CN106059520B - The real-time anti-saturation device of amplifier and real-time anti-saturation method in water system are visited in magnetic resonance - Google Patents
The real-time anti-saturation device of amplifier and real-time anti-saturation method in water system are visited in magnetic resonance Download PDFInfo
- Publication number
- CN106059520B CN106059520B CN201610351813.4A CN201610351813A CN106059520B CN 106059520 B CN106059520 B CN 106059520B CN 201610351813 A CN201610351813 A CN 201610351813A CN 106059520 B CN106059520 B CN 106059520B
- Authority
- CN
- China
- Prior art keywords
- signal
- real
- amplification factor
- circuit
- saturation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G3/00—Gain control in amplifiers or frequency changers without distortion of the input signal
- H03G3/20—Automatic control
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F13/00—Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units
- G06F13/38—Information transfer, e.g. on bus
- G06F13/382—Information transfer, e.g. on bus using universal interface adapter
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/12—Analogue/digital converters
- H03M1/124—Sampling or signal conditioning arrangements specially adapted for A/D converters
- H03M1/1245—Details of sampling arrangements or methods
Abstract
The present invention relates to a kind of magnetic resonance to visit the real-time anti-saturation device of amplifier and real-time anti-saturation method in water system, it is by being to be connect by pre-amplification circuit through wideband bandwidth-limited circuit, narrow-band filtering circuit, second amplifying circuit, programmable amplifying circuit and ADC module with FPGA module, FPGA module is connect respectively with ROM module, RAM module, programmable amplifying circuit, SCI interfaces and network interface, and FPGA module connects and composes respectively through SCI interfaces and network interface with computer.Idea of the invention is that estimating the size of next sampled point by the value of preceding several sampled points, and then each sampled point best magnification is set, that is, the requirement for reaching small-signal amplification ensures amplifier unsaturation again；It is all to be automatically performed in real time that entire amplification factor, which adjusts process, improves underground water detection efficient；Due to the addition of the real-time anti-saturation device, even if under the serious complex environment of noise jamming can complete underground water detection, and authentic data is provided for later stage signal processing and data inversion.
Description
Technical field
The present invention relates to a kind of anti-saturation device of amplifying circuit and anti-saturation methods, especially a kind of to be applied to be total in magnetic
It shakes and visits the real-time anti-saturation device of amplifier and anti-saturation method in water system.
Background technology
Nuclear magnetic resonance underground water Detection Techniques are that current geophysics field being capable of directly and nondestructively Underground water
Method.After underground water is excited by alternating magnetic field, generate NMR signal, which generally receives volt (nV) grade, need through
It can be just detected after crossing thousands of or tens of thousands of times of amplifications；Meanwhile the signal is easily interfered by external environment electromagnetic noise.Due to not
It is different with the interference noise in region to be measured or even also different in same measured zone electromagnetic interference noise in different time periods.It passes
The amplifying device that the nuclear magnetic resonance of system visits water reception system only rule of thumb only sets a times magnification before system work
Number, and the sampling time under the work of each pulse square is 256ms, the as shown in Figure 4 during this period of time amplitude of local signal
Dynamic change is larger, can lead to the big region amplifier saturation of signal using same amplification factor, the small region of signal is difficult to reach
To the effect of amplification, especially by the big interference of spike noise equal strength, system can not work normally.Therefore, in order to prevent
Amplifier saturation can meet the amplification factor requirement of magnetic resonance signal again, design the reality that amplifier in water system is visited in a kind of magnetic resonance
When anti-saturation device and anti-saturation method be of great significance.
