CN108241133A

CN108241133A - For the system and method for the common mode trap in MRI system

Info

Publication number: CN108241133A
Application number: CN201711452551.1A
Authority: CN
Inventors: V.塔拉奇拉; R.S.斯托尔蒙; F.J.L.罗布; L.J.范纳塔
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 2016-12-27
Filing date: 2017-12-27
Publication date: 2018-07-03
Anticipated expiration: 2037-12-27
Also published as: CN108241133B

Abstract

Provide the various method and systems of the common mode trap for magnetic resonance imaging (MRI) device.In one embodiment, common mode trap includes：First conductor and the second conductor, the length around center conductor are rewound, and first conductor and second conductor are radially spaced apart a distance with center conductor, and first and second conductor is fixed to the first side of center conductor；And third conductor and the 4th conductor, its length around center conductor is rewound, the third conductor and the 4th conductor are radially spaced apart the distance with center conductor, and the third conductor and the 4th conductor are fixed to the second side of the center conductor opposite with the first side.In this way, the density of the common mode trap conductor in common mode trap can be increased, thus increase the mutual inductance between common mode trap and center conductor.

Description

For the system and method for the common mode trap in MRI system

Cross reference to related applications

The application is entitled " the SYSTEMS AND METHODS FOR COMMON MODE submitted on May 27th, 2016 The part continuation application of the U.S. Patent Application No. 15/166,636 of TRAPS IN MRI SYSTEMS ".Above-mentioned application it is complete Portion's content is incorporated by herein for all purposes.

Technical field

The embodiment of the theme of this disclosure is related to magnetic resonance imaging (MRI), and more particularly relates to MRI The common mode trap of system.

Background technology

Magnetic resonance imaging (MRI) is a kind of medical imaging modalities, can be in the feelings without using X ray or other ionising radiations The image of inside of human body is formed under condition.MRI forms powerful, uniform magnetostatic field using superconducting magnet.When the one of human body or human body When part is placed in magnetic field, nuclear spin associated with the proton in tissue water becomes to polarize, wherein with these spin correlations The magnetic moment of connection becomes the direction alignment preferentially along magnetic field, leads to the small net tissue magnetization along the axis.MRI system is also wrapped It includes gradient coil, generates the smaller amplitude with quadrature-axis, spatially changing magnetic field, with each by the body Position forms signature resonant frequency to be spatially encoded to MR signals.Then radio frequency (RF) coil is used in the resonance frequency of proton At rate or it nearby generates RF energy pulse, this increases energy for nuclear spin system.When Nuclear Spin Relaxation returns to its rest energy During amount state, they discharge the energy absorbed in the form of RF signals.The signal is detected by MRI system, and uses computer Image is converted into known algorithm for reconstructing.

As described above, send RF pumping signals using RF coils in MRI system and receive MR signals, i.e., by into The RF signals emitted as object.Loop transfer cable transmits letter between can be used in terms of other of RF coils and processing system Number, such as to control RF coils and/or receive information from RF coils.Loop transfer cable can be arranged in the hole of MRI system And it is subjected to the electromagnetic field for being generated and being used by MRI systems.The cable can support the common mode current that transmitter drives, the electric current The field distortion of generating means and/or uncertain heating.These field distortion may cause the shade of cable to appear in from reception In the image of MR signal reconstructions arrived.

In general, transmitter driving electricity can be mitigated using the balance converter or common mode trap that provide high common code impedance The influence of stream.However, common mode trap or obstruction circuit placement may be difficult in position, because appropriate puts Put can the positioning based on cable associated with common mode trap or coil and change.In addition, even if conventional common mode is fallen into Wave device or obstruction circuit are placed in position, it is also possible to excessive voltage and/or power dissipation occur.

Further, since fringe magnetic field, the balance converter (baluns) or common mode trap for leaning on too near each other on cable Device may become to couple, and so as to cause the detuning of balance converter, this may negatively affect the function of balance converter.

Invention content

In one embodiment, it is a kind of to include for the common mode trap of magnetic resonance imaging (MRI) device：First conductor and Second conductor, the length around center conductor are rewound, wherein, the first and second conductors and center conductor are radially spaced apart the One distance, wherein, the first and second conductors are fixed to the first side of center conductor；And third conductor and the 4th conductor, it encloses Length around center conductor is rewound, wherein, the third and fourth conductor is radially spaced apart the first distance, and its with center conductor In, the third and fourth conductor is fixed to the second side of the center conductor opposite with the first side.In this way, common mode trap can be increased In common mode trap conductor density, thus increase the mutual inductance between common mode trap and the center conductor that is disposed therein.

Specifically, the technical solution 1 of the application is related to a kind of common mode trap for being used for magnetic resonance imaging (MRI) device, Including：First conductor and the second conductor, first conductor and second conductor are rewound around the length of center conductor, In, first and second conductor is radially spaced apart the first distance with the center conductor, wherein, described first and second lead Body is fixed to the first side of the center conductor；And third conductor and the 4th conductor, the third conductor and the described 4th are led Body is rewound around the length of the center conductor, wherein, between third and fourth conductor and the center conductor radial direction First distance is separated, and wherein, third and fourth conductor is fixed to the center opposite with first side The second side of conductor.

2 common mode trap according to technical solution 1 of technical solution of the application, wherein, described first and second lead Body orthogonally crossedpath.

3 common mode trap according to technical solution 1 of technical solution of the application is further included along the length radially Ground surrounds the dielectric spacer of center conductor setting, wherein, the first, second, third and fourth conductor surrounds institute State dielectric spacer back-roll.

4 common mode trap according to technical solution 1 of technical solution of the application, further includes：First and second capacitances Device, first and second capacitor are positioned in every at one end of the length along first side；And third and 4th capacitor, third and fourth capacitor are positioned in every at one end of the length along the second side, In, first and second conductor is fixed to first and second capacitor, and wherein, third and fourth conductor is consolidated Surely third and fourth capacitor is arrived.

Common mode trap of the technical solution 5 of the application according to technical solution 4, further includes：

5th conductor and the 6th conductor, the 5th conductor and the 6th conductor surround the length of the center conductor Degree back-roll, wherein, the 5th conductor and the 6th conductor are radially spaced apart with the center conductor more than described first The second distance of distance, wherein, first and second conductor is fixed to the institute on first side of the center conductor State the first capacitor and second capacitor；And

7th conductor and the 8th conductor, the 7th conductor and the 8th conductor surround the length of the center conductor Degree back-roll, wherein, the 7th and the 8th conductor is radially spaced apart the second distance, and its with the center conductor In, the 7th and the 8th conductor is fixed to the third capacitor in the second side of the center conductor and described 4th capacitor.

Common mode trap of the technical solution 6 of the application according to technical solution 4, further includes：5th and the 6th capacitance Device, the 5th and the 6th capacitor is along the third side positioning equidistant with the first and second sides in each of the length At end；And the 7th and the 8th capacitor, the 7th and the 8th capacitor along relatively positioned with the third side and with The 4th equidistant side positioning of the first and second sides is in every at one end of the length.

Common mode trap of the technical solution 7 of the application according to technical solution 6, further includes：

5th conductor and the 6th conductor, the 5th conductor and the 6th conductor surround the length of the center conductor Degree back-roll, wherein, the 5th conductor and the 6th conductor are radially spaced apart first distance with the center conductor, Wherein, the 5th and the 6th conductor is fixed to the 5th capacitor on the third side of the center conductor and institute State the 6th capacitor；And the 7th conductor and the 8th conductor, the 7th conductor and the 8th conductor led around the center The length back-roll of body, wherein, the 7th and the 8th conductor and the center conductor be radially spaced apart described first away from From, and wherein, the 7th and the 8th conductor is fixed to the 7th electricity on the 4th side of the center conductor Container and the 8th capacitor.

8 common mode trap according to technical solution 1 of technical solution of the application, wherein, the common mode trap quilt It is tuned as providing the resonant frequency close to the working frequency of the MRI system.

9 common mode trap according to technical solution 1 of technical solution of the application further includes and surrounds institute with aturegularaintervals State center conductor setting multiple annular disks, wherein, in the conductor each pass through the multiple annular disk in it is each Annular disk.

The technical solution 10 of the application is related to a kind of common mode trap component for being used for magnetic resonance imaging (MRI) system, packet It includes：Center conductor with length and is configured to transmit between the MRI radio-frequency coils and processing element of the MRI system Signal；And multiple common mode traps, at least part along the length of the center conductor extend, the common mode Trapper is configured to provide impedance to reduce the transmitter driving current of the MRI system, wherein, in the common mode trap Each include the second length and including multiple conductors pair, each conductor of the multiple pairs of conductors is to including surrounding institute State the first conductor and the second conductor of center conductor back-roll.

Common mode trap component of the technical solution 11 of the application according to technical solution 10, wherein, the common mode is fallen into Each in wave device includes more than first a capacitors being located at the first end of the common mode trap and is located in described More than second a capacitors at the second end of common mode trap, wherein, first and second common mode of the common mode trap Trapper conductor is fixed to more than described first a capacitors and more than second a capacitor.

Common mode trap component of the technical solution 12 of the application according to technical solution 10, wherein, for described more Each conductor pair of a pairs of conductors, first conductor and second conductor orthogonally crossedpath.

Common mode trap component of the technical solution 13 of the application according to technical solution 10, wherein, it is the multiple common Each in mould trapper is adjacently set.

Common mode trap component of the technical solution 14 of the application according to technical solution 10, wherein, the common mode is fallen into Each in wave device includes the dielectric spacer radially set around the center conductor.

