CN103257364A - Multi-channel transient electromagnetic instrument receiving circuit - Google Patents
Multi-channel transient electromagnetic instrument receiving circuit Download PDFInfo
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- CN103257364A CN103257364A CN2013101471341A CN201310147134A CN103257364A CN 103257364 A CN103257364 A CN 103257364A CN 2013101471341 A CN2013101471341 A CN 2013101471341A CN 201310147134 A CN201310147134 A CN 201310147134A CN 103257364 A CN103257364 A CN 103257364A
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Abstract
The invention relates to a multi-channel transient electromagnetic instrument receiving circuit which comprises a receiving coil, a low noise amplifier (LNA), a distributor, an attenuator, programmable gain amplifiers (PGAs), analog-to-digital converters (ADCs), a control bus, a data bus and a digital signal processor (DSP). Four channel transient electromagnetic instrument receiving circuits are used for collecting simultaneously, different fixed gain amplification factors are arranged in different channels, the DSP reads signal data of the different channels in a segmented mode, and the signal data are combined into a set of mixed signal data. The DSP restores the mixed signal data according to the fixed amplification factors of the channels. A transient secondary field with high quality can be quickly obtained through the data channels with a low index.
Description
Technical field
The present invention relates to the mine geophysical exploration association area, relate in particular to a kind of hyperchannel Transient Electromagnetic Apparatus receiving circuit of mining Transient Electromagnetic Apparatus.
Background technology
Usually under perfect condition, the signal of transient electromagnetic secondary field can quickly fall to 0.1uV from 8V to mining Transient Electromagnetic Apparatus in the sampling period, if omnidistance undistorted collection, the dynamic range of passage needs 0.1uV to 8V, as Fig. 2.
And in the face of big like this dynamic range, require the data channel noise will be lower than 0.1uV, maximum input voltage will reach 8V, the maximum changing voltage of ADC (analog/digital converter) will reach 8V, least significant bit (LSB) (Lsb:Least significant bit) is wanted to differentiate 0.1uV, presses the Lsb computing formula:
Lsb?=?Vmax/Gmax*2
N
Wherein: Vmax: maximum changing voltage, Gmax: maximum gain, N:ADC changes figure place;
The conversion figure place is 24 ADC, and in maximum changing voltage=8V, Gmax=1 o'clock, Lsb=0.477uV can't differentiate the secondary field of 0.1uV in late period.
According to dynamic range DR computing formula:
DR=20lg（Vmax/Lsb）
Wherein: Vmax: maximum changing voltage, Lsb: least significant bit (LSB);
The conversion figure place is 24 ADC, when maximum changing voltage=8V, and DR=144.5dB,
If the receiving circuit of Transient Electromagnetic Apparatus adopts the single channel programmable gain amplifier, handoff gain can be realized in data acquisition, but needs time delay because gain is switched, and can cause loss of data; If the single channel programmable gain amplifier adopt to switch different gains and carries out repeatedly omnidistance data acquisition, the data of repeatedly gathering to be carried out cutting splice and also can realize, but need the acquisition time of several times, efficient is low.
Summary of the invention
The purpose of this invention is to provide a kind of hyperchannel Transient Electromagnetic Apparatus receiving circuit that can obtain high-quality transition secondary field with the data channel of low index fast.
The present invention is achieved in that a kind of hyperchannel Transient Electromagnetic Apparatus receiving circuit, comprising:
Receiving coil: connect low noise amplifier (LNA), be used for receiving the transient electromagnetic secondary field;
Low noise amplifier (LNA): be connected between receiving coil and the divider, be used for the preposition amplification of signal;
Divider: be connected between low noise amplifier and attenuator and a plurality of programmable gain amplifier, be used for transition secondary field signalling channel and distribute;
Attenuator: be connected between divider and the analog/digital converter, be used for the early stage big voltage signal of transient electromagnetic secondary field and decay to certain ratio, make it can not cause amplifier to enter the saturation region because signal is too high;
Programmable gain amplifier (PGA): be connected between divider and the analog/digital converter, be used for transition secondary field signal and amplify, a plurality of different programmable gain amplifier passages use different gains;
Analog/digital converter (ADC) is connected between digital signal processor (DSP) and attenuator and a plurality of programmable gain amplifier, is used for transition secondary field data-switching;
Control bus: be used for transmitting-receiving transmission control signal and clock signal to LNA, PGA and ADC;
Data bus: be used for data information, can be sent to DSP to the data of ADC;
Digital signal processor (DSP): connect attenuator and a plurality of ADC, be used for transmitting-receiving control signal and clock signal, handle adc data.
Described receiving coil adopts with the colliery and makes of the polythene insulation PVC sheath communication cable, the length of side=1-3 rice, the number of turn=4-20 circle.
