Note: Descriptions are shown in the official language in which they were submitted.
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EVALUATING VVELLBORE TELEMETRY SYSTEMS
TECHNICAL FIELD
[0001] This disclosure relates to wellbore telemetry systems.
BACKGROUND
[0002] Wellbore telemetry systems are used to exchange, e.g., power,
command, communication signals (or combinations of them), between a system
(e.g.,
a computer system) at a surface of a wellbore and a downhole tool positioned
at a
remote location inside the wellbore. The signals are used to perform
operations
including, e.g., powering the operation of the downhole tool and communicating
information, e.g., collected by the tool, between locations downhole and the
surface.
The wellbore telemetry systems can be implemented, e.g., as a wired drill pipe
wellbore telemetry system, an electromagnetic wellbore telemetry system, an
acoustic
wellbore telemetry system, or a wellbore telemetry system that includes
transceivers
coupled to sensors to transmit the signals.
[0003] In wired drill pipe telemetry systems, drill pipes that form a drill
string
are provided with electronics capable of passing the signals between the
computer
system at the surface and the downhole tool. To do so, such systems can
include
wires that form a communication chain that extends through the drill string.
Repeaters (or signal repeaters) can be disposed at selected positions along
the length
of the wires. Each repeater is adapted to receive and retransmit signals
communicated
in either direction along the drill string, e.g., to provide sufficient signal
amplitude at
the downhole tool. A quality of the wellbore telemetry system can be affected
by a
quality of the repeaters implemented in the system.
DESCRIPTION OF DRAWINGS
[0004] FIG. 1. illustrates an example wellbore telemetry system that includes
addressable components.
[0005] FIG. 2 illustrates example communication signals exchanged by an
evaluation computer system and the addressable components.
[0006] FIG. 3 is a flowchart of an example process for evaluating an
addressable component.
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[0007] FIG. 4 is a flowchart of an example process for evaluating an
addressable component.
[0008] FIG. 5 illustrates another example communication exchange by an
evaluation computer system and addressable components.
[0009] FIG. 6 illustrates another example communication exchange by an
evaluation computer system and addressable components.
[0010] Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
[0011] This disclosure describes evaluating wellbore telemetry systems, e.g.,
telemetry systems that include addressable components. A wellbore telemetry
system
includes signal transmission components to transmit signals, e.g.,
electromagnetic,
optical, acoustic, pressure signals. Using the signal transmission components,
fluid
flow modulation components, and other similar components, the wellbore
telemetry
system communicates between the terranean surface and downhole locations in
the
wellbore , for example, to communicate measurements made by well logging
tools,
e.g., Measurement While Drilling (MWD) tool, a Logging While Drilling (LWD)
tool,
or other suitable tool, to the surface.
[0012] Certain wellbore telemetry systems, e.g., wired drill pipe telemetry
systems, can include multiple addressable components disposed in series in the
wellbore. The addressable components can receive, retransmit, and respond to
signals
communicated in either direction, i.e., uphole or downhole, in the wellbore.
Operation of the wellbore telemetry system can depend on the performance of
each
addressable component included in the system, and the system can fail to
operate or
operate impaired if one or more of the components in the system is impaired
(e.g., is
faulty or not operating as expected). Without information on which addressable
component in the system is impaired all the addressable components may need to
be
removed from the wellbore to make a repair.
[0013] This disclosure describes techniques to evaluate each addressable
component
included in a wellbore telemetry system, while the telemetry system is in the
wellbore, to identify an addressable component that is impaired. Early
identification
of an impaired addressable component or impaired connection between two
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addressable components before removing all the addressable components from the
wellbore can save rig time. For example, upon identifying an impaired
addressable
component or connection, the string of addressable components need be removed
from the wellbore only to the position of the impaired addressable component.