The technical solution 15 of the application is related to a kind of radio frequency (RF) coil for for magnetic resonance imaging (MRI) system and carries For the method for transmission cable, including：Center conductor is provided, the center conductor has length and is configured in the MRI systems Signal is transmitted between the RF coils and processing element of system；And at least part of the length along the center conductor Multiple common mode trap conductors pair are positioned around the center conductor, wherein, the multiple common mode trap conductor is to surrounding It is symmetrical to state center conductor, wherein, each common mode trap conductor is to including the first common mode trap conductor and the second common mode Trapper conductor, the first common mode trap conductor is along the part of the length of the center conductor around described Spiral winding, the second common mode trap conductor surround center conductor along the part of the length in a first direction Center conductor spiral winding in second direction opposite to the first direction.

The technical solution 16 of the application is related to according to the method described in technical solution 15, wherein, the multiple common mode trap The first the half of device pairs of conductors are positioned in the first radial distance of central axis away from the center conductor, and wherein, institute It states the second the half of multiple common mode trap pairs of conductors to be positioned in away from second radial distance of central axis, described second Radial distance is more than first radial distance.

The technical solution 17 of the application is related to according to the method described in technical solution 15, wherein, the first common mode trap Device conductor and the second common mode trap conductor are positioned at the midpoint of the length radially away from the center conductor The first distance of central axis at and the length every at one end radially away from the central axis second distance at, The second distance is less than first distance.

The technical solution 18 of the application is related to according to the method described in technical solution 15, wherein, the first common mode trap Device conductor and the second common mode trap conductor are located in the column at the first and second ends of the length.

The technical solution 19 of the application is related to, according to the method described in technical solution 15, further including：Along the center conductor The length dielectric spacer is radially provided；And the multiple common mode trap conductor is situated between to being connected to the electricity Matter spacer.

The technical solution 20 of the application is related to according to the method for claim 19, further including offer radially around institute State the shielding of dielectric spacer.

It is further described in detailed description it should be appreciated that offer is described briefly above in order to introduce in simplified form Series of concepts.Without the key or essential feature of the theme that intention assessment is claimed, the range of the theme is uniquely by detailed Claim after thin description limits.In addition, claimed theme is not limited to solve above or the disclosure any portion The implementation of any shortcoming pointed out in point.

Description of the drawings

Non-limiting example is read by referring to accompanying drawing to be described below, is better understood with the present invention, in attached drawing：

Fig. 1 is the block diagram of MRI system according to an embodiment of the invention.

Fig. 2 is the block diagram for showing continuous common mode trap component according to an embodiment of the invention.

Fig. 3 is perspective view of the tool there are two the common mode trap of common mode trap conductor.

Fig. 4 is that there are two the side views of the common mode trap of common mode trap conductor for tool on bending cable.

Fig. 5 is that there are two the side views of the common mode trap of common mode trap conductor for tool on straight line cable.

Fig. 6 is that there are two the vertical views of the common mode trap of common mode trap conductor for tool on straight line cable.

Fig. 7 is that there are four the common mode traps of common mode trap conductor for the tool according to an embodiment of the invention on straight line cable The perspective view of device.

Fig. 8 is the perspective view of the common mode trap on straight line cable with eight common mode trap conductors.

Fig. 9 is the perspective view of common mode trap according to an embodiment of the invention, is had on bending cable by washer Eight common mode trap conductors of support.

Figure 10 is that the common mode with eight common mode trap conductors according to an embodiment of the invention on straight line cable is fallen into The vertical view of wave device.

Figure 11 is the sectional view of the common mode trap of Figure 10 according to an embodiment of the invention.

Figure 12 is the section view of the common mode trap with 16 common mode trap conductors according to an embodiment of the invention Figure.

Figure 13 is to show the common mode trap according to an embodiment of the invention for tool there are four common mode trap conductor Exemplary method high level block diagram.

Figure 14 is to show the common mode trap according to an embodiment of the invention for being used to have eight common mode trap conductors Exemplary method high level block diagram.

Specific embodiment

The various embodiments for being related to the common mode trap for MRI system are described below.Specifically, system is provided use High density coiled arrangement in the common mode trap component of MRI system (such as the MRI system described in Fig. 1).Such as Fig. 2 institutes Show, the common mode trap component including multiple common mode traps can be placed on cable to transmit the MR data received.Figure 3-6 shows various views of the tool there are two the common mode trap of back-roll common mode trap conductor.In various embodiments, altogether Mould trapper can include more than two back-roll common mode trap conductor.For example, Fig. 7 shows that tool to be fallen into there are four common mode is rewound The common mode trap of wave device conductor.As another example, Fig. 8 shows that the common mode with eight back-roll common mode trap conductors is fallen into Wave device.Complexity with common mode trap configuration increases, and can mechanically be supported using various methods and common mode is kept to fall into The configuration of wave device conductor.For example, Fig. 9 shows multiple washers of support common mode trap conductor.Figure 10 and Figure 11 show use In another method that eight common mode trap conductors are arranged in common mode trap.Figure 12 is shown with 16 back-rolls altogether The common mode trap of mould trapper conductor.Figure 13 and Figure 14 shows the exemplary method for building high density common mode trap.

Fig. 1 shows magnetic resonance imaging (MRI) device 10, including magnetostatic field magnet unit 12, gradient coil unit 13, RF coil units 14, RF body coils unit 15, transmitting/reception (T/R) switch 20, RF port interfaces 21, RF actuator units 22nd, gradient coil drive unit 23, data acquisition unit 24, controller unit 25, sick bed 26, data processing unit 31, behaviour Make console unit 32 and display unit 33.Electromagnetic pulse signal is sent to by MRI device 10 to be placed on the quiet of formation Subject 16 in the imaging space 18 in magnetic field, to perform the scanning for obtaining magnetic resonance signal from subject 16, to be based on The image for rebuilding the slice of subject 16 by scanning the magnetic resonance signal so obtained.

Magnetostatic field magnet unit 12 generally includes the annular super conduction magnet for example in anchor ring vacuum tank.Magnet limits Surely the cylindrical space of subject 16 is surrounded, and constant primary magnetostatic field is generated along the Z directions of cylindrical space.

MRI device 10 further includes gradient coil unit 13, which forms gradient in imaging space 18 Magnetic field, to provide the magnetic resonance signal with three-dimensional localization information received by RF coil units 14.Gradient coil unit 13 wraps Three gradient coil systems are included, each gradient coil system generation favours the gradient of one of three spatial axis perpendicular to one another Magnetic field, and it is raw in each in frequency coding direction, phase-encoding direction and slice choice direction according to image-forming condition Into gradient fields.More specifically, gradient coil unit 13 applies gradient fields to select to cut in the slice choice direction of subject 16 Piece；And RF pulses are sent to the selected slice of subject 16 and encourage it by RF coil units 14.Gradient coil unit 13 is also Apply gradient fields on the phase-encoding direction of subject 16, with to come free RF pulse excitations slice magnetic resonance signal into Row phase code.Then, gradient coil unit 13 applies gradient fields on the frequency coding direction of subject 16, with to coming freely The magnetic resonance signal of the slice of RF pulse excitations carries out frequency coding.

RF coil units 14 are for example arranged to surround the region to be imaged of subject 16.By magnetostatic field magnet unit 12 form in the magnetostatic field space of magnetostatic field or imaging space 18, and RF coil units 14 are based on the control from controller unit 25 Signal is sent to subject 16 using as the RF pulses of electromagnetic wave, so as to generate high frequency magnetic field.This excitation subject's 16 treats into As the spin of the proton in slice.When the proton spin so encouraged in the slice to be imaged in subject 16 be back to initially When magnetization vector is aligned, RF coil units 14 receive the electromagnetic wave of generation as magnetic resonance signal.RF coil units 14 can make RF pulses are sent and received with identical RF coils.

RF body coils unit 15 be for example arranged to surround imaging space 18, and generate with by quiet in imaging space 18 The orthogonal RF magnetic field pulses of main field that field magnets unit 12 generates are to encourage core.With can easily be disconnected from MR devices 10 And the RF coil units 14 replaced with another RF coil unit are on the contrary, RF body coils unit 15 is in parallel by regularly attachment It is connected to MR devices 10.In addition, although such as the local coil of those including RF coil units 14 can be only to subject's 16 Regional area sends or receives signal from the region, but RF body coils unit 15 usually has larger overlay area, and It can be used for sending signal to the whole body of subject 16 or receive from it signal.Using only reception local coil and send body coil It provides uniform RF excitations and good image conformity, cost is deposited on the high RF power in subject's body.For hair Local coil is penetrated-receives, local coil provides RF excitations to interested region, and receives MR signals, thus reduces being stored in RF power in subject's body.It should be appreciated that the particular use of RF coil units 14 and/or RF body coils unit 15 depends on Imaging applications.

T/R switch 20 can selectively by RF body coils unit 15 when in the receiving mode operate when be electrically connected to data Collecting unit 24, and it is electrically connected to RF actuator units 22 when operation in the transmit mode.Similarly, T/R switches 20 can RF coil units 14 selectively are electrically connected to data acquisition unit when RF coil units 14 operate in the receiving mode 24, and it is electrically connected to RF actuator units 22 when operation in the transmit mode.When RF coil units 14 and RF body coil lists Both members 15 are in single sweep operation in use, for example, if RF coil units 14 are configured to receive MR signals and RF body lines Coil unit 15 is configured to send RF signals, then T/R switches 20 can guide the control signal from RF actuator units 22 It is guided to RF body coils unit 15, while by the MR signals received from RF coil units 14 to data acquisition unit 24.RF body lines The coil of coil unit 15 can be configured as to be operated with only emission mode, reception pattern or send-receive pattern.Part The coil of RF coil units 14 may be configured to send-receive pattern or only reception pattern is operated.

RF actuator units 22 include grid modulator (not shown), RF power amplifiers (not shown) and RF oscillators (not shown), for driving RF coil units 14 and forming high frequency magnetic field in imaging space 18.RF actuator units 22 are based on Control signal from controller unit 25 and using grid modulator by the RF signal modulations received from RF oscillators for have There is the signal of the predetermined timing of predetermined envelope.The RF signals modulated by grid modulator are amplified by RF power amplifiers, then defeated Go out to RF coil units 14.