Invention content
The purpose of the present invention provides a kind of magnetic resonance and visits amplifier in water system aiming at above-mentioned the deficiencies in the prior art
Real-time anti-saturation device
It is a further object of the present invention to provide the realities that the real-time anti-saturation device of amplifier in water system is visited in a kind of magnetic resonance
When anti-saturation method；
The purpose of the present invention is what is be achieved through the following technical solutions：
The real-time anti-saturation device that amplifier in water system is visited in a kind of magnetic resonance be by by pre-amplification circuit 1 through broadband
Bandpass filter circuit 2 is connect with narrow-band filtering circuit 3, and narrow-band filtering circuit 3 connects through second amplifying circuit 4 and programmable amplifying circuit 5
Connect, programmable amplifying circuit 5 is connect through ADC module 6 with FPGA module 7, FPGA module 7 respectively with ROM module 8, RAM module 9, journey
Control amplifying circuit 5, SCI interfaces 10 and network interface 11 connect, and computer 12 is connect respectively with SCI interfaces 10 and network interface 11
It forms.
The real-time anti-saturation method of real-time anti-saturation device of amplifier in water system is visited in magnetic resonance, is included the following steps：
A, system initialization：Manual setting initialization amplification factor A, preset upper limit value VmaxWith preset lower limit value Vmin；
B, signal acquisition：Signal acquisition mainly includes FPGA module 7 and controls ADC module 6 that faint magnetic resonance signal is premenstrual
Amplifying circuit 1, wideband bandwidth-limited circuit 2, narrow-band filtering circuit 3, second amplifying circuit 4 and programmable amplifying circuit 5 is put to amplify
After be converted to digital signal；
C, signal prejudges：According to the continuity of signal it is found that signal cannot be mutated, therefore utilize preceding 3 samplings of signal
The value V of pointi-2、Vi-1、ViIt makes next i.e. by sampled signal Vi+1The assessment of size, Vi+1=Vi+ T*a,
T is the sampling period in formula,
ViAnd Vi+1The slope of point-to-point transmission is a=ai+1.5(ai-ai-1),
Vi-1And ViThe slope of point-to-point transmission is ai=(Vi-Vi-1)/T,
Vi-2And Vi-1The slope of point-to-point transmission is aI-1=(Vi-1-Vi-2)/T；
D, amplification factor is adjusted：Work as Vmin<Vi+1<VmaxWhen, amplification factor does not adjust, with last sampled value ViIt uses
Same amplification factor Ai, i.e. Ai+1=Ai, wherein, VminIt is preset lower limit value, VmaxIt is preset upper limit value；Work as Vi+1<VminOr Vi+1
>VmaxWhen, amplification factor A next timei+1=Vref*Ai/Vi+1, wherein, Vref=(Vmin+Vmax)/2；Since programmable amplifier is
Digital regulated, amplification factor is discontinuous, and for rejective amplifier saturation, the amplification factor A actually adjusted is no more than above-mentioned
The A that method calculatesi+1, but will be closest to Ai+1；
E, sampled value normalized：All signal sampling values need to do same amplification factor calculating, each
Amplification factor when sampled value divided by the sampled value, i.e. real signal value Vi'=Vi/Ai；
F, into the cycle of real-time anti-saturation control next time：Signal acquisition, signal judge, adjustment amplification factor, sample
It is worth normalized, until the sampling time terminates.
Advantageous effect：The basic thought of the present invention is to estimate the big of next sampled point by the value of preceding several sampled points
It is small, and then each sampled point best magnification is set, the requirement for reaching small-signal amplification in this way ensures amplifier again
It is unsaturated；It is all to be automatically performed in real time that entire amplification factor, which adjusts process, improves underground water detection efficient；Since this is anti-in real time
The addition of saturation device, even if under the serious complex environment of noise jamming, can complete the detection of underground water, be later stage signal
Processing and data inversion provide authentic data.
