Patent ID: 12228029

DETAILED DESCRIPTION

Certain aspects and examples of the present disclosure relate to wireless transmission and reception of electrical signals to a device positioned downhole, for example but not limited to a sensor, via a TEC without a wired connection between the device and the TEC. A TEC may contain at least one electrical conductor within a metal tubing. The metal tubing may provide the at least one electrical conductor protection from abrasion and protection from fluids. The electrical conductor may carry power and data to downhole tools. Connecting a downhole tool to the TEC may, in some instances, require cutting the tubing, connecting the electrical conductor to the downhole tool, and wielding the tubing to the body of the downhole tool. Such a process can be expensive and time consuming. The present disclosure teaches methods and assemblies for transmitting data (i.e. transmission and/or reception of digital signals corresponding to commands or data) between a downhole device and a TEC and/or providing power to the downhole device from a TEC without hardwiring the downhole device to the TEC. Current may produce a magnetic field around a wire that is characteristic of the current within the wire. The magnetic field around the wire may provide power to the downhole device or may correspond to data being transmitted to the downhole device. Also, altering or producing a magnetic field around the wire may produce or influence the current within the wire. The magnetic field produced or altered around the wire may impart data via influencing the current in the wire.

Wireless transmission and reception of electrical signals between a downhole device and a TEC may improve wellbore systems' functioning by alleviating the need to physically hardwire the downhole device to the TEC which may cause damage to the TEC thus negatively impacting the functioning of the well system. Wireless transmission and reception of electrical signals along the TEC may also allow for finer control of production in the well system by using wired electronics, such as electronic inflow control valves (eICVs) to act as data hubs for wireless downhole devices. For example, elCVs, wired to the TEC, could receive electrical signals from nearby wireless sensors instead of the wireless sensors having to send signals to the surface, providing a short hop for communication between the wireless sensors and the EICV's electrical signal.

Transmitting and receiving electrical signals locally, via a network of wired and wireless downhole tools could also allow for a faster means of communication than transmitting every signal to the surface and receiving every signal from the surface via the TEC. The potential for increased speed in transmitting and receiving electrical signals may be explained by an increase in bandwidth that may be afforded by higher frequency signals sent and received locally. Higher frequency signals may be better suited for higher bandwidth applications than lower frequency signals, whereas lower frequency signals may be better suited to retaining coherence along a significant distance, such as a path from a down-well tool to the surface.

The electrical signals, received or transmitted wirelessly or with a wired connection to the TEC, may control any downhole device. For instance, data from a sensor wirelessly interfacing with the TEC could instruct a wired EICV to open, close, or adjust fluid flow through the EICV. In other examples a wireless downhole device may transmit via electrical signals commands to another downhole device or tool related to a hydrostatic system, setting a production packer, setting a sliding sleeve operable to provide a flowpath between an oilfield tubular and an annulus of a wellbore, or actuating a disconnect reel, or other command. Examples of oilfield tubulars include jointed pipe and coiled tubing.

The electrical signals may include data (including commands) that may be encoded in varying current amperage, voltage amplitude shifts, voltage phase shifts, voltage frequency shifts, timing shifts or other characteristics of alternating currents present within at least one alternating current within a TEC. Alternating current may be a time varying current where the frequency of the varying current is greater than 50 Hz. Data (including commands) may be encoded in varying current amperage of a direct current present within the TEC. Direct current may be a quasi-static current that may have a non-zero average current value. Data encoding may be achieved by varying voltage at a voltage source at the surface from which the TEC originates. The data encoded in the alternating current within a TEC may accompany an alternating current of a different frequency, used for power transmission. Also, the data encoded in the alternating current within a TEC may accompany a direct current used for power transmission.

Data encoded in alternating variable current within the TEC may be received as variations in a resulting magnetic field by a magnetic field sensor. In some examples, variations in the resulting magnetic field may be received by a magnetometer that measures magnetic field. In one example, the magnetometer is a transformer. The transformer may include but is not limited to a ferromagnetic ring that may surround the TEC such that the magnetic field created by the current within the TEC passes through the ferromagnetic ring. The transformer may also include a wire coil around the ferromagnetic ring that may transfer the magnetic flux passing through the ferromagnetic ring into electrical current representative of the data encoded in the current within the TEC. In some examples, the ferromagnetic ring may include ferrite though any suitable ferromagnetic material may be used. The term ferromagnetic is intended to include ferrimagnetic and paramagnetic behaviors. Additional examples of ferromagnetic materials include nickel-iron alloys such as Permalloy and mu-metal, iron, steel, and nickel.