Gradient coil drive unit 23 drives gradient coil unit 13 based on the control signal from controller unit 25, So as to generate gradient magnetic in imaging space 18.Gradient coil drive unit 23, which includes corresponding to, is included in gradient coil list The drive circuit (not shown) of three systems of three gradient coil systems in member 13.

Data acquisition unit 24 turns including preamplifier (not shown), phase detectors (not shown) and analog/digital Parallel operation (not shown), for acquiring the magnetic resonance signal received by RF coil units 14.In data acquisition unit 24, phase inspection The output for surveying device by the use of the RF oscillators from RF actuator units 22 is detected as with reference to signal phase from RF coil units 14 Receive and by preamplifier amplify magnetic resonance signal, and by the analog magnetic resonance signal after phase-detection be output to simulation/ Digital quantizer is to be converted into digital signal.The digital signal so obtained is output to data processing unit 31.

MRI device 10 includes the platform 26 for placing subject 16 on it.By based on from controller unit 25 Signal mobile station 26 is controlled, subject 16 can move inside and outside imaging space 18.

Controller unit 25 includes computer and record wants the recording medium of program performed by computer thereon.Program exists The various pieces of device is made to perform the operation for corresponding to predetermined scanning when being performed by computer.Recording medium can be included for example ROM, floppy disk, hard disk, CD, magneto-optic disk, CD-ROM or non-volatile memory card.Controller unit 25 is connected to operation and control Platform unit 32, and the operation signal for being input to operating console unit 32 is handled, and also by exporting control signal to it Come console 26, RF actuator units 22, gradient coil drive unit 23 and data acquisition unit 24.Controller unit 25 Data processing unit 31 and display unit 33 are also controlled to obtain based on the operation signal received from operating console unit 32 Required image.

Operating console unit 32 includes the user input equipment of such as keyboard and mouse.Operating console unit 32 is by grasping Author is set and to perform the region of imaging sequence using for example inputting the data for being such as imaged scheme.About imaging scheme The data that region is performed with imaging sequence are output to controller unit 25.

Data processing unit 31 include computer and recording medium, on the recording medium record to be performed by computer with into The program of the scheduled data processing of row.Data processing unit 31 is connected to controller unit 25, and is based on from controller unit The 25 control signals received perform data processing.Data processing unit 31 is also connected to data acquisition unit 24, and passes through Various image processing operations are applied to from the magnetic resonance signal that data acquisition unit 24 exports and generate frequency spectrum data.

Display unit 33 includes display equipment, and controls signal in display equipment based on what is received from controller unit 25 Image is shown on display screen.Display unit 33 shows that operator is about the cuit for example about the image of cuit From 32 input operand evidence of operating console unit.Display unit 33 also shows the subject 16 generated by data processing unit 31 Sectioning image.

Different RF coil units can be used for different scanning targets.For this purpose, RF coil units 14 can be filled with MRI It puts 10 to disconnect so that different RF coil units may be coupled to MRI devices 10.RF coil units 14 can be via even It connects device 17 and RF port interfaces 21 is connected to T/R switches 20, and be therefore connected to RF actuator units 22 and data acquisition unit 24.Specifically, connector 17 is inserted into RF port interfaces 21 RF coil units 14 being electrically coupled to T/R switches 20. It can realize the exchange of RF coil units easily using the single connector 17 for being fixedly attached to RF coil units 14.

It, can be using loop transfer cable (not shown) come at RF coils (for example, RF coil units 14) during scanning Signal is transmitted between other aspects (for example, data acquisition unit 24, controller unit 25 etc.) of processing system, such as with control RF coils processed and/or from RF coils receive information.Loop transfer cable can be arranged on the hole of MRI device 10 or imaging space 18 It is interior, and the electromagnetic field that is generated and use by MRI device 10 acts on.The cable can support the common mode electricity that transmitter drives Stream, the field distortion of the current-generating sections and/or uncertain heating.The balanced transformation that high common code impedance is provided can be utilized Device or common mode trap mitigate the influence of transmitter driving current.This common mode trap and common mode trap component it is various Embodiment further describes in the present specification.

Fig. 2 shows the schematic block diagrams of continuous common mode trap component 200 formed according to various embodiments.Common mode is fallen into Wave device assembly 200 may be configured to for example for being used in the hole of MRI system (such as MRI device 10 described above). For example, in the illustrated embodiment, common mode trap component 200 is configured as transmission cable 201, transmission cable 201 is configured to For transmitting signal between the processing unit of MRI systems (or controller) 250 and receiving coil 260.In diagram embodiment In, transmission cable 201 (or common mode trap component 200) including center conductor 210 and multiple common mode traps 212,214, 216.It is noted that although common mode trap 212,214 and 216 is portrayed as different from center conductor 210, at some In embodiment, common mode trap 212,214,216 can be integrally formed with center conductor 210 or centered on conductor 210 A part.

Center conductor 210 in the illustrated embodiment has length 204, and is configured to connect in the MRI of MRI systems Signal is transmitted between take-up circle 260 and at least one processor (for example, processing unit 250).Center conductor 210 can include example Such as one or more of tape conductor, line or coaxial cable bunch.The length 204 of discribed center conductor 210 is led from center The first end (it is connected to processing unit 250) of body 210 extend to center conductor 210 second end (its be connected to MRI reception Coil 260).In some embodiments, center conductor can be to pass through the central opening of common mode trap 212,214,216.

As shown in Fig. 2, (it is understood to be cooperation and is fallen into forming common mode discribed common mode trap 212,214,216 Wave device unit 218) extend along at least part of the length 204 of center conductor 210.In the illustrated embodiment, common mode trap Device 212,214,216 does not extend along whole length 204.However, in other embodiments, common mode trap 212,214,216 Can extend along whole length 204 or substantially along whole length 204 (for example, along whole length 204, in addition to It is set to except the part for the end for being for example connected to processor or receiving coil).Common mode trap 212,214,216 is adjacently Setting.As shown in Fig. 2, each in common mode trap 212,214,216 adjacently set common mode trap 212,214, In 216 at least another.As used in this specification, the adjacent portion for being construed as including close to or being in contact with each other Part or aspect.For example, adjacent component can be against each other.It is noted that in practice, it is in some embodiments, small Or inapparent gap can be between adjacent part.In some embodiments, inapparent gap (or conductor length) can be with It is understood to be less than 1/40 of the wavelength of tranmitting frequency in free space.In some embodiments, inapparent gap (or conductor Length) it is construed as 2 centimetres or smaller.For example, adjacent common mode trap do not have between the two (or without significant) this The gap between two parties of sample or conductor：It may easily be sensed by the electric current for carrying out self-magnetic field, without providing alleviation by common mode trap. For example, as depicted in fig. 1, common mode trap 212 is adjacent to common mode trap 214, and common mode trap 214 is adjacent to common mode and falls into Wave device 212 and common mode trap 216 (and being plugged between common mode trap 212 and common mode trap 216), and common mode Trapper 216 is adjacent to common mode trap 214.Each in common mode trap 212,214,216 is configured to provide impedance To reduce the transmitter driving current of MRI system.In various embodiments, common mode trap 212,214,216 provides high common mode Impedance.For example, each common mode trap 212,214,216 can include resonance circuit and/or one or more resonance sections, with Desired impedance is provided in expected frequency or nearby or in range of target frequencies.It is noted that those skilled in the art Common mode trap 212,214,216 and/or common mode trap unit 218 can be known as choke coil or balance converter.

With with have the spaced system of discrete common mode trap detached therebetween on the contrary, various embodiments (for example, Common mode trap component 200) there is the part that continuously and/or adjacently extends on it of common mode trap so that along this Part is not provided with the position of common mode trap.Therefore, it is possible to reduce or eliminate selection or realize common mode trap The difficulty of specific placement location, because interested all positions can be included in continuous and/or adjacent common mode trap In device.In various embodiments, continuous trapper part (for example, common mode trap unit 218) can be along transmission cable Length or length a part extension.Continuous trapper part by each common mode trap for adjacently engaging or can be fallen into Wave device section (for example, common mode trap 212,214,216) formation.In addition, adjacent be total to may be used in various embodiments Mould trapper come realize reduction and coil part interaction, by heat be distributed over a substantial area (for example, to prevent heat Point) or assist in ensuring that obstruction at least one of at positions that are desired or needing.It in addition, in various embodiments can be with Spread voltage over a substantial area is helped using adjacent common mode trap.In addition, in various embodiments, it is continuous and/ Or adjacent common mode trap provides flexibility.For example, in some embodiments, can use continuous length conductor (for example, Around the external conductor of center conductor winding) or the adjoining being integrally formed into section is otherwise organized to be fallen into form common mode Wave device.In various embodiments, one is provided using adjacent or continuous common mode trap (for example, being formed in cylinder) Determine the flexibility of range, by it, the flexure of component will not significantly change the resonant frequency of structure or component is bent at it When keep frequency.

It is noted that in various embodiments, each common mode trap or section (for example, common mode trap 212, 214th, 216) can generally similar to one anotherly it construct or formed (for example, each trapper can be tapered convolute coil A part for length), but each individually trapper or section may be configured to slightly have not with other trappers or section Together.For example, in some embodiments, each common mode trap 212,214,216 is independently tuned.Therefore, each common mode is fallen into Wave device 212,214,216 can have the resonant frequency of other common mode traps different from same common mode trap component 200.

Alternatively or additionally, each common mode trap can be tuned as with the working frequency close to MRI system Resonant frequency.As used in this specification, when resonant frequency limits or during corresponding to frequency band including working frequency or when resonance frequency The close enough working frequency of rate blocks (on-frequency blocking) or the offer at working frequency to provide in frequency During blocked impedance, common mode trap is construed as with the resonant frequency close to working frequency.

