CN105223623B - For the isolation circuit of low-field nuclear magnetic resonance apparatus - Google Patents
For the isolation circuit of low-field nuclear magnetic resonance apparatus Download PDFInfo
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- CN105223623B CN105223623B CN201510614340.8A CN201510614340A CN105223623B CN 105223623 B CN105223623 B CN 105223623B CN 201510614340 A CN201510614340 A CN 201510614340A CN 105223623 B CN105223623 B CN 105223623B
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Abstract
The embodiment of the present invention provides a kind of isolation circuit for low-field nuclear magnetic resonance apparatus.The circuit includes：First isolation circuit, the second isolation circuit and control circuit；First isolation circuit is connected between radiating circuit and antenna；Second isolation circuit is connected between antenna and receiving circuit；Second isolation circuit includes logical transition circuit, driving circuit, transformer-coupled circuit, switching circuit, the first MOSFET, the 2nd MOSFET and capacitance.The embodiment of the present invention is isolated radiating circuit and receiving circuit by the first isolation circuit and the second isolation circuit, and pass through the second isolation circuit connection antenna and receiving circuit, shorten the connection distance between antenna and receiving circuit, and second isolation circuit the amplitude of the reception signal of multiple frequency bands is not influenced, realize the isolation circuit suitable for low-field nuclear magnetic resonance apparatus, and isolation circuit bandwidth.
Description
Technical field
The present embodiments relate to petroleum exploration field more particularly to a kind of isolation electricity for low-field nuclear magnetic resonance apparatus
Road.
Background technology
Nuclear magnetic resonance log is a kind of new Logging Technology suitable for open hole well, is currently the only can directly measure arbitrarily
The logging method of lithology reservoir free fluid seepage flow bulk properties, there is apparent superiority.Nuclear magnetic resonance technique is to utilize original
The technology that the externally-applied magnetic field to interact between the paramagnetism and atomic nucleus of daughter nucleus is logged well.Low-field nuclear magnetic resonance apparatus is adopted
With same antenna transmitting RF pulse signal, receives echo-signal, which connects radiating circuit and receiving circuit, emits respectively
The voltage of antenna ends is very high during circuit transmission RF pulse signal, and RF pulse signal is caused to enter in receiving circuit；It receives
Circuit is in receives echo-signal, since the amplitude of echo-signal is smaller, the easy interference echo signal of noise of radiating circuit, and shadow
The reception of echo-signal is rung, radiating circuit and receiving circuit are isolated therefore, it is necessary to isolation circuit, make radiating circuit and is connect
Circuit is received not influence each other.
There are two types of forms for isolation circuit of the prior art：The first is quarter-wave transmission line and crossed diodes
With reference to mode realize isolation, i.e. antenna is connect with receiving circuit by transmission line, the length of simultaneous transmission line is equal to four/
One wavelength；Second of equivalent a quarter π real-time performance of use is isolated, i.e., antenna is passed with receiving circuit by equivalent a quarter
Defeated line connection.
The first isolation circuit causes isolation circuit not to be suitable for low-field nuclear magnetic resonance apparatus since transmission line is longer；The
Equivalent a quarter transmission line in two kinds of isolation circuits can cause amplitude fading to the reception signal of multiple frequency bands, cause equivalent
The frequency band of a quarter π networks is relatively narrow.
Invention content
The embodiment of the present invention provides a kind of isolation circuit for low-field nuclear magnetic resonance apparatus, is suitable for low field core to realize
The isolation circuit of magnetic resonance tool, and isolation circuit bandwidth.
The one side of the embodiment of the present invention is to provide a kind of isolation circuit for low-field nuclear magnetic resonance apparatus, including：
First isolation circuit, the second isolation circuit and control circuit；Wherein：
First isolation circuit is connected between radiating circuit and antenna, and first isolation circuit includes the first two level
Pipe and the second diode, first diode and the second diode reverse parallel connection；
Second isolation circuit is connected between the antenna and receiving circuit, and second isolation circuit includes logic
Conversion circuit, driving circuit, transformer-coupled circuit, switching circuit, the first MOSFET, the 2nd MOSFET and capacitance, wherein, institute
It states logical transition circuit, the driving circuit, the transformer-coupled circuit and the switching circuit to be sequentially connected, described first
The grid of MOSFET is connected with the grid of the 2nd MOSFET, and the source electrode of the first MOSFET is with the 2nd MOSFET's
Source electrode is connected, and the capacitance connection is described to open between the source electrode of the first MOSFET and the grid of the first MOSFET
Powered-down road is connected in parallel on the both ends of the capacitance, and the drain electrode of the first MOSFET is connect with the antenna, the 2nd MOSFET
Drain electrode connect with the receiving circuit；
The control circuit is connected with the logical transition circuit, for controlling the first MOSFET and described second
MOSFET on or off.