Furthermore, the various implementations described below also allow optimizing
the
wellbore telemetry system by alleviating transmission bottlenecks at the
addressable
components. The operator may configure the addressable components at their
optimal
performance configuration according to at least one criterion, e.g. power
consumption
levels and/or data rates, maximize data throughput by replacing faulty
components,
spacing communicating components more appropriately for the well design,
and/or
minimize the overall power consumption. When utilizing batteries for power
sources,
the operator may want to configure/operate the various implementations as to
reduce
the battery consumption of the at least one of the components meanwhile
maintaining
a data throughput requirement. In other implementations, the operator may want
to
extend the reach in measured depth for a specified number of components while
maintaining a minimum data throughput requirement. The various implementations
allow operators to receive information describing the downhole location of the
fault or
limitation in real time. Thus, these implementations afford the operator the
opportunity of correcting or adjusting the system early on when drilling or
tripping
into the well and thereby minimize non-productive time when in the wellbore.
For
identifying faulty addressable components, one may implement and/or utilize
the
various implementations described here in addition to or en lieu of Time
Domain
Reflectometry (TDR)
[0014] FIG. 1 illustrates an example wellbore telemetry system that includes
multiple addressable components, e.g., repeaters. A wellbore environment 100
includes a wellbore 102 in which a string 106, e.g., a drill string, is
suspended, e.g., by
a drilling rig 103. The string 106 can include multiple lengths of pipe
coupled end-to-
end (e.g., using threads or otherwise). The string 106 can include a tool 104
attached
to a lower end that is disposed within the wellbore 102. For example, the tool
104 can
be a bottom hole assembly, e.g., including a drill bit and other components
for
drilling, attached to an end of a drill string. The string 106 can include a
logging
instrument 108 near the tool 104. For example, the logging instrument 108 is a
MWD
tool and/or a IND tool that collects data (e.g., gamma, directional or
azimuthal data,
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resistivity data, and other suitable data) while the drilling tool drills
through
subsurface formations to extend the wellbore 102. The data describes, e.g., a
location
of the wellbore 102 and a subsurface formation that is being drilled to extend
the
wellbore 102.
[0015] A wellbore telemetry system 112 which includes multiple addressable
components, e.g., repeaters, connected in a series is disposed in the wellbore
102.
The addressable components include, e.g., a first addressable component 110a,
a
second addressable component 110b, a third addressable component 110c, and
additional addressable components (not shown). The wellbore telemetry system
112
includes multiple communication links that connect the multiple addressable
components. The wellbore telemetry system 112 can also include equipment mid-
string, e.g., sensors or other equipment operated by the wellbore telemetry
system
112. An addressable component receives data from a downhole addressable
component in the series via a communication link and transmits the data to an
uphole
addressable component in the series via another communication link, and vice
versa.
[0016] Each addressable component can comprise of a receiver and a
transmitter to receive and retransmit commands and/or data through the
communication links between neighboring addressable components. For receiving,
some addressable component implementations can comprise of any subset or
combination of the following: a sensor to receive modulated pressure within
the
drilling fluid (e.g. strain gauge, piezoelectric quartz), an acoustic sensor
for receiving
modulated acoustic communications (e.g. microphone), a photo-sensitive diode
receiving light of at least one frequency, and/or a first electrical contact
receiving a
modulated voltage potential applied from a remote location (e.g. tubular
housing &
ceramic spacer). For transmitting, any of the implementations can further
comprise of
any subset or combination of the following: a valve in contact with the
drilling fluid
modulating pressure within said fluid (e.g. rotor & stator), an acoustic
actuator for
creating acoustic communications (e.g. piezoelectric ceramic), a Light
Emitting Diode
(LED) emitting light (e.g. laser in contact with a fiber optic strand), and/or
a second
electrical contact applying a modulated voltage potential in contact with a
media
conducive to current propagation within (e.g. copperwire, rock formation with
water
within its pore space with a non-zero salinity). Additional implementations
can
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further comprise of at least one battery configured to power said receiver
and/or
transmitter.