In addition, additionally or alternatively, each common mode trap can be tuned to the work less than MRI systems (or each common mode trap can be tuned to the resonance with the working frequency higher than MRI system to the resonant frequency of frequency Frequency).In each trapper, with the frequency less than operating frequency, (or each trapper has the frequency that is higher than working frequency Rate) in the case of, it can eliminate or reduce any trapper and cancel out each other (for example, since a trapper has higher than work The frequency of frequency, different trappers have less than working frequency frequency) risk.As another example, each common mode is fallen into Wave device can be tuned to special frequency band to provide broadband common mode trap component.

In various embodiments, common mode trap can have two dimension or the configuration of three-dimensional butterfly with offset magnetic field coupling and/ Or localized distortion.

Fig. 3 is perspective view of the tool there are two the common mode trap 300 of back-roll common mode trap conductor.Common mode trap 300 Including outer sleeve or shielding 303, dielectric spacer 304, inner sleeve 305, the first common mode trap conductor 307 and the Two common mode trap conductors 309.

First common mode trap conductor 307 is surrounded on 304 spiral winding of dielectric spacer or in a first direction 308 The spiral winding at away from the tapered distance of the center conductor (not shown) being arranged in the hole 318 of common mode trap 300.In addition, Second common mode trap conductor 309 is around 304 spiral winding of dielectric spacer or opposite with first direction 308 the On two directions 310 at away from the tapered distance of the center conductor being arranged in hole 318 spiral winding.In the illustrated embodiment, One direction 308 is clockwise, and second direction 310 is counterclockwise.

The conductor 307 and 309 of common mode trap 300 can include conductive material (for example, metal), and can be shaped For such as band, line and/or cable.In some embodiments, it rewinds conductor or external conductor 307 and 309 may be used as in The return path of the electric current of heart conductor.In addition, in various embodiments, back-roll conductor 307 and 309 can be orthogonally intersected with each other (for example, the center line or path orthogonal that are limited by the first common mode trap conductor 307 are in as common mode trap conductors cross road The center line limited by the second common mode trap conductor 309 of diameter or path), to eliminate, minimize or reduce common mode trap Connection between conductor.

It can be with it is further noted that in various embodiments, the first common mode trap conductor 307 and the second common mode be fallen into Wave device conductor 309 is loosely wrapped in around dielectric spacer 304, to be provided when common mode trap 300 is bent or bends Variation in flexibility and/or any combination of reduction, connection or inductance.It is noted that it rewinds the pine of external conductor or tightly may be used To vary depending on the application (for example, the bending needed for relative size, common mode trap based on conductor and dielectric spacer Or deflection etc.).In general, external or reversed coiled conductor should be tight enough so that they keep around dielectric spacer 304 Be generally oriented in identical, but enough pine with allow enough relaxations during common mode trap 300 is bent or bends or Amount of movement, to avoid, minimize or reduce back-roll external conductor connection or combination.

In the illustrated embodiment, exterior shield 303 is discontinuous in the centre of common mode trap 300, is situated between with exposure electricity A part for matter spacer 304, in some embodiments, dielectric spacer 304 are set along the whole length of common mode trap 300 It puts.As non-limiting example, dielectric spacer 304 can be made of teflon or another dielectric material.Dielectric every It is used as capacitor, therefore can be tuned or be configured to provide desired resonance from object 304.It should be appreciated that for being fallen into common mode The other configurations that wave device 300 provides capacitance are that possible and shown configuration is exemplary and not limiting.Example Such as, alternatively discrete capacitor can be set to common mode trap 300.

In addition, common mode trap 300 includes being fixed to the first common mode trap conductor 307 and the second common mode trap conductor 309 the first column 313 and the second column (not shown).For this purpose, the first column 313 and the second column are positioned in the phase of common mode trap Opposite end, and fixed to exterior shield 303.First column 313 and the second column ensure the first common mode trap conductor 307 and the second common mode Trapper conductor 309 is positioned in the end of common mode trap 300 close to exterior shield 303, thus provide as this specification into The tapered butterfly configuration of the back-roll conductor of one step description.

Tapered butterfly configuration includes the first loop formed by the first common mode trap conductor 307 and by the second common mode trap The second loop that device conductor 309 is formed, the sensing electric current being arranged so that in the first loop 307 (due to the electric current of magnetic field induction) It cancels out each other with the sensing electric current in the second loop 309.For example, if field is uniform and the first loop 307 and the second ring Road 309 has equal area, then the net current of gained will be zero.The tapered cylindrical arrangement of loop 307 and 309 is relative to logical The two-dimensional arrangement for being usually used in common mode trap provides the consistency of improved flexibility and resonant frequency during flexure.

In general, tapered butterfly configuration can be used to refer to the conductor configuration of magnetic flux elimination, example as used in this specification Such as include at least two similarly sized opposite loops, the loop is set, and cloth around at least one axisymmetrical It is set to so that being tended to cancel out by the electric current that magnetic field senses in each loop (or one group of loop) at least one other loop The electric current sensed in (or one group of loop).For example, referring to Fig. 2, in some embodiments, back-roll conductor is (for example, around center structure The conductor that part and/or axis are wound in the opposite hand of spiral) certain distance can be radially spaced apart with center conductor 210 To form common mode trap 212,214,216.It further describes as depicted in fig. 3 and in the present specification, radial distance can With tapered to reduce or completely eliminate edge effect towards the end of common mode trap.In this way, common mode trap 212,214,216 It can continuously or adjacently position and therebetween without significant gap.

Fig. 4 is the common mode trap according to an embodiment of the present disclosure (bent) in bending on cable or center conductor 401 side view 400.As depicted, common mode trap 401 includes winding around cable or center conductor (not shown) outer Parts casing pipe or shielding 403.As depicted, common mode trap 401 includes the first common mode trap conductor 407 and the second common mode is fallen into Wave device conductor 409, the first common mode trap conductor 407 and the second common mode trap conductor 409 are both secured to and are respectively positioned at The first column 413 and the second column 415 at the first end and second end of common mode trap 401.First common mode trap conductor, 407 He Second common mode trap conductor 409 is rewound around casing or shielding 403 with tapered coiled arrangement.Tapered coiled arrangement is in this theory It is further described in bright book with reference to Fig. 5-6.

In some embodiments, as described above, it is discontinuous to shield 403 in the centre of common mode trap 401, with exposure The dielectric spacer 420 that can be arranged on along the length of common mode trap 401 in shielding 403.It is it will be appreciated, however, that electric The different configurations of dielectric spacers are possible, and discribed configuration is exemplary and not limiting.

Fig. 5 is the common mode trap according to an embodiment of the present disclosure on straight line (i.e. non-deflected) cable or center conductor 401 side view 500.Common mode trap 401 has length L.

About tapered coiled arrangement, it should be noted that the first common mode trap conductor 407 and the second common mode trap conductor 409 are opened from the central axis 530 of common mode trap 401 with different radial distance or vertical separation.Particularly, the first common mode is fallen into Wave device conductor 407 and the second common mode trap conductor 409 be spaced apart at column 413 and 415 with central axis 530 radial distance or Height H1.When the first common mode trap conductor 407 and the second common mode trap conductor 409 are wrapped in 403 surrounding of shielding, conductor The orthogonal crossover at the radial distance H2 with central axis 530.In addition, in the centre of common mode trap 401 (that is, in dielectric The near gaps that spacer 420 exposes), the first common mode trap 407 and the second common mode trap 409 with central axis 530 Radial distance H3 at orthogonal crossover.

Height H1 may be configured so that 409 quilt of the first common mode trap conductor 407 and the second common mode trap conductor It is located at shielding 403 or substantially close to shielding 403, and height H3 may be configured so that the first common mode trap is led 407 and second common mode trap conductor 409 of body is positioned at the desired distance far from shielding 403, and herein, conductor is in common mode The intermediate quadrature of trapper 401 intersects.That is, height H3 is noticeably greater than height H1.

In addition, the height of the first common mode trap conductor 407 and the second common mode trap conductor 409 at their orthogonal crossovers Radial distance H1 can be more than and less than radial distance H3 by spending H2.In this way, the spiral of the first and second common mode trap conductors is matched It puts tapered towards the end of common mode trap.However, in some instances, height H2 and height H3 can be equal so that The taper ratio height H2 of spiral between the orthogonal crossover of conductor 407 and 409 at height H2 and column 413 and 415 is less than height It spends steeper during H3.It is such configuration may be it is desired because the impedance of common mode trap 401 in common mode trap conductor more It is maximum during far from 403 interval of shielding.It will be appreciated, however, that height H1, H2 and H3 may be configured to obtain common mode trap 401 desired impedance, while reduce or eliminate the edge effect of the end of common mode trap 401.

In addition, the eccentric crosspoint of two of conductor is all shown at identical radial distance H2 so that spiral Central symmetry of the taper about common mode trap.However, in some embodiments, eccentric crosspoint can be positioned in from center The different radial distance of axis so that the taper of spiral is asymmetric.

Spiral of the spiral topology of common mode trap based on two reverse rotations.First spiral can be wrapped according to the following formula Around common mode trap：

Wherein,Represent azimuthLocate the radius of spiral.Similarly, the second spiral can be wrapped according to the following formula Around common mode trap：

According to the orthogonality condition of two spirals, in order to realize the minimum mutual inductance between spiral, the length L of common mode trap Relationship between its maximum radius is：

If functionIt is constant value along entire common mode trap length L, such as R_max, then common mode trap Topology corresponds to previous common mode trap method.