Energy may be harvested from an alternating current within the TEC by a transformer. The transformer may include a ferromagnetic ring that may surround the TEC such that the magnetic field created by the current within the TEC passes through the ferromagnetic ring. The transformer may also include a wire coil around the ferromagnetic ring that may convert the magnetic flux passing through the ferromagnetic ring into electrical current that may be sufficient to power at least one downhole tool, sensor, control valve, or other device. The sensor may operate at a higher voltage and lower current than that of the TEC.

Illustrative examples are given to introduce the reader to the general subject matter discussed herein and are not intended to limit the scope of the disclosed concepts. The following sections describe various additional features and examples with reference to the drawings in which like numerals indicate like elements, and directional descriptions are used to describe the illustrative aspects, but, like the illustrative aspects, should not be used to limit the present disclosure.

FIG.1is a schematic diagram of a well system100including a wellbore extending through a subterranean formation, a casing string102extends within the wellbore according to one example of the present disclosure. A tubular104may extend within the casing string102. The well system100may also include a plurality of wireless devices110, which may be for example but not limited to sensors. A TEC106extends downhole and a plurality of wired devices108are hardwired to the TEC106. In some aspects, the TEC106may be positioned between an outer surface of the tubular104and the inner surface of the casing string102. As shown inFIG.1, in some aspects, the wireless devices110may each be wireless coupled to the TEC106via a transformer (shown as ferromagnetic rings112), for example for powering the wireless devices110via the TEC106. In some examples, the ferromagnetic rings112may include ferrite, though other suitable ferromagnetic materials may be used.

FIG.2is a portion of the schematic diagram of the well system100depicted inFIG.1including one of the wireless devices110and a transformer113, for receiving an electrical signal from the TEC106without hardwiring the wireless device110into the TEC106according to one example of the present disclosure. The transformer113as illustrated includes a ferromagnetic ring112encircling the TEC106, and a coil208of wire209wrapped around the ferromagnetic ring112. As an AC current, illustrated as ‘i,’ passes through an electrical conductor202within the TEC106, magnetic flux lines are concentrated in the ferromagnetic ring112. The coil208of wire209wraps around the ferromagnetic ring112and captures part of the magnetic field caused by the AC current thereby capturing some of the electrical energy from the TEC106. The coil208is also coupled to the wireless device110for transmitting power from the AC current flowing through the TEC106to the wireless device110for powering the wireless device110. The wireless device110may include a sensor that relays a measurement such as pressure, temperature, chemical composition, pH, water composition, or other characteristic. In some examples, the wireless device110may relay data related to the health or operational status of the wired device108which may in some examples be a downhole tool. A wired device108is electrically connected to the electrical conductor202within the TEC106. The wired device108may include an inflow control valve, a hydrostatic setting system, a control device for setting a packer, a control device for setting a sliding sleeve, an actuator for disconnecting a tool, or other downhole device.

The AC current within the electrical conductor202may be on top of a DC current flowing within the electrical conductor202. Data may be encoded in varying current amperage, voltage amplitude shifts, voltage phase shifts, voltage frequency shifts, timing shifts or other characteristics of the AC current. Data encoding may be achieved by varying voltage at a voltage source above a surface from which the TEC106originates. Data encoding may also be achieved by encoding an AC current created downhole by the wired device108. Examples of encoded data may include but are not limited to data corresponding to draw down rate flow rate, fluid viscosity, pressure, temperature, chemical composition, potential of hydrogen (pH) values, water composition, or operational status of the wired device108

The magnetic field212produced within the ferromagnetic ring112by the current200may possess a time-varying magnetic field values that parody the variations in the characteristics of the current200. The coil208may obtain an induced current from the magnetic field212produced within the ferromagnetic ring112. The induced current within the coil208may retain values that parody the variations within the current200and contain encoded data within the current200. The induced current may also be sufficient to power the wireless device110attached to the ferromagnetic ring112by the coil208.

The wired device108, may be able to serve as a data hub, capable of receiving data form the surface or transmitting data to the wireless device110. The wireless device110may be calibrated to accept electrical signals either associated with a particular channel or associated with a channel specific to the wireless device110. A turbine may be placed proximal to the wireless device110for the purpose of supplying energy to the wireless device110.

