Patent Publication Number: US-2023145921-A1

Title: Efficient Transmitter For Nuclear Magnetic Resonance Logging While Drilling

Description:
BACKGROUND 
     During hydrocarbon exploration and production, nuclear magnetic resonance (NMR) may be utilized to acquire data from a downhole environment. NMR logging measures an induced magnet moment of hydrogen nuclei (protons) contained within fluid-filled pore space of porous media such as reservoir rocks. Unlike conventional logging measurements (e.g., acoustic, density, neutron, and resistivity), which are dependent on mineralogy and respond to a rock matrix and fluid properties, NMR-logging measurements respond to a presence of hydrogen in pore fluids, such as water and hydrocarbons, for example. NMR effectively responds to a volume, a composition, a viscosity, and a distribution of the pore fluids. NMR logs provide information about the quantities of fluids present, the properties of these fluids, and sizes of the pores containing these fluids. 
     Downhole NMR sensors have a relatively small radial extent of the sensitivity area making NMR well logging tool data sensitive to lateral (radial) motion, especially when making T2-measurements while drilling. To reduce sensitivity of LWD NMR tool to lateral motion when conducting T2 measurements while drilling, a short RF pulse is needed to increase the radial extent of the sensitive volume. To reduce this sensitivity, a short and high-power excitation RF pulse may be used to increases the radial extent of the sensitive area. Standard implementations for generating RF pulses may result in insufficient efficiency. For example, the generation efficiency suffers due to energy losses associated with charging a tank capacitor and then dumping stored energy in the tank into a critical resistor when ending the pulse. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These drawings illustrate certain aspects of some examples of the present disclosure and should not be used to limit or define the disclosure. 
         FIG.  1    illustrates an NMR tool in a wireline configuration, in accordance with examples of the present disclosure. 
         FIG.  2    illustrates an NMR tool in a drilling configuration, in accordance with examples of the present disclosure. 
         FIG.  3 A  illustrates a close-up cutaway perspective view of the NMR tool, in accordance with examples of the present disclosure. 
         FIG.  3 B  illustrates an axial cross-sectional view of the NMR tool, in accordance with examples of the present disclosure. 
         FIG.  4    illustrates an NMR antenna circuit. 
         FIG.  5 A  illustrates an improved NMR antenna circuit. 
         FIG.  5 B  illustrates a time diagram for switches from previous NMR antenna circuit. 
         FIG.  6 A  illustrates another example of an improved NMR antenna circuit. 
         FIG.  6 B  illustrates a time diagram for switches from previous NMR antenna circuit. 
     
    
    
     DETAILED DESCRIPTION 
     This disclosure details a method and system to improve the efficiency of generating RF pulses. Generally, proposed are methods and systems for improving the efficiency while generating RF pulses. Improving efficiency may be achieved by implementing rather than damping energy stored in the antenna at the end of the RF pulse. The disclosure discussed below relates to the energy stored in a capacitor within an NMR antenna circuit and disconnecting it from the antenna to use it to generate the next pulse(s). For a low frequency short RF pulse, in practical implementation, the proposed pulse generation scheme may save power. 
       FIG.  1    illustrates an operating environment for an NMR tool  100 , in accordance with examples of the present disclosure. It should be noted that while  FIG.  1    generally depicts a land-based operation, those skilled in the art may recognize that the principles described herein are equally applicable to subsea operations that employ floating or sea-based platforms and rigs, without departing from the scope of the disclosure. 
     As illustrated, NMR tool  100  may be operatively coupled to a conveyance  106  (e.g., wireline, slickline, coiled tubing, pipe, downhole tractor, and/or the like) which may provide mechanical suspension, as well as electrical connectivity, for NMR tool  100 . It should be understood that the configuration of NMR tool  100  shown on  FIG.  1    is merely illustrative and other configurations of NMR tool  100  may be used with the present techniques. 