In addition, functionIt can be with selected as symmetric function.For example, functionIt can be about in common mode trap The heart is symmetrical, along common mode trap length L in least radius R_minWith maximum radius R_maxBetween built-in conical by its shape be defined For：

Wherein,It is at maximum radius at (for example, at the center for the common mode trap intersected in spiral) including spiral Azimuth, and wherein n includes the exponent number of taper.As n is from 0 increase, the taper of spiral towards the end of common mode trap becomes It is steeper.Therefore, in the design of common mode trap, the value of the taper exponent number n of selection can be adjusted, selectively to control edge , so as to increase the quantity of the common mode trap of the cable of per unit length or center conductor.This specification combination Fig. 5 is further Exemplary common mode trap of the description with different taper exponent number n is configured.

Fig. 6 is the vertical view of the common mode trap 401 on straight line cable or center conductor according to an embodiment of the present disclosure 600.The tapered coiled arrangement of first common mode trap conductor 407 and the second common mode trap conductor 409 is in the first common mode trap It is apparent in radial distance H4, H5, H6 and H7 of the variation of 407 and second common mode trap conductor 409 of device conductor.

Closer at column 413, the first common mode trap conductor 407 and the second common mode trap conductor 409 are fallen into common mode The central axis 530 of wave device 401 is spaced apart radial distance H4.Meanwhile it is more leaned near the expose portion of dielectric spacer 420 At the orthogonal crossover point of nearly conductor 407 and 409, the first conductor 407 and the second conductor 409 and the central shaft of common mode trap 401 Line 530 is spaced radial distance H5.In some embodiments, radial distance H4 is less than radial distance H5.In this way, the first conductor 407 It is tapered towards column 413 with the coiled arrangement of the second conductor 409.

Similarly, towards column 415, the first and second conductors are spaced apart radial distance H7 with central axis 530, and are more leaning on At nearly central intersection point, conductor is spaced apart radial distance H6 with central axis 530.Radial distance H6 can be more than radial distance H7, so as to make the spiral-shaped tapered towards column 415 of the first conductor 407 and the second conductor 409.

In some embodiments, radial distance H4 and H7 are equal, and radial distance H5 and H6 is equal.In this way, conductor Taper can be about the intermediate symmetry of common mode trap 401.However, in other embodiments, radial distance can be by differently Configuration so that the taper of spiral is asymmetric.

Fig. 7 is that there are four common mode traps for the tool according to an embodiment of the invention on straight line cable or center conductor 702 The perspective view 700 of the common mode trap 701 of conductor.Specifically, common mode trap 701 include common mode trap conductor 710,711, 712 and 713.Similar to the common mode trap described above in association with Fig. 3-6, common mode trap 701 can be included at least partly Surround the shielding 703 of center conductor 702 and dielectric spacer 704, dielectric spacer 704 in some instances can be as It is discribed partially exposed like that.

As depicted, common mode trap conductor is configured in the back-roll centering of common mode trap conductor.For example, common mode is fallen into Wave device conductor 710 and 711 terminates at point 716 and 718, and is rewound with coiled arrangement so that common mode trap conductor 711 encloses It is wound in the clockwise direction around center conductor 702, and common mode trap conductor 710 surrounds center conductor 702 in side counterclockwise Winding upwards.The first common mode trap conductor is consequently formed to 715 in a pair of of common mode trap conductor 710 and 711.First common mode is fallen into Wave device conductor is therefore similar with a pair of of common mode trap conductor 407 and 409 of above-mentioned common mode trap 401 to 715 and rises similar Effect.For example, orthogonal crossover is three times in the coiled arrangement of description for common mode trap conductor 710 and 711.

Similarly, common mode trap conductor 712 and 713 terminates at point 717 and 719, and is rewound with coiled arrangement so that Common mode trap conductor 712 is wound in the clockwise direction around center conductor 702, and during common mode trap conductor 713 surrounds Heart conductor 702 is wound in the counterclockwise direction.The second common mode trap is consequently formed in a pair of of common mode trap conductor 712 and 713 Conductor is to 720.

Second common mode trap conductor can be similar to the first common mode trap conductor to 720 to 715, the difference lies in It is reversed in position with the first common mode trap conductor to 715.For this purpose, terminal 716 and 718 be positioned in center conductor 703 with On 717 and 719 opposite side of terminal.

It should be noted that common mode trap 701 can have identical length L with common mode trap 401 described above.This Sample, the quantity (density that common mode trap is also referred to as in this specification) of the common mode trap conductor of common mode trap device 701 are Twice of the density of above-mentioned common mode trap device 401.In other words, the density of common mode trap 701 is relative to common mode trap 401 density increases.By increasing the density of common mode trap, common mode trap 701 and the mutual inductance of center conductor 702 increase. Specifically, during the mutual inductance between common mode trap 701 and center conductor 702 is common mode trap 401 and is disposed therein Twice of mutual inductance between heart conductor.Then, common mode trap 701 provides higher impedance on center conductor 702, so as to change Kind center conductor 702 is to the invisibility of external electromagnetic radiation.

As depicted, common mode trap is connected to 715 and 720 on the surface of center conductor 702, and center conductor 702 can To be enclosed in the dielectric spacer 704 that conductor 801 provides capacitance.Wherein common mode trap conductor is symmetrically rewound and straight The flutter of connection can be referred to as in the present specification by being connected to this configuration for the dielectric spacer for surrounding center conductor in succession Balance converter.The specification also describes other configurations, such as floating flutter balance converter, wherein common mode trap to lead Body is connected to capacitor or dielectric substance far from center conductor positioning.

Fig. 8 is the common mode trap 801 for having on straight line cable or center conductor 802 eight common mode trap conductors Perspective view 800.Specifically, common mode trap 801 includes 810,811,812,813,820,821,822 and of common mode trap conductor 823。

Similar to above-mentioned common mode trap 701,810,811,812,813,820,821,822 and of common mode trap conductor 823 are configured in couples.Specifically, common mode trap conductor 810 and 811 is rewound with above-mentioned coiled arrangement, so as to form One common mode trap conductor is to 816, and common mode trap conductor 812 and 813 is similarly rewound with coiled arrangement and forms second Common mode trap conductor is to 817.As depicted, the first common mode trap conductor is positioned in 816 far from center conductor 802 The first radial distance of central axis 807 at, and the second common mode trap conductor is positioned in 817 far from center conductor 802 The second radial distance of central axis 808 at, wherein the first radial distance 807 be more than the second radial distance 808.

Similarly, common mode trap conductor 820 and 821 is rewound with coiled arrangement, is led so as to form third common mode trap Body is to 826, and common mode trap conductor 822 and 823 is rewound with coiled arrangement, so as to form the 4th common mode trap conductor pair 827.Third common mode trap conductor is positioned in the first radial distance of central axis 807 far from center conductor 802 to 826 Place, and the 4th common mode trap conductor is positioned in the second radial distance of central axis 808 far from center conductor 802 to 827 Place.

Therefore four common mode trap conductors pair that common mode trap 801 is symmetrically arranged including surrounding center conductor 802. Therefore the density of common mode trap 801 is twice of the density of above-mentioned common mode trap 701.

Common mode trap conductor terminates at 816 and 817 in first capacitor of the opposite end for being located in common mode trap 801 814 and second at capacitor 815.Similarly, common mode trap conductor terminates at 826 and 827 and is located in common mode trap At 824 and the 4th capacitor 825 of third capacitor of 801 opposite end.As depicted, the first capacitor 814 and the second electricity Container 815 is positioned on the both sides opposite with 824 and the 4th capacitor 825 of third capacitor of center conductor 802.

Various methods of the common mode trap conductor support in common mode trap are available by being used for described in this specification 's.For example, Fig. 9 is the perspective of the common mode trap 901 with eight common mode trap conductors according to an embodiment of the invention Figure 90 0, eight common mode trap conductors are by 910 machine of multiple annular disks on straight line cable or center conductor 902 or washer Support to tool.Common mode trap 901 can be similar to common mode trap 801, because common mode trap 901 can include four altogether Mould trapper conductor is positioned in far from center conductor (being portrayed as dotted line), wherein the two of common mode trap pairs of conductors First radial distance of 902 central axis, and remaining two common mode trap conductor is led to being positioned in far from center Second smaller radial of the central axis of body 902 is at distance.

Multiple washers 910 include the first washer 911, second packing ring 912, third washer 913, the 4th washer the 914, the 5th pad Enclose the 915, the 6th washer 916, the 7th washer 917, the 8th washer 918 and the 9th washer 919.As depicted, multiple washers 910 can be distributed uniformly and regularly along common mode trap 901.As illustrative and unrestricted example, multiple pads Each washer in circle 910 can include the annular disk being molded of plastic material.

In addition, each washer includes multiple conductor apertures, common mode trap conductor can be to pass through these conductor apertures.In order to Illustrate, Fig. 9 further includes the front view 930 of the exemplary washer 931 with inside radius 932 and outer radius 933.Washer 931 limits Hole 934, center conductor can be set to pass through the hole 934.In addition, washer 931 includes multiple conductor apertures, common mode trap is led Body can be to pass through these conductor apertures.Specifically, washer 931 include first pair of 935, second pairs of conductor aperture conductor aperture 936, Third is to conductor aperture 937 and the 4th pair of conductor aperture 938.

As depicted, first pair of conductor aperture 935 and the 4th pair of conductor aperture 938 can relatively be positioned adjacent to by The outer edge for the washer 931 that outer radius 933 limits, and second pair of conductor aperture 936 and third can be opposite to conductor aperture 937 Ground is located near the inward flange of washer 931 limited by inside radius 932.Reference is led above in association with common mode trap described in Fig. 8 Body pair, the common mode trap conductor at the first radial distance 807 can be to pass through 935 He of outer conductor aperture to 816 and 826 938.Similarly, the common mode trap conductor at the second radial distance 808 can be to pass through inner wire aperture to 817 and 827 936 and 937.

Each washer in multiple washers 910 can be rotated by 90 ° relative to each adjacent washer.For example, washer 911 To be arbitrarily defined as the orientation positions of zero degree in the end of common mode trap 901.Meanwhile washer 912 is relative to washer 911 It is rotated by 90 ° so that the conductor aperture of washer 912 is oriented 90 degree relative to the conductor aperture of washer 911.In addition, washer 913 It being rotated by 90 ° relative to washer 912 so that the conductor aperture of washer 913 is oriented 90 degree relative to the conductor aperture of washer 912, But relative to the conductor aperture of washer 911 into zero degree.Rotation configuration is repeated for each washer in multiple washers 910, is made It obtains washer 911,913,915,917 and 919 and is orientated alignment each other, and washer 912,914,916 and 918 is orientated alignment each other.Often Conductor bores are configured to force to make the common mode trap conductor orthogonal crossover passed through.In this way, common mode trap can be kept The symmetry of device configuration, and validity of the common mode trap in terms of external electromagnetic radiation is fought therefore is kept, while still The flexibility of common mode trap on center conductor is provided.

In some instances, the floating capacitor of all capacitors 814,815,824 and 825 as explained above with Fig. 8 descriptions (not shown) can be embedded in the washer 911 and 919 of the end of common mode trap 901.In other examples, common mode Trapper 901 can include the flutter balance converter of connection so that common mode trap conductor is connected to cladding center conductor 802 Dielectric spacer (not shown).Such example is illustrative and be not restrictive, it should be understood that can be utilized and is used for Any suitable configuration of capacitance is provided to common mode trap 901.

The configuration (configuration in the conductor aperture of quantity and each washer including washer) of multiple washers can depend on altogether The concrete configuration of mould trapper.For example, multiple washers 910 of common mode trap 901 are configured as supporting common mode trap conductor Non-tapered helical design, two of which common mode trap conductor is to being positioned on two opposite sides of common mode trap not Same radial distance.However, in some instances, common mode trap conductor is differently distributed to that can surround center conductor.Example It such as, can be with to four identical additional common mode trap conductors pair with four common mode trap conductors describing in Fig. 7 and Fig. 8 It is positioned in common mode trap, and relative to the four common mode trap conductors described in Fig. 7 and Fig. 8 to being oriented 90 degree, So that common mode trap include 16 common mode trap conductors (the first radial distance eight common mode trap conductors and Eight common mode trap conductors of the second radial distance).Therefore, each washer can include suitably be distributed eight it is additional Conductor aperture is to accommodate additional common mode trap conductor pair.

Further, in some instances, as explained above with described in Fig. 5 and Fig. 6, common mode trap conductor can be towards altogether The end of mould trapper is tapered.In such an example, the inside radius and outer radius of one or more of multiple washers washer It can adjust to adapt to common mode trap conductor being gradually reduced along the radial distance of common mode trap length.

For mechanical support or formed common mode trap conductor another method be by common mode trap conductor and Corresponding floating capacitor in some examples is integrated in the ideally hose of the similar PVC comprising teflon.Center conductor Or cable can be easily positioned in hose to provide common mode trap to center conductor.Hose can be flexible, to permit Perhaps function of the flexural center conductor without interfering common mode trap.Another method for forming common mode trap conductor is by conducting wire Around the casing braiding that can be placed on center conductor.Another method, which can include providing, is connected to common mode trap conductor connection The column for the shielding being connected to, as explained above with described in Fig. 4-6.

Figure 10 show it is according to an embodiment of the invention on straight line cable or center conductor 1002 have eight common modes The vertical view 1000 of the common mode trap 1001 of trapper conductor.Figure 11 shows the common mode trap according to one embodiment The sectional view 1100 of 1001 one end.

Common mode trap 1001 includes being located in four columns of each end of common mode trap 1001.Such as in sectional view It is discribed in 1100, for example, column 1010,1020,1030 and 1040 is regularly distributed over around the circumference of center conductor 1002 At the first end of common mode trap 1001；Similarly, column 1011,1021 and of column 1010,1020 and 1030 are corresponded respectively to 1031 and the 8th column (not shown) corresponding to column 1040 be regularly distributed over common mode around the circumference of center conductor 1002 and fall into It is such as discribed in vertical view 1000 at second opposite end of wave device 1001.

Two common mode trap conductors are fixed to each column of common mode trap 1001.For example, the first common mode trap is led 1012 and second common mode trap conductor 1013 of body surrounds center conductor 1002 spirally along the length of common mode trap 1001 Fixed to the first column 1010, and fixed to the second column 1011.Third common mode trap conductor 1022 and the 4th common mode trap Conductor 1023 surrounds 1002 spiral shell of center conductor at the first end of common mode trap 1001 along the length of common mode trap 1001 Rotation ground is fixed to third column 1020, and the 4th column 1021 is fixed at the second opposite end of common mode trap 1001, such as institute Describe.5th common mode trap conductor 1032 and the 6th common mode trap conductor 1033 are fixed to the 5th column at first end 1030, and the 6th column 1031 is fixed at second end.7th common mode trap conductor 1042 and the 8th common mode trap conductor 1043 are fixed to the 7th column 1040, and the 8th column is fixed at second end.As described above with describe in Figure 10, per a pair of Common mode trap conductor is rewound with coiled arrangement.In addition, in some instances, common mode trap conductor can towards first end and Second end is tapered, but it is to be understood that in other examples, common mode trap conductor can be in the entire of common mode trap 1001 The constant radial distance of the central axis away from center conductor 1002 is kept in length.

In some instances, the density of common mode trap can increase relative to the density of above-described common mode trap Add.For example, Figure 12 shows the 16 common mode trap conductors on center conductor 1202 of having according to one embodiment The sectional view 1200 of one end of common mode trap 1201.Similar to above-mentioned common mode trap 801 and 901, common mode trap 1201 Multiple common mode trap conductors pair including being connected to the capacitor for being in configuration of floating.However, with common mode trap 801 and 901 compare, and common mode trap 1201 includes two additional capacitors in every one end of common mode trap, these capacitors surround The circumference of common mode trap is regularly distributed, similar to the distribution of the column of common mode trap 1001.Common mode trap 1201 because This includes eight capacitors, including the first capacitor 1210, the second capacitor 1220,1230 and the 4th capacitor of third capacitor 1240 and the correspondence capacitor (not shown) at the opposite end (not shown) of common mode trap 1201.

As depicted, two pairs of common mode trap conductors are fixed to each capacitor, are included in away from center conductor 1202 The first radial distance of central axis the first common mode trap conductor pair and in the central axis away from center conductor 1,202 Second common mode trap conductor pair of two radial distances, wherein the first and second radial distances are different.For example, first is common Mould trapper conductor 1212 be fixed to the first capacitor 1210, and along common mode trap 1201 length first radially Around 1202 clock wise spirals of center conductor at distance, and the second common mode trap conductor 1213 is fixed to the first capacitor 1210, and along the length of common mode trap 1,201 1202 counter-clockwise helical of center conductor is surrounded in the first radial distance. The first common mode trap conductor pair is consequently formed in first common mode trap conductor 1212 and the second common mode trap conductor 1213.Together When, third common mode trap conductor 1214 is fixed to the first capacitor 1210, and exists along the length of common mode trap 1201 The second radial distance more than the first radial distance surrounds 1202 clock wise spirals of center conductor, and the 4th common mode trap is led Body 1215 be fixed to the first capacitor 1210, and along common mode trap 1201 length in the second radial distance surrounds 1202 counter-clockwise helical of heart conductor.1214 and the 4th common mode trap conductor 1215 of third common mode trap conductor is consequently formed Two common mode trap conductors pair.

Similarly, the 5th common mode trap conductor 1222 and the 6th common mode trap conductor 1223 are fixed to the second capacitor 1220, third common mode trap conductor pair is consequently formed, the third common mode trap conductor to the first radial distance along The length of common mode trap 1201 is to rewind configuration spiral.Meanwhile the 7th common mode trap conductor 1224 and the 8th common mode trap Device conductor 1225 is fixed to the second capacitor 1220, and the 4th common mode trap conductor pair, the 4th common mode trap is consequently formed Conductor in the second radial distance along the length of common mode trap 1201 to rewind configuration spiral.In addition, the 9th common mode is fallen into Wave device conductor 1232 and the tenth common mode trap conductor 1233 are fixed to third capacitor 1230, and the 5th common mode trap is consequently formed Device conductor pair, the 5th common mode trap conductor in the first radial distance along the length of common mode trap 1201 to rewind Spiral is configured.Meanwhile the 11st common mode trap conductor 1234 and the 12nd common mode trap conductor 1235 be fixed to third electricity The 6th common mode trap conductor pair is consequently formed in container 1230, and the 6th common mode trap conductor is in the second radial distance Along the length of common mode trap 1201 to rewind configuration spiral.Further, 1242 He of the 13rd common mode trap conductor 14th common mode trap conductor 1243 is fixed to the 4th capacitor 1240, and the 7th common mode trap conductor pair is consequently formed, should 7th common mode trap conductor in the first radial distance along the length of common mode trap 1201 to rewind configuration spiral.Together When, the 15th common mode trap conductor 1244 and the 16th common mode trap conductor 1245 are fixed to the 4th capacitor 1240, by This formed the 8th common mode trap conductor pair, the 8th common mode trap conductor in the second radial distance along common mode trap The length of device 1201 is to rewind configuration spiral.Similar to example described above, each common mode trap conductor in common mode to falling into Corresponding capacitor (not shown) is fixed at the opposite end of wave device 1201.

In this way, the density of common mode trap 1201 can include 16 common mode trap conductors, and common mode trap Mutual inductance between center conductor is relative to the common mode trap increase compared with low-density.However, common mode trap and center Mutual inductance between conductor will not increase with the density linear of common mode trap.On the contrary, with the increase of density, the improvement of mutual inductance is opened Begin gradually to weaken.Therefore, there is compromise between the complexity of the increase of mutual inductance and higher density common mode trap, because with More common mode trap conductors keep the symmetry between common mode trap conductor pair to become to being added to common mode trap It is more difficult.