The other side of the embodiment of the present invention is to provide a kind of low-field nuclear magnetic resonance apparatus, including the isolation electricity
Road and radiating circuit, receiving circuit and antenna.
Isolation circuit provided in an embodiment of the present invention for low-field nuclear magnetic resonance apparatus passes through the first isolation circuit and
Radiating circuit and receiving circuit is isolated in two isolation circuits, and passes through the second isolation circuit connection antenna and receive electricity
Road relative to quarter-wave transmission line or equivalent a quarter transmission line connection antenna and receiving circuit, shortens antenna
Connection distance between receiving circuit, and the second isolation circuit does not influence the amplitude of the reception signal of multiple frequency bands, it is real
The isolation circuit suitable for low-field nuclear magnetic resonance apparatus, and isolation circuit bandwidth are showed.
Description of the drawings
Fig. 1 is the isolation circuit provided in an embodiment of the present invention for low-field nuclear magnetic resonance apparatus；
Fig. 2 is the oscillogram that the control signal that another embodiment of the present invention provides passes through logical transition circuit；
Fig. 3 is the structure chart of driving circuit that another embodiment of the present invention provides；
Fig. 4 is the structure chart of transformer-coupled circuit that another embodiment of the present invention provides；
Fig. 5 is the oscillogram of transmitting signal and control signal that another embodiment of the present invention provides.
Specific embodiment
Fig. 1 is the isolation circuit provided in an embodiment of the present invention for low-field nuclear magnetic resonance apparatus.Needle of the embodiment of the present invention
The mode combined to quarter-wave transmission line with crossed diodes is not suitable for low-field nuclear magnetic resonance apparatus and equivalent four
The frequency band of/mono- π networks is relatively narrow, provides the isolation circuit for low-field nuclear magnetic resonance apparatus, as shown in Figure 1, for low field
The isolation circuit of nuclear magnetic resonance apparatus include the first isolation circuit 2, the second isolation circuit 3 and control circuit 6, wherein, first every
It is connected between radiating circuit 1 and antenna 4 from circuit 2, the first isolation circuit 2 includes the first diode 21 and the second diode
22,22 reverse parallel connection of the first diode 21 and the second diode；Second isolation circuit 3 be connected to antenna 4 and receiving circuit 5 it
Between, the second isolation circuit 3 includes logical transition circuit 31, driving circuit 32, transformer-coupled circuit 33, switching circuit 34, the
One MOSFET 36, the 2nd MOSFET 37 and capacitance 35, wherein, volume conversion circuit 31, driving circuit 32, transformer-coupled circuit
33 and switching circuit 34 be sequentially connected, the grid of the first MOSFET 36 is connected with the grid of the 2nd MOSFET 37, first
The source electrode of MOSFET 36 is connected with the source electrode of the 2nd MOSFET 37, and capacitance 35 is connected to the source electrode and of the first MOSFET 36
Between the grid of one MOSFET 36, switching circuit 34 is connected in parallel on the both ends of capacitance 35, drain electrode and the antenna 4 of the first MOSFET 36
Connection, the drain electrode of the 2nd MOSFET 37 are connect with receiving circuit 5；Control circuit 6 is connected with logical transition circuit 31, for controlling
Make the first MOSFET 36 and 37 on or off of the 2nd MOSFET.