[0017] In Measurement While Drilling (MWD), mud pulse, electromagnetic
or acoustic applications (or combinations of two or more of them), multiple
addressable components can mechanically fasten to multiple drill pipe
sections. The
mechanical fastening can comprise of a screw-type fastener on at least one end
"female" threaded as to receive a "male" threaded counterpart of a first
section of drill
pipe. Additional implementations can further comprise of a "male" threaded
counterpart as to insert into a "female" threaded counterpart of a second
section of
drill pipe. A preferred implementation can comprise of one "male" threaded end
and
one "female" threaded end configured to connect a first section of drill pipe
to a
second section of drill pipe in a serial fashion. Some system implementations
can use
a plurality of said addressable components. The one "male" and one "female"
thread
configuration can be a preferred implementation since drillpipe sections are
configured similarly, i.e. one "male" and one "female" as fasten in a serial
fashion
when lowered into the wellbore via rig derrick.
[0018] In Wireline applications, multiple addressable components can
mechanically fasten to multiple cabled sections. Without limitation, the
mechanical
fastener can also use similar forms of threaded "male/female" configurations.
Thus,
the Wireline system implementations can comprise of addressable components
connected in a serial fashion with at least one cabling connection between two
addressable components. Other implementations can comprise of multiple cabling
and addressable components connected in a serial fashion with the addressable
components communicating along the cabling components. In addition, each
addressable component can implement, e.g., as software, firmware, hardware (or
combinations of them), a data transmission protocol to receive and re-transmit
the
signals in either direction.
[0019] The wellbore telemetry system 112 is connected to a system 114
outside and at a terranean surface. In some implementations, the system 114 is
a
computer system, e.g., a desktop computer, a laptop computer, a server
computer, a
smartphone, a tablet computer, a personal digital assistant, or any other
suitable
computer. The system 114 includes a computer-readable medium 116 storing
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instructions executable by data processing apparatus 118 to perform signal
transmission and reception operations with the logging instrument 108.
[0020] The wellbore telemetry system 112 can implement tethered
communication devices, e.g., electrical cables, fiber optics, twisted pair, co-
axial
cables, or any other tethered communication device to transmit signals between
the
system 114 and the logging instrument 108. The system 114 can be a computer
system that transmits command signals to the wellbore telemetry system 112,
e.g., to
each addressable component, the logging instrument 108, the tool 104, or
combinations of them. The logging instrument 108 transmits collected data to
the
system 114 through the wellbore telemetry system 112. For example, the logging
tool
108 transmits the collected data uphole to the addressable component that is
nearest to
the logging tool 108, e.g., addressable component 110c. Addressable component
110c
receives the data and re-transmits the data uphole to the next serially
connected
addressable component, e.g., addressable component 110b. In this manner. the
addressable components serially receive and re-transmit the collected data
from the
logging instrument 108 to the system 114.
[0021] In some implementations, the system 114 includes an evaluation
computer system to evaluate the multiple, serially connected addressable
components
in the wellbore telemetry system 112. The evaluation computer system can
alternatively be implemented separately from the system 114 at the surface to
transmit
the multiple evaluation signals in a sequence downhole toward a device
disposed
downhole in the wellbore 102. The device can be, e.g., the logging instrument
108.
In some implementations, the evaluation computer system can be implemented in
any
one of the addressable components in the wellbore telemetry system 112. By
doing
so, one addressable component can be implemented to evaluate itself and other
addressable components in the wellbore telemetry system 112.
[0022] The evaluation computer system is configured to serially transmit
multiple evaluation signals to the multiple serially connected addressable
components.
Each addressable component is addressable by a respective one of the multiple
evaluation signals, described below with reference to FIG. 2, that the
evaluation
computer system transmits. In response to serially transmitting the multiple
evaluation signals, the evaluation computer system is configured to evaluate
the
multiple communication links to the multiple addressable components based on
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multiple responses to the multiple evaluation signals. By doing so, the system
114
can identify impaired or faulty addressable components in the wellbore
telemetry
system 112. Alternatively, the evaluation computer system can be implemented
downhole to transmit the multiple evaluation signals uphole from a device,
e.g., the
logging instrument 108, toward the system 114 at the surface of the wellbore
102. For
example, the evaluation computer system can be connected to or be included in
the
logging instrument 108.