FIG.3is a schematic diagram of a portion of a well system including a voltage source318, a capacitor316, a ferromagnetic ring310, and a coil312of wire313for transmitting an electrical signal from the wireless device314uphole through the TEC302without hardwiring the wireless device314into the TEC302according to one example of the present disclosure. A current, illustrated as ‘i,’ may pass through an electrical conductor304within a TEC302. The TEC302originates from a surface. The ferromagnetic ring310encircles the TEC302. The ferromagnetic ring301is connected to the voltage source318by wire313that originates from the voltage source318, forms the coil312around the ferromagnetic ring310, and terminates back into the voltage source318. The combination of the ferromagnetic ring310and the coil312may constitute a transformer315. The coil312of the transformer315may be comprised of a plurality of windings of wire313, whereas the wire313may connect to the voltage source318directly. Other geometries of transformer, such as an autotransformer or a laminated core transformer, may replace the transformer315containing the ferromagnetic ring310and the coil312. The voltage source318is electrically connected to the capacitor316. The capacitor316is electrically connected to a wireless device314that is not hardwired to the TEC302. The wire. The wireless device314may include a sensor that relays a measurement such as pressure, temperature, chemical composition, pH, or water composition. The wireless device314may receive data related to the health or operational status of the wired device324. A wired device324is electrically connected to the electrical conductor304within the TEC302. The wired device324may include an inflow control valve, a hydrostatic setting system, a control device for setting a packer, a control device for setting a sliding sleeve, an actuator for disconnecting a tool, or a sensor that relays a measurement such as pressure, temperature, chemical composition, pH, or water composition.

The transformer315may create an AC magnetic flux that is concentrated in the ferromagnetic ring310. The AC magnetic field may create an AC current in the coil312. The transformer315may inject an AC electrical signal into the TEC302. The transformer315may create a short-duration AC current within the TEC302. A resulting AC current could be at a different frequency than a power frequency, which may be detected with greater fidelity uphole. The resulting AC current can even be an AC signal on a DC within the TEC302. Electrical energy could be collected in a capacitor bank to accumulate sufficient energy to amplify a signal of greater fidelity. The transformer315can use a time-varying magnetic field to induce an AC signal in the TEC302. The current within the electrical conductor304may include any combination of alternating currents or direct currents of varying phase or voltage amplitude. Data may be encoded in varying current amperage, voltage amplitude shifts, voltage phase shifts, voltage frequency shifts, timing shifts or other characteristics of alternating currents present within the current.

Data encoding may be achieved by varying voltage at a voltage source above the surface from which the TEC302originates. Examples of encoded data may include but are not limited to draw down rate flow rate, fluid viscosity, pressure, temperature, chemical composition, potential of hydrogen (pH) values, water composition, or operational status of the wired device324. The magnetic field320produced within the ferromagnetic ring310by the current may possess a time-varying magnetic field that parody the variations in the characteristics of the current.

The wireless device314may transmit an electrical signal to the voltage source318for amplification. The electrical signal may correspond to a command, a measurement, or other data. The voltage source318may use energy stored within the capacitor316to amplify the electrical signal across the wire313shaped into a coil312by providing a bias within the alternating current. An alternative means of energy storage, including but not limited to additional capacitors, at least one chemical battery, or any combination of devices suitable for storing electrical energy may be used in place of the capacitor316. A turbine may be placed proximal to the wireless device314for the purpose of supplying energy to the voltage source318or the wireless device314. The electrical signal transmitted through the coil312may alter the magnetic field320within the ferromagnetic ring310such that changes in the magnetic field320parody the electrical signal transmitted through the wire313. The alterations in the magnetic field320may alter characteristics of the electrical signal encoded in the AC current within the TEC302, thereby encoding the electrical signal originating from the wireless device314into the AC current. The AC current containing the electrical signal may be on top of a DC current flowing within the electrical conductor304within the TEC302. Wired electronics may be able to serve as a data hub, capable of receiving data from the surface or receiving data from the wireless device314. The wireless device314may be calibrated to transmit electrical signals either associated with a particular channel or associated with a channel specific to the wireless device314.

