CN114137460B - Radio frequency array coil system - Google Patents
Radio frequency array coil system Download PDFInfo
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- CN114137460B CN114137460B CN202111404342.6A CN202111404342A CN114137460B CN 114137460 B CN114137460 B CN 114137460B CN 202111404342 A CN202111404342 A CN 202111404342A CN 114137460 B CN114137460 B CN 114137460B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/44—Arrangements or instruments for measuring magnetic variables involving magnetic resonance using nuclear magnetic resonance [NMR]
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
- G01R33/32—Excitation or detection systems, e.g. using radio frequency signals
- G01R33/36—Electrical details, e.g. matching or coupling of the coil to the receiver
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
- G01R33/42—Screening
- G01R33/422—Screening of the radio frequency field
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
Abstract
The invention discloses a radio frequency array coil system. A radio frequency array coil system comprising: the device comprises a power divider, a radio frequency transceiving component, an array coil and a preamplifier; the power distributor is connected with the radio frequency transceiving components and is used for carrying out multi-path distribution on the input high-power radio frequency and distributing the same power to the corresponding radio frequency transceiving components; the radio frequency transceiving component is connected with the array coil in a matching way and is used for driving the array coil to transmit and receive signals; the array coil is composed of a plurality of annular coils which are arranged on the cylindrical support in a surrounding mode, and the annular coils are not connected with each other in a geometric overlapping mode or a physical structure and used for generating a circularly polarized transmitting field; a preamplifier is placed at a predetermined distance from each of the loop coils for receiving signals generated by the array coils. The multi-channel power distribution is realized, a uniform transmitting field is generated, the performance of the array coil is improved, and the sensitivity of signal acquisition is improved.
Description
Technical Field
The embodiment of the invention relates to a nuclear magnetic resonance technology, in particular to a radio frequency array coil system.
Background
Ultra-high field animal Magnetic Resonance Imaging (MRI) is a valuable technique in biomedical research that has proven to provide excellent resolution and anatomical detail. By exploring the morphological features and associated physiological or pathological functions provided by the ultra-high field animal images, human disease can be studied and inferred. Radio Frequency (RF) coils, the development of which is of great importance for biomedical research, realize the high sensitivity and critical components of MR imaging quality that ultra-high fields provide.
The existing 9.4T standard coil has certain limitation, and cannot fully utilize the advantages brought by higher field intensity. The standard volume birdcage coil is a quadrature transmit-receive coil, and the phase setting of the quadrature transmission channels can cause typical destructive interference at the periphery of the sample, resulting in a reduced signal-to-noise ratio at the surface, such as in brain imaging, in cortical areas where neuroscience is a major concern. As the larmor frequency increases, the wavelength of the relevant RF approaches the size of the object to be imaged, resulting in an uneven transmission field generated by the RF coil, and in ultra-high field large sample imaging applications, the enhanced interaction between different channels, mutual coupling between channels, and complex electromagnetic wave behavior in high-intensity electromagnetic fields, dielectric and conductive biological samples, etc. can severely degrade the transmission efficiency and reception sensitivity of the coil.
Disclosure of Invention
The invention provides a radio frequency array coil system, which is used for realizing multi-channel power distribution, generating a uniform transmitting field, improving the performance of an array coil and improving the sensitivity of signal acquisition.
The embodiment of the invention provides a radio frequency array coil system, which comprises: the device comprises a power divider, a radio frequency transceiving component, an array coil and a preamplifier;
the power distributor is connected with the radio frequency transceiving components and is used for carrying out multi-path distribution on input high-power radio frequencies and distributing the same power to the corresponding radio frequency transceiving components;
the radio frequency transceiving component is connected with the array coil in a matching way and is used for driving the array coil to transmit and receive signals;
the array coil is composed of a plurality of annular coils, the plurality of annular coils are arranged on the cylindrical support in a surrounding mode, and the plurality of annular coils are not connected with each other in a geometric overlapping mode or a physical structure and are used for generating a circularly polarized transmitting field;
the preamplifier is placed at a predetermined distance from each of the toroidal coils for receiving signals generated by the array coils.
Optionally, the power divider includes a quadrature coupler and a power divider, where the quadrature coupler includes a first quadrature coupler and a second quadrature coupler;
the first orthogonal coupler is connected with the two second orthogonal couplers and is used for distributing high-power radio frequency input by the radio frequency power amplifier to the two second orthogonal couplers;
each second orthogonal coupler is connected with two power dividers and is used for distributing the radio frequency transmitted by the first orthogonal coupler to the two power dividers.
