the second decoded character distribution may be summed. As another example,
the first
decoded character distribution and the second decoded character distribution
may be
combined utilizing a one-and-one-half moment method. As another more specific
example,
and as indicated in Fig. 4 at 278, the identifying at 274 may include
selecting a most common
character from the first decoded character distribution and from the second
decoded character
distribution.
[0066] Repeating at least the portion of the methods at 280 may include
repeating any
suitable portion of methods 200 in any suitable order. As an example, the
encoding node may
be a first node of the plurality of nodes, and the decoding node may be a
second node of the
plurality of nodes. Under these conditions, the repeating at 280 may include
repeating the
encoding at 220 with the second node and repeating the decoding at 240 with a
third node of
the plurality of nodes, such as to transmit the encoded character along the
length of the tone
transmission medium. This process may be repeated a plurality of times to
propagate the
encoded character among the plurality of spaced-apart nodes. The third node
may be spaced-
apart from the second node and/or from the first node. Additionally or
alternatively, the
second node may be positioned between the first node and the third node along
the length of
the tone transmission medium.
[0067] As another example, the encoded character may be a first encoded
character, and
the decoded character may be a first decoded character. Under these
conditions, the repeating
at 280 may include repeating the encoding at 220 to encode a second encoded
character and
repeating the decoding at 240 to decode a second decoded character. This is
illustrated in
Figs. 7-8, wherein the characters P-A-I-L sequentially are encoded, as
illustrated in Fig. 7,
utilizing corresponding frequencies from the first and second predetermined
lookup tables of
Figs. 5 and 6. The characters subsequently are decoded, as illustrated in Fig.
8, by comparing
the received frequencies to the frequencies from the first and second
predetermined lookup
tables.
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[0068] Methods 200 have been described herein as utilizing two
predetermined lookup
tables (e.g., first predetermined lookup table 201 of Fig. 5 and second
predetermined lookup
table 202 of Fig. 6). However, it is within the scope of the present
disclosure that methods
200 may include and/or utilize any suitable number of frequencies, and
corresponding
predetermined lookup tables, for a given encoded character. As examples, the
encoding at
220 may include selecting a plurality of frequencies for a plurality of
transmitted acoustic
tones from a corresponding plurality of lookup tables and transmitting the
plurality of
transmitted acoustic tones via the tone transmission medium. As additional
examples, the
decoding at 240 may include receiving a plurality of received acoustic tones,
calculating a
plurality of frequency distributions from the plurality of received acoustic
tones, determining,
from the plurality of frequency distributions and the plurality of
predetermined lookup tables,
a plurality of decoded character distributions, and identifying the decoded
character based, at
least in part, on the plurality of decoded character distributions. The
plurality of decoded
character distributions may include any suitable number of decoded character
distributions,
including at least 3, at least 4, at least 6, at least 8, or at least 10
decoded character distributions.
[0069] It is within the scope of the present disclosure that methods 200
may be performed
utilizing any suitable tone transmission medium and/or in any suitable
environment and/or
context, including those that are disclosed herein. As an example, and when
methods 200 are
performed within a well, such as well 20 of Fig. 1, methods 200 further may
include drilling
wellbore 30. Stated another way, methods 200 may be performed while the
wellbore is being
formed, defined, and/or drilled. As another example, methods 200 further may
include
producing a reservoir fluid from subterranean formation 92. Stated another
way, methods 200
may be performed while the reservoir fluid is being produced from the
subterranean
formation.
100701 As discussed herein, the encoding at 220 and/or the decoding at 240
may utilize
predetermined lookup tables, such as first predetermined lookup table 201
and/or second
predetermined lookup table 202, to map predetermined frequencies, or frequency
ranges, to
predetermined characters, or encoded characters. As such, methods 200 may be
performed
without, without utilizing, and/or without the use of a random, or
pseudorandom, number
generator.
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[0071] Fig. 9 is a flowchart depicting methods 300, according to the
present disclosure,
of determining a major frequency of a received acoustic tone that is
transmitted via a tone
transmission medium, while Figs. 10-14 illustrate various steps that may be
performed during
methods 300. Methods 300 may be performed utilizing any suitable structure
and/or
structures. As an example, methods 300 may be utilized by an acoustic wireless
network,
such as acoustic wireless network 50 of Fig. 1. Under these conditions,
methods 300 may be
utilized to communicate along a length of wellbore 30.