Description of the drawings
Fig. 1 is the real-time anti-saturation apparatus structure block diagram that amplifier in water system is visited in magnetic resonance
Fig. 2 is the real-time anti-saturation method flow diagram of real-time anti-saturation device that amplifier in water system is visited in magnetic resonance
Fig. 3 is the time-domain diagram of four sampled points of signal
Fig. 4 is the magnetic resonance signal time-domain diagram that pulsatile once square measures
1 pre-amplification circuit, 2 wideband bandwidth-limited circuits, 3 narrow-band filtering circuits, 4 second amplifying circuits, 5 programming amplifyings
Circuit, 6AD capture cards, 7FPGA modules, 8ROM modules, 9RAM modules, 10SCI interfaces, 11 network interfaces, 12 computers.
Specific embodiment
The present invention is described in further detail with reference to the accompanying drawings and examples：
As shown in Figure 1, the real-time anti-saturation device of amplifier in water system is visited in magnetic resonance, it is to be passed through by pre-amplification circuit 1
Wideband bandwidth-limited circuit 2 is connect with narrow-band filtering circuit 3, and narrow-band filtering circuit 3 is through second amplifying circuit 4 and programming amplifying electricity
Road 5 connects, and programmable amplifying circuit 5 is connect through ADC module 6 with FPGA module 7, FPGA module 7 respectively with programmable amplifying circuit 5,
ROM module 8, RAM module 7, SCI interfaces 10, network interface 11 connect, computer 12 respectively with SCI interfaces 10, network interface 11
It connects and composes.Signal to be collected through pre-amplification circuit, wideband bandwidth-limited circuit, narrow-band filtering circuit, second amplifying circuit,
Input of the programmable amplifying circuit as ADC module；FPGA module regulation and control ADC module carries out analog-to-digital conversion, and the value of acquisition is deposited
It stores up in RAM module, after a pulse square point has been surveyed, computer is uploaded to by network interface together, initial parameter is set
Put is to be communicated by computer by SCI interfaces with FPGA module completion；FPGA module also completes the function of anti-saturation control,
The size of next sampled point is estimated according to the value of preceding 3 sampled points, amplification factor tune is completed by programmable amplifying circuit in advance
Whole, specific regulation process is as follows.
The real-time anti-saturation method of real-time anti-saturation device of amplifier in water system is visited in magnetic resonance, is included the following steps：
A, system initialization：Manual setting initialization amplification factor A, preset upper limit value VmaxWith preset lower limit value Vmin；
B, signal acquisition：Signal acquisition mainly includes FPGA module 7 and controls ADC module 6 that faint magnetic resonance signal is premenstrual
Amplifying circuit 1, wideband bandwidth-limited circuit 2, narrow-band filtering circuit 3, second amplifying circuit 4 and programmable amplifying circuit 5 is put to amplify
After be converted to digital signal；
C, signal prejudges：As shown in figure 4, according to the continuity of signal it is found that signal cannot be mutated, therefore utilize signal
The value V of preceding 3 sampled pointsi-2、Vi-1、ViIt makes next i.e. by sampled signal Vi+1The assessment of size, Vi+1=Vi+ T*a,
Formula wherein T is the sampling period,
ViAnd Vi+1The slope of point-to-point transmission is a=ai+1.5(ai-ai-1),
Vi-1And ViThe slope of point-to-point transmission is ai=(Vi-Vi-1)/T,
Vi-2And Vi-1The slope of point-to-point transmission is aI-1=(Vi-1-Vi-2)/T；
D, amplification factor is adjusted：Work as Vmin<Vi+1<VmaxWhen, amplification factor does not adjust, with last sampled value ViIt uses
Same amplification factor Ai, i.e. Ai+1=Ai, wherein, VminIt is preset lower limit value, VmaxIt is preset upper limit value；Work as Vi+1<VminOr Vi+1
>VmaxWhen, amplification factor A next timei+1=Vref*Ai/Vi+1, wherein, Vref=(Vmin+Vmax)/2；Since programmable amplifier is
Digital regulated, amplification factor is discontinuous, for rejective amplifier saturation, the amplification factor A≤A actually adjustedi+1, but A will
Closest to Ai+1；
E, sampled value normalized：All signal sampling values need to do same amplification factor calculating, each
Amplification factor when sampled value divided by the sampled value, i.e. real signal value Vi'=Vi/Ai；
F, into the cycle of real-time anti-saturation control next time：Signal acquisition, signal judge, adjustment amplification factor, sample
It is worth normalized, until the sampling time terminates.