Optionally, the radio frequency array coil system further includes: a phase shifter;
the phase shifter is connected between the quadrature coupler and the power divider, and between the power divider and the annular coil, and is configured to adjust a phase of a transmitted radio frequency.
Optionally, coaxial cables with different lengths are matched between the quadrature coupler and the power divider to change amplitudes and modulation phases of excitation sources of different channels.
Optionally, a cable trap is disposed on the coaxial cable, and is configured to suppress an unbalanced current on the coaxial cable and protect the preamplifier.
Optionally, each of the toroidal coils uses a copper strip as a conductor, and the copper strips are uniformly distributed to generate uniform current in each of the toroidal coil loops.
Optionally, the radio frequency array coil system further includes: an electromagnetic shielding means;
the electromagnetic shielding device is connected with the array coil and used for preventing the array coil from being subjected to electromagnetic interference.
Optionally, the electromagnetic shielding device is made of slotted copper foil, and the slotted copper foil is distributed at equal intervals to form a cylindrical surface and is located above the array coil.
Optionally, the rf transceiver module and the preamplifier are integrated on a circuit board, so as to reduce interference between the trace and the circuit.
The invention distributes the input high-power radio frequency in multiple paths through the power distributor, distributes the same power to the corresponding radio frequency transceiving components, arranges multiple annular coils which are not mutually overlapped in geometric way and are not connected in physical structure, and forms an array coil by surrounding the cylindrical bracket, solves the problems of low transmission efficiency and low receiving sensitivity of the coils and the problem of non-uniform radio frequency magnetic field, realizes the multi-channel power distribution, generates uniform transmitting field, improves the performance of the array coil and improves the effect of the sensitivity of signal acquisition.
Drawings
Fig. 1 is a schematic structural diagram of a radio frequency array coil system according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of an array coil according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of another radio frequency array coil system according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of the amplitude and phase shift at the output end of 8 channels of an RF array coil system according to an embodiment of the present invention;
fig. 5 is a schematic structural diagram of an electromagnetic shielding apparatus of a radio frequency array coil system according to an embodiment of the present invention;
fig. 6 is a schematic circuit diagram of a toroidal coil and an rf front end thereof according to a second embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
Example one
Fig. 1 is a schematic structural diagram of a radio frequency array coil system according to an embodiment of the present invention, which is applicable to the situation of ultra-high magnetic field magnetic resonance imaging, and the method can be performed by a radio frequency array coil system, as shown in fig. 1, the radio frequency array coil system includes: power divider 100, radio frequency transceiver module 200, array coil 300, preamplifier 400;
the power divider 100 is connected to the rf transceiver module 200, and configured to perform multi-path distribution on the input high power rf, and distribute the same power to the corresponding rf transceiver module 200;
the radio frequency transceiver component 200 is connected with the array coil 300 in a matching manner, and is used for driving the array coil 300 to transmit and receive signals;
the array coil 300 is composed of a plurality of annular coils which are arranged around a cylindrical support, and the plurality of annular coils are not connected with each other in a geometric overlapping or physical structure and are used for generating a circularly polarized transmitting field;
the preamplifier 400 is placed at a predetermined distance from each of the loop coils for receiving the signals generated by the array coils 300.
The power divider 100 divides the high power radio frequency input by the radio frequency power amplifier into multiple paths of different powers, and outputs the multiple paths of different powers through the radio frequency transceiving component 200, and simultaneously the power divider 100 is matched with coaxial cables with different lengths to realize the adjustment and control of the amplitude and the phase of each channel excitation source and the distribution of the multiple paths of powers, so that the array coil 300 can generate a circularly polarized transmitting field. Because the input cable generates common-mode current under the induction of an external electromagnetic field, the common-mode current can cause interference to other devices, and further, a balun is added on the input cable of each transmission path so as to reduce the common-mode current on the outer shielding layer of the coaxial cable to the maximum extent.
The rf transceiver module 200 outputs rf signals with the same power and different phases to the corresponding array coil 300, and the rf transceiver module realizes the function of integrating the transmitting signal and the receiving signal of the array coil 300, so as to reduce the loss caused by the lumped elements in the ultra-high field.