[0072] Methods 300 include receiving a received acoustic tone at 310,
estimating a
frequency of the received acoustic tone at 320, and separating a tone receipt
time into a
plurality of time intervals at 330. Methods 300 also include calculating a
frequency variation
at 340, selecting a subset of the plurality of time intervals at 350, and
averaging a plurality of
discrete frequency values at 360. Methods 300 further may include transmitting
a transmitted
acoustic tone at 370.
[0073] Receiving the received acoustic tone at 310 may include receiving
with a decoding
node of an acoustic wireless network. Additionally or alternatively, the
receiving at 310 may
include receiving from the tone transmission medium and/or receiving for a
tone receipt time.
The receiving at 310 may include receiving for any suitable tone receipt time.
As examples,
the tone receipt time may be at least 1 microsecond, at least 10 microseconds,
at least 25
microseconds, at least 50 microseconds, at least 75 microseconds, or at least
100
microseconds. The receiving at 310 also may include receiving at any suitable
frequency, or
tone frequency. Examples of the tone frequency include frequencies of at least
10 kilohertz
(kHz), at least 25 kHz, at least 50 kHz, at least 60 kHz, at least 70 kHz, at
least 80 kHz, at
least 90 kHz, at least 100 kHz, at least 200 kHz, at least 250 kHz, at least
400 kHz, at least
500 kHz, and/or at least 600 kHz. Additionally or alternatively, the tone
frequency may be at
most 1 megahertz (MHz), at most 800 kHz, at most 600 kHz, at most 400 kHz, at
most 200
kHz, at most 150 kHz, at most 100 kHz, and/or at most 80 kHz.
[0074] The receiving at 310 may include receiving with any suitable
decoding node, such
as decoding node 64 of Fig. 1. Additionally or alternatively, the receiving at
310 may include
receiving with an acoustic tone receiver. Examples of the acoustic tone
receiver include a
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piezoelectric tone receiver, a piezoresistive tone receiver, a resonant MEMS
tone receiver, a
non-resonant MEMS tone receiver, and/or a receiver array.
[0075] An example of a plurality of received acoustic tones is illustrated
in Fig. 10, while
an example of a single received acoustic tone is illustrated in Fig. 11. Figs.
10-11 both
illustrate amplitude of the received acoustic tone as a function of time
(e.g., the tone receipt
time). As illustrated in Figs. 10-11, the amplitude of the received acoustic
tone may vary
significantly during the tone receipt time. This variation may be caused by
non-idealities
within the tone transmission medium and/or with the tone transmission process.
Examples of
these non-idealities are discussed herein and include acoustic tone reflection
points within the
tone transmission medium, generation of harmonics during the tone transmission
process,
ringing within the tone transmission medium, and/or variations in a velocity
of the acoustic
tone within the tone transmission medium. Collectively, these non-idealities
may make it
challenging to determine, to accurately determine, and/or to reproducibly
determine the major
frequency of the received acoustic tone, and methods 300 may facilitate this
determination.
100761 Estimating the frequency of the received acoustic tone at 320 may
include
estimating the frequency of the received acoustic tone as a function of time
and/or during the
tone receipt time. This may include estimating a plurality of discrete
frequency values
received at a corresponding plurality of discrete times within the tone
receipt time and may
be accomplished in any suitable manner.
[0077] As an example, the received acoustic tone may include, or be, a
received acoustic
wave that has a time-varying amplitude within the tone receipt time, as
illustrated in Figs. 10-
11. The time-varying amplitude may define an average amplitude, and the
estimating at 320
may include measuring a cycle time between the time-varying amplitude and the
average
amplitude, measuring a period of individual cycles of the received acoustic
wave, and/or
measuring a plurality of zero-crossing times of the received acoustic wave.
[0078] The estimating at 320 may be utilized to generate a dataset that
represents the
frequency of the received acoustic tone as a function of time during the tone
receipt time. An
example of such a dataset is illustrated in Fig. 12. As may be seen in Fig.
