Distributed device and method for detecting groundwater based on nuclear magnetic resonance

Patent metadata

Field	Value
Publication number	US-11397275-B2
Application number	US-202117192920-A
Country	US
Kind code	B2
Filing date	Mar 5, 2021
Priority date	Jul 6, 2020
Publication date	Jul 26, 2022
Grant date	Jul 26, 2022

Abstract

A distributed device and method for detecting groundwater based on nuclear magnetic resonance are provided. The device includes an excitation apparatus, multiple polarization apparatuses, an aerial reception apparatus, and a control apparatus. The aerial reception apparatus includes an array cooled coil sensor. For each of the multiple polarization apparatuses, a position analysis module determines, together with a second position analysis module of the polarization apparatus, a position of the array cooled coil sensor relative to a polarization coil in the polarization apparatus. A polarization transmitter in the polarization apparatus switches to a mode of waiting for output in a case that the array cooled coil sensor is in coverage of the polarization coil. The polarization transmitter in the polarization apparatus remains in a standby mode in a case that the array cooled coil sensor is beyond coverage of the polarization coil.

First claim

The invention claimed is:

1. A distributed device for detecting groundwater based on nuclear magnetic resonance, comprising:
an excitation apparatus configured to generate an excitation magnetic field, to generate a magnetic resonance signal indicating groundwater;
a plurality of polarization apparatuses configured to generate a polarization field to enhance an intensity of the magnetic resonance signal indicating groundwater;
an aerial reception apparatus configured to receive the magnetic resonance signal indicating groundwater; and
a control apparatus comprising a first wireless module and a main control-display module, wherein the main control-display module is configured to configure an operation state and a parameter for the distributed device, transmit the operation state and the parameter via the first wireless module, acquire the magnetic resonance signal received by the aerial reception apparatus via the first wireless module, and display the acquired magnetic resonance signal.

2. The distributed device for detecting groundwater based on nuclear magnetic resonance according to claim 1 , wherein the excitation apparatus comprises:
an excitation transmitter comprising an excitation control module and an alternating current excitation module;
a second wireless module; and
an excitation coil, wherein
the excitation control module is configured to communicate with the control apparatus via the second wireless module to control the alternating current excitation module to generate an excitation current flowing through the excitation coil; and
the second wireless module is connected to the excitation transmitter, and is configured to communicate with the control apparatus to control an output of the excitation transmitter to complete a detection task according to a set time series.

3. The distributed device for detecting groundwater based on nuclear magnetic resonance according to claim 1 , wherein each of the plurality of polarization apparatuses comprises:
a polarization transmitter comprising a polarization control module, a polarization module, and a second position analysis module;
a wireless module; and
a polarization coil, wherein the second position analysis module is configured to communicate with the control apparatus via the wireless module, to control the polarization control module to control an output of the polarization module, to generate a polarization current flowing through the polarization coil.

4. The distributed device for detecting groundwater based on nuclear magnetic resonance according to claim 1 , wherein the plurality of polarization apparatuses have a same structure, and an increasing number of polarization apparatuses are arranged with an increment in an area of a detection region.

5. The distributed device for detecting groundwater based on nuclear magnetic resonance according to claim 3 , wherein the aerial reception apparatus comprises an array cooled coil sensor, a drone, a multi-channel receiver and a third wireless module, wherein
the array cooled coil sensor is suspended from the drone and is connected to the multi-channel receiver via a wire to acquire the magnetic resonance signal;
the drone is configured to carry the array cooled coil sensor and the multi-channel receiver, and is configured to move according to a planned detection routine during detection;
the multi-channel receiver comprises a reception control module, a reception module, and a first position analysis module, wherein the first position analysis module is configured to control the reception control module to control the reception module, and the multi-channel receiver is connected to the array cooled coil sensor to receive the magnetic resonance signal acquired by the array cooled coil sensor and store the received magnetic resonance signal; and
the third wireless module is connected to the multi-channel receiver to control the multi-channel receiver to receive the magnetic resonance signal, and is configured to transmit the received magnetic resonance signal to the control apparatus under the control of the control apparatus.