[0023] The addressable components operate collectively to transmit data
collected by the logging instrument 108 in real time, i.e., without
substantial delay
after the logging instrument 108 obtains the data. An addressable component
can be
impaired or be faulty because of a faulty, e.g., broken, communication link
that
connects the addressable component to other addressable components or a faulty
wire,
cable or other communication device that connects the addressable component to
the
system 114 or to the logging instrument 108. The addressable component can be
impaired, e.g., due to random noise at a depth in the wellbore 102 at which
the
addressable component is positioned or due to temperature variations at the
addressable component's location (or combinations of them). Due to stochastic
aspects experienced by each addressable component, there is a probability of
error
associated with each addressable component. An impaired or faulty addressable
component can operate with the probability of error that is greater than an
acceptable
threshold probability caused by issues, e.g., battery loss, mechanical issues
(e.g.,
wear, shock), environmental reasons, or any issue that affects data
transmission in the
uphole or downhole directions. The evaluation computer system can implement
techniques to identify such an impaired or faulty addressable component as
well as
the addressable component's location in the wellbore 102.
[0024] FIG. 2 illustrates example communication signals exchanged by the
system 114 that includes the evaluation computer system and the addressable
components. At 202, the system 114 transmits a first evaluation signal, e.g.,
a
synchronize (SYN) packet, to a first addressable component 110a. At 204, the
first
addressable component 110a receives the first evaluation signal, and, at 206,
transmits
a response, e.g., a synchronize-acknowledge (SYN-ACK) packet, to the first
evaluation signal to the system 110a. The first evaluation signal can uniquely
address
the first addressable component 110a, and no other addressable components
receiving
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the signal will respond. Similarly, a response from the first addressable
component
110a can enable the evaluation computer system to determine that the response
is
from the first addressable component 110a.
[0025] Additional implementations of the evaluation signaling employed by
the evaluation computer can comprise of transmitting a variety of packet
sequences
encoded and modulated in multiple encoded signaling formats varying in data
rate
and/or power. An addressable component can comprise of a receiver for at least
one
of the encoded signaling formats; a transmitter for sending a confirmation
signal (e.g.
ACK or acknowledge, a confirmation of various diagnostic and/or configuration
information); and a processor enabled to conduct diagnostic calculations on
said
received signaling and encode a formatted response for signaling with said
transmitter. In some implementations, the evaluation signaling can comprise of
special commands within each encoded signaling format. These special commands
can comprise instructions for conducting connection diagnostics for at least
one data
rate with at least one other addressable component deeper in the wellbore.
[0026] In some implementations, the confirmation signal can comprise of
encoded diagnostic and/or configuration information (i.e. fastest received
data rate,
version number, received power level, etc.). The computer system can then wait
a
first specified duration threshold (i.e. a first time-out period) after
sending the
evaluation signal to a first addressable component before determining if the
first
addressable component is limited in configuration or in a fault state. In the
absence of
a received confirmation signal response from the first addressable component
prior to
an expiration of the first specified duration, the computer system can then
determine/conclude the first addressable component is in a state of fault or
the
communications with the first addressable component is limited or impaired. On
the
other hand, the computer system can receive a confirmation signal from the
first
addressable component within the first specified duration threshold.
[0027] In some implementations, the computer system and/or addressable
components can construct and transmit command instructions to then further
command a second (or at least one other) addressable component to transmit a
second
evaluation signal to a second addressable components. Some addressable
implementations can then transmit a second evaluation signal to a second
addressable
component and receive a second confirmation signal. For systems comprising of
two
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or more addressable components, the computer system can then wait a second
specified duration threshold before determining if a second addressable
component is
limited in configuration (or the effective channel between the computer system
and
the second addressable component restricts communications, or if the second
addressable component is in a fault state, etc.).
[0028] Thus, there are many implementations of the disclosure. For example,
the
concepts described here can be extended to three or more addressable
components as
described with reference to Fig. 5, which illustrates another example
communication
exchange by an evaluation computer system and addressable components. At 502,
the
system 114 transmits an evaluation signal to a first component 110a. At 504,
the first
component 110a receives an evaluation signal from a component that is
shallower in
the wellbore than the first component 110a. At 506, the first component 110a
transmits a confirmation signal to system 114, which the system 114 receives
at 508.