As shown in fig. 2, the array coil 300 is composed of a plurality of circular coils 310, for example, preferably 8, 8 circular coils 310 are wound on a cylindrical support (not shown) to form a circular polarization excitation pattern, and the formed array coil 300 can image the whole imaging object at all angles. The geometric spacing between the 8 toroidal coils 310 is adjusted, so that the 8 toroidal coils 310 are not connected with each other by geometric overlapping or physical structures, the coupling between adjacent and next adjacent elements is reduced to the maximum extent, an additional reactance decoupling strategy is not needed, and the coupling problem between different coils is solved. As shown in fig. 2, groupThe elements 311 in each loop of the loop coil 310 are uniformly distributed, and optionally, each loop coil 310 uses copper strips as conductors of the elements 311, and the copper strips are uniformly distributed, so that uniform current is generated in each loop coil 310. Illustratively, the copper strip is 4mm wide and 0.15mm thick. Further, non-magnetic variable parallel and series capacitors are used for tuning and matching with their respective transceiver channels to ensure optimal performance of the constructed toroid 310. Correspondingly, 8 preamplifiers, which are low noise preamplifiers, are placed at a quarter wavelength distance from each loop coil and receive the signals generated by the array coils. Optionally, the radio frequency transceiver component and the preamplifier are integrated on a circuit board, and interference between wires and circuits in the radio frequency array coil system can be reduced. The toroidal coil in this embodiment is 1 Coil of H nuclide of 1 Imaging of H nuclear species, in alternate embodiments, the loop coil can be extended to any nuclear species of interest, while the radio frequency array coil system is not limited to ultra-high field animal systems, but can be extended to any supportable magnetic resonance system.
As shown in fig. 3, optionally, the power divider 100 includes a quadrature coupler 110 and a power divider 120, where the quadrature coupler 110 includes a first quadrature coupler 111 and a second quadrature coupler 112;
the first quadrature coupler 111 is connected to the two second quadrature couplers 112, and is configured to distribute a high-power radio frequency input by a radio frequency power amplifier to the two second quadrature couplers 112;
each of the second orthogonal couplers 112 is connected to two of the power splitters 120, and is configured to distribute the radio frequency transmitted by the first orthogonal coupler 111 to two of the power splitters 120.
The power divider 100 adopts a first orthogonal coupler 111 and a second orthogonal coupler 112 which are cascaded, the second orthogonal coupler 112 is further cascaded with a power divider 120 of 1. The input end of the first quadrature coupler 111 is used for connecting an external rf power amplifier, so that a high-power rf signal input by the rf power amplifier is distributed into 8 paths of signals, and is output to the corresponding 8 ring coils through the power divider 120.
As shown in fig. 3, the radio frequency array coil system further includes: a phase shifter 130;
the phase shifter 130 is connected between the quadrature coupler 110 and the power divider 120, and between the power divider 120 and the loop coil, and is configured to adjust a phase of a transmitted radio frequency.
Optionally, coaxial cables with different lengths are matched between the quadrature coupler 110 and the power divider 120, so as to change amplitudes and modulation phases of excitation sources of different channels.
Only one phase shifter 130 is connected between the first quadrature coupler 111 and one second quadrature coupler 112, the phase shifter 130 is connected between the second quadrature coupler 112 and the two corresponding 1. The amplitude and phase regulation of each channel excitation source can be realized by simultaneously matching coaxial cables with different lengths in the cascaded power divider, 8 paths of signals are separated, and finally amplitude change and phase modulation of each channel excitation source are realized to generate a circularly polarized transmitting field. The amplitude and phase control of the excitation sources of each channel is shown in fig. 4, which shows the amplitude and phase offsets of 8 outputs of the rf transceiver module, specifically, according to the position of the azimuth angle of the coil, a gradually decreasing 45 ° phase offset is provided at each output of the rf transceiver module in a clockwise direction until the coil is circularly polarized at the rightmost end. The insertion loss after the cascade connection can be reduced by adopting coaxial lines with different lengths to realize phase shift.
Optionally, a cable trap is disposed on the coaxial cable, and is configured to suppress an unbalanced current on the coaxial cable and protect the preamplifier.
In order to protect the preamplifier, a cable trap is arranged on each channel, the unbalanced current on the coaxial cable is restrained by the cable trap, and the cable trap is arranged between each connected annular coil and the preamplifier.