     A conveyance  106  and NMR tool  100  may extend within a casing string  108  to a desired depth within wellbore  110 . Conveyance  106 , which may comprise one or more electrical conductors, may exit a wellhead  112 , may pass around a pulley  114 , may engage an odometer  116 , and may be reeled onto a winch  118 , which may be employed to raise and lower NMR tool  100  in wellbore  110 . Signals recorded by NMR tool  100  may be stored on memory and then processed by a display and storage unit  120  after recovery of NMR tool  100  from wellbore  110 . Alternatively, signals recorded by NMR tool  100  may be transmitted to display and storage unit  120  by way of conveyance  106 . The display and storage unit  120  may process the signals, and the information contained therein may be displayed for an operator to observe and store for future processing and reference. Alternatively, the signals may be processed downhole prior to receipt by display and storage unit  120  or both downhole and at a surface  122 , for example. Display and storage unit  120  may also contain an apparatus for supplying control signals and power to NMR tool  100 . Casing string  108  may extend from Wellhead  112  at or above ground level to a selected depth within wellbore  110 . Casing string  108  may comprise a plurality of joints  130  or segments of casing string  108 , each joint  130  being connected to the adjacent segments by a collar  132 . There may be any number of layers in casing string  108 . For example, the layers may comprise a first casing  134  and a second casing  136 . 
       FIG.  1    also illustrates a pipe string  138 , which may be positioned inside of casing string  108  extending part of the distance down wellbore  110 . Pipe string  138  may be production tubing, tubing string, casing string, or other pipe disposed within casing string  108 . Pipe string  138  may comprise concentric pipes. It should be noted that concentric pipes may be connected by collars  132 . NMR tool  100  may be dimensioned so that it may be lowered into wellbore  110  through pipe string  138 , thus avoiding the difficulty and expense associated with pulling pipe string  138  out of wellbore  110 . In examples, cement  140  may be disposed on the outside of pipe string  138 . Cement  140  may further be disposed between pipe string  138  and casing string  108 . It should be noted that cement  140  may be disposed between any number of casings, for example between first casing  134  and second casing  136 . 
     In logging systems utilizing NMR tool  100 , a digital telemetry system may be employed, wherein an electrical circuit may be used to both supply power to NMR tool  100  and to transfer data between the display and storage unit  120  and NMR tool  100 . A DC voltage may be provided to NMR tool  100  by a power supply located above ground level, and data may be coupled to the DC power conductor by a baseband current pulse system. Alternatively, NMR tool  100  may be powered by batteries located within the downhole tool assembly, and/or the data provided by NMR tool  100  may be stored within the downhole tool assembly, rather than transmitted to the surface during logging. 
     In certain examples, operation and function of NMR tool  100  may be controlled at surface  122  by a computer or an information handling system  144 . As illustrated, information handling system  144  may be a component of display and storage unit  120 . Information handling system  144  may comprise any instrumentality or aggregate of instrumentalities operable to compute, estimate, classify, process, transmit, receive, retrieve, originate, switch, store, display, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, or other purposes. For example, information handling system  144  may be a personal computer, a network storage device, or any other suitable device and may vary in size, shape, performance, functionality, and price. Information handling system  144  may comprise a processing unit  146  (e.g., microprocessor, central processing unit, etc.) that may process EM log data by executing software or instructions obtained from a local non-transitory computer readable media  148  (e.g., optical disks, magnetic disks). Non-transitory computer readable media  148  may store software or instructions of the methods described herein. Non-transitory computer readable media  148  may comprise any instrumentality or aggregation of instrumentalities that may retain data and/or instructions for a period of time. Non-transitory computer readable media  148  may include, for example, storage media such as a direct access storage device (e.g., a hard disk drive or floppy disk drive), a sequential access storage device (e.g., a tape disk drive), compact disk, CD-ROM, DVD, RAM, ROM, electrically erasable programmable read-only memory (EEPROM), and/or flash memory; as well as communications media such wires, optical fibers, microwaves, radio waves, and other electromagnetic and/or optical carriers; and/or any combination of the foregoing. At Surface  122 , information handling system  144  may also comprise input device(s)  150  (e.g., keyboard, mouse, touchpad, etc.) and output device(s)  152  (e.g., monitor, printer, etc.). Input device(s)  150  and output device(s)  152  provide a user interface that enables an operator to interact with NMR tool  100  and/or software executed by processing unit  146 . For example, information handling system  144  may enable an operator to select analysis options, view collected log data, view analysis results, and/or perform other tasks. In examples, NMR tool  100  and information handling system  144  may be utilized to measure properties (e.g., NMR properties) in a downhole environment. 