12, the frequency
of the received acoustic tone includes time regions where there is a
relatively higher amount
of variation, such as the time regions from TO to Ti and from T2 to T3 in Fig.
12, and a time
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region where there is a relatively lower amount of variation, such as time
region from Ti to
T2 in Fig. 12.
[0079] Separating the tone receipt time into the plurality of time
intervals at 330 may
include separating such that each time interval in the plurality of time
intervals includes a
subset of the plurality of discrete frequency values that was received and/or
determined during
that time interval. It is within the scope of the present disclosure that each
time interval in the
plurality of time intervals may be less than a threshold fraction of the tone
receipt time.
Examples of the threshold fraction of the tone receipt time include threshold
fractions of less
than 20%, less than 15%, less than 10%, less than 5%, or less than 1%. Stated
another way,
the separating at 330 may include separating the tone receipt time into at
least a threshold
number of time intervals. Examples of the threshold number of time intervals
includes at least
5, at least 7, at least 10, at least 20, or at least 100 time intervals. It is
within the scope of the
present disclosure that a duration of each time interval in the plurality of
time intervals may
be the same, or at least substantially the same, as a duration of each other
time interval in the
plurality of time intervals. IIowever, this is not required to all
implementations, and the
duration of one or more time interval in the plurality of time intervals may
differ from the
duration of one or more other time intervals in the plurality of time
intervals.
[0080] Calculating the frequency variation at 340 may include calculating
any suitable
frequency variation within each time interval and/or within each subset of the
plurality of
discrete frequency values. The calculating at 340 may be performed in any
suitable manner
and/or may calculate any suitable measure of variation, or frequency
variation. As an
example, the calculating at 340 may include calculating a statistical
parameter indicative of
variability within each subset of the plurality of discrete frequency values.
As another
example, the calculating at 340 may include calculating a frequency range
within each subset
of the plurality of discrete frequency values. As yet another example, the
calculating at 340
may include calculating a frequency standard deviation of, or within, each
subset of the
plurality of discrete frequency values. As another example, the calculating at
340 may include
scoring each subset of the plurality of discrete frequency values.
[0081] As yet another example, the calculating at 340 may include assessing
a margin, or
assessing the distinctiveness of a given frequency in a given time interval
relative to the other
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frequencies detected during the given time interval. This may include
utilizing a magnitude
and/or a probability density to assess the distinctiveness and/or utilizing a
difference between
a magnitude of a most common histogram element and a second most common
histogram
element within the given time interval to assess the distinctiveness.
[0082] As a more specific example, and when the calculating at 340 includes
calculating
the frequency range, the calculating at 340 may include binning, or
separating, each subset of
the plurality of discrete frequency values into bins. This is illustrated in
Fig. 13. Therein, a
number of times that a given frequency (i.e., represented by bins 1-14) is
observed within a
given time interval (i.e., represented by time intervals 1-10) is tabulated. A
zero value for a
given frequency bin-time interval combination indicates that the given
frequency bin was not
observed during the given time interval, while a non-zero number indicates the
number of
times that the given frequency bin was observed during the given time
interval.
[0083] Under these conditions, the calculating at 340 may include
determining a span, or
range, of the frequency bins. In the example of Fig. 13, the uppermost bin
that includes at
least one count is bin 14, while the lowermost bin that includes at least one
count is bin 11.
Thus, the span, or range, is 4, as indicated.
[0084] Selecting the subset of the plurality of time intervals at 350 may
include selecting
a subset within which the frequency variation, as determined during the
calculating at 340, is
less than a threshold frequency variation. Experimental data suggests that
time intervals
within which the frequency variation is less than the threshold frequency
variation represent
time intervals that are more representative of the major frequency of the
received acoustic
tone. As such, the selecting at 350 includes selectively determining which
time intervals are
more representative of, or more likely to include, the major frequency of the
received acoustic
tone, thereby decreasing noise in the overall determination of the major
frequency of the
received acoustic tone.
[0085] The selecting at 350 may include selecting a continuous range within
the tone
receipt time or selecting two or more ranges that are spaced-apart in time
within the tone
receipt time. Additionally or alternatively, the selecting at 350 may include
selecting at least
2, at least 3, at least 4, or at least 5 time intervals from the plurality of
time intervals.