6. The distributed device for detecting groundwater based on nuclear magnetic resonance according to claim 5 , wherein the first position analysis module is configured to, for each of the plurality of polarization apparatuses, determine, together with the second position analysis module of the polarization apparatus, a position of the array cooled coil sensor relative to a polarization coil in the polarization apparatus, wherein a polarization transmitter in the polarization apparatus switches to a mode of waiting for output in a case that the array cooled coil sensor is in coverage of the polarization coil, and the polarization transmitter in the polarization apparatus remains in a standby mode in a case that the array cooled coil sensor is beyond coverage of the polarization coil.

7. The distributed device for detecting groundwater based on nuclear magnetic resonance according to claim 1 , wherein
the excitation transmitter generates an alternating current ranging from 1A to 400A and a duration of the alternating current ranges from 10 ms to 80 ms;
the plurality of polarization transmitters each generate a polarization current of 200A and a duration of the polarization current ranges from 4 s to 8 s; and
a reception period of the multi-channel receiver is 1000 ms.

8. The distributed device for detecting groundwater based on nuclear magnetic resonance according to claim 1 , wherein the array cooled coil sensor comprises an upper cover, a lower casing, a differential coil array and a low temperature resistant amplifier array, wherein
the differential coil array and the low temperature resistant amplifier array are arranged in the lower casing;
the differential coil array comprises nine differential coils arranged in a slot in the lower casing of the array cooled coil sensor and configured to sense the magnetic resonance signal;
the low temperature resistant amplifier array comprises low-temperature resistant amplifiers respectively connected to the nine differential coils, wherein the low-temperature resistant amplifiers are arranged in the slot in the lower casing of the array cooled coil sensor and are configured to primarily amplify the magnetic resonance signal; and
the upper cover is configured to cover the lower casing after the lower casing is filled with liquid nitrogen for refrigeration.

9. A distributed method for detecting groundwater based on nuclear magnetic resonance, comprising:
a step 1 , arranging an excitation apparatus and a plurality of polarization apparatuses in a detection region, and connecting components in each apparatus;
a step 2 , providing an aerial reception apparatus, and filling an array cooled coil sensor in the aerial reception apparatus with liquid nitrogen for refrigeration;
a step 3 , turning on the excitation apparatus, the plurality of polarization apparatuses and the aerial reception apparatus; setting, in a control apparatus, a parameter for an excitation transmitter in the excitation apparatus, parameters for polarization transmitters respectively in the plurality of polarization apparatuses and a parameter for a multi-channel receiver in the aerial reception apparatus; and controlling the aerial reception apparatus to fly to a preset position;
a step 4 , for each of the plurality of polarization apparatuses, determining, by a first position analysis module together with a second position analysis module of the polarization apparatus, a position of the array cooled coil sensor relative to a polarization coil in the polarization apparatus, wherein a polarization transmitter in the polarization apparatus switches to a mode of waiting for

Assignees

• Univ Jilin

Inventors

• Lin Tingting
• Zhou Kun
• Chen Chao
• Wang Pengfei
• Zhang Yang
• Wan Ling

Classifications

• G01R33/34007

  Manufacture of RF coils, e.g. using printed circuit board technology; additional hardware for providing mechanical support to the RF coil assembly or to part thereof, e.g. a support for moving the coil assembly relative to the remainder of the MR system · CPC title

• G01V3/14 Primary

  operating with electron or nuclear magnetic resonance · CPC title

• G01R33/3415

  comprising arrays of sub-coils {, i.e. phased-array coils with flexible receiver channels} · CPC title

• G01R33/3692

  involving signal transmission without using electrically conductive connections, e.g. wireless communication or optical communication of the MR signal or an auxiliary signal other than the MR signal · CPC title

• G01R33/3621

  NMR receivers or demodulators, e.g. preamplifiers, means for frequency modulation of the MR signal using a digital down converter, means for analog to digital conversion [ADC] or for filtering or processing of the MR signal such as bandpass filtering, resampling, decimation or interpolation · CPC title