As shown in fig. 5, the radio frequency array coil system further includes: an electromagnetic shielding device 500;
the electromagnetic shielding device 500 is connected to the array coil 300 for preventing the array coil 300 from being subjected to electromagnetic interference.
The electromagnetic shielding device 500 is connected to the array coil 300 to reduce radiation loss, minimize eddy currents, and prevent the array coil 300 from being electromagnetically interfered by other hardware components of the scanner, so as to maintain the tuning condition of the coils inside the magnet, and complete the rf excitation and acquisition chain of the 8-channel array coil 300.
Optionally, the electromagnetic shielding device 500 is made of a slotted copper foil, and is distributed equidistantly to form a cylindrical surface above the array coil 300.
Illustratively, the electromagnetic shielding device 500 is made of slotted copper foil, the side surface of the electromagnetic shielding device 500 is composed of 19 copper segments, the copper segments are equidistantly distributed on the inner surface of a PVC cylinder to form a cylindrical surface, the interval of each copper segment is 3mm, 54 shielding capacitors with equal capacitance values are distributed and connected in the cylindrical surface, further, 5 copper segments are distributed at the bottom of the cylinder, the 5 shielding capacitors are distributed and connected at the gaps of the copper segments, and the influence of the magnet on the resonance frequency shift caused by the array coil action can be better reduced by selecting the shielding capacitor with the proper capacitance value. Placement of the radio frequency shield 500 at a distance of 4cm above the array coil 300 reduces radiation losses to the array coil 300 without increasing the overall height of the array coil 300 housing geometry, exceeding the geometric constraints of the magnet aperture, and without compromising the field distribution of the loop elements.
According to the technical scheme of the embodiment, 8 paths of input high-power radio frequency are distributed through a power distributor, the same power is distributed to corresponding radio frequency transceiving components, 8 annular coils which are not in geometric overlapping or physical structure connection are arranged among the annular coils, and the annular coils surround a cylindrical support to form an array coil, so that a circular polarization excitation mode condition is formed, the whole imaging object can be imaged in an all-around and multi-angle manner, and the coupling problem among different coil units is ideally solved by adjusting the geometric spacing among the annular coils because the annular coils are not in geometric overlapping or physical structure connection; the 8-path power divider is matched with coaxial cables with different lengths, so that amplitude and phase regulation of each channel excitation source are realized to generate a circularly polarized transmitting field, and phase shift can be realized to reduce insertion loss after cascade connection; the two-stage quarter-wave coil is adopted to improve the isolation of transmitting and receiving, solve the problems of low transmission efficiency and low receiving sensitivity of the coil, improve the performance of the array coil and improve the sensitivity of signal acquisition.
Example two
Fig. 6 is a schematic circuit diagram of a toroidal coil and a radio frequency front end thereof according to a second embodiment of the present invention, in this embodiment, a 1-way output of a power divider is taken as an example for explanation, as shown in fig. 6, a toroidal coil L1 is formed by connecting four spaced components through capacitors C, a power divider 100 is connected to an 8-way radio frequency transceiver module 200, the radio frequency transceiver module 200 includes a transmit (T/R) switch, and the power divider 100 is connected to an array coil 300 through the transmit switch. The uniform distribution of components in the toroid L1 causes uniform current to be generated in the coil loop, and further, non-magnetic variable parallel and series capacitors are used for tuning and matching with their respective transceiver channels to ensure optimal performance of the constructed toroid L1. The loop coil L1 is matched to 50 Ω and tuned to 400.3MHz by the matching circuit 30, the matching circuit 30 is connected in series to the feeding point F, and the matching circuit 30 in this embodiment is an adjustable capacitor Cm; one end of the matching circuit 30 is connected to the feeding point F through the coaxial cable A3 and the balun 20, the other end of the matching circuit 30 is connected to the loop coil L1 and a first end of a tuning capacitor Ct, and a second end of the tuning capacitor Ct is connected to the loop coil L1. The balun 20 for reducing the common-mode current of the outer shielding layer of the coaxial cable is formed by winding a nonmagnetic semisteel coaxial cable with 2 turns of balun and connecting C-series capacitors in series, the tuning is carried out to 400.3MHz, and the emission coefficient reaches-33 dB; in order to suppress the cable trap of the unbalanced current on the coaxial cable, the parallel resonance trap circuit 40 is formed by winding 2 turns of balun on a 1/2 flexible coil decoupling inductance frame, illustratively, resonance capacitors are series capacitors of 4.7pF and 3pF B, the series capacitors are tuned to 400.3MHz, and the reflection coefficient value of a radio frequency test signal is-30 dB; the preamplifiers are placed at a distance of one quarter wavelength from each of the toroids to reduce interference between the traces and the circuitry. The radio frequency front-end circuit is also provided with a direct current bias port to access direct current bias current.