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[0086] The selecting at 350 additionally or alternatively may
include selecting such that
the frequency variation within each successive subset of the plurality of
discrete frequency
values decreases relative to a prior subset of the plurality of discrete
frequency values and/or
remains unchanged relative to the prior subset of the plurality of discrete
frequency values.
[0087] An example of the selecting at 350 is illustrated in Fig.
13. In this example, time
intervals with a span of less than 10 are selected and highlighted in the
table. These include
time intervals 1, 4, and 5.
[0088] Averaging the plurality of discrete frequency values at 360
may include averaging
within the subset of the plurality of time intervals that was selected during
the selecting at 350
and/or averaging to determine the major frequency of the received acoustic
tone. The
averaging at 360 may be accomplished in any suitable manner. As an example,
the averaging
at 360 may include calculating a statistical parameter indicative of an
average of the plurality
of discrete frequency values within the subset of the plurality of time
intervals. As another
example, the averaging at 360 may include calculating a mean, median, or mode
value of the
plurality of discrete frequency values within the subset of the plurality of
time intervals.
[0089] As a more specific example, and with reference to Figs. 13-
14, the averaging at
360 may include summing the bins for the time intervals that were selected
during the
selecting at 350. As discussed, and utilizing one criteria for the selecting
at 350, bins 1, 4,
and 5 from Fig. 13 may be selected. The number of counts in these three bins
then may be
summed to arrive at Fig. 14, and the bin with the most counts, which
represents the most
common, or mode, frequency of the selected time intervals, may be selected. In
the example
of Fig. 14, this may include selecting bin 12, or the frequency of bin 12, as
the major frequency
of the received acoustic tone.
[0090] Transmitting the transmitted acoustic tone at 370 may
include transmitting with an
encoding node of the acoustic wireless network. The transmitting at 370 may be
subsequent,
or responsive, to the averaging at 360; and a transmitted frequency of the
transmitted acoustic
tone may be based, at least in part, on, or equal to, the major frequency of
the received acoustic
tone. Stated another way, the transmitting at 370 may include repeating, or
propagating, the
major frequency of the received acoustic tone along the length of the tone
transmission
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medium, such as to permit and/or facilitate communication along the length of
the tone
transmission medium.
[0091] Fig. 15 is a flowchart depicting methods 400, according to the
present disclosure,
of conserving power in an acoustic wireless network including a plurality of
nodes, while Fig.
16 is a schematic illustration of an example of the method of Fig. 15. As
illustrated in Fig.
15, methods 400 include repeatedly and sequentially cycling a given node at
410, transmitting
a transmitted acoustic tone at 420, receiving a received acoustic tone at 430,
and interrupting
the cycling for a threshold tone-receipt duration at 440. Methods 400 further
may include
remaining in an active state for the threshold tone-receipt duration at 450
and/or repeating at
least a portion of the methods at 460.
[0092] Methods 400 may be performed by an acoustic wireless network, such
as acoustic
wireless network 50 of Fig. 1. In such a network, at least one node 60 of the
plurality of
nodes 60 is programmed to perform the cycling at 410 and the receiving at 430,
and an
adjacent node 60 of the plurality of nodes is programmed to perform the
transmitting at 420.
[0093] Repeatedly and sequentially cycling the given node at 410 may
include cycling the
given node for a plurality of cycles. Each cycle in the plurality of cycles
includes entering,
for a low-power state duration, a low-power state in which the given node is
inactive, as
indicated at 412. Each cycle in the plurality of cycles further includes
subsequently
transitioning, for a listening state duration, to a listening state in which a
receiver of the given
node listens for a received acoustic tone from a tone transmission medium, as
indicated at
414.
[0094] In general, the low-power state duration is greater than the
listening state duration.
As examples, the low-power state duration may be at least 2, at least 3, at
least 4, at least 6, at
least 8, or at least 10 times greater than the listening state duration. As
such, the given node
may conserve power when compared to a node that might remain in the listening
state
indefinitely.