For example, the first component 110a transmits the confirmation signal within
a
specified duration failing which the system 114 determines that the first
component
110a is faulty or impaired.
[0029] At 510, the first component 110a transmits an evaluation signal to a
component deeper in the wellbore (e.g., the second component 110b). At 512,
the
second component 110b receives the evaluation signal from the first component
110a.
At 514, the second component 110b transmits a confirmation signal to the first
component 110a, which the first component 110b receives at 516. At 518, the
first
component 110b transmits a confirmation signal to the system 114 indicating
the
receipt of the confirmation signal from the second component 110b. For
example, the
second component 110b transmits the confirmation signal to the first component
110a
within the specified duration failing which the first component 110b does not
transmit
the confirmation signal to the system 114. In response to not receiving the
confirmation signal from the first component 110a, the system 114 determines
that the
second component 110b is faulty or impaired.
[0030] At 520, the second component 1106 transmits an evaluation signal to a
component deeper in the wellbore (e.g., the third component 110c), but
receives no
response to the evaluation signal. Because the second component 110b does not
receive a confirmation signal from the third component 110c, the second
component
1106 does not send a confirmation signal to the first component 110a, which,
in turn,
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does not send a confirmation signal to the system 114. After a specified
duration
expires (e.g., time out at 526), the system 114 determines a fault (or
impairment) at
the third component 110c at 528.
[00311 FIG 6 illustrates another example communication exchange by an
evaluation
computer system and addressable components. Similarly to Fig. 5, at 602, the
system
114 transmits an evaluation signal to a first component 110a. At 604, the
first
component 110a receives an evaluation signal from a component that is
shallower in
the wellbore than the first component 110a. At 606, the first component 110a
transmits a confirmation signal to system 114, which the system 114 receives
at 607.
For example, the first component 110a transmits the confirmation signal within
a
specified duration failing which the system 114 determines that the first
component
110a is faulty or impaired.
[0032] At 608, the first component 110a transmits an evaluation signal to a
component deeper in the wellbore (e.g., the second component ii Ob). At 610,
the
second component 1106 receives the evaluation signal from the first component
110a.
At 612, the second component 110b transmits a confirmation signal to the first
component 110a, which the first component 110b receives at 614. At 616, the
first
component 110b transmits a confirmation signal to the system 114 indicating
the
receipt of the confirmation signal from the second component 110b. For
example, the
second component 110b transmits the confirmation signal to the first component
110a
within the specified duration failing which the first component 110b does not
transmit
the confirmation signal to the system 114. In response to not receiving the
confirmation signal from the first component 110a, the system 114 determines
that the
second component ii Ob is faulty or impaired.
[0033] At 618, the second component 110b transmits an evaluation signal to a
component deeper in the wellbore (e.g., the third component 110c). At 620, the
third
component 110c receives an evaluation signal from the component shallower in
the
wellbore, e.g., the second component ii Ob. At 622, the third component 110c
transmits the confirmation signal to the second component 1106, which the
second
component 110b receives at 624. At 626, the second component 110b transmits a
confirmation signal to the first component 110a indicating a receipt of the
confirmation signal from the third component 110c. At 628, the first component
110a
receives the evaluation signal from the second component 110b. At 630, the
first
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component 110a transmits a confirmation signal to the system 114 indicating a
receipt
of the confirmation signal from the second component 110b. In response to
receiving
the confirmation signal, the system 114 detei ____________________ wines that
the third component 110c is
functioning as intended. In some
implementations, evaluation signals and
confirmation signals can be exchanged directly between the first component
110a and
the second component 11 Of), and between the second component 110b and the
third
component 110c. In some implementations, the evaluation signals and
confirmation
signals can be exchanged through intermediate addressable components between
the
first component 110a and the second component 110b, and between the second
component 110b and the third component 110c.
[0034] Thus, a system can comprise of three or more addressable components,
and
the computer system can further wait for three or more additional specified
duration
thresholds (see FIG. 5) before determining a fault condition. These
predetermine
duration thresholds can be proportional to the time needed to handshake a
round trip
to each corresponding addressable component, respectively.