A direct current bias port of a direct current bias circuit 10 in a radio frequency front end circuit is connected with a direct current bias current, a radio frequency test signal sent by a scanner is sent from a transmitting end of a channel Ch1 of a power divider 100, passes through a first capacitor C1, a first diode D1 and a first quarter-wavelength line A1, reaches a feeding point F, is input into a loop coil L1 from the feeding point F through a balance-unbalance converter 20, a matching circuit 30 and a tuning capacitor Ct, and is orthogonally excited by loop coils connected with other channels to generate a circularly polarized transmitting field; the input end of the preamplifier P is connected with a second quarter-wavelength line A2 and a second capacitor C2, the preamplifier P is placed at a distance of a quarter wavelength from the annular coil L1 and is used for receiving nuclear magnetic resonance signals collected by the annular coil L1, the nuclear magnetic resonance signals reach the preamplifier P from the feed point F through the second quarter-wavelength line A2 and the second capacitor C2 for amplification, then reach the receiving end of the power divider through the parallel resonance trap circuit 40 for input, and then are transmitted to the spectrometer to complete image reconstruction and display a nuclear magnetic resonance imaging result; wherein the preamplifier P is a low noise preamplifier.
Illustratively, the 8-loop coil is fully matched to 50 ohms at the frequency of 400.3MHz, the transmission coefficients of all the loop coils are less than-20 dB, the isolation between any two loop coils is less than-11 dB, and the coupling problem between coil units is solved; in the transmitting state, the insertion loss and the isolation of the radio frequency transceiving component are respectively less than 0.7dB and-46 dB, and in the receiving state, the reflection coefficient and the isolation are respectively less than-12 dB and-25 dB, so that the excitation and collection states are quickly switched, and the effect of mutual interference between transmitting and receiving radio frequency paths is avoided; the absolute amplitude and the phase deviation standard deviation of the eight radio frequency test signals generated under the working frequency of 400.3MHz are respectively less than 0.3dB and 1 degree, 8-channel power distribution is realized, and a uniform circularly polarized transmitting field is generated after the radio frequency power output is driven to pass through the coil array.
The receiving and transmitting integrated design of the radio frequency receiving and transmitting component realizes a signal excitation and acquisition chain with required frequency for imaging, and through the rapid switching of excitation and acquisition states, the capability of mutual interference between transmitting and receiving radio frequency paths is avoided, and the problem that the uniformity of a transmitting field of a large coil deteriorates under high frequency is solved. The two-stage quarter-wave line is adopted to improve the isolation of transmission and reception, reduce the parasitic parameters of discrete devices under the radio frequency transmission frequency of an ultra-high field system and solve the problem that the difference of welding processes can deteriorate the radio frequency performance of a circuit and increase the loss of the circuit. The radio frequency receiving and transmitting assembly and the preamplifier are integrated on one circuit board, so that the interference between the wiring and the circuit is reduced.
It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in some detail by the above embodiments, the invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the invention, and the scope of the invention is determined by the scope of the appended claims.
Claims (7)
1. A radio frequency array coil system, comprising: the device comprises a power divider, a radio frequency transceiving component, an array coil, a preamplifier and a phase shifter;
the power distributor is connected with the radio frequency transceiving components and is used for carrying out multi-path distribution on input high-power radio frequency and distributing the same power to the corresponding radio frequency transceiving components;
the radio frequency transceiving component is connected with the array coil in a matching way and is used for driving the array coil to transmit and receive signals;
the array coil is composed of a plurality of annular coils, the plurality of annular coils are arranged on the cylindrical support in a surrounding mode, and the plurality of annular coils are not connected with each other in a geometric overlapping mode or a physical structure and are used for generating a circularly polarized transmitting field;
the preamplifier is placed at a preset distance from each annular coil and used for receiving signals generated by the array coils;
the power divider comprises a quadrature coupler and a power divider, wherein the quadrature coupler comprises a first quadrature coupler and a second quadrature coupler;
the first orthogonal coupler is connected with the two second orthogonal couplers and is used for distributing high-power radio frequency input by the radio frequency power amplifier to the two second orthogonal couplers;
each second orthogonal coupler is connected with two power dividers and is used for distributing radio frequency sent by the first orthogonal coupler to the two power dividers;
the phase shifter is connected between the quadrature coupler and the power divider, and between the power divider and the annular coil, and is configured to adjust a phase of a transmitted radio frequency.