Described LNA requires to be folded to input end noise=0.75 nV/ √ Hz; Programmable-gain=1,2,5,8, gain arranges according to the loss of divider.
Described divider loss value 8dB.
Described PGA adopts 3, and gain is respectively 10 times, 100 times and 1000 times.
Described ADC conversion figure place=12, maximum changing voltage=2V.
The attenuation multiple of described attenuator=-40 are to 0 times.
The present invention compared with prior art, advantage is as follows:
The data channel noise of tradition Transient Electromagnetic Apparatus receiving circuit will be lower than 0.1uV, maximum input voltage will reach 8V, the least significant bit (LSB) of ADC (lsb:least significant bit) is wanted to differentiate 0.1uV, and maximum changing voltage will reach 8V, and such technical indicator difficulty is big, cost is high; If adopt the single channel programmable gain amplifier, handoff gain can be realized in data acquisition, but needs time delay because gain is switched, and can cause loss of data; If the single channel programmable gain amplifier adopt to switch different gains and carries out repeatedly omnidistance data acquisition, the data of repeatedly gathering to be carried out cutting splice and also can realize, but need the acquisition time of several times, efficient is low.
The present invention utilizes 4 passage Transient Electromagnetic Apparatus receiving circuits to gather simultaneously, different passages arrange different fixed gain enlargement factors, different channel signal data are read in the DSP segmentation, synthetic one group of mixed signal data, and DSP reduces the intrinsic enlargement factor of the data based passage of mixed signal.As long as being lower than 50uV(, the data channel noise requires low 500 times than 0.1uV), maximum input voltage reaches 2V(and requires low 4 times than 8V), the least significant bit (LSB) Lsb of ADC equals 30.5uV(and requires low 305 times than 0.1uV), maximum changing voltage reaches 2V(and requires low 4 times than 8V), just can obtain high-quality transition secondary field fast with the data channel of low index.
Description of drawings
The present invention is further illustrated in conjunction with the embodiments with reference to the accompanying drawings.
Fig. 1 is the structural representation of hyperchannel Transient Electromagnetic Apparatus receiving circuit of the present invention.
The signal sampling curve map of the transient electromagnetic secondary field under Fig. 2 perfect condition.
Fig. 3 is the actual signal sampling curve map that is subjected to the transient electromagnetic secondary field after the analog channel background noise disturbs.
Fig. 4 is the signal sampling curve map of secondary field of the A channel of hyperchannel Transient Electromagnetic Apparatus receiving circuit of the present invention.
Fig. 5 is the signal sampling curve map of secondary field of the B passage of hyperchannel Transient Electromagnetic Apparatus receiving circuit of the present invention.
Fig. 6 is the signal sampling curve map of secondary field of the C-channel of hyperchannel Transient Electromagnetic Apparatus receiving circuit of the present invention.
Fig. 7 is the signal sampling curve map of secondary field of the D passage of hyperchannel Transient Electromagnetic Apparatus receiving circuit of the present invention.
Fig. 8 is the signal sampling curve map that the DSP of hyperchannel Transient Electromagnetic Apparatus receiving circuit of the present invention intercepts the secondary field that obtains after the data mixing in each distortionless interval of passage.
Fig. 9 is the signal sampling curve map of DSP secondary field of obtaining after reduction of hyperchannel Transient Electromagnetic Apparatus receiving circuit of the present invention.
Embodiment
As Fig. 1, be the structural representation of a kind of hyperchannel Transient Electromagnetic Apparatus receiving circuit of the present invention, comprising:
(1) receiving coil: be used for receiving the transient electromagnetic secondary field, make the length of side=1-3 rice, the number of turn=4-20 circle of the colliery of the polythene insulation PVC sheath communication cable;
(2) low noise amplifier: Low Noise Amplifier is called for short LNA, is used for the preposition amplification of signal, requires to be folded to input end noise=0.75 nV/ √ Hz; Programmable-gain=1,2,5,8, gain arranges according to the loss of divider;
(3) divider: be used for transition secondary field signalling channel and distribute.Distribution loss Ls what and distribute port number n's is how much relevant, Ls=10*lg n in the ideal case, when n=4, distribution loss is 6dB, in fact except the loss that waits sub-signal, some is because distribution devices itself has decay, thus always big than calculated value, this divider loss value 8dB;
(4) programmable gain amplifier: Programmable gain amplifier is called for short PGA, is used for transition secondary field signal and amplifies, and different passages is respectively with different gains, 3 channel gains: 10 times, 100 times, 1000 times;
(5) analog/digital converter: Analog-to-Digital Converter is called for short ADC, is used for transition secondary field data-switching.ADC conversion figure place=12, maximum changing voltage=2V;
Press the Lsb computing formula:
Lsb?=?Vmax/Gmax*2N
Wherein: Vmax: maximum changing voltage, Gmax: maximum gain, N:ADC changes figure place;
ADC conversion figure place=16, maximum changing voltage=2V
Gmax=1 o'clock, Lsb=30.51uV;
Gmax=10 o'clock, Lsb=3.05uV;
Gmax=100 o'clock, Lsb=0.31uV;
Gmax=1000 o'clock, Lsb=0.03uV;
Attenuator: be used for the early stage big voltage signal of transient electromagnetic secondary field and decay to certain ratio, can not enter the saturation region by amplifier because signal is too high, attenuation multiple in the present embodiment=-40 are to 0 times;
(6) control bus: Control Bus, be mainly used to transmitting-receiving transmission control signal and clock signal to LNA, PGA, ADC, control signal comprises gain multiple control signal, read/write signal, chip selection signal, reset signal, bus request signal, device ready signal etc.;
(7) data bus: DataBus is used for data information, can be sent to DSP to the data of ADC, in the present embodiment, and bus bits=16;
(8) digital signal processor: Digital Signal Processor is called for short DSP, is used for transmitting-receiving control signal and clock signal, handles adc data.