[0035] The system 114 evaluates the communication link to the first
addressable component 110a based on the response. In some implementations
described below with reference to FIG 3, the evaluation computer system can
transmit the first evaluation signal multiple times to the first addressable
component
110a and evaluate the communication link based on a number of responses from
the
first addressable component 110a. For example, the evaluation computer system
can
implement the process 300 to evaluate the first addressable component 110a.
[0036] At 302, the evaluation computer system can transmit the first
evaluation signal to the addressable component 110a, and, at 304, check for a
response. At 306, the evaluation computer system can perform a check to
determine
if the first evaluation signal has been transmitted to the first addressable
component
110a a threshold number of times (e.g., 10 times). If the first evaluation
signal has not
been transmitted a threshold number of times (decision branch "NO" in FIG. 3),
then
the evaluation computer system can continue to transmit the first evaluation
signal to
the first addressable component 110a and check for a response. In this manner,
the
evaluation computer system can transmit the first evaluation signal multiple
times to
the first addressable component 110a.
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[0037] If the first addressable component 110a is operating without any fault,
then the first addressable component 110a would have responded to each
instance of
receiving a first evaluation signal from the evaluation computer system. At
308, the
evaluation computer system can detei mine a number of responses (e.g., 3 or
5 or 7) to
transmitting the first evaluation signal to the first addressable component
110a
multiple times (e.g., 10 times). At 310, the evaluation computer system can
determine
a ratio of a number of responses (e.g., 3 or 5 or 7) to a number of
transmissions (e.g.,
10). A response from the first addressable component 110a can be merely an
acknowledgement of receipt of the first evaluation signal. Alternatively or in
addition, the response can include data describing a status of the first
addressable
component 110a.
[0038] At 312, the evaluation computer system can perform a check to
determine if the determined ratio (e.g., 0.3 or 0.5 or 0.7) satisfies a
threshold ratio
(e.g., 0.6). If the threshold ratio is satisfied (decision branch "YES"), then
the
evaluation computer system can determine that the first addressable component
110a
is functioning properly (i.e., is not impaired and is without fault) at 314.
If the
threshold ratio is not satisfied (decision branch "NO"), then the evaluation
computer
system can determine that the first addressable component 110a is impaired or
is
faulty (or both) at 316. In some implementations, the evaluation computer
system
may not determine a ratio described above. Instead, the evaluation computer
system
can determine if a number of responses satisfied a threshold number of
responses. In
this manner, the evaluation computer system can determine if a communication
link to
the first addressable component 110 is performing optimally or has failed
based on a
number of responses to multiple transmissions of the first evaluation signal
to the first
addressable component 110a.
[0039] Returning to FIG 2, after receiving the response from the first
addressable component 110a, at 210, the computer system 114 transmits a second
evaluation signal to the second addressable component 110b. The second
addressable
component 110b is the next, successive addressable component in the series of
addressable components included in the wellbore telemetry system 112. The
evaluation computer system can evaluate the first addressable component 110a
(or
any addressable component or addressable components ahead of the second
addressable component 110b) while transmitting the second evaluation signal to
the
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second addressable component 110b. In other words, the transmission of
multiple
evaluation signals to multiple addressable components occurs in series, i.e.,
one
addressable component at a time. In addition, after an evaluation signal is
received
from an addressable component, a next evaluation signal is transmitted to a
successive
addressable component. However, evaluation of the addressable components based
on responses received from the addressable components can occur in parallel
with the
transmission of the evaluation signals. For example, after the evaluation
computer
system receives a response (or responses) from the first addressable component
110a,
the evaluation computer system can evaluate the first addressable component
110a
and transmit a second evaluation signal to the second addressable component
110b in
parallel.
[0040] The second addressable component 110b receives the second
evaluation signal at 212. At 214, the second addressable component 110b
transmits a
response to the second evaluation signal to the system 114. Similarly to the
first
evaluation signal, the second evaluation signal can uniquely address the
second
addressable component 110b. Also, a response from the second addressable
component 110b can enable the evaluation computer system to determine that the
response is from the second addressable component 1106.