[0095] An example of the cycling at 410 is illustrated in Fig. 16, which
illustrates the state
of the given node as a function of time. As illustrated beginning on the
leftmost side of Fig.
16, the given node remains in a low-power state 480 for a low power state
duration 481 and
subsequently transitions to a listening state 482 for a listening state
duration 483. As also
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illustrated, the given node repeatedly cycles between the low-power state and
the listening
state. Each cycle defines a cycle duration 486, which is a sum of low-power
state duration
481 and listening state duration 483.
[0096] It is within the scope of the present disclosure that the given node
may have, or
include, an internal clock. The internal clock, when present, may have and/or
exhibit a low-
power clock rate when the given node is in the low-power state, a listening
clock rate when
the given node is in the listening state, and an active clock rate when the
given node is in the
active state. The low-power clock rate may be less than the listening clock
rate, thereby
permitting the given node to conserve power when in the low-power state. In
addition, the
listening clock rate may be less than the active clock rate, thereby
permitting the given node
to conserve power in the listening state when compared to the active state. It
is within the
scope of the present disclosure that the listening clock rate may be
sufficient to detect, or
detect the presence of, the received acoustic tone but insufficient to
resolve, or to determine a
frequency of, the received acoustic tone. In contrast, the active clock rate
may be sufficient
to resolve, or detect the frequency of, the received acoustic tone.
[0097] Transmitting the transmitted acoustic tone at 420 may include
transmitting during
the cycling at 410 and/or transmitting via the tone transmission medium. The
transmitting at
420 further may include transmitting for a tone transmission duration, and the
tone
transmission duration is greater than the low-power state duration of the
given node. As
examples, the tone transmission duration may be at least 110%, at least 120%,
at least 150%,
at least 200%, or at least 300% of the low-power state duration. Additionally
or alternatively,
the tone transmission duration may be at least as large as, or even greater
than, the cycle
duration. Examples of the tone transmission duration include durations of at
least 1
millisecond (ms), at least 2 ms, at least 4 ms, at least 6 ms, at least 8 ms,
or at least 10 ms.
[0098] The transmitting at 420 may be accomplished in any suitable manner.
As an
example, the transmitting at 420 may include transmitting with a transmitter
of another node
of the plurality of nodes. The other node of the plurality of nodes may be
different from and/or
spaced-apart from the given node of the plurality of nodes. Stated another
way, the tone
transmission medium may extend between, or spatially separate, the given node
and the other
node.
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[0099]
The transmitting at 420 is illustrated in Fig. 16. As illustrated therein, the
transmitter output may include a time period 490 in which there is no
transmitted acoustic
tone. In addition, the transmitter output also may include a time period 492
in which the
transmitter transmits the transmitted acoustic tone for a tone transmission
duration 493. Since
tone transmission duration 493 is greater than low-power state duration 481,
the given node
must be in listening state 482 for at least a portion of tone transmission
duration 493 regardless
of when transmission of the acoustic tone is initiated by the transmitter. As
such, the given
node cycles between low-power state 480 and listening state 482, thereby
conserving power,
while, at the same time, always being available to detect, or hear, the
transmitted acoustic
tone.
1001001 Receiving the received acoustic tone at 430 may include receiving
during the
listening state of a given cycle of the plurality of cycles and with the given
node. The receiving
at 430 further may include receiving from the tone transmission medium and/or
with the
receiver of the given node and may be subsequent, or responsive, to the
transmitting at 420.
[001011 Interrupting the cycling for the threshold tone-receipt duration at
440 may include
transitioning the given node to the active state for at least a threshold
active state duration and
may be subsequent, or responsive, to the receiving at 430. This is illustrated
in Fig. 16, with
the given node transitioning to an active state 484 and remaining in the
active state for a
threshold active state duration 485 responsive to the receiving at 430.
[00102] The threshold active state duration may be greater than the low-power
state
duration. As examples, the threshold active state duration may be at least
1.5, at least 2, at
least 2.5, at least 3, at least 4, or at least 5 times larger than the low-
power state duration, and
the interrupting at 440 may permit the given node to receive one or more
subsequent
transmitted acoustic tones in succession. As an example, the transmitted
acoustic tone may
be a first transmitted acoustic tone and the method may include transmitting a
plurality of
transmitted acoustic tones separated by a plurality of pauses, or time periods
490 in which no
acoustic tone is transmitted. Each pause may have a pause duration 494, and
the interrupting
at 440 may include remaining in the active state responsive to the pause
duration being less
than the threshold active state duration.