FIG.4is a schematic diagram of a portion of a wireless transmission assembly including a sensor coupled to a harvesting transformer428and a transmitting transformer426, the transformers being wirelessly coupled to a TEC according to one example of the present disclosure. The harvesting transformer428may power a wireless device414by harvesting AC power from the TEC. The transmitting transformer426may transmit data from the wireless device414by imparting an AC signal into the TEC. A current406, possessing an input voltage400, passes through an electrical conductor404within a TEC402. The TEC originates from a surface. As shown inFIG.4, the TEC may make a loop and return towards the surface. Alternatively, as shown inFIG.2, the TEC may be a single line without loops. A transmitting ring410encircles the TEC402. The transmitting ring410is disposed below a power harvesting transformer428, which also encircles the TEC402. The transmitting ring410is connected to a voltage source418by wire413that originates from the voltage source418, forms a transmitting coil412around the transmitting ring410, and terminates back into the voltage source418. The combination of the transmitting ring410and transmitting coil412may constitute a transmitting transformer426. The voltage source418is electrically connected to a capacitor416. The capacitor416is electrically connected to the wireless device414. The harvesting ring420is connected to the wireless device414by wire415that originates from the wireless device414, forms a harvesting coil422around the harvesting ring420, and terminates back into the wireless device414. The combination of the harvesting coil422and the harvesting ring420may constitute a harvesting transformer428. The harvesting transformer428may rectify the alternating current into a direct current that may be used by the wireless device414. In an alternative embodiment, the transmitting ring410and the harvesting ring420may be replaced by a single ferromagnetic ring, the single ferromagnetic ring being connected to both the transmitting coil412and the harvesting coil422. A wired device is electrically connected to the electrical conductor404within the TEC402.

The current406within the electrical conductor404may include any combination of alternating currents or direct currents of varying phase or voltage amplitude. A constant resistive load may be placed at either end of the TEC402. Data may be encoded in varying current amperage, voltage amplitude shifts, voltage phase shifts, voltage frequency shifts, timing shifts or other characteristics of alternating currents present within the current406. Data encoding may be achieved by varying voltage at a voltage source above the surface from which the TEC originates. Data encoding may also be achieved by changing current flow with the wired device424. Examples of encoded data may include but are not limited to draw down rate flow rate, fluid viscosity, pressure, temperature, chemical composition, potential of hydrogen (pH) values, water composition, or operational status of the wired device424. A magnetic field produced within the harvesting ring420by the current406may possess a time-varying magnetic field that parodies variations in the characteristics of the current406. The harvesting coil422may obtain an induced current from the magnetic field produced within the harvesting ring420. The induced current within the coil may retain values that parody variations within the current406and contain encoded data within the current406. The induced current obtained at the harvesting coil422may also be used to charge the capacitor416or another means of electrical energy storage, such as a capacitor bank, a chemical battery, a bank of chemical batteries, or a combination of batteries and capacitors.

The wireless device414may transmit an electrical signal to the voltage source418for amplification. The voltage source418may use energy stored within the capacitor416to amplify the electrical signal across the wire413shaped into the transmitting coil412. An alternative means of energy storage, including but not limited to additional capacitors, at least one chemical battery, or any combination of devices suitable for storing electrical energy may be used in place of the capacitor416. The electrical signal transmitted through the transmitting coil412may alter a magnetic field within the transmitting ring410such that changes in the magnetic field parody the electrical signal transmitted through the wire413shaped into the transmitting coil412. Alterations in the current406may affect an output voltage408.

Wired electronics, such as the wired device424may be able to serve as a data hub, capable of receiving data from the surface, receiving data from the wireless device414or similar sensors, transmitting data to the wireless device414or similar sensors, and routing data from the wireless device414or similar sensors to the surface. The wireless device414may be calibrated to transfer and/or receive electrical signals either associated with a particular channel or associated with a channel specific to the sensor414.

FIG.5is a schematic diagram of a portion of a wireless transmission assembly including a receiver wirelessly coupled to a TEC, for receiving electrical signals from the TEC502without hardwiring a wireless device into the TEC502, according to one example of the present disclosure. A current, illustrated as ‘i,’ may pass through an electrical conductor504within a TEC502. The TEC502originates from the surface512. The current within the electrical conductor504creates a magnetic field508around the TEC502. A magnetic field detector506is placed proximal to the TEC502such that the magnetic field508passes through the magnetic field detector506. A wired inflow control valve510is electrically connected to the electrical conductor504. within the TEC502. Electronics512are electrically connected to the magnetic field detector506and a downhole tool514. An energy storage device516is connected to the electronics512.

A constant resistive load may be placed at either end of the TEC502. Data may be encoded in varying current amperages of direct current present within the current. Data encoding may be achieved by varying voltage at a voltage source above the surface512from which the TEC502originates. Data encoding may also be achieved by changing current flow with the wired ICV510. Examples of encoded data may include but are not limited to commands to a device or tool downhole. For example, encoded data may correspond to a command to change a fluid restriction, to activate the downhole tool514, to release the downhole tool514, to adjust the programming of the downhole tool514. Encoded data may also include sensor data, for example but not limited to, data corresponding to a draw down rate flow rate, fluid viscosity, pressure, temperature, chemical composition, potential of hydrogen (pH) values, or water composition. The magnetic field508passing through the magnetic field detector506may possess a time-varying magnetic field that parodies the variations in the current. The magnetic field detector may interpret the time-varying magnetic field to derive the data encoded in the current. The sensor506can detect a DC current flowing through the TEC, so the data may be encoded with changes in the level of the DC current flow. Examples of magnetic field detector506include Hall effect sensors, magneto-resistive sensors such as giant magnetoresistive sensors (GMR), anisotropic magnetoresistive sensors (AMR), and tunnel magneto-resistive (TMR) sensors, and inductive coil sensors.

Wired electronics, such as the wired ICV510may be able to serve as a data hub, capable of receiving data from the surface512and routing the data to magnetic field sensors506downhole of the ICV510. The magnetic field sensor506may be calibrated to accept electrical signals either associated with a particular channel or associated with a channel specific to the magnetic field sensor506. The magnetic field sensor506may be in electrical communication with a downhole device powered by a turbine.

The electronics512may translate commands received by the magnetic field detector506from the TEC502. The electronics512may regulate an energy storage516, such as a chemical battery, so that the electronics512can relay commands to the downhole tool514. Commands may cause the downhole tool514to perform a wellbore function, such as setting a packer sleeve, dispensing cement, perforating a geological formation, or gathering a sample. Other wellbore functions are also possible in other examples.

FIG.6is a schematic diagram of a portion of a well system including a TEC with a wet connect, inflow control valves wired to an AC portion of the TEC, and electronic inflow control devices wirelessly coupled to a TEC according to one example of the present disclosure. The electronic inflow control devices are wirelessly coupled to the TEC to communicate with the inflow control valves via the TEC. A direct current flows along the TEC600, into a direct current to alternating current (DC-AC) transformer602. An alternating current flows from the DC-AC transformer602into a wet connect610. Downhole from the wet connect, the TEC600extends further downhole, connecting to inflow control valve (ICV) nodes608. Proximal to the portion of the TEC600downhole of the DC-AC transformer602are electronic inflow control device nodes606, which may be wirelessly linked to the TEC600via a transformer containing at least one ferromagnetic ring encompassing the TEC, or at least one magnetic field detector in range of a magnetic field produced by the TEC600.

The wet connect610may transfer electrical energy via magnetic induction or capacitive charging. The alternating current may optionally flow through a AC-DC transformer604. The DC-AC transformer602and the optional AC-DC transformer604may create both a direct current for powering wired ICV nodes608as well as an alternating current. Data may be encoded in varying current amperage, voltage amplitude shifts, voltage phase shifts, voltage frequency shifts, timing shifts or other characteristics of alternating currents present within the current200. Data may be encoded in varying current amperage of a direct current within the TEC. Data encoding may be achieved by varying voltage at a voltage source above a surface from which the TEC originates. Examples of encoded data may include but are not limited to draw down rate flow rate, fluid viscosity, pressure, temperature, chemical composition, potential of hydrogen (pH) values, water composition, or operational status of a wired device.

A magnetic field produced within a ferromagnetic ring or across a magnetic field detector of an electronic inflow control device node606may possess varying magnetic flux values that parody the variations in characteristics of the alternating current within the portion of the TEC600downhole of the DC-AC transformer602. The electronic inflow control device node606may interpret data encoded in the variations of characteristics of the alternating current. The electronic inflow control device nodes606or ICV nodes608may be calibrated to accept electrical signals either associated with a particular channel or associated with a channel specific to a given electronic inflow control device node606or ICV node608.