       FIG.  2    illustrates an example of NMR tool  100  included in a drilling system  200 , in accordance with examples of the present disclosure. It should be noted that while  FIG.  2    generally depicts a land-based operation, those skilled in the art may recognize that the principles described herein are equally applicable to subsea operations that employ floating or sea-based platforms and rigs, without departing from the scope of the disclosure. 
     As illustrated, a borehole  204  may extend from a wellhead  202  into a subterranean formation  205  from a surface  207 . Borehole  204  may comprise horizontal, vertical, slanted, curved, and other types of borehole geometries and orientations. A drilling platform  206  may support a derrick  208  having a traveling block  210  for raising and lowering a drill string  212 . Drill string  212  may include, but is not limited to, drill pipe and coiled tubing, as generally known to those skilled in the art. A top drive or kelly  214  may support drill string  212  as it may be lowered through a rotary table  216 . 
     A drill bit  218  may be attached to the distal end of drill string  212  and may be driven either by a downhole motor and/or via rotation of drill string  212  from the surface  207 . Without limitation, drill bit  218  may comprise roller cone bits, PDC bits, natural diamond bits, any hole openers, reamers, coring bits, and the like. As drill bit  218  rotates, it may create and extend borehole  204  that penetrates subterranean formation  205 . A pump  220  may circulate drilling fluid through a feed pipe  222  to kelly  214 , downhole through the interior of drill string  212 , through orifices in drill bit  218 , back to surface  207  via an annulus  224  surrounding drill string  212 , and into a retention pit  226 . 
     Drill string  212  may begin at wellhead  202  and may traverse borehole  204 . Drill bit  218  may be attached to a distal end of drill string  212  and may be driven, for example, either by a downhole motor and/or via rotation of drill string  212  from surface  207 . Drill bit  218  may be a part of a bottom hole assembly  228  at a distal end of drill string  212 . Bottom hole assembly  228  may comprise NMR tool  100  via threaded connections, for example. As will be appreciated by those of ordinary skill in the art, bottom hole assembly  228  may be a measurement-while drilling (MWD) or logging-while-drilling (LWD) system. 
     Without limitation, NMR tool  100  may be connected to and/or controlled by information handling system  144 . Processing of information recorded may occur downhole and/or at surface  207 . Data being processed downhole may be transmitted to surface  207  to be recorded, observed, and/or further analyzed. Additionally, the data may be stored in memory of NMR tool  100  while NMR tool  100  is disposed downhole. 
     In some examples, wireless communication may be used to transmit information back and forth between information handling system  144  and NMR tool  100 . Information handling system  144  may transmit information to NMR tool  100  and may receive, as well as process information recorded by NMR tool  100 . In examples, while not illustrated, bottom hole assembly  228  may comprise one or more additional components, such as an analog-to-digital converter, filter and amplifier, among others, that may be used to process the measurements of NMR tool  100  before they may be transmitted to the surface  207 . Alternatively, raw measurements may be transmitted to the surface  207  from NMR tool  100 . 