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[00103] Repeating at least the portion of the methods at 460 may include
repeating any
suitable portion of methods 400 in any suitable manner. As an example, and
responsive to
not receiving an acoustic tone for the threshold active state duration, the
repeating at 460 may
include returning to the cycling at 410, thereby conserving power while
permitting the given
node to detect a subsequent acoustic tone, which might be received from the
tone transmission
medium subsequent to the given node returning to the cycling at 410.
1001041 The acoustic wireless network and/or the nodes thereof, which are
disclosed
herein, including acoustic wireless network 50 and/or nodes 60 of Fig. 1, may
include and/or
be any suitable structure, device, and/or devices that may be adapted,
configured, designed,
constructed, and/or programmed to perform the functions discussed herein with
reference to
methods 200, 300, and/or 400. As examples, the acoustic wireless network
and/or the
associated nodes may include one or more of an electronic controller, a
dedicated controller,
a special-purpose controller, a special-purpose computer, a display device, a
logic device, a
memory device, and/or a memory device having computer-readable storage media.
[00105] The computer-readable storage media, when present, also may be
referred to
herein as non-transitory computer readable storage media. This non-transitory
computer
readable storage media may include, define, house, and/or store computer-
executable
instructions, programs, and/or code; and these computer-executable
instructions may direct
the acoustic wireless network and/or the nodes thereof to perform any suitable
portion, or
subset, of methods 200, 300, and/or 400. Examples of such non-transitory
computer-readable
storage media include CD-ROMs, disks, hard drives, flash memory, etc. As used
herein,
storage, or memory, devices and/or media having computer-executable
instructions, as well
as computer-implemented methods and other methods according to the present
disclosure, are
considered to be within the scope of subject matter deemed patentable in
accordance with
Section 101 of Title 35 of the United States Code.
[00106] In the
present disclosure, several of the illustrative, non-exclusive examples have
been discussed and/or presented in the context of flow diagrams, or flow
charts, in which the
methods are shown and described as a series of blocks, or steps. Unless
specifically set forth
in the accompanying description, it is within the scope of the present
disclosure that the order
of the blocks may vary from the illustrated order in the flow diagram,
including with two or
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more of the blocks (or steps) occurring in a different order and/or
concurrently. It is also
within the scope of the present disclosure that the blocks, or steps, may be
implemented as
logic, which also may be described as implementing the blocks, or steps, as
logics. In some
applications, the blocks, or steps, may represent expressions and/or actions
to be performed
by functionally equivalent circuits or other logic devices. The illustrated
blocks may, but are
not required to, represent executable instructions that cause a computer,
processor, and/or
other logic device to respond, to perform an action, to change states, to
generate an output or
display, and/or to make decisions.
[00107] As used herein, the term "and/or" placed between a first entity and a
second entity
means one of (1) the first entity, (2) the second entity, and (3) the first
entity and the second
entity. Multiple entities listed with "and/or" should be construed in the same
manner, i.e.,
"one or more" of the entities so conjoined. Other entities may optionally be
present other than
the entities specifically identified by the "and/or" clause, whether related
or unrelated to those
entities specifically identified. Thus, as a non-limiting example, a reference
to "A and/or B,"
when used in conjunction with open-ended language such as "comprising" may
refer, in one
embodiment, to A only (optionally including entities other than B); in another
embodiment,
to B only (optionally including entities other than A); in yet another
embodiment, to both A
and B (optionally including other entities). These entities may refer to
elements, actions,
structures, steps, operations, values, and the like.