The principle of work of described hyperchannel Transient Electromagnetic Apparatus receiving circuit is as follows:
(1) receiving coil receives transition secondary field signal, and under the perfect condition, the signal of transient electromagnetic secondary field can quickly fall to 0.1uV from 8V in the sampling period, and omnidistance undistorted collection needs 0.1uV to the dynamic range 144dB of 8V, as Fig. 2;
(2) actual in the analog channel background noise all can reach more than the 1uV, condition restriction such as the maximum changing voltage of ADC, transition secondary early signal meeting clipped wave, late period, signal was submerged, and caused the overall signal distortion, as Fig. 3;
(3) do the preposition amplification of secondary field signal with LNA, it is fixed that gain amplifier comes according to the attenuation multiple value of divider; Divider is all given 4 data passages with the signal of LNA output; A channel is made up of attenuator and ADC, mainly receives transition secondary field early signal, and attenuation multiple=-40 dB to 0 dB is according to arranging with transition secondary field intensity actual needs; The B-D passage is made up of PGA and ADC, mainly receive in the transition secondary field, late period signal, the gain be respectively 10 times, 100 times, 1000 times;
(4) attenuation multiple is arranged is-40 to 0 times attenuator to A channel, and overall signal is attenuated.If transition secondary field early signal maximal value decays to 1.14V from 8V, and the maximum changing voltage=2V of ADC, A channel can intactly keep the early signal original appearance, though Lsb=30.5uV of ADC, but the overall noise of passage is 50uV, in, late period signal flooded by noise, can't identify, the overall signal distortion is as Fig. 4;
(5) the B channel gain is 10 times, and overall signal is exaggerated 10 times, and early signal is exaggerated, and surpasses 2V and clipped wave, and distortion strengthens, in, late period signal amplitude low, flooded by noise, the overall signal distortion is as Fig. 5;
(6) the C-channel gain is 100 times, and overall signal is exaggerated 100 times, and early signal is exaggerated, and surpasses 2V signal clipped wave, and distortion strengthens, and the distortion in mid-term disappears, and late period, distortion also existed, and the overall signal distortion is as Fig. 6;
(7) the D channel gain is 1000 times, and overall signal is exaggerated 1000 times, and early signal is exaggerated, and surpasses 2V signal clipped wave, and distortion strengthens, and the distortion in late period disappears, and the overall signal distortion is as Fig. 7;
(8) DSP reads the signal data in T0-T1 interval at A channel, read the signal data in T1-T2 interval at the B passage, read the signal data in T2-T3 interval at C-channel, get the signal data in T3-T4 interval at D passage degree, with different passages, different interval, different amplification but distortionless signal data is mixed into one group of data, as Fig. 8;
(9) DSP dB value that the data of T0-T1 are pressed attenuator is amplified reduction, and the data in T1-T2 interval are amplified-10 times of reduction, and the data in T2-T3 interval are amplified-100 times of reduction, and the data in T3-T4 interval are amplified-1000 times of reduction.Data from T0 to T4 make up in order, with regard to having reduced transition secondary field signal truly, as Fig. 9.
The present invention utilizes 4 passage Transient Electromagnetic Apparatus receiving circuits to gather simultaneously, different passages arrange different fixed gain enlargement factors, different channel signal data are read in the DSP segmentation, synthetic one group of mixed signal data, and DSP reduces the intrinsic enlargement factor of the data based passage of mixed signal.As long as being lower than 50uV(, the data channel noise requires low 500 times than 0.1uV), maximum input voltage reaches 2V(and requires low 4 times than 8V), the least significant bit (LSB) Lsb of ADC equals 30.5uV(and requires low 305 times than 0.1uV), maximum changing voltage reaches 2V(and requires low 4 times than 8V), just can obtain high-quality transition secondary field fast with the data channel of low index.