2. The radio frequency array coil system according to claim 1, wherein coaxial cables with different lengths are coupled between the quadrature coupler and the power divider for changing amplitudes and modulation phases of excitation sources of different channels.
3. A radio frequency array coil system as set forth in claim 2, wherein a cable trap is disposed on the coaxial cable for suppressing unbalanced current on the coaxial cable and protecting the preamplifier.
4. A radio frequency array coil system as set forth in claim 1, wherein each of said loop coils uses copper strips as conductors, said copper strips being uniformly distributed for producing uniform current in each of said loop coil loops.
5. A radio frequency array coil system as set forth in claim 1, further comprising: an electromagnetic shielding means;
the electromagnetic shielding device is connected with the array coil and used for preventing the array coil from being subjected to electromagnetic interference.
6. A radio frequency array coil system as set forth in claim 5, wherein said electromagnetic shielding means is made of slotted copper foil equally spaced to form a cylindrical surface above said array coil.
7. The rf array coil system of claim 1, wherein the rf transceiver component and the preamplifier are integrated on a circuit board for reducing interference between traces and circuitry.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111404342.6A CN114137460B (en) | 2021-11-24 | 2021-11-24 | Radio frequency array coil system |
| PCT/CN2021/136741 WO2023092673A1 (en) | 2021-11-24 | 2021-12-09 | Radio frequency array coil system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111404342.6A CN114137460B (en) | 2021-11-24 | 2021-11-24 | Radio frequency array coil system |
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| CN114137460A CN114137460A (en) | 2022-03-04 |
| CN114137460B true CN114137460B (en) | 2023-03-24 |
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| CN201691927U (en) * | 2010-06-29 | 2011-01-05 | 中国科学院生物物理研究所 | Parallel transmission receiving radio frequency interface circuit and phased array transmission receiver coil |
| CN101872001B (en) * | 2010-06-29 | 2012-11-07 | 中国科学院生物物理研究所 | Parallel emitting and receiving radio-frequency interface circuit and phased array emitting and receiving head coil |
| KR101424976B1 (en) * | 2012-11-08 | 2014-08-13 | 삼성전자주식회사 | Phased array RF coil for magnetic resonance imaging |
| US20150309132A1 (en) * | 2014-04-24 | 2015-10-29 | New York University | Apparatus, method and coil array for providing split parallel transmission magnetic resonance imaging |
| CN104698411B (en) * | 2015-02-13 | 2018-06-22 | 江苏麦格思频仪器有限公司 | For the Multi-channel radio-frequency coil of open type magnetic resonance imaging (MRI) system |
| CN108627783B (en) * | 2017-03-23 | 2022-01-14 | 通用电气公司 | Radio frequency coil array and magnetic resonance imaging transmitting array |
| CN106950520B (en) * | 2017-05-20 | 2020-06-26 | 深圳市金石医疗科技有限公司 | Self-generating and self-receiving birdcage array coil and control circuit thereof |
| CN108680882B (en) * | 2018-06-28 | 2019-08-27 | 深圳先进技术研究院 | A kind of double-core coil device and double-core radio frequency array lines coil apparatus |
| EP3825710A1 (en) * | 2019-11-19 | 2021-05-26 | Koninklijke Philips N.V. | Magnetic resonance volume coil with multiple independent transmit receive channels |
| CN112702078A (en) * | 2020-12-28 | 2021-04-23 | 电子科技大学 | Eight-channel MR-EPT phased array radio frequency coil input radio frequency signal program control system |
| CN214252552U (en) * | 2020-12-29 | 2021-09-21 | 深圳市联影高端医疗装备创新研究院 | Ultrahigh field emission shimming coil structure |
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| WO2023092673A1 (en) | 2023-06-01 |
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