Embodiment
In Changchun Bei Hu wetland parks, using transmitting coil area 100m*100m, receiving coil area 100m*100m, add
With entering the nuclear magnetic resonance of anti-saturation device for test water system, the real-time anti-saturation that amplifier in water system is visited to magnetic resonance fills
It puts and the application of anti-saturation method illustrates.Water system sample frequency f=25kHz is visited in magnetic resonance, each pulse square measures
Time 256ms, sampling number 6400.
Specific implementation step is as follows：
A, system initialization：Manual setting initialization amplification factor A=32000, preset upper limit value VmaxIt=4V and sets in advance
Limit value Vmin=1V；
B, signal acquisition：Signal acquisition mainly includes FPGA module 7 and controls ADC module 6 that faint magnetic resonance signal is premenstrual
Amplifying circuit 1, wideband bandwidth-limited circuit 2, narrow-band filtering circuit 3, second amplifying circuit 4 and programmable amplifying circuit 5 is put to amplify
After be converted to digital signal；
C, signal prejudges：Utilize value 2.5V, 3V, 3.6V of preceding 3 sampled points of signal, T=1/f=1/25000=
0.04ms, ai=(Vi-Vi-1)/T=(3.6-3)/0.04=15, aI-1=(Vi-1-Vi-2)/T=(3-2.5)/0.04=12.5, a
=ai+1.5(ai-ai-1)=18.75 are made next i.e. by the assessment V of sampled signal sizei+1=Vi+ T*a=4.35V；
D, amplification factor is adjusted：4.35V>4V, i.e. Vi+1>Vmax, Vref=(Vmin+Vmax)/2=(4+1)/2=2.5V, Ai
=32000, amplification factor A next timei+1=Vref*Ai/Vi+1=2.5*32000/4.35=18390, actual setting Ai+1=
18000；
E, sampled value normalized：All signal sampling values need to do same amplification factor calculating, each
Amplification factor when sampled value divided by the sampled value, i.e. real signal value Vi'=Vi/Ai=3.6/32000=0.1125mV；
F, into the cycle of real-time anti-saturation control next time：Signal acquisition, signal judge, adjustment amplification factor, sample
It is worth normalized, until the sampling time terminates.
Overall data is analyzed, signal mainly between preset upper limit value and preset lower limit value, was both satisfied without amplifier
With and distorted signals situation, and reached the requirement of amplified signal, authentic data provided for the post-processing of signal and inverting.