[0041] The system 114 evaluates the communication link to the second
addressable component 110b based on the response. In some implementations
described below with reference to FIG. 4, the evaluation computer system can
transmit the second evaluation signal at a particular data rate to the second
addressable component 110b and evaluate the communication link based on
responses
from the second addressable component 110b. For example, the evaluation
computer
system can implement the process 400 to evaluate the second addressable
component
110b.
[0042] At 402, the evaluation computer system can transmit the second
evaluation signal to the second addressable component 110b at a data rate. At
404,
the evaluation computer system can perform a check for a response. If the
evaluation
computer system does not receive a response to the second evaluation signal at
the
data rate, then the evaluation computer system can determine that the second
addressable component 110b is impaired or is faulty. The evaluation computer
system
can expect a specific response to a specific message included in the second
evaluation
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signal. Not receiving a response can include failure to receive the specific
response.
In other words, even if the second addressable component 110b provided a
response
to the second evaluation signal, the evaluation computer system can
nevertheless
determine that the second addressable component 110b is impaired or is faulty
if the
response is not one that the evaluation computer system expected.
[0043] In response to determining that the second addressable component
110b is impaired or is faulty, at 406, the evaluation computer system can
decrease a
data rate of the second evaluation signal, e.g., from a first data rate to a
second data
rate that is less than the first data rate. The evaluation computer system can
transmit
the second evaluation signal at the decreased data rate to the second
addressable
component 110b and check for a response. The evaluation computer system can
continuously decrease the data rate of the second evaluation signal until the
second
addressable component 110b responds, e.g., a threshold number of times.
[0044] If the evaluation computer system receives a response, then the
evaluation computer system can conclude that the second addressable component
110b is operating without fault at a data rate at which the second addressable
component 110b responded to the second evaluation signal. In some
implementations, the evaluation computer system can transmit the second
evaluation
signal at the data rate multiple times to the second addressable component
110b. By
implementing techniques similar to those described above with reference to
FIG. 3,
the evaluation computer system can determine that a number of responses from
the
second addressable component 110h satisfies a threshold number of responses,
and,
accordingly, determine that the second addressable component 110b is operating
optimally.
[0045] Returning to FIG 2, after receiving the response from the second
addressable component 110b, at 218, the computer system 114 transmits a third
evaluation signal to the third addressable component 110c. The third
addressable
component 110c is the next, successive addressable component in the series of
addressable components included in the wellbore telemetry system 112. As
described
above, the evaluation computer system can evaluate the first addressable
component
110a or the second addressable component 110b (or any addressable component
ahead
of the third addressable component 110c) in parallel with transmitting the
third
evaluation signal to the third addressable component 110c. In some
implementations,
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to evaluate a communication link to the third addressable component 110c, the
evaluation communication system can detect an absence of a response to the
third
evaluation signal transmitted to the third addressable component 110c, and,
accordingly, at 220, determine that the third addressable component 110c is
faulty. In
some implementations similar to those described above, the evaluation computer
system can transmit the third evaluation signal multiple times to the third
addressable
component 110c, and determine that the third addressable component 110c is
faulty
upon detecting an absence of at least a threshold number of responses.
[0046] The evaluation computer system can be configured to implement the
example evaluation techniques described above with reference to one
addressable
component to evaluate any of the other addressable components. For example,
the
evaluation computer system can evaluate the first addressable component 110a
by
transmitting evaluation signals at different data rates, determine the second
addressable component 110b is faulty based on an absence of a response to the
second
evaluation signal, and evaluate the third addressable component 110a based on
a
number of responses to transmitting the third evaluation signal multiple
times. Also,
as described above, the transmission of evaluation signals to the multiple
addressable
components occurs serially, i.e., one addressable component at a time. But,
the
evaluation of the addressable components can occur in parallel with each other
and
with the transmission of the evaluation signals.