In some aspects, systems for wireless transmission and reception of electrical signals via tubing encased conductor are provided according to one or more of the following examples:

As used below, any reference to a series of examples is to be understood as a reference to each of those examples disjunctively (e.g., “Examples 1-4” is to be understood as “Examples 1, 2, 3, or 4”).

Example 1 is a system comprising: a tubing encased conductor (TEC); a transformer configured to inductively couple to the TEC; and a downhole device, coupled to the transformer, the downhole device comprising a transceiver configured to receive, from the transformer, digital signals encoded in a variable current in the TEC.

Example 2 is the system of example(s) 1, wherein the transceiver of the downhole device is further configured to transmit digital signals encoded in an alternating current to an at least one additional downhole device electrically coupled to the TEC.

Example 4 is the system of any of example(s) 1-2, further comprising a second transformer inductively coupled to the TEC, configured to transmit digital signals encoded in an alternating current of the TEC.

Example 4 is the system of any of example(s) 1-2, further comprising a wired downhole tool configured to couple to the TEC, the wired downhole tool configured to transmit digital signals corresponding to a command to the downhole device.

Example 5 is the system of any of example(s) 1-4, wherein digital signals encoded in an alternating current are encoded via variations in voltage, frequency, phase, or any other suitable parameter of the alternating current.

Example 6 is the system of any of example(s) 1-5, wherein the downhole device is configured to receive electrical power via the transformer.

Example 7 is the system of any of example(s) 1-6, wherein digital signals are encoded in an alternating current and are configured to traverse a direct current.

Example 8 is the system of any of example(s) 1-7, wherein digital signals transmitted by a wired downhole tool to the downhole device are of a higher frequency than digital signals originating from or directed to a processor at a surface.

Example 9 is the system of any of example(s) 1-8, further comprising: a direct current to alternating current transformer coupled above a wet-connect using an AC wet connect, an alternating current to direct current transformer coupled below the wet-connect for providing a direct current power source for the downhole device wired to the TEC; and an alternating current source for communication with the downhole device.

Example 10 is a system comprising: a tubing encased conductor (TEC); a transformer configured to inductively couple to the TEC; and a downhole device, coupled to the transformer, the downhole device comprising a transceiver configured to transmit, from the transformer, digital signals encoded in a variable current in the TEC.

Example 11 is the system of example(s) 10, wherein the transceiver of the downhole device is further configured to receive data from an at least one additional downhole device electrically coupled to the transceiver.

Example 12 is the system of any of example(s) 10-11, further comprising a second transformer inductively coupled to the TEC, configured to receive digital signals encoded in an alternating current of the TEC.

Example 13 is the system of any of example(s) 10-12, further comprising a capacitor coupled to the downhole device, configured to supply energy for transmission of digital signals encoded in an alternating current of the TEC.

Example 14 is the system of any of example(s) 10-13, wherein the digital signals are encoded in an alternating current and are encoded via variations in voltage, frequency, phase, or any other suitable parameter of the alternating current.

Example 15 is the system of any of example(s) 10-14, wherein the downhole device is configured to receive electrical power via the transformer.

Example 16 is the system of any of example(s) 10-15, wherein digital signals are encoded in an alternating current and are configured to traverse a direct current.

Example 17 is the system of any of example(s) 10-16, wherein digital signals received by a wired downhole tool to the downhole device are of a higher frequency than digital signals originating from or directed to a processor at a surface.

Example 18 is the system of any of example(s) 10-17, further comprising: a direct current to alternating current transformer coupled above a wet-connect using an AC wet connect, and an alternating current to direct current transformer coupled to the wet-connect for providing a direct current power source for the downhole device wired to the TEC as well as providing an alternating current electrical signal in addition to the direct current for communication with the downhole device.

Example 19 is a system comprising: a tubing encased conductor (TEC) for transmitting a direct current; a wireless device positioned downhole comprising: a magnetic sensor for wirelessly receiving a digital signal encoded in the direct current of the TEC, for controlling the wireless device positionable downhole; and a wired downhole tool coupled to the TEC, the wired downhole tool configured to transmit the digital signal to the wireless device positionable downhole via the TEC.

Example 20 is the system of example(s) 19, wherein the digital signal is encoded in the direct current via varying current amperage of the direct current.

The foregoing description of certain examples, including illustrated examples, has been presented only for the purpose of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Numerous modifications, adaptations, and uses thereof will be apparent to those skilled in the art without departing from the scope of the disclosure.