Figure 13 is the advanced frame for showing the exemplary method 1300 according to an embodiment of the invention for common mode trap Figure.Method 1300 starts from 1305.At 1305, method 1300 includes providing center conductor.Center conductor may be configured to example Such as generally similar to center conductor 210 described above.For example, center conductor can include the transmission cable of MRI machine, quilt It is configured to RF coils being connected to one or more processing elements.

At 1310, method 1300 includes setting dielectric spacer around center conductor.Specifically, dielectric spacer It can radially set and can extend along at least part of the length of center conductor around center conductor.It is for example, electric Dielectric spacers can have through its preformed through-hole or hole, be sized to receive center conductor, and can be one The appropriate location of outer sleeve fixed to center conductor at a or multiple positions.Dielectric spacer may be configured to for example Generally similar to above-described dielectric spacer 304.Furthermore, it is possible to around dielectric spacer setting outer sleeve or screen It covers.In some instances, outer sleeve can be discontinuous to expose at least part of dielectric spacer.

At 1315, method 1300 includes winding two altogether in the opposite direction with radial distance around dielectric spacer Mould trapper conductor, to form the first common mode trap conductor pair on the first side of center conductor.Specifically, the first common mode is fallen into Wave device conductor can in a first direction on (for example, clockwise) around dielectric spacer with can be tapered or can not Tapered radial distance spiral winding, and the second common mode trap conductor can be in second direction (for example, counterclockwise) Around dielectric spacer with can it is tapered or can not be tapered radial distance spiral winding.As illustrative and unrestricted The example of property, every one end of common mode trap conductor can be located in the column or capacitance of every at one end of common mode trap Device.Note that discribed in example as described in the present specification, " side " of cylindrical center conductor can be understood as parallel In the axis of the central axis of center conductor, extend along the outer surface of center conductor.As non-limiting example, the first He Second common mode trap conductor can include tape conductor or conducting wire.The spiral-shaped of first common mode trap conductor can be gradually Contracting so that the end of the first and second common mode trap conductors is substantially close to the end of dielectric spacer, and first is common The middle part of mould trapper conductor is spaced apart radial distance with dielectric spacer.

At 1320, method 1300 includes winding two altogether in the opposite direction with radial distance around dielectric spacer Mould trapper conductor, to form the second common mode trap conductor pair in the second side of the center conductor opposite with the first side.Tool Body, third common mode trap conductor can in a first direction around dielectric spacer with tapered or non-tapered radial direction away from From winding, and the 4th common mode trap conductor can be in a second direction around dielectric spacer with tapered or non-tapered diameter It is wound to distance.For example, the 4th common mode trap conductor can be to have the spiral with being limited by third common mode trap conductor It the spiral of similar spacing but is wound on different directions (for example, clockwise and anticlockwise).It should be noted that first and the Two common mode trap conductors and the third and fourth common mode trap conductor fully can loosely be twined around dielectric spacer Around so that if center conductor and dielectric spacer bending or flexure, common mode trap conductor will not be bonded to each other or join It connects.It can be tapered as above to the spiral formed by the second common mode trap conductor.

At 1325, method 1300 includes will be by center conductor, dielectric spacer and the first and second common mode traps Device conductor is connected to the transmission cable of formation the component of the MRI systems in the hole of MRI system.For example, transmission cable is connected to At least one processing component (for example, T/R switches and/or data collecting system) and RF coils of MRI system.Particularly, it transmits One end of cable is connected to processing component, and the other end of transmission cable is connected to RF coils.Therefore, transmission cable can be used for example Such as will the signal transmission from receiving coil to processing component for image reconstruction.As another example, transmission cable is set A part in RF coils or as RF coils.Then, method 1300 can terminate.

As another example, Figure 14 is to show the exemplary method according to an embodiment of the invention for common mode trap 1400 high level block diagram.Method 1400 starts from 1405.At 1405, method 1400 includes providing center conductor.Center conductor can To be configured to for example generally similar to center conductor 210 described above.For example, center conductor can include the biography of MRI machine Transmission cable is configured as RF coils being connected to one or more processing elements.

At 1410, method 1400 includes setting four capacitors around center conductor.Specifically, it is for example, such as above Described in conjunction with Figure 8, two capacitors can be arranged on the opposite side of the center conductor of every at one end of common mode trap.

At 1415, method 1400 includes winding two altogether in the opposite direction with the first radial distance around center conductor Mould trapper conductor, to form the first common mode trap conductor pair on the first side of center conductor.Specifically, the first common mode is fallen into Wave device conductor can in a first direction on (for example, clockwise) around center conductor with can be tapered or can not be tapered The first radial distance spiral winding, and the second common mode trap conductor can be in second direction (for example, counterclockwise) Around center conductor with can it is tapered or can not be tapered the first radial distance spiral winding.As illustrative and unrestricted Property example, the end of common mode trap conductor can be located in the first capacitor of the at one end of common mode trap and fixed Second capacitor of the position at the other end of common mode trap.As non-limiting example, the first and second common mode traps are led Body can include tape conductor or conducting wire.The spiral-shaped of first and second common mode trap conductors can be tapered so that The end of first and second common mode trap conductors is substantially close to the end of dielectric spacer, and the first and second common modes are fallen into The middle part of wave device conductor is spaced apart radial distance with dielectric spacer.

At 1420, method 1400 includes around center conductor being more than the second radial distance of the first radial distance in phase Two common mode trap conductors are wound in the reverse direction, to form the second common mode trap conductor on the first side of center conductor It is right.Specifically, third common mode trap conductor can be in a first direction around center conductor with tapered or non-tapered radial direction Distance winding, and the 4th common mode trap conductor can be in a second direction around center conductor with tapered or non-tapered radial direction Distance winding.For example, the 4th common mode trap conductor can be to have the spiral phase with being limited by third common mode trap conductor As spacing spiral but wound on different directions (for example, clockwise and anticlockwise).Third and fourth common mode trap Conductor is connected to the first and second capacitors.It should be noted that the first and second common mode trap conductors and third and fourth common Mould trapper conductor fully can loosely be wound around dielectric spacer so that if center conductor and dielectric spacer Bending or flexure, common mode trap conductor will not be bonded to each other or couple.By the second common mode trap conductor to the spiral shell that is formed Rotation can be tapered as above.

At 1425, method 1400 includes winding two altogether in the opposite direction with the first radial distance around center conductor Mould trapper conductor, to form third common mode trap conductor pair, the third common mode trap conductor is to being connected to first The third and fourth capacitor in the second side of the opposite center conductor in side.

Similarly, at 1430, method 1400 includes twining with the second radial distance in the opposite direction around center conductor Around two common mode trap conductors, to form the 4th common mode trap conductor pair, the 4th common mode trap conductor is to being connected to The third and fourth capacitor in the second side of center conductor.

At 1435, method 1400 includes will be by the transmission of center conductor, capacitor and common mode trap conductor to being formed Cable connection is to the component of the MRI system in the hole of MRI system.For example, transmission cable is connected at least one of MRI system Processing component (for example, T/R switches and/or data collecting system) and RF coils.Particularly, one end of transmission cable connects everywhere Component is managed, the other end of transmission cable is connected to RF coils.Therefore, can be used for for example will be from receiving coil for transmission cable Signal transmission is to processing component for image reconstruction.As another example, transmission cable is arranged in RF coils or as RF A part for coil.Then, method 1400 can terminate.

The technique effect of the disclosure can include due to the reduction between transmission cable and coil part interaction and The performance of improved MRI system.Another technique effect of the disclosure can include the heat for example by the way that common mode trap is generated Amount is distributed in larger area and/or reduces, minimizes or prevent hot spot and improve heat distribution.The another technique effect of the disclosure It can include ensuring that and common mode obstruction or trap are provided at all appropriate positions along transmission cable.Another skill of the disclosure Art effect can include the improved flexibility of common mode trap component.The another technique effect of the disclosure can be fallen into including common mode The rotation of wave device relative to each other.Another technique effect of the disclosure can include the tapered of common mode trap conductor.The disclosure Another technique effect can include improved mutual inductance between common mode trap component and center conductor.

In one embodiment, it is a kind of to include for the common mode trap of magnetic resonance imaging (MRI) device：First conductor and Second conductor, the length around center conductor are rewound, wherein, the first and second conductors and center conductor are radially spaced apart the One distance, wherein, the first and second conductors are fixed to the first side of center conductor；And third conductor and the 4th conductor, it encloses Length around center conductor is rewound, wherein, the third and fourth conductor is radially spaced apart the first distance, and its with center conductor In, the third and fourth conductor is fixed to the second side of the center conductor opposite with the first side.