     Any suitable technique may be used for transmitting signals from NMR tool  100  to the surface  207 , including, but not limited to, wired pipe telemetry, mud-pulse telemetry, acoustic telemetry, and electromagnetic telemetry. While not illustrated, bottom hole assembly  228  may comprise a telemetry subassembly that may transmit telemetry data to surface  207 . Without limitation, an electromagnetic source in the telemetry subassembly may be operable to generate pressure pulses in the drilling fluid that propagate along the fluid stream to the surface  207 . At the surface  207 , pressure transducers (not shown) may convert the pressure signal into electrical signals for a digitizer (not illustrated). The digitizer may supply a digital form of the telemetry signals to information handling system  144  via a communication link  230 , which may be a wired or wireless link. The telemetry data may be analyzed and processed by the information handling system  144 . 
       FIG.  3 A  illustrates a cutaway close-up view of NMR tool  100  in accordance with some examples of the present disclosure. NMR tool  100  is a non-limiting example and other suitable NMR tools may be utilized, as should be understood by one having skill in the art, with the benefit of this disclosure. NMR tool  100  may comprise a housing  300  that may be of a cylindrical or tubular shape that extends longitudinally from a first end  301  to a second end  302 . In certain examples, first end  301  and second end  302  may be threaded for connection to a drill string for example. Magnets  303  may be disposed within housing  300 . Magnets  303  may be of a tubular shape and may comprise samarium-cobalt magnets, for example. In some examples, magnets  303  may encompass a passage  304  that extends longitudinally through housing  300 . A passage  304  may receive a fluid  306  (e.g., a drilling fluid) flowing in a downhole direction, as illustrated. A magnetic field  308  is emitted from magnets  303  and surrounds or encompasses housing  300 . NMR tool  100  may receive the fluid  306  at a rate ranging from 200 gallons per minute to 1000 gallons per minute, in some examples. 
       FIG.  3 B  illustrates an axial cross-section of NMR tool  100 , in accordance with some examples of the present disclosure. NMR tool  100  may be disposed in a wellbore  310 . Passage  304  may extend through a center of NMR tool  100  and may pass the fluid  306  from first end  301  (e.g., an up-hole end) to second end  302  (e.g., a downhole end). NMR tool  100  may further comprise a coaxially coil or NMR antenna circuit  312  wound about NMR tool  100  or wound around an inner (e.g., interior of the NMR tool  100 ) or outer circumference (e.g., exterior of the NMR tool  100 ) of housing  300 . A diameter of investigation, D, that extends into a subterranean formation  311 , may range from 8 inches to 20 inches, for example. 
     A magnetic field gradient  314  decays away from NMR tool  100 , as illustrated. At a selected operating frequency, NMR antenna circuit  312  transmits radio frequency (RF) signal or field Bi to the formation, NMR antenna circuit  312  and a static magnetic field Bo generated by the magnets  303  defines a sensitive volume, in the form of a resonant shell  316  that may encompass NMR tool  100 . NMR antenna circuit  312  may also serve as a receiver or a separate receiving NMR antenna circuit  312  can be used to receive the NMR signal from the fluids in the sensitive volume generated by the RF signal. The resonant shell  316  may extend longitudinally and have a length, L, ranging from 2 inches (5 centimeters (cm)) to 12 inches (30 cm), for example. Alternatively, the resonant shell  316  may have a length that is less than 2 inches (5 cm) or greater than 12 inches (30 cm), in some examples. A depth, d, of investigation into the subterranean formation  311  may range from 2 inches (5 cm) to 12 inches (30 cm) in some examples. The resonant shell  316  may comprise a thickness ranging from 0.1 inches (10 millimeters (mm)) to 1 inch (25 mm), for example. 
     In certain examples, the resonant shell  316  is the only location in the subterranean formation  311  where measurements are taken with NMR tool  100  (e.g., via the NMR antenna circuit  312 ). Measurements are not made between NMR tool  100  and resonant shell  316 , and from resonant shell  316  to further into the subterranean formation  311 . In certain examples, NMR tool  100  may comprise a downhole computer or downhole information handling system  318  for controlling and operating NMR tool  100 . Downhole information handling system  318  may be disposed within housing  300  and may comprise components that may be similar to information handling system  144  as previously described, such as, for example, a microprocessor, a memory, or other suitable circuitry, for estimating, receiving, storing, and/or processing signals or data in a downhole environment. 