Claims (7)
1. hyperchannel Transient Electromagnetic Apparatus receiving circuit comprises:
Receiving coil: connect LNA, be used for receiving the transient electromagnetic secondary field;
LNA: be connected between receiving coil and the divider, be used for the preposition amplification of signal;
Divider: be connected between LNA and attenuator and a plurality of PGA, be used for transition secondary field signalling channel and distribute;
Attenuator: be connected between divider and the ADC, be used for the early stage big voltage signal of transient electromagnetic secondary field and decay to certain ratio, make it can not cause amplifier to enter the saturation region because signal is too high;
PGA: be connected between divider and the ADC, be used for transition secondary field signal and amplify, a plurality of different PGA passages use different gains;
ADC: be connected between DSP and attenuator and a plurality of PGA, be used for transition secondary field data-switching;
Control bus: be used for transmitting-receiving transmission control signal and clock signal to LNA, PGA and ADC;
Data bus: be used for data information, can be sent to DSP to the data of ADC;
DSP: connect attenuator and a plurality of ADC, be used for transmitting-receiving control signal and clock signal, handle adc data.
2. hyperchannel Transient Electromagnetic Apparatus receiving circuit according to claim 1 is characterized in that: described receiving coil employing colliery polythene insulation PVC sheath communication cable making, the length of side=1-3 rice, the number of turn=4-20 circle.
3. hyperchannel Transient Electromagnetic Apparatus receiving circuit according to claim 2 is characterized in that: described LNA requires to be folded to input end noise=0.75 nV/ √ Hz; Programmable-gain=1,2,5,8, gain arranges according to the loss of divider.
4. hyperchannel Transient Electromagnetic Apparatus receiving circuit according to claim 1 is characterized in that: described divider loss value 8dB.
5. hyperchannel Transient Electromagnetic Apparatus receiving circuit according to claim 1 is characterized in that: described PGA adopts 3, and gain is respectively 10 times, 100 times and 1000 times.
6. hyperchannel Transient Electromagnetic Apparatus receiving circuit according to claim 1 is characterized in that: described ADC conversion figure place=12, maximum changing voltage=2V.
7. hyperchannel Transient Electromagnetic Apparatus receiving circuit according to claim 1, it is characterized in that: the attenuation multiple of described attenuator=-40 are to 0 times.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108459201A (en) * | 2018-03-09 | 2018-08-28 | 中国科学院上海微系统与信息技术研究所 | A kind of the mixing sampling system and method for transient signal |
| CN113655526A (en) * | 2021-08-31 | 2021-11-16 | 中煤科工集团重庆研究院有限公司 | Real-time imaging method and system based on dynamic transient electromagnetism |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070285096A1 (en) * | 2006-06-09 | 2007-12-13 | Hitachi, Ltd. | Double-tuned RF coil |
| US20080129298A1 (en) * | 2006-02-17 | 2008-06-05 | Vaughan J T | High field magnetic resonance |
| CN102707321A (en) * | 2012-06-05 | 2012-10-03 | 北京工业大学 | Receiving and collecting system and method for transient electromagnetic instrument |
| CN103048696A (en) * | 2012-12-20 | 2013-04-17 | 福州华虹智能科技开发有限公司 | Transmitting and receiving device of mining transient electromagnetic instrument |
-
2013
- 2013-04-25 CN CN2013101471341A patent/CN103257364A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080129298A1 (en) * | 2006-02-17 | 2008-06-05 | Vaughan J T | High field magnetic resonance |
| US20070285096A1 (en) * | 2006-06-09 | 2007-12-13 | Hitachi, Ltd. | Double-tuned RF coil |
| CN102707321A (en) * | 2012-06-05 | 2012-10-03 | 北京工业大学 | Receiving and collecting system and method for transient electromagnetic instrument |
| CN103048696A (en) * | 2012-12-20 | 2013-04-17 | 福州华虹智能科技开发有限公司 | Transmitting and receiving device of mining transient electromagnetic instrument |
Non-Patent Citations (1)
| Title |
|---|
| 王远: "一种便携式多通道瞬变电磁探测系统的设计与实现", 《中国优秀硕士学位论文全文数据库（工程科技II辑）》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108459201A (en) * | 2018-03-09 | 2018-08-28 | 中国科学院上海微系统与信息技术研究所 | A kind of the mixing sampling system and method for transient signal |
| CN113655526A (en) * | 2021-08-31 | 2021-11-16 | 中煤科工集团重庆研究院有限公司 | Real-time imaging method and system based on dynamic transient electromagnetism |
| CN113655526B (en) * | 2021-08-31 | 2024-03-12 | 中煤科工集团重庆研究院有限公司 | Real-time imaging method and system based on dynamic transient electromagnetic |
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Application publication date: 20130821 |