In embodiments of the present invention, radiating circuit 1 emits CPMG pulse signals, and CPMG pulse signals are by the first isolation electricity
The voltage that the first diode 21 is added in behind road 2 is more than the cut-in voltage of diode, the first diode 21 conducting i.e. the first isolation electricity
Road 2 is connected, and the internal resistance very little of the first isolation circuit 2, CPMG pulse signals are entirely applied on antenna 4 at this time, meanwhile, control electricity
Road 6 generates control signal, and control signal passes sequentially through a volume conversion circuit 31, driving circuit 32, transformer-coupled circuit 33 and controls
Switching circuit 34 disconnects, so that the voltage at 35 both ends of capacitance is 0, at this point, the first MOSFET 36 and the 2nd MOSFET 37 ends,
I.e. antenna 4 is not turned on receiving circuit 5, is prevented CPMG pulse signals from entering receiving circuit 5 and is damaged receiving circuit 5.
When receiving circuit 5 is from 4 receives echo-signal of antenna, since the amplitude of echo-signal is smaller, echo-signal is passed through
The voltage that the second diode 22 is added in after first isolation circuit 2 is less than the cut-in voltage of diode, and the cut-off of the second diode 22 is
First isolation circuit 2 can not be connected, meanwhile, control circuit 6 generates control signal, and control signal passes sequentially through a volume conversion circuit
31st, driving circuit 32, transformer-coupled circuit 33 control switching circuit 34 to be closed, so that the voltage at 35 both ends of capacitance is not 0, this
When, the first MOSFET 36 and the 2nd MOSFET 37 is connected, i.e., antenna 4 is connected with receiving circuit 5, and receiving circuit 5 connects from antenna 4
Echo-signal is received, avoiding the noise signal of the generation of radiating circuit 1 influences the reception of echo-signal, and echo-signal is prevented to enter
Radiating circuit 1.
In addition, the isolation circuit provided in an embodiment of the present invention for low-field nuclear magnetic resonance apparatus can be operated in 500kHz-
In the frequency range of 30MHz, wideband is realized.
The embodiment of the present invention carries out radiating circuit and receiving circuit by the first isolation circuit and the second isolation circuit
Isolation, and pass through the second isolation circuit connection antenna and receiving circuit, relative to quarter-wave transmission line or four points equivalent
One of transmission line connection antenna and receiving circuit, shorten the connection distance between antenna and receiving circuit, and the second isolation electricity
Road does not influence the amplitude of the reception signal of multiple frequency bands, realizes the isolation circuit suitable for low-field nuclear magnetic resonance apparatus,
And isolation circuit bandwidth.
Fig. 2 is the oscillogram that the control signal that another embodiment of the present invention provides passes through logical transition circuit；Fig. 3 is this hair
The structure chart of driving circuit that bright another embodiment provides；Fig. 4 is the transformer-coupled circuit that another embodiment of the present invention provides
Structure chart；Fig. 5 is the oscillogram of transmitting signal and control signal that another embodiment of the present invention provides.In above-described embodiment
On the basis of, the first isolation circuit 2 includes two diode assemblies, and each diode assembly includes first diode 21 and one
A second diode 22.
As shown in Fig. 2, the output control signal of control circuit 6, logical transition circuit 31 turn the rising edge for controlling signal 311
The first undersuing 313 is changed to, and the failing edge for controlling signal 311 is converted into the second undersuing 314.It is of the invention real
It applies logical transition circuit 31 in example to be specifically made of gate circuit and coupled capacitor, the combination of gate circuit and coupled capacitor can be with
It is any one mode of the prior art.
As shown in figure 3, driving circuit 32 is used to carry out first undersuing and second undersuing
Power amplification.Driving circuit 32 includes regulator circuit 322 and driving chip 323, and regulator circuit 322 and driving chip 323 are connected,
Regulator circuit 322 includes backward dioded and resistance, backward dioded and resistor coupled in parallel.
As shown in figure 4, transformer-coupled circuit 33 includes the first transformer T1 and the second transformer T2, the first transformer T1
Primary 332 to input all the way, secondary 333 of the first transformer T1 is two-way different name end, and the primary 337 of the second transformer T2 is
It inputs all the way, the secondary 338 of the second transformer T2 is different name end, the first transformer T1 and the second transformer T2 are mutually only all the way
It is vertical.
First undersuing 313 is inputted the primary 332 of the first transformer T1, two-way different name end difference by driving circuit 32
Export the first positive pulse signal 334 and the second positive pulse signal 335；Second undersuing 314 is input to by driving circuit 32
The primary 337 of second transformer T2, all the way different name end output third positive pulse signal 339.
In embodiments of the present invention, the second isolation circuit 3 includes two identical driving circuits 32, due to logical transition electricity
The rising edge for controlling signal 311 is converted to the first undersuing 313, and the failing edge for controlling signal 311 is converted by road 31
For the second undersuing 314, the first undersuing 313 and the second undersuing 314 be separately input to two it is identical
In driving circuit 32, after the amplification of overdrive circuit 32, the first undersuing 313 is input to the first transformer T1, and first
Transformer T1 exports the first positive pulse signal 334 and the second positive pulse signal 335, the second undersuing 314 are input to second
Transformer T2.Second transformer T2 output thirds positive pulse signal 339.
Switching circuit 34 disconnects when receiving the first positive pulse signal 334 and the second positive pulse signal 335, switching circuit 34
It is closed when receiving third positive pulse signal 339.
Switching circuit 34 disconnects when receiving the first positive pulse signal 334 and the second positive pulse signal 335, so that capacitance 35
The voltage at both ends is 0, at this point, the first MOSFET 36 and the 2nd MOSFET 37 ends, i.e., antenna 4 is not turned on receiving circuit 5,
It prevents CPMG pulse signals from entering receiving circuit 5 and damages receiving circuit 5.Switching circuit 34 receives third positive pulse signal
It is closed when 339, so that the voltage at 35 both ends of capacitance is not 0, at this point, the first MOSFET 36 and the 2nd MOSFET 37 is connected, i.e.,
Antenna 4 is connected with receiving circuit 5, and receiving circuit 5 avoids the noise letter of the generation of radiating circuit 1 from 4 receives echo-signal of antenna
The reception of echo-signal number is influenced, and echo-signal is prevented to enter radiating circuit 1.
The duration of the radiating circuit transmitting signal is identical with the duration of high level in the control signal.This
Transmitting signal in inventive embodiments is specially CPMG pulse signals, and the frequency of CPMG pulse signals is very big, a large amount of intensive height
Envelope that the CPMG pulse signals of frequency are formed rectangle 65 as shown in Figure 5, starts to emit CPMG pulse signals in radiating circuit 1
When, there is rising edge 61 in control signal, and rising edge 61 generates the first undersuing 313 after logical transition circuit 31, the
One undersuing 313 enters the first transformer T1 of transformer-coupled circuit 33 after 32 amplifying power of overdrive circuit, the
One transformer T1 exports the first positive pulse signal 334 and the second positive pulse signal 335, switching circuit 34 receive the first positive pulse
It is disconnected when signal 334 and the second positive pulse signal 335.In the duration t1 for emitting CPMG pulse signals in radiating circuit 1, control
Signal processed is in high level state 62, and switching circuit 34 is off, and the voltage at 35 both ends of capacitance is 0, the first MOSFET
36 end with the 2nd MOSFET 37.When radiating circuit 1 emits CPMG pulse signal ends, there is failing edge 63 in control signal,
Failing edge 63 generates the second undersuing 314 after logical transition circuit 31, and the second undersuing 314 is through electricity of overdriving
Into the second transformer T2, the second transformer T2 output third positive pulse letter of transformer-coupled circuit 33 after 32 amplifying power of road
Numbers 339, switching circuit 34 is closed when receiving third positive pulse signal 339, and the voltage at 35 both ends of capacitance is not 0, and first
MOSFET 36 is connected with the 2nd MOSFET 37, at this point, receiving circuit 5 is from 4 receives echo-signal of antenna, and receives echo-signal
Time for t2, control signal is in low level state 64, when radiating circuit 1 emits CPMG pulse signals again according to above-mentioned
Mode recycles execution.
The embodiment of the present invention is by controlling the capacitance two being connect with the grid and source electrode of the first MOSFET and the 2nd MOSFET
The voltage at end controls the first MOSFET and the 2nd MOSFET on or off, realizes to radiating circuit and receiving circuit progress
Isolation.
The embodiment of the present invention also provides a kind of low-field nuclear magnetic resonance apparatus, which includes above-mentioned implementation
Isolation circuit and radiating circuit, the receiving circuit and antenna for low-field nuclear magnetic resonance apparatus in example.In conclusion this
Inventive embodiments are isolated radiating circuit and receiving circuit by the first isolation circuit and the second isolation circuit, and pass through
Second isolation circuit connects antenna and receiving circuit, connects relative to quarter-wave transmission line or equivalent a quarter transmission line
Antenna and receiving circuit are connect, shortens the connection distance between antenna and receiving circuit, and the second isolation circuit is to multiple frequency bands
The amplitude of reception signal do not influence, realize the isolation circuit suitable for low-field nuclear magnetic resonance apparatus, and isolation circuit frequency
Bandwidth；By controlling the voltage at capacitance both ends that is connect with the grid and source electrode of the first MOSFET and the 2nd MOSFET, the is controlled
One MOSFET and the 2nd MOSFET on or off, realize and radiating circuit and receiving circuit are isolated.
In several embodiments provided by the present invention, it should be understood that disclosed device and method can pass through it
Its mode is realized.For example, the apparatus embodiments described above are merely exemplary, for example, the division of the unit, only
Only a kind of division of logic function can have other dividing mode in actual implementation, such as multiple units or component can be tied
It closes or is desirably integrated into another system or some features can be ignored or does not perform.Another point, it is shown or discussed
Mutual coupling, direct-coupling or communication connection can be the INDIRECT COUPLING or logical by some interfaces, device or unit
Letter connection can be electrical, machinery or other forms.
The unit illustrated as separating component may or may not be physically separate, be shown as unit
The component shown may or may not be physical unit, you can be located at a place or can also be distributed to multiple
In network element.Some or all of unit therein can be selected according to the actual needs to realize the mesh of this embodiment scheme
's.
In addition, each functional unit in each embodiment of the present invention can be integrated in a processing unit, it can also
That each unit is individually physically present, can also two or more units integrate in a unit.Above-mentioned integrated list
The form that hardware had both may be used in member is realized, can also be realized in the form of hardware adds SFU software functional unit.
The above-mentioned integrated unit realized in the form of SFU software functional unit, can be stored in one and computer-readable deposit
In storage media.Above-mentioned SFU software functional unit is stored in a storage medium, is used including some instructions so that a computer
It is each that equipment (can be personal computer, server or the network equipment etc.) or processor (processor) perform the present invention
The part steps of embodiment the method.And aforementioned storage medium includes：USB flash disk, mobile hard disk, read-only memory (Read-
Only Memory, ROM), random access memory (Random Access Memory, RAM), magnetic disc or CD etc. it is various
The medium of program code can be stored.
Those skilled in the art can be understood that, for convenience and simplicity of description, only with above-mentioned each function module
Division progress for example, in practical application, can be complete by different function modules by above-mentioned function distribution as needed
Into the internal structure of device being divided into different function modules, to complete all or part of function described above.On
The specific work process of the device of description is stated, the corresponding process in preceding method embodiment can be referred to, details are not described herein.
Finally it should be noted that：The above embodiments are only used to illustrate the technical solution of the present invention., rather than its limitations；To the greatest extent
Pipe is described in detail the present invention with reference to foregoing embodiments, it will be understood by those of ordinary skill in the art that：Its according to
Can so modify to the technical solution recorded in foregoing embodiments either to which part or all technical features into
Row equivalent replacement；And these modifications or replacement, various embodiments of the present invention technology that it does not separate the essence of the corresponding technical solution
The range of scheme.