       FIG.  4    illustrates an electrical structure of NMR antenna circuit  312  as a transmitter and/or receiver of NMR tool  100  (e.g., referring to  FIG.  1   ). NMR antenna circuit  312  may comprise a power source  402  such as a battery located on NMR tool  100  or an AC/DC power supply located at the surface. Additionally, NMR antenna circuit  312  may comprise an electronic switch  404 , a source resistor  406 , an inductive coil  408 , and first capacitor  410 . Inductive coil  408  represents the intrinsic inductive properties of NMR antenna circuit  312 . NMR antenna circuit  312  may further comprise an energy dump  412 , a decoupler switch  414  and receiver  416 . Decoupler switch  414  may be a transmitter/receiver decoupling switch. Receiver  416  may comprise a low noise amplifier and other stages of receiving electronics known to one of ordinary skill in the art. Generating an RF signal for NMR antenna circuit  312  may be accomplished by alternating or pulsing power source  402  at a rate of twice per period of a desired RF signal frequency via electronic switch, thus connecting power source  402  to inductive coil  408 . However, power source  402  may be pulsed at different rates in order to generate an RF signal. The beginning of the pulse charges first capacitor  410  and is associated with losses in source resistor  406 . During the RF pulse, additional energy is lost through inductive coil  408 . This lost energy may be measured by quality factor Q. Such energy loss may be compensated by periodically connecting inductive coil  408  to power source  402  during the pulse via electronic switch  404 . To end the RF pulse, energy present in NMR antenna circuit  312  is removed using energy dump  412 . During the RF signal generation decoupler switch  414  may be open so the receiver  416  is disconnected from NMR antenna circuit  312 . During the NMR signal acquisition, the de-coupler switch connects receiver  416  to the rest NMR antenna circuit  312  so that an NMR signal may be acquired. 
       FIG.  5 A  illustrates another example of NMR antenna circuit  312 . Such an example of NMR antenna circuit  312  may minimizes losses associated with starting the RF pulse by initially charging capacitor  410  for every pulse of the pulse sequence and ending the RF pulse by minimizing losses in energy dump  412 . As illustrated in  FIG.  5 A , RF pulse generator tank  506  may comprise first capacitor  410 , and inductive coil  408 . First capacitor  410  and inductive coil  408  may be tuned to operate at a desired operating frequency. Tuning first capacitor  410  and inductive coil may be adjustable to operate at multiple frequencies.  FIG.  5 A  also illustrates NMR signal acquisition tank  508 , which may comprise second capacitor  504 , receiver  416 , and inductive coil  408 . Similarly, second capacitor  504  and inductive coil  408  may be adjustably tuned for a selected desired operating frequency to resonate a current at the desired operating frequency. Inductive coil  408  may be configured in both RF pulse generator tank  506  and NMR signal acquisition tank  508 . Additionally,  FIG.  5 A  illustrates power switch  502 , electronic switch  404 , and decoupler switch  414 . Information handling system  144  may be configured to open and close electronic switch  404 , power switch  502 , and decoupler switch  414  via an electrically wired or wireless implementation. Information handling system  144  may switch and control NMR antenna circuit  312  during and between generating an RF pulse with RF pulse generator tank  506  and receiving an NMR signal with NMR signal acquisition tank  508 . 