[00108] As used
herein, the phrase "at least one," in reference to a list of one or more
entities should be understood to mean at least one entity selected from any
one or more of the
entity in the list of entities, but not necessarily including at least one of
each and every entity
specifically listed within the list of entities and not excluding any
combinations of entities in
the list of entities. This definition also allows that entities may optionally
be present other
than the entities specifically identified within the list of entities to which
the phrase "at least
one" refers, whether related or unrelated to those entities specifically
identified. Thus, as a
non-limiting example, "at least one of A and B" (or, equivalently, "at least
one of A or B," or,
equivalently "at least one of A and/or B") may refer, in one embodiment, to at
least one,
optionally including more than one, A, with no B present (and optionally
including entities
other than B); in another embodiment, to at least one, optionally including
more than one, B,
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with no A present (and optionally including entities other than A); in yet
another embodiment,
to at least one, optionally including more than one, A, and at least one,
optionally including
more than one, B (and optionally including other entities). In other words,
the phrases "at
least one," "one or more," and "and/or" are open-ended expressions that are
both conjunctive
and disjunctive in operation. For example, each of the expressions "at least
one of A, B and
C," "at least one of A, B, or C," "one or more of A, B, and C," "one or more
of A, B, or C"
and "A, B, and/or C" may mean A alone, B alone, C alone, A and B together, A
and C together,
B and C together, A, B and C together, and optionally any of the above in
combination with
at least one other entity.
[00109] In the
event that any patents, patent applications, or other references disclosed
herein (1) define a term in a manner that is inconsistent with and/or (2) are
otherwise
inconsistent with, either the present disclosure or any of the other disclosed
references, the
present disclosure shall control, and the term or disclosure therein shall
only control with
respect to the reference in which the term is defined and/or the disclosure
was present
originally.
1001101 As used herein the terms "adapted" and "configured" mean that the
element,
component, or other subject matter is designed and/or intended to perform a
given function.
Thus, the use of the terms "adapted" and "configured" should not be construed
to mean that a
given element, component, or other subject matter is simply "capable of'
performing a given
function but that the element, component, and/or other subject matter is
specifically selected,
created, implemented, utilized, programmed, and/or designed for the purpose of
performing
the function. It is also within the scope of the present disclosure that
elements, components,
and/or other recited subject matter that is recited as being adapted to
perform a particular
function may additionally or alternatively be described as being configured to
perform that
function, and vice versa.
1001111 As used herein, the phrase, "for example," the phrase, "as an
example," and/or
simply the term "example," when used with reference to one or more components,
features,
details, structures, embodiments, and/or methods according to the present
disclosure, are
intended to convey that the described component, feature, detail, structure,
embodiment,
and/or method is an illustrative, non-exclusive example of components,
features, details,
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structures, embodiments, and/or methods according to the present disclosure.
Thus, the
described component, feature, detail, structure, embodiment, and/or method is
not intended to
be limiting, required, or exclusive/exhaustive; and other components,
features, details,
structures, embodiments, and/or methods, including structurally and/or
functionally similar
and/or equivalent components, features, details, structures, embodiments,
and/or methods, are
also within the scope of the present disclosure.
Industrial Applicability
[00112] The wells and methods disclosed herein are applicable to the
acoustic wireless
communication, to the hydrocarbon exploration, and/or to the hydrocarbon
production
industries.
[00113] It is believed that the disclosure set forth above
encompasses multiple distinct
inventions with independent utility. While each of these inventions has been
disclosed in its
preferred form, the specific embodiments thereof as disclosed and illustrated
herein are not to
be considered in a limiting sense as numerous variations are possible. The
subject matter of
the inventions includes all novel and non-obvious combinations and
subcombinations of the
various elements, features, functions and/or properties disclosed herein.
Similarly, where the
claims recite "a" or "a first" element or the equivalent thereof, such claims
should be
understood to include incorporation of one or more such elements, neither
requiring nor
excluding two or more such elements.
[00114] It is believed that the following claims particularly point out
certain combinations
and subcombinations that are directed to one of the disclosed inventions and
are novel and
non-obvious. Inventions embodied in other combinations and subcombinations of
features,
functions, elements and/or properties may be claimed through amendment of the
present
claims or presentation of new claims in this or a related application. Such
amended or new
claims, whether they are directed to a different invention or directed to the
same invention,
whether different, broader, narrower, or equal in scope to the original
claims, are also regarded
as included within the subject matter of the inventions of the present
disclosure.
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