[0047] In some implementations, the evaluation computer system can serially
transmit the multiple evaluation signals to the multiple addressable
components. For
each addressable component, the evaluation computer system can continuously
decrease a data rate of an evaluation signal, as described above, to identify
a
respective data rate at which each addressable component operates optimally.
From
the multiple data rates identified for the serially connected multiple
addressable
components in the wellbore telemetry system 112, the evaluation computer
system
can determine the smallest data rate. The smallest data rate represents the
data rate at
which all addressable components in the wellbore telemetry system 112 operate
without fault. The system 114 can transmit through the multiple addressable
components at the smallest data rate, thereby causing all addressable
components to
operate without bottlenecks.
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[0048] As described above, an addressable component can include a battery to
receive and re-transmit signals. An addressable component's battery can
consume a
certain power to operate the addressable component at a particular data rate.
If the
addressable component is configured to operate at a data rate that is greater
than the
smallest data rate, then the addressable component's battery may be operable
at a
power that is lower than the certain power. The evaluation computer system can
determine that an addressable component, e.g., the addressable component
repeater
110b, is adapted to transmit data at a data rate that is greater than the
smallest data
rate at a first power. The system 114 can operate the second addressable
component
110b at a second power that is less than the first power, the second power
sufficient to
transmit data at the smallest data rate.
[0049] Implementations of the subject matter and the operations described in
this disclosure, e.g., the evaluation computer system, the system 114, an
addressable
component, (or combinations of them) can be implemented in digital electronic
circuitry, or in computer software, firmware, or hardware, including the
structures
disclosed in this disclosure and their structural equivalents, or in
combinations of one
or more of them. Implementations of the subject matter described in this
disclosure
can be implemented as one or more computer programs, i.e., one or more modules
of
computer program instructions, encoded on computer storage medium for
execution
by, or to control the operation of, data processing apparatus. Alternatively
or in
addition, the program instructions can be encoded on an artificially-generated
propagated signal, for example, a machine-generated electrical, optical, or
electromagnetic signal that is generated to encode information for
transmission to
suitable receiver apparatus for execution by a data processing apparatus.
[0050] A computer storage medium, for example, the computer-readable
medium, can be, or be included in, a computer-readable storage device, a
computer-
readable storage substrate, a random or serial access memory array or device,
or a
combination of one or more of them. Moreover, while a computer storage medium
is
not a propagated signal, a computer storage medium can be a source or
destination of
computer program instructions encoded in an artificially-generated propagated
signal.
The computer storage medium can also be, or be included in, one or more
separate
physical and/or non-transitory components or media (for example, multiple CDs,
disks, or other storage devices).
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[0051] The operations described in this disclosure can be implemented as
operations performed by a data processing apparatus on data stored on one or
more
computer-readable storage devices or received from other sources. The term
"data
processing apparatus" encompasses all kinds of apparatus, devices, and
machines for
processing data, including by way of example a programmable processor, a
computer,
a system on a chip, or multiple ones, or combinations, of the foregoing. The
apparatus can include special purpose logic circuitry, for example, an FPGA
(field
programmable gate array) or an ASIC (application-specific integrated circuit).
The
apparatus can also include, in addition to hardware, code that creates an
execution
environment for the computer program in question, for example, code that
constitutes
processor firmware, a protocol stack, a database management system, an
operating
system, a cross-platform runtime environment, a virtual machine, or a
combination of
one or more of them. The apparatus and execution environment can realize
various
different computing model infrastructures, such as web services, distributed
computing and grid computing infrastructures.
[0052] A number of implementations have been described. Nevertheless, it
will be understood that various modifications may be made without departing
from
the spirit and scope of the disclosure. Various implementation implementations
can
comprise of addressable components from any single or combination of the
following
(but not limited to) wellbore communication systems: mud pulse telemetry,
electromagnetic telemetry, acoustic telemetry, twisted pair and/or coaxial
cables,
wired pipe, and/or fiber optic. Additionally, any pair of addressable
components can
utilize multiple physical channel medias and/or comprise of multiple receivers
and
multiple transmitters. These multiple-input and multiple-output communication
implementation implementations can fiirther comprise of a multitude of
communication receivers and transmitters.