     At the beginning of RF pulse generation RF pulse generator tank  506  is engaged. Power source  402  may initially charge first capacitor  410  at the beginning of RF pulse generation and/or during NMR signal acquisition. During RF pulse generation, energy stored in first capacitor and power source  402  may resonate and energize inductive coil  408  to produce an RF pulse with an RF current in the inductive coil  408  at desired operating frequency. To end the RF pulse generation, first capacitor  410  may be disconnected from inductive coil  408 . Thus, current in RF pulse generator tank  506 , when oscillating current in inductive coil  408  is substantially zero as all the energy of RF pulse generator tank  506  is stored in first capacitor  410 . Stored energy may be reused in subsequent RF pulse generation. As an effect, no energy is transferred to energy dump  412  (e.g., referring to  FIG.  4   ) and no energy losses associated with the dump are present in NMR antenna circuit  312  of  FIG.  5 A . 
     Subsequent to RF pulse generation, NMR antenna tank  508  may be used to receive an NMR signal. This may be accomplished by opening power switch  502  and closing decoupler switch  414  to disconnect first capacitor  410  and connect second capacitor  504  to NMR antenna  312 . The capacitance of second capacitor  504  may be substantially the same as first capacitor  410 . Alternatively, the capacitance of first capacitor  410  and second capacitor  504  may be slightly different to account for different parasitic capacitance of the receiver and transmitter circuits. 
       FIG.  5 B  shows time diagram  510 ,  512 , and  514  for electronic switch  404 , power switch  502 , and decoupler switch  414  respectively. T1 represents operation of the NMR antenna circuit  312  during RF pulse generation while T2 represents operation of the circuit of NMR antenna circuit  312  during NMR signal acquisition. Each time diagram  510 ,  512 , and  514  provides whether switch  404 , power switch  502 , and decoupler switch  414  are open as a “0” or closed as a “1”. One of ordinary skill in the art will appreciate a closed gate allows for the flow of electricity, while an open gate prevents the flow of electricity. It may be observed that during T1 phase RF pulse generation power switch  502  remains closed and electronic switch  404  pulses power source  402  to generate the RF pulse in NMR antenna circuit  312 . While during T2 phase of NMR signal acquisition power switch  502  opens and decoupler switch  414  closes, engaging second capacitor  504  and allowing first capacitor  410  to retain charge during NMR signal acquisition. 
       FIG.  6 A  represents another example of an NMR antenna circuit  312 . In this example, charging switch  602  may allow for an electrical connection from power source  402  to charge first capacitor  410 . At the origin of RF pulse generation, energy is delivered via charging switch  602  from power source  402  to charge first capacitor  410 . However, during NMR signal acquisition or free oscillation (decay) of RF pulse, charging switch  602  is open, while power switch  502  is closed. Free oscillation is defined as when energy stored in the first capacitor  410  and inductive coil  408  is constant. As Q may depend on the conductive surroundings of the NMR antenna circuit  312 , operational condition monitoring is required for power source  402  to enable proper feed forward regulation of the high voltage power supply output. Thus, high frequency switching as the one provided using the switch  404  (e.g., referring to  FIG.  5 A ) is not needed in this example. Additionally, power switch  502  may be closed during RF pulse generation, and open during NMR signal acquisition. Thus, energy may be preserved in first capacitor  410 . During NMR signal acquisition of NMR antenna circuit  312  illustrated in  FIG.  6 A , a second capacitor  504  (e.g., referring to  FIG.  5 A ) may be implemented. Implementation of second capacitor  504  may rely on second capacitor  504  to resonate with inductive coil  408  as illustrated in  FIG.  5 A . 
     Alternatively, power switch  502  may remain closed during NMR signal acquisition. Thus, a second capacitor  504  may not be implemented and residual energy loss may incur at energy dump  412  (e.g., referring to  FIG.  4   ). Additionally, power switch  502  may be removed from NMR antenna  312 . Removing power switch  502  may prevent losses due to resistance of the closed power switch  502 . Additionally, removing power switch  502  may allow capacitor  410  to charge before RF pulse generation. 
     When implementing the example presented in  FIG.  6 A , a free oscillation mode may be considered. During RF pulse generation, the phase of the oscillations may drift as the surroundings change during logging operations. Therefore, a system frequency adjustment may be implemented. System frequency adjustments to avoid mismatch between the transmitter frequency and reference frequency used in a quadrature detection system of receiver  416 , which may be illustrated by opening and closing charging switch  602  and power switch  502  at varying times. 
       FIG.  6 B  shows time diagram  604  and  606  for charging switch  602  and power switch  502 . In this example, T 1  represents operation of NMR antenna circuit  312  while charging capacitor  410  before RF pulse generation. T 2  represents operation of NMR antenna circuit  312  for RF pulse generation during free oscillation. Each time diagram  604  and  606  provides whether charging switch  602  and power switch  502  are open as a “0” or closed as a “1”. One of ordinary skill in the art will appreciate a closed gate allows for the flow of electricity, while an open gate prevents the flow of electricity. It may be observed that during T 1  phase, power switch  502  opens and charging switch  602  closes. While during T 2  phase, power switch  502  may close and charging switch  602  opens. 
     Utilizing the systems and methods above may be beneficial to improve the efficiency of generating RF pulses. Additionally, the disclosed systems and methods are improvements over current technology. For example, NMR transmit/receive circuitry is implemented having a reconfigurable antenna tank. This may be accomplished with multiple switches and two capacitors inside the NMR transmit/receive circuitry to preserve unconsumed energy in the tank created during the RF pulse generation. The switches may disconnect one capacitor from the antenna tank at the end of the RF pulse and conserve the energy for the next RF pulse. Therefore, charging the capacitor every time the RF pulse is generated and dumping the unconsumed energy may be avoided. The systems and methods may comprise any of the various features disclosed herein, including one or more of the following statements. 
     Statement 1. A nuclear magnetic resonance (NMR) downhole tool may comprise a housing, a power source disposed within the housing or at surface and electrically connected to the housing, a Radio Frequency (RF) pulse generator tank electrically connected to the power source and disposed in the housing, a power switch electrically disposed within the RF pulse generator tank and disposed in the housing, and an NMR signal acquisition tank electrically connected to the RF pulse generator tank and disposed in the housing. 
     Statement 2. The NMR antenna circuit of statement 1, further comprising an electronic switch electronically connected in series between the power source and the RF pulse generator tank. 
     Statement 3. The NMR antenna circuit of statement 2, further comprising a decoupler switch disposed within the NMR signal acquisition tank. 
     Statement 4. The NMR antenna circuit of statement 3, further comprising an information handling system, wherein the information handling system is communicatively connected to the power switch, the electronic switch, and the decoupler switch, and configured to open and close the power switch, the electronic switch, and the decoupler switch. 
     Statement 5. The NMR antenna circuit of statement 4, wherein the information handling system is configured to generate a RF pulse from an inductive coil electrically connected to the RF pulse antenna tank with energy stored in the first capacitor or the power source. 
     Statement 6. The NMR antenna circuit of statement 5, wherein the information handling system is configured to close the power switch, pulse the electronic switch, and open the decoupler switch. 
     Statement 7. The NMR antenna circuit of statement 4, wherein the information handling system is configured to acquire an NMR signal from an inductive coil electrically connected to the NMR signal acquisition tank. 
     Statement 8. The NMR antenna circuit of statement 7, wherein the information handling system is configured to open the power switch and the electronic switch and close the decoupler switch. 
     Statement 9. The NMR antenna circuit of statements 1 or 2, wherein the RF pulse generator tank further comprises a first capacitor and an inductive coil electrically connected to the RF pulse generator tank and the NMR signal acquisition tank. 
     Statement 10. The NMR antenna circuit of statement 9, wherein the first capacitor and the inductive coil are tuned to operate at a preselected frequency. 
     Statement 11. The NMR antenna circuit of any preceding statements 1, 2 or 9, wherein the NMR signal acquisition tank further comprises a receiver, a second capacitor, and an inductive coil electrically connected to the RF pulse generator tank and the NMR signal acquisition tank. 
     Statement 12. The NMR antenna circuit of statement 11, wherein the second capacitor and the inductive coil are tuned to operate at a desired frequency. 
     Statement 13. A method may comprise disposing a nuclear magnetic resonance (NMR) downhole tool into a wellbore. The NMR downhole tool comprise a housing, a power source disposed within the housing or at surface and electrically connected to the housing, a Radio Frequency (RF) pulse generator tank electrically connected to the power source and disposed in the housing, a power switch electrically disposed within the RF pulse generator tank and disposed in the housing, and an NMR signal acquisition tank electrically connected to the RF pulse generator tank and disposed in the housing. The method may further comprise charging a first capacitor with the power source that is electrically connected to the first capacitor, generating a Radio Frequency (RF) pulse with the RF pulse generator tank that comprise the first capacitor and an inductive coil, disconnecting the first capacitor from the RF pulse generator tank using a power switch, storing energy from the inductive coil in the first capacitor, connecting the inductive coil to an NMR signal acquisition tank using a decoupler switch, and acquiring an NMR signal with the NMR signal acquisition tank. 
     Statement 14. The method of statement 13, further comprising energizing the inductive coil with energy stored in the first capacitor and the power source. 
     Statement 15. The method of statement 14, further comprising pulsing an electronic switch disposed between the power source and the RF pulse generator tank to energize the inductive coil. 
     Statement 16. The method of any preceding statements 13 or 14, further comprising opening a charging switch disposed within the RF pulse generator tank to disconnect the first capacitor from the RF pulse generator tank. 
     Statement 17. The method of any preceding statements 13, 14, or 16, further comprising closing a decoupler switch disposed within the NMR signal acquisition tank to connect the NMR signal acquisition tank to the inductive coil. 
     Statement 18. The method of any preceding statements 13, 14, 16, or 17, wherein the RF pulse generator tank further comprises a first capacitor. 
     Statement 19. The method of any preceding statements 13, 14, or 16-18, wherein the first capacitor and the inductive coil are tuned to operate at a desired frequency. 
     Statement 20. The method of any preceding statements 13, 14, or 16-19, wherein the NMR signal acquisition tank further comprises a receiver and a second capacitor, wherein the second capacitor and the inductive coil are tuned to operate at a desired frequency. 
     Accordingly, the systems and methods of the present disclosure allow for the efficient transmission of signals from a nuclear magnetic resonance logging tool in a downhole environment. The systems and methods may comprise any of the various features disclosed herein, including one or more of the following statements. 
     Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations may be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. The preceding description provides various examples of the systems and methods of use disclosed herein which may contain different method steps and alternative combinations of components. It should be understood that, although individual examples may be discussed herein, the present disclosure covers all combinations of the disclosed examples, including, without limitation, the different component combinations, method step combinations, and properties of the system. It should be understood that the compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions and methods can also “consist essentially of” or “consist of” the various components and steps. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the element that it introduces. 
     For the sake of brevity, only certain ranges are explicitly disclosed herein. However, ranges from any lower limit may be combined with any upper limit to recite a range not explicitly recited, as well as, ranges from any lower limit may be combined with any other lower limit to recite a range not explicitly recited, in the same way, ranges from any upper limit may be combined with any other upper limit to recite a range not explicitly recited. Additionally, whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range are specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values even if not explicitly recited. Thus, every point or individual value may serve as its own lower or upper limit combined with any other point or individual value or any other lower or upper limit, to recite a range not explicitly recited. 
     Therefore, the present examples are well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular examples disclosed above are illustrative only and may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Although individual examples are discussed, the disclosure covers all combinations of all of the examples. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. It is therefore evident that the particular illustrative examples disclosed above may be altered or modified and all such variations are considered within the scope and spirit of those examples. If there is any conflict in the usages of a word or term in this specification and one or more patent(s) or other documents that may be incorporated herein by reference, the definitions that are consistent with this specification should be adopted.