Claims (1)
- It is through broadband by pre-amplification circuit (1) 1. the real-time anti-saturation device of amplifier in water system is visited in a kind of magnetic resonance Bandpass filter circuit (2) is connect with narrow-band filtering circuit (3), and narrow-band filtering circuit (3) is through second amplifying circuit (4) and programming amplifying Circuit (5) connects, and programmable amplifying circuit (5) connect through ADC module (6) with FPGA module (7), FPGA module (7) respectively with ROM Module (8), RAM module (9), programmable amplifying circuit (5), SCI interfaces (10) and network interface (11) connection, computer (12) point It is not connected and composed with SCI interfaces (10) and network interface (11)；It is characterized in that, magnetic resonance visit water system in amplifier real-time anti-saturation device real-time anti-saturation method, including with Lower step：A, system initialization：Manual setting initialization amplification factor A, preset upper limit value VmaxWith preset lower limit value Vmin；B, signal acquisition：Signal acquisition mainly includes FPGA module (7) control ADC module (6), and faint magnetic resonance signal is premenstrual Put amplifying circuit (1), wideband bandwidth-limited circuit (2), narrow-band filtering circuit (3), second amplifying circuit (4) and programming amplifying Digital signal is converted to after circuit (5) amplification；C, signal prejudges：According to the continuity of signal it is found that signal cannot be mutated, therefore utilize preceding 3 sampled points of signal Value Vi-2、Vi-1、ViIt makes next i.e. by sampled signal Vi+1Assessment, Vi+1=Vi+ T*a,T is the sampling period in formula,ViAnd Vi+1The slope of point-to-point transmission is a=ai+1.5(ai-ai-1),Vi-1And ViThe slope of point-to-point transmission is ai=(Vi-Vi-1)/T,Vi-2And Vi-1The slope of point-to-point transmission is ai-1=(Vi-1-Vi-2)/T；D, amplification factor is adjusted：Work as Vmin<Vi+1<VmaxWhen, amplification factor does not adjust, with last sampled value ViUsing same Amplification factor Ai, i.e. Ai+1=Ai, wherein, VminIt is preset lower limit value, VmaxIt is preset upper limit value；Work as Vi+1<VminOr Vi+1>Vmax When, amplification factor A next timei+1=Vref*Ai/Vi+1, wherein, Vref=(Vmin+Vmax)/2；Since programmable amplifier is number It adjusts, amplification factor is discontinuous, and for rejective amplifier saturation, the amplification factor actually adjusted is not more than above method meter The A of calculatingi+1, but will be closest to Ai+1；E, sampled value normalized：All signal sampling values need to do same amplification factor calculating, each is sampled Amplification factor when value divided by the sampled value, i.e. real signal value Vi'=Vi/Ai；F, into the cycle of real-time anti-saturation control next time：Signal acquisition, signal judge, adjustment amplification factor, sampled value are returned One change is handled, until the sampling time terminates.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610351813.4A CN106059520B (en) | 2016-05-25 | 2016-05-25 | The real-time anti-saturation device of amplifier and real-time anti-saturation method in water system are visited in magnetic resonance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610351813.4A CN106059520B (en) | 2016-05-25 | 2016-05-25 | The real-time anti-saturation device of amplifier and real-time anti-saturation method in water system are visited in magnetic resonance |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106059520A CN106059520A (en) | 2016-10-26 |
| CN106059520B true CN106059520B (en) | 2018-07-03 |
Family
ID=57174436
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610351813.4A Active CN106059520B (en) | 2016-05-25 | 2016-05-25 | The real-time anti-saturation device of amplifier and real-time anti-saturation method in water system are visited in magnetic resonance |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106059520B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108152768A (en) * | 2017-11-29 | 2018-06-12 | 华东师范大学 | A kind of NMR signal acquisition processing device |
| CN109633759B (en) * | 2018-12-12 | 2020-02-07 | 吉林大学 | Ground magnetic resonance signal rapid extraction device and method based on phase-locked amplification technology |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6177794B1 (en) * | 1997-05-13 | 2001-01-23 | The Regents Of The University Of California | Use of earth field spin echo NMR to search for liquid minerals |
| CN102253913A (en) * | 2011-05-30 | 2011-11-23 | 神州数码网络(北京)有限公司 | Device for carrying out state acquisition and output control on multi-board-card port |