In the first example of common mode trap, the first and second conductors orthogonally crossedpath.Optionally including the In second example of one exemplary common mode trap, common mode trap is further included to be set along length radially around center conductor Dielectric spacer, wherein, first, second, third and fourth conductor around dielectric spacer rewind.Optionally including In the third example of the common mode trap of one or more of first and second examples, common mode trap further includes：First He Second capacitor is positioned in every at one end of the length along the first side；And third and fourth capacitor, it is positioned In every at one end of the length along the second side, wherein, the first and second conductors are fixed to the first and second capacitors, and its In, the third and fourth conductor is fixed to the third and fourth capacitor.Optionally include first to third example in one or In 4th example of multiple common mode traps, common mode trap further includes：5th conductor and the 6th conductor, lead around center The length back-roll of body, wherein, the 5th and the 6th conductor is radially spaced apart the second distance more than the first distance with center conductor, Wherein, the first and second conductors are fixed to the first and second capacitors on the first side of center conductor；And the 7th conductor With the 8th conductor, the length around center conductor is rewound, wherein, the 7th and the 8th conductor is radially spaced apart with center conductor Second distance, and wherein, the 7th and the 8th conductor is fixed to the third and fourth capacitor in the second side of center conductor. In optionally the 5th example of common mode trap of one or more of first to fourth example is included, common mode trap is also Including：5th and the 6th capacitor, along the third side positioning equidistant with first and second sides length every at one end；With And the 7th and the 8th capacitor, along relatively being positioned with third side and fourth side positioning equidistant with first and second sides exists Every at one end of length.In the 6th example of the common mode trap for optionally including one or more of the first to the 5th example In, common mode trap further includes：5th conductor and the 6th conductor, the length around center conductor are rewound, wherein, the 5th and the Six conductors and center conductor are radially spaced apart the first distance, wherein, the 5th and the 6th conductor is fixed to the of center conductor The the 5th and the 6th capacitor on three sides；And the 7th conductor and the 8th conductor, the length around center conductor are rewound, In, the 7th and the 8th conductor is radially spaced apart the first distance, and wherein with center conductor, and the 7th and the 8th conductor is fixed to The the 7th and the 8th capacitor on the 4th side of center conductor.One or more in the first to the 6th example is optionally included In 7th example of a common mode trap, common mode trap is tuned to provide the resonance close to the working frequency of MRI system Frequency.In optionally the 8th example of common mode trap of one or more of the first to the 7th example is included, common mode is fallen into Wave device further includes multiple annular disks that center conductor setting is surrounded with aturegularaintervals, wherein, each in conductor is described in Each annular disk in multiple annular disks.

In another embodiment, it is a kind of to include for the common mode trap component of magnetic resonance imaging (MRI) system：Center Conductor with length and is configured to transmit signal between the MRI radio-frequency coils and processing element of MRI system；It is and more A common mode trap, at least part along the length of center conductor extend, and the common mode trap is configured to provide Impedance to reduce the transmitter driving current of MRI system, wherein, each common mode trap includes the second length and including multiple Conductor pair, each conductor of the multiple pairs of conductors is to including the first conductor and the second conductor around center conductor back-roll.

In the first example of common mode trap component, each common mode trap includes being located in the first of common mode trap More than first a capacitors at end and more than second a capacitors being located at the second end of common mode trap, wherein, common mode is fallen into First and second common mode trap conductors of wave device are fixed to more than first a capacitors and more than second a capacitors.Optionally wrapping In the second example for including the first exemplary common mode trap component, for each conductor pair of multiple pairs of conductors, the first conductor With the second conductor orthogonally crossedpath.In the common mode trap for optionally including one or more of the first and second examples In the third example of component, each in multiple common mode traps is adjacently set.Optionally including first to third In 4th example of the common mode trap component of one or more of example, each common mode trap is included around center conductor The radially dielectric spacer of setting.

In yet another embodiment, it is a kind of to be used to provide transmission for radio frequency (RF) coil of magnetic resonance imaging (MRI) system The method of cable includes：It provides with length and is configured to transmit signal between the RF coils and processing element of MRI system Center conductor；And at least part of the length along center conductor positions multiple common mode trap conductors around center conductor It is right, wherein, multiple common mode trap conductors are symmetrical to surrounding center conductor, wherein, each common mode trap conductor is to packet The first common mode trap conductor and the second common mode trap conductor are included, the first common mode trap conductor is along center conductor The part of length surrounds center conductor spiral winding in a first direction, and the second common mode trap conductor is along length The part around center conductor spiral winding in a second direction that is opposite the first direction.

In first example of this method, the first the half of multiple common mode trap pairs of conductors are positioned in away from center conductor The first radial distance of central axis, and the second the half of multiple common mode trap pairs of conductors are positioned in away from central axis Second radial distance, the second radial distance are more than the first radial distance.Optionally including the second of the first exemplary method In example, the first and second common mode trap conductors are positioned at the midpoint of the length radially central shaft away from center conductor At the first distance of line and length every at one end radially away from central axis second distance at, second distance be less than first Distance.In optionally the third example of method of one or more of the first and second examples is included, first and second is common Mould trapper conductor is located in the column at the first and second ends of length.In optionally including first to third example One or more methods the 4th example in, this method further includes：Electric Jie is radially provided along the length of center conductor Matter spacer；And by multiple common mode trap conductors to being connected to dielectric spacer.Optionally including first to fourth In 5th example of the method for one or more of example, this method further includes offer radially around dielectric spacer Shielding.

As used herein, it describes in the singular and follows the element or step after word "a" or "an" that should manage It solves to be not excluded for a plurality of element or steps, such exclusion unless explicitly stated.In addition, " the implementation to the present invention The reference of example " is not intended to the presence for being interpreted to exclude the additional embodiment also in relation with institute's features set forth.It is in addition, unless opposite Ground clearly states, and the embodiment of the element of "comprising", " comprising " or " having " with special properties or multiple element may include not having That property adds this class component.Term " comprising " and the common language of " wherein " as corresponding term "comprising" He " wherein " Say equivalent.In addition, term " first ", " second " and " third " etc. is only used as label, number is applied to its object without being intended to Word requires or specific position order.

This written description includes the present invention of optimal mode, and also make the ordinary skill people of this field with example come open Member can implement the present invention, including manufacture and using any device or system and perform any method being included.The present invention Patentable scope be defined in the claims, and may include the other examples that those of ordinary skill in the art expect.Such as The such other examples of fruit have the not structural element different from the literal language of claims or if they include and power Equivalent structural elements of the literal language of sharp claim without essence difference, then they are set within the scope of the claims.

Claims

1. one kind is used for the common mode trap of magnetic resonance imaging (MRI) device, including：

First conductor and the second conductor, first conductor and second conductor are rewound around the length of center conductor, wherein, First and second conductor is radially spaced apart the first distance with the center conductor, wherein, first and second conductor The first side fixed to the center conductor；And

Third conductor and the 4th conductor, the third conductor and the 4th conductor are anti-around the length of the center conductor Around, wherein, third and fourth conductor is radially spaced first distance, and wherein with the center conductor, described Third and fourth conductor is fixed to the second side of the center conductor opposite with first side.

2. common mode trap according to claim 1, wherein, first and second conductor orthogonally crossedpath.

3. common mode trap according to claim 1 is further included along the length radially around the center conductor The dielectric spacer of setting, wherein, the first, second, third and fourth conductor is rewound around the dielectric spacer.

4. common mode trap according to claim 1, further includes：First and second capacitors, first and second electricity Container is positioned in every at one end of the length along first side；And third and fourth capacitor, the third Every at one end of the length along the second side is positioned in the 4th capacitor, wherein, described first and second lead Body is fixed to first and second capacitor, and wherein, and third and fourth conductor is fixed to described third and fourth Capacitor.

5. common mode trap according to claim 4, further includes：

5th conductor and the 6th conductor, the 5th conductor and the 6th conductor are anti-around the length of the center conductor Around, wherein, the 5th conductor and the 6th conductor are radially spaced apart with the center conductor more than first distance Second distance, wherein, first and second conductor is fixed to described the on first side of the center conductor One capacitor and second capacitor；And

7th conductor and the 8th conductor, the 7th conductor and the 8th conductor are anti-around the length of the center conductor Around, wherein, the 7th and the 8th conductor is radially spaced apart the second distance, and wherein with the center conductor, institute It states the 7th and the 8th conductor and is fixed to the third capacitor and the described 4th in the second side of the center conductor Capacitor.

6. common mode trap according to claim 4, further includes：5th and the 6th capacitor, the 5th and the 6th electricity Container along the third side positioning equidistant with the first and second sides the length every at one end；And the 7th and the 8th Capacitor, the 7th and the 8th capacitor along relatively positioned with the third side and with the first and second sides it is equidistant The 4th side positioning the length every at one end.

7. common mode trap according to claim 6, further includes：

5th conductor and the 6th conductor, the 5th conductor and the 6th conductor are anti-around the length of the center conductor Around, wherein, the 5th conductor and the 6th conductor are radially spaced apart first distance with the center conductor, In, the 5th and the 6th conductor is fixed to the 5th capacitor on the third side of the center conductor and described 6th capacitor；And

7th conductor and the 8th conductor, the 7th conductor and the 8th conductor are anti-around the length of the center conductor Around, wherein, the 7th and the 8th conductor is radially spaced apart first distance, and wherein with the center conductor, institute It states the 7th and the 8th conductor and is fixed to the 7th capacitor and the described 8th on the 4th side of the center conductor Capacitor.

8. common mode trap according to claim 1, wherein, the common mode trap is tuned to provide close to described The resonant frequency of the working frequency of MRI system.

9. one kind is used for the common mode trap component of magnetic resonance imaging (MRI) system, including：

Center conductor with length and is configured to transmit between the MRI radio-frequency coils and processing element of the MRI system Signal；And

Multiple common mode traps, at least part along the length of the center conductor extend, the common mode trap Device is configured to provide impedance to reduce the transmitter driving current of the MRI system, wherein, it is every in the common mode trap One includes the second length and including multiple conductors pair, each conductor of the multiple pairs of conductors to include surrounding it is described in The first conductor and the second conductor of heart conductor back-roll.

10. one kind is used for the method for providing transmission cable for radio frequency (RF) coil of magnetic resonance imaging (MRI) system, including：

Center conductor is provided, the center conductor has length and is configured to the RF coils in the MRI system and place Signal is transmitted between reason element；And

Multiple common mode traps are positioned along at least part of the length of the center conductor around the center conductor to lead Body pair, wherein, the multiple common mode trap conductor is symmetrical to surrounding the center conductor, wherein, each common mode trap Device conductor to including the first common mode trap conductor and the second common mode trap conductor, the first common mode trap conductor along The part of the length of the center conductor is around center conductor spiral winding in a first direction, and described second Common mode trap conductor is along the part of the length around the center conductor opposite to the first direction the Spiral winding on two directions.