Claims (6)
1. a kind of isolation circuit for low-field nuclear magnetic resonance apparatus, which is characterized in that including：First isolation circuit, second every
From circuit and control circuit；Wherein：
First isolation circuit is connected between radiating circuit and antenna, first isolation circuit include the first diode and
Second diode, first diode and the second diode reverse parallel connection；
Second isolation circuit is connected between the antenna and receiving circuit, and second isolation circuit includes logical transition
Circuit, driving circuit, transformer-coupled circuit, switching circuit, the first MOSFET, the 2nd MOSFET and capacitance, wherein, it is described to patrol
It collects conversion circuit, the driving circuit, the transformer-coupled circuit and the switching circuit to be sequentially connected, described first
The grid of MOSFET is connected with the grid of the 2nd MOSFET, and the source electrode of the first MOSFET is with the 2nd MOSFET's
Source electrode is connected, and the capacitance connection is described to open between the source electrode of the first MOSFET and the grid of the first MOSFET
Powered-down road is connected in parallel on the both ends of the capacitance, and the drain electrode of the first MOSFET is connect with the antenna, the 2nd MOSFET
Drain electrode connect with the receiving circuit；
The control circuit is connected with the logical transition circuit, for controlling the first MOSFET and the 2nd MOSFET
On or off；
The transformer-coupled circuit includes the first transformer and the second transformer, and the primary of first transformer is defeated all the way
Enter, the secondary of first transformer is two-way different name end, and to input all the way, described second becomes the primary of second transformer
The secondary of depressor is different name end, first transformer and second transformer are mutual indepedent all the way；
The rising edge of the control signal is converted to first by the control circuit output control signal, the logical transition circuit
Undersuing, and the failing edge of the control signal is converted into the second undersuing；
First undersuing is inputted the primary of first transformer, the two-way different name end point by the driving circuit
The first positive pulse signal and the second positive pulse signal are not exported；
Second undersuing is inputted the primary of second transformer by the driving circuit, and the end of different name all the way is defeated
Go out third positive pulse signal；
The switching circuit disconnects when receiving first positive pulse signal and second positive pulse signal, the switch electricity
Road is closed when receiving the third positive pulse signal.
2. the isolation circuit according to claim 1 for low-field nuclear magnetic resonance apparatus, which is characterized in that described first every
Include two diode assemblies from circuit, each diode assembly includes first diode and one the described 2nd 2
Grade pipe.
3. the isolation circuit according to claim 1 for low-field nuclear magnetic resonance apparatus, which is characterized in that the driving electricity
Road is used to carry out power amplification to first undersuing and second undersuing.
4. the isolation circuit according to claim 3 for low-field nuclear magnetic resonance apparatus, which is characterized in that the driving electricity
Road includes regulator circuit and driving chip, and the regulator circuit and driving chip series connection, the regulator circuit include reversed
Diode and resistance, the backward dioded and the resistor coupled in parallel.
5. the isolation circuit according to claim 1 for low-field nuclear magnetic resonance apparatus, which is characterized in that the transmitting electricity
The duration of road transmitting signal is identical with the duration of high level in the control signal.
6. a kind of low-field nuclear magnetic resonance apparatus, which is characterized in that including such as claim 1-5 any one of them isolation circuit,
And radiating circuit, receiving circuit and antenna.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510614340.8A CN105223623B (en) | 2015-09-23 | 2015-09-23 | For the isolation circuit of low-field nuclear magnetic resonance apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510614340.8A CN105223623B (en) | 2015-09-23 | 2015-09-23 | For the isolation circuit of low-field nuclear magnetic resonance apparatus |
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| Publication Number | Publication Date |
|---|---|
| CN105223623A CN105223623A (en) | 2016-01-06 |
| CN105223623B true CN105223623B (en) | 2018-06-22 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201510614340.8A Active CN105223623B (en) | 2015-09-23 | 2015-09-23 | For the isolation circuit of low-field nuclear magnetic resonance apparatus |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5834936A (en) * | 1996-02-23 | 1998-11-10 | Western Atlas International, Inc. | Nuclear magnetic resonance apparatus and method |
| CN201178408Y (en) * | 2007-09-13 | 2009-01-07 | 上海维恩佳得数码科技有限公司 | Switch unit of MOS group switch and antenna transmitting circuit comprising the same |
-
2015
- 2015-09-23 CN CN201510614340.8A patent/CN105223623B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5834936A (en) * | 1996-02-23 | 1998-11-10 | Western Atlas International, Inc. | Nuclear magnetic resonance apparatus and method |
| CN201178408Y (en) * | 2007-09-13 | 2009-01-07 | 上海维恩佳得数码科技有限公司 | Switch unit of MOS group switch and antenna transmitting circuit comprising the same |
Non-Patent Citations (3)
| Title |
|---|
| "光电隔离抗干扰技术及应用";谢子青;《现代电子技术》;20031231(第13期);第33-37页 * |
| "基于FPGA的核磁共振测井仪控制逻辑设计";于慧俊 等;《波谱学杂志》;20120630;第29卷(第2期);第201-208页 * |
| "脉冲充放电方式控制MOS管实现隔离电路";杨光 等;《第十八届全国波谱学学术年会论文集》;20141010;第1-2页 * |
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| CN105223623A (en) | 2016-01-06 |
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