| CN102262247A (en) * | 2011-04-28 | 2011-11-30 | 吉林大学 | Device and method for predicting water burst of tunnel |
| CN203069679U (en) * | 2013-01-24 | 2013-07-17 | 吉林大学 | Field environment assessment device for nuclear magnetic resonance water exploration instrument |
| CN103323860A (en) * | 2013-05-28 | 2013-09-25 | 中国电子科技集团公司第三十八研究所 | Navigation receiver anti-saturation device based on direct radio frequency sampling |
| CN104297807A (en) * | 2014-09-06 | 2015-01-21 | 吉林大学 | Magnetic resonance imaging device for underground disaster water source detection and detection and imaging method |
| CN204719240U (en) * | 2015-04-22 | 2015-10-21 | 吉林大学 | Nuclear magnetic resonance wide and narrow strip merges amplifier module |
-
2016
- 2016-05-25 CN CN201610351813.4A patent/CN106059520B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6177794B1 (en) * | 1997-05-13 | 2001-01-23 | The Regents Of The University Of California | Use of earth field spin echo NMR to search for liquid minerals |
| CN102262247A (en) * | 2011-04-28 | 2011-11-30 | 吉林大学 | Device and method for predicting water burst of tunnel |
| CN102253913A (en) * | 2011-05-30 | 2011-11-23 | 神州数码网络(北京)有限公司 | Device for carrying out state acquisition and output control on multi-board-card port |
| CN203069679U (en) * | 2013-01-24 | 2013-07-17 | 吉林大学 | Field environment assessment device for nuclear magnetic resonance water exploration instrument |
| CN103323860A (en) * | 2013-05-28 | 2013-09-25 | 中国电子科技集团公司第三十八研究所 | Navigation receiver anti-saturation device based on direct radio frequency sampling |
| CN104297807A (en) * | 2014-09-06 | 2015-01-21 | 吉林大学 | Magnetic resonance imaging device for underground disaster water source detection and detection and imaging method |
| CN204719240U (en) * | 2015-04-22 | 2015-10-21 | 吉林大学 | Nuclear magnetic resonance wide and narrow strip merges amplifier module |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106059520A (en) | 2016-10-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102647241B (en) | Non-coherent detection system and method for short-wave broad-band channel | |
| CN203502550U (en) | Partial discharge live detection device | |
| CN105612428B (en) | Measurement of partial discharge equipment, method for measurement of partial discharge and recording medium | |
| CN106059520B (en) | The real-time anti-saturation device of amplifier and real-time anti-saturation method in water system are visited in magnetic resonance | |
| CN105974343B (en) | Ground magnetic resonance signal detection device with Gain Automatic regulatory function and detection method | |
| US20140025715A1 (en) | Neural Signal Processing and/or Interface Methods, Architectures, Apparatuses, and Devices | |
| Yao et al. | A 0.7 V, 40 nW compact, current-mode neural spike detector in 65 nm CMOS | |
| CN106201128A (en) | Capacitance touching control system and frequency-selecting method thereof | |
| CN105930818A (en) | Data processing method for increasing EMD denoising capability | |
| CN106226630A (en) | A kind of railway system low-frequency AC magnetic fields test system | |
| DE102014211872A1 (en) | Control unit for capacitive touch sensor with automatic gain control | |
| CN110208726A (en) | For the detection system for the outside electromagnetic interference for influencing magnetic resonance system image quality | |
| CN204330901U (en) | A kind of innovative noise sensor | |
| CN104977602B (en) | A kind of control method and device of earthquake data acquisition construction | |
| CN105785458B (en) | The anti-saturation device of ground magnetic resonance signal amplifying circuit and anti-saturation method | |
| CN108009308B (en) | Conducted electromagnetic interference prediction method | |
| CN105611018B (en) | A kind of MIPI LP signal test systems and method | |
| CN111856152A (en) | Pulse signal sampling method and device | |
| CN103149541A (en) | Method for extracting weak signals in magnetic field measurement | |
| CN107270954B (en) | A kind of vibrating string type sensor performance evaluation device and method | |
| CN108983065B (en) | Voltage amplifying circuit, detection circuit and circuit detection method thereof | |
| CN105915198A (en) | Analog-digital mixed filtering method | |
| CN104393851A (en) | Automatic gain control circuit applied to ultrasonic heat meter and control method of automatic gain control circuit | |
| CN205246763U (en) | Airtight space electric field measuring equipment | |
| CN204216856U (en) | A kind of automatic gain control circuit being applied to ultrasonic calorimeter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |