CN101548193B - Mri用鸟笼式发射天线 - Google Patents

Mri用鸟笼式发射天线 Download PDF

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CN101548193B
CN101548193B CN2008800010129A CN200880001012A CN101548193B CN 101548193 B CN101548193 B CN 101548193B CN 2008800010129 A CN2008800010129 A CN 2008800010129A CN 200880001012 A CN200880001012 A CN 200880001012A CN 101548193 B CN101548193 B CN 101548193B
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CN101548193A (zh
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勒兹万·拉泽尔
沃尔夫冈·伦茨
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
    • G01R33/32—Excitation or detection systems, e.g. using radio frequency signals
    • G01R33/34—Constructional details, e.g. resonators, specially adapted to MR
    • G01R33/34046—Volume type coils, e.g. bird-cage coils; Quadrature bird-cage coils; Circularly polarised coils
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
    • G01R33/32—Excitation or detection systems, e.g. using radio frequency signals
    • G01R33/34—Constructional details, e.g. resonators, specially adapted to MR
    • G01R33/34046—Volume type coils, e.g. bird-cage coils; Quadrature bird-cage coils; Circularly polarised coils
    • G01R33/34076—Birdcage coils
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
    • G01R33/32—Excitation or detection systems, e.g. using radio frequency signals
    • G01R33/36—Electrical details, e.g. matching or coupling of the coil to the receiver
    • G01R33/3642—Mutual coupling or decoupling of multiple coils, e.g. decoupling of a receive coil from a transmission coil, or intentional coupling of RF coils, e.g. for RF magnetic field amplification
    • G01R33/3657—Decoupling of multiple RF coils wherein the multiple RF coils do not have the same function in MR, e.g. decoupling of a transmission coil from a receive coil
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
    • G01R33/42—Screening
    • G01R33/422—Screening of the radio frequency field
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
    • G01R33/32—Excitation or detection systems, e.g. using radio frequency signals
    • G01R33/36—Electrical details, e.g. matching or coupling of the coil to the receiver
    • G01R33/3642—Mutual coupling or decoupling of multiple coils, e.g. decoupling of a receive coil from a transmission coil, or intentional coupling of RF coils, e.g. for RF magnetic field amplification

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Abstract

一种磁共振用发射天线，其具有复数个自第一末端(1′)延伸至第二末端(1″)的天线杆(1)。所述天线杆(1)围绕一中心轴分布。所述天线杆在第一末端(1′)由第一端接元件(3)端接，所述第二末端(1″)由第二端接元件(6)端接。所述第一端接元件(3)设计为具有复数个端环段(4)的端环，所述端环段通过端环电容(5)彼此耦合。所述第二端接元件(6)采取不同于所述第一端接元件(3)的设计。所述发射天线具有可使所述发射天线失谐的失谐电路(7)。所述失谐电路(7)布置在所述第二端接元件(6)一侧。

Description

MRI用鸟笼式发射天线
技术领域
本发明涉及一种磁共振用发射天线。
背景技术
磁共振成像(尤其是头部的磁共振成像)越来越多地采用分离式的发射天线和接收天线。这类天线通常又称为线圈。在使用分离式的发射天线和接收天线的情况下，要求发射天线采用可失谐设计。
在现有技术中，发射天线通常设计为鸟笼式谐振器。在此情况下，发射天线通常具有两个用作端接元件的端环，其中，这两个端环采取相同设计。端环特定而言由复数个端环段构成，这些端环段通过端环电容器彼此耦合。个别情况下也用所谓的TEM谐振器来代替鸟笼式谐振器。
现有技术中的已知发射天线在待检对象对称以及静态磁场相对较弱(约1.5特斯拉以下)的情况下工作良好。但是当待检对象不对称，静态磁场较强(例如3特斯拉及以上)时，射频发射场的质量会有所下降。
EP 0498539A1中公开过一种磁共振用发射天线，这种发射天线具有复数个自第一末端延伸至第二末端的天线杆。这些天线杆至少基本平行于一中心轴延伸，并围绕中心轴分布。天线杆在第一末端由第一端接元件端接，在第二末端由第二端接元件端接。第一端接元件设计为一个具有复数个端环段的端环，这些端环段通过端环电容器彼此耦合。这种发射天线具有可使发射天线失谐的失谐电路。失谐电路布置在第二端接元件一侧。
DE 10306998B3和US 6,344,745B1所揭示的内容与EP 0498539A1相似。
US 4,782,298A中公开过一种磁共振用天线，这种天线具有多个天线组成部分，其中，这些天线组成部分之间布置有复数个可使天线失谐的PIN二极管。
发明内容
本发明的目的是提供一种磁共振用发射天线，这种发射天线即使在待检对象不对称、静态磁场较强的情况下也能提供高质量的射频发射场。
这个目的通过一种具有权利要求1的特征的磁共振用发射天线而达成。有利改进方案由各从属权利要求给出。
本发明涉及一种磁共振用发射天线，其中，
-所述发射天线具有复数个自第一末端延伸至第二末端的天线杆，
-所述天线杆至少基本平行于一中心轴延伸，并围绕所述中心轴分布，
-所述天线杆在第一末端由第一端接元件(terminating element)端接(terminate)，在第二末端由第二端接元件端接，
-所述第一端接元件设计为具有复数个端环段的端环，所述端环段通过端环电容彼此耦合，
-所述发射天线具有一个能使所述发射天线失谐的失谐电路，
所述失谐电路布置在所述第二端接元件一侧，
所述第二端接元件或者设计为完全连续式短路环，且所述失谐电路布置在所述天线杆与所述第二端接元件之间，或者具有复数个端环段，所述端环段之间布置有所述失谐电路，而不是端环电容器，以及
所述第二端接元件的截面大于所述第一端接元件的截面。
若以中心轴为基准，所述发射天线通常具有一个在径向外侧包围天线杆的射频屏蔽件。
为能优化射频发射场的质量，在以中心轴为基准的情况下，从径向看，天线杆与射频屏蔽件之间可以存在一个天线杆间距，这个天线杆间距在第一端接元件到第二端接元件之间可以发生变化。这种变化特定而言可以是线性变化。
作为替代或补充方案，在以中心轴为基准的情况下，从径向看，第一端接元件与射频屏蔽件之间可以存在一个第一端接元件间距，第二端接元件与射频屏蔽件之间可以存在一个第二端接元件间距，这两个端接元件间距可以彼此不等。
为能实现相对较大的截面，第二端接元件特定而言可在径向厚度相同的情况下具有大于第一端接元件的轴向宽度。
所述发射天线原则上可设计为全身天线。其优选设计为头部线圈。
所述发射天线原则上可调整为任意大小的谐振频率。所述发射天线优选调整为至少与3特斯拉静态磁场中的氢的拉莫尔频率一样大的谐振频率。
失谐电路优选具有复数个PIN二极管，其中，这些PIN二极管处于接通状态时，发射天线调整为谐振频率。
所述发射天线通常具有复数个用于向发射天线输送信号和/或用于从发射天线输出信号的传输线。这些传输线优选布置在第二端接元件一侧。
附图说明
下面借助附图和实施例对其他优点和技术细节进行说明，其中：
图1为磁共振用发射天线的侧视图；
图2为图1所示的发射天线的截面图；
图3为图1所示的发射天线的第一方案的展开图；
图4为图1所示的发射天线的第二方案的展开图；
图5为另一发射天线的局部侧视图；以及
图6为图5所示的发射天线的局部展开图。
具体实施方式
如图1和图2所示，磁共振用发射天线具有复数个天线杆1。每个天线杆1均自相应天线杆1的第一末端1′延伸至第二末端1″。
根据一种优选设计方案，天线杆1(至少基本)平行于中心轴2延伸。天线杆1的数量最小为四。通常为十六或三十二。但也可以采用其他数量，例如六、八、十二、二十四或四十个天线杆1。
一般情况下，天线杆1都精确地平行于中心轴2延伸。但也可以采用替代性设计方案，即天线杆1所定义的方向只是基本平行于中心轴2。在第二种情况下，各天线杆1所呈现的方向具有第一子分量和第二子分量。这两个子分量互为补充，从而构成天线杆1的方向。
第一子分量(精确地)平行于中心轴2。第二子分量与中心轴2正交。只要第一子分量大于第二子分量，天线杆1的方向就基本平行于中心轴2。举例而言，通过下述方式可使天线杆1只是基本平行于中心轴2延伸，即：将发射天线设计为略呈锥形(参见图1和图2)，和/或天线杆1像枪管膛线那样略呈螺旋状地环绕中心轴2延伸。也可将这两种措施结合起来。
举例而言，发射天线可设计为全身天线。发射天线优选设计为如图1所示的头部线圈。
下文所使用的“轴向”、“径向”和“切向”等概念总是以某一轴线(例如中心轴2)为基准。“轴向”这一概念表示的是平行于相应轴线的方向。“径向”和“切向”这两个概念表示的是与相应轴线正交的一个平面内的方向。“径向”表示这个平面内朝向或背离相应轴线的方向。“切向”表示的是与轴线正交的平面内环绕轴线的方向。如果本说明书在未明确指出以哪一轴线为基准的情况下使用“轴向”、“径向”和“切向”等概念，作为基准的轴线的就是中心轴2。如果是以其他轴线为基准，本说明书就会补充说明具体涉及的是那条轴线。
天线杆1在第一末端1′由第一端接元件3端接。第一端接元件3设计为端环，具有复数个端环段4。这些端环段4通过端环电容器5彼此耦合。
天线杆1在第二末端1″由第二端接元件6端接。如图1和图2所示，第二端接元件6设计为另一端环。但第二端接元件6都采取不同于第一端接元件3的设计。下文将联系图1至图4对此进行详细说明。
如图1所示，发射天线调整为谐振频率fR。谐振频率fR原则上可以是任意大小的频率。举例而言，谐振频率fR至少可与3特斯拉静态磁场中氢的拉莫尔频率fL(H，3T)一样大。
发射天线还具有一个失谐电路7。当失谐电路7未启动时(失谐情况)，发射天线不调整为谐振频率fR。也就是说，发射天线在谐振频率fR下不发生谐振，而是处于失谐状态。而当失谐电路7启动时(调谐情况)，发射天线在谐振频率fR下发生谐振，也就是说，发射天线调整为谐振频率fR。
图1和图2未对失谐电路7进行图示。但图3、图4和图5对其进行了图示。如图3、图4和图5所示，失谐电路7布置在第二端接元件6一侧。
以上是对本发明的基本原理的说明。下面将联系图1至图4对本发明的可行设计方案进行说明。
如图1和图2所示，发射天线具有一个射频屏蔽件8。射频屏蔽件8在径向外侧包围天线杆1。从径向看，第一端接元件3与射频屏蔽件8之间存在一个间距a，下文称之为第一端接元件间距a。从径向看，天线杆1与射频屏蔽件8之间存在一个间距b，下文称之为天线杆间距b。
在图1和图2所示的设计方案(即第二端接元件6设计为另一端环，因而构成一个不同于射频屏蔽件8的元件6)中，从径向看，第二端接元件6与射频屏蔽件8之间存在一个间距c，下文称之为第二端接元件间距c。
天线杆间距b在第一端接元件3到第二端接元件6之间可以保持恒定不变。无论天线杆1是平行于中心轴2延伸，还是定义一个截锥体(如图1和图2所示)，都可实现这一设计方案。但如果天线杆间距b在第一端接元件3到第二端接元件6之间发生变化(同样如图1所示)，就可使发射天线的发射特性得到优化。其中，天线杆间距b可做线性变化。个别情况下也可采用其他变化方式。举例而言，射频屏蔽件8可以呈直线延伸，天线杆1可以呈抛物线延伸或以其他方式发生弯曲。
在图1和图2所示的设计方案(即第二端接元件6构成一个不同于射频屏蔽件8的元件6)中，第二端接元件间距c可以等于第一端接元件间距a。但第二端接元件间距c与第一端接元件间距a优选不相等。
如图5和图6所示，作为图1和图2(以及图3和图4)所示的设计方案的替代方案，第二端接元件6和射频屏蔽件8可为同一元件。在此情况下就无需再定义第二端接元件间距。但其余的实施方案(尤其是与天线杆间距b的特性有关的实施方案)仍然是可用的。
如上文所述以及如图1至图4所示，第二端接元件6可设计为另一端环。在此情况下，这个另一端环(＝第二端接元件6)必须采用不同于端环(＝第一端接元件3)的设计。举例而言，另一端环6的截面可以大于端环3的截面。其中，实现这一较大截面的方法是，在(从径向看)端环3、6的厚度d1、d2相等的情况下，另一端环6(从轴向看)的宽度b2大于端环3的宽度b1。
另一端环6的截面优选应明显大于端环3的截面。“明显”这一概念在此指的是，另一端环6的截面至少是端环3的截面的两倍。另一端环6的截面优选至少是端环3的截面的三倍，例如四倍至六倍。
鉴于这种设计方案(特别是截面相对较大的设计方案)，另一端环6(＝第二端接元件6)的电感通常小于端环3(＝第一端接元件3)的电感。但这一点并非是必须的。
作为截面采用不同尺寸这一方案的替代或补充方案，另一端环6可设计为如图3和图4所示的连续式短路环。“连续式短路环”这一概念在此指的是，另一端环6(参见图3)采取完全连续式设计，即其总是且一定处于短接状态。在此情况下，失谐电路7如图3所示布置在天线杆1与另一端环6(＝第二端接元件6)之间。作为替代方案，“连续式短路环”这一概念也可表示，另一端环6虽然(和端环3一样)具有复数个端环段9。但另一端环6的这些端环段9之间并未布置端环电容器。采用这种方案的第二端接元件6中布置有失谐电路7。图4对这种设计方案进行了图示。
失谐电路7通常具有复数个PIN二极管10，参见图3、图4和图5。当PIN二极管10未接通时，发射天线优选不调整为谐振频率fR。但当PIN二极管10接通时，发射天线优选调整为谐振频率fR。
当PIN二极管10接通时，这些PIN二极管处于导电状态。因此，当PIN二极管10处于接通状态时(即在调谐情况下)，如果失谐电路7布置在另一端环6中，另一端环6就同样起到连续式短路环的作用。
需要向发射天线输送信号。这些信号可以是低频信号。这种低频信号的一个例子就是用来控制失谐电路7的失谐电压。输送给发射天线的信号也可以是射频信号。这种信号的一个例子就是输入发射天线的发射电流。此外，发射天线还可输出信号(特别是射频信号)。在发射天线也可用作接收天线的情况下，这种信号的一个例子就是发射天线所接收到的信号。可以输出的射频信号的另一例子就是由微波接收器接收的微波信号，这些微波接收器整合在天线杆1中。附图并未对这些微波接收器进行图示。
上述信号的输送和输出通过传输线11而实现。如图1至图6所示，传输线11优选布置在第二端接元件6一侧。但这一点并非是必须的。
本发明的发射天线优点众多。其设计简单，效率高，可灵活确定尺寸、加以使用。
以上只是本发明的说明。本发明的保护范围仅由所附的权利要求确定。

Claims (10)

1.一种磁共振用发射天线，其中，
所述发射天线具有复数个自第一末端(1′)延伸至第二末端(1″)的天线杆(1)，
所述天线杆(1)至少基本平行于一中心轴(2)延伸，并围绕所述中心轴(2)分布，
所述天线杆(1)在所述第一末端(1′)由第一端接元件(3)端接，在所述第二末端(1″)由第二端接元件(6)端接，
所述第一端接元件(3)设计为具有复数个端环段(4)的端环，所述端环段通过端环电容器(5)彼此耦合，
所述发射天线具有一个能使所述发射天线失谐的失谐电路(7)，
所述第二端接元件(6)或者设计为完全连续式短路环，且所述失谐电路(7)布置在所述天线杆(1)与所述第二端接元件(6)之间，或者具有复数个端环段(9)，所述端环段之间布置有所述失谐电路(7)，而不是端环电容器，以及
所述第二端接元件(6)的截面大于所述第一端接元件(3)的截面。
2.根据权利要求1所述的发射天线，其特征在于，
在以所述中心轴(2)为基准的情况下，所述发射天线具有一个在径向外侧包围所述天线杆(1)的射频屏蔽件(8)。
3.根据权利要求2所述的发射天线，其特征在于，
在以所述中心轴(2)为基准的情况下，从径向看，所述天线杆(1)与所述射频屏蔽件(8)之间存在一个天线杆间距(b)，所述天线杆间距(b)在所述第一端接元件(3)到所述第二端接元件(6)之间发生变化。
4.根据权利要求3所述的发射天线，其特征在于，所述变化是线性变化。
5.根据权利要求2或3或4所述的发射天线，其特征在于，
在以所述中心轴(2)为基准的情况下，从径向看，所述第一端接元件(3)与所述射频屏蔽件(8)之间存在一个第一端接元件间距(a)，所述第二端接元件(6)与所述射频屏蔽件(8)之间存在一个第二端接元件间距(c)，所述端接元件间距(a，c)彼此不等。
6.根据权利要求1所述的发射天线，其特征在于，
以所述中心轴(2)为基准，所述第二端接元件(6)与所述第一端接元件(3)在径向厚度(d2)相同的情况下，所述第二端接元件(6)具有大于所述第一端接元件(3)的轴向宽度(b2)。
7.根据权利要求1所述的发射天线，其特征在于，
所述发射天线设计为头部线圈。
8.根据权利要求1所述的发射天线，其特征在于，
所述发射天线调整为至少与3特斯拉静态磁场中氢的拉莫尔频率(fL)一样大的谐振频率(fR)。
9.根据权利要求1所述的发射天线，其特征在于，
所述失谐电路(7)包括复数个PIN二极管(10)，其中，当所述PIN二极管(10)处于接通状态时，所述发射天线调整为谐振频率(fR)。
10.根据权利要求1所述的发射天线，其特征在于，
所述第二端接元件(6)未端接天线杆的一侧布置有复数个用于向所述发射天线输送信号和/或用于从所述发射天线输出信号的传输线(11)。
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Families Citing this family (128)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102007016313B4 (de) * 2007-04-04 2010-06-17 Siemens Ag Ganzkörperantenne für eine Magnetresonanzanlage und Magnetresonanzanlage mit einer solchen Ganzkörperantenne
DE102008062547B4 (de) 2008-12-16 2012-05-24 Siemens Aktiengesellschaft Magnetresonanzantenne
GB0905768D0 (en) * 2009-04-03 2009-05-20 Siemens Ag Antenna feed
DE102010041984B4 (de) * 2010-10-05 2014-02-27 Siemens Aktiengesellschaft Magnetresonanzantenne, sowie eine Magnetresonanzvorrichtung mit einer Magnetresonanzantenne
US9525524B2 (en) 2013-05-31 2016-12-20 At&T Intellectual Property I, L.P. Remote distributed antenna system
US9999038B2 (en) 2013-05-31 2018-06-12 At&T Intellectual Property I, L.P. Remote distributed antenna system
US8897697B1 (en) 2013-11-06 2014-11-25 At&T Intellectual Property I, Lp Millimeter-wave surface-wave communications
US9768833B2 (en) 2014-09-15 2017-09-19 At&T Intellectual Property I, L.P. Method and apparatus for sensing a condition in a transmission medium of electromagnetic waves
US10063280B2 (en) 2014-09-17 2018-08-28 At&T Intellectual Property I, L.P. Monitoring and mitigating conditions in a communication network
US9615269B2 (en) 2014-10-02 2017-04-04 At&T Intellectual Property I, L.P. Method and apparatus that provides fault tolerance in a communication network
US9685992B2 (en) 2014-10-03 2017-06-20 At&T Intellectual Property I, L.P. Circuit panel network and methods thereof
US9503189B2 (en) 2014-10-10 2016-11-22 At&T Intellectual Property I, L.P. Method and apparatus for arranging communication sessions in a communication system
US9973299B2 (en) 2014-10-14 2018-05-15 At&T Intellectual Property I, L.P. Method and apparatus for adjusting a mode of communication in a communication network
US9577306B2 (en) 2014-10-21 2017-02-21 At&T Intellectual Property I, L.P. Guided-wave transmission device and methods for use therewith
US9653770B2 (en) 2014-10-21 2017-05-16 At&T Intellectual Property I, L.P. Guided wave coupler, coupling module and methods for use therewith
US9769020B2 (en) 2014-10-21 2017-09-19 At&T Intellectual Property I, L.P. Method and apparatus for responding to events affecting communications in a communication network
US9780834B2 (en) 2014-10-21 2017-10-03 At&T Intellectual Property I, L.P. Method and apparatus for transmitting electromagnetic waves
US9312919B1 (en) 2014-10-21 2016-04-12 At&T Intellectual Property I, Lp Transmission device with impairment compensation and methods for use therewith
US9627768B2 (en) 2014-10-21 2017-04-18 At&T Intellectual Property I, L.P. Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith
US10243784B2 (en) 2014-11-20 2019-03-26 At&T Intellectual Property I, L.P. System for generating topology information and methods thereof
US9461706B1 (en) 2015-07-31 2016-10-04 At&T Intellectual Property I, Lp Method and apparatus for exchanging communication signals
US9997819B2 (en) 2015-06-09 2018-06-12 At&T Intellectual Property I, L.P. Transmission medium and method for facilitating propagation of electromagnetic waves via a core
US9544006B2 (en) 2014-11-20 2017-01-10 At&T Intellectual Property I, L.P. Transmission device with mode division multiplexing and methods for use therewith
US10340573B2 (en) 2016-10-26 2019-07-02 At&T Intellectual Property I, L.P. Launcher with cylindrical coupling device and methods for use therewith
US9742462B2 (en) 2014-12-04 2017-08-22 At&T Intellectual Property I, L.P. Transmission medium and communication interfaces and methods for use therewith
US9954287B2 (en) 2014-11-20 2018-04-24 At&T Intellectual Property I, L.P. Apparatus for converting wireless signals and electromagnetic waves and methods thereof
US10009067B2 (en) 2014-12-04 2018-06-26 At&T Intellectual Property I, L.P. Method and apparatus for configuring a communication interface
US9800327B2 (en) 2014-11-20 2017-10-24 At&T Intellectual Property I, L.P. Apparatus for controlling operations of a communication device and methods thereof
US9876570B2 (en) 2015-02-20 2018-01-23 At&T Intellectual Property I, Lp Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith
US9749013B2 (en) 2015-03-17 2017-08-29 At&T Intellectual Property I, L.P. Method and apparatus for reducing attenuation of electromagnetic waves guided by a transmission medium
JP6334444B2 (ja) * 2015-03-23 2018-05-30 株式会社日立製作所 磁気共鳴イメージング装置
US10224981B2 (en) 2015-04-24 2019-03-05 At&T Intellectual Property I, Lp Passive electrical coupling device and methods for use therewith
US9705561B2 (en) 2015-04-24 2017-07-11 At&T Intellectual Property I, L.P. Directional coupling device and methods for use therewith
US9793954B2 (en) 2015-04-28 2017-10-17 At&T Intellectual Property I, L.P. Magnetic coupling device and methods for use therewith
US9490869B1 (en) 2015-05-14 2016-11-08 At&T Intellectual Property I, L.P. Transmission medium having multiple cores and methods for use therewith
US9871282B2 (en) 2015-05-14 2018-01-16 At&T Intellectual Property I, L.P. At least one transmission medium having a dielectric surface that is covered at least in part by a second dielectric
US9748626B2 (en) 2015-05-14 2017-08-29 At&T Intellectual Property I, L.P. Plurality of cables having different cross-sectional shapes which are bundled together to form a transmission medium
US10650940B2 (en) 2015-05-15 2020-05-12 At&T Intellectual Property I, L.P. Transmission medium having a conductive material and methods for use therewith
US9917341B2 (en) 2015-05-27 2018-03-13 At&T Intellectual Property I, L.P. Apparatus and method for launching electromagnetic waves and for modifying radial dimensions of the propagating electromagnetic waves
US9866309B2 (en) 2015-06-03 2018-01-09 At&T Intellectual Property I, Lp Host node device and methods for use therewith
US9912381B2 (en) 2015-06-03 2018-03-06 At&T Intellectual Property I, Lp Network termination and methods for use therewith
US10812174B2 (en) 2015-06-03 2020-10-20 At&T Intellectual Property I, L.P. Client node device and methods for use therewith
US9913139B2 (en) 2015-06-09 2018-03-06 At&T Intellectual Property I, L.P. Signal fingerprinting for authentication of communicating devices
US9820146B2 (en) 2015-06-12 2017-11-14 At&T Intellectual Property I, L.P. Method and apparatus for authentication and identity management of communicating devices
US9865911B2 (en) 2015-06-25 2018-01-09 At&T Intellectual Property I, L.P. Waveguide system for slot radiating first electromagnetic waves that are combined into a non-fundamental wave mode second electromagnetic wave on a transmission medium
US9640850B2 (en) 2015-06-25 2017-05-02 At&T Intellectual Property I, L.P. Methods and apparatus for inducing a non-fundamental wave mode on a transmission medium
US9509415B1 (en) 2015-06-25 2016-11-29 At&T Intellectual Property I, L.P. Methods and apparatus for inducing a fundamental wave mode on a transmission medium
US9882257B2 (en) 2015-07-14 2018-01-30 At&T Intellectual Property I, L.P. Method and apparatus for launching a wave mode that mitigates interference
US10148016B2 (en) 2015-07-14 2018-12-04 At&T Intellectual Property I, L.P. Apparatus and methods for communicating utilizing an antenna array
US9628116B2 (en) 2015-07-14 2017-04-18 At&T Intellectual Property I, L.P. Apparatus and methods for transmitting wireless signals
US9853342B2 (en) 2015-07-14 2017-12-26 At&T Intellectual Property I, L.P. Dielectric transmission medium connector and methods for use therewith
US10205655B2 (en) 2015-07-14 2019-02-12 At&T Intellectual Property I, L.P. Apparatus and methods for communicating utilizing an antenna array and multiple communication paths
US9847566B2 (en) 2015-07-14 2017-12-19 At&T Intellectual Property I, L.P. Method and apparatus for adjusting a field of a signal to mitigate interference
US10044409B2 (en) 2015-07-14 2018-08-07 At&T Intellectual Property I, L.P. Transmission medium and methods for use therewith
US10090606B2 (en) 2015-07-15 2018-10-02 At&T Intellectual Property I, L.P. Antenna system with dielectric array and methods for use therewith
US9871283B2 (en) 2015-07-23 2018-01-16 At&T Intellectual Property I, Lp Transmission medium having a dielectric core comprised of plural members connected by a ball and socket configuration
US9948333B2 (en) 2015-07-23 2018-04-17 At&T Intellectual Property I, L.P. Method and apparatus for wireless communications to mitigate interference
US9749053B2 (en) 2015-07-23 2017-08-29 At&T Intellectual Property I, L.P. Node device, repeater and methods for use therewith
US9912027B2 (en) 2015-07-23 2018-03-06 At&T Intellectual Property I, L.P. Method and apparatus for exchanging communication signals
US9735833B2 (en) 2015-07-31 2017-08-15 At&T Intellectual Property I, L.P. Method and apparatus for communications management in a neighborhood network
US9967173B2 (en) 2015-07-31 2018-05-08 At&T Intellectual Property I, L.P. Method and apparatus for authentication and identity management of communicating devices
US9904535B2 (en) 2015-09-14 2018-02-27 At&T Intellectual Property I, L.P. Method and apparatus for distributing software
US9769128B2 (en) 2015-09-28 2017-09-19 At&T Intellectual Property I, L.P. Method and apparatus for encryption of communications over a network
US9729197B2 (en) 2015-10-01 2017-08-08 At&T Intellectual Property I, L.P. Method and apparatus for communicating network management traffic over a network
US9876264B2 (en) 2015-10-02 2018-01-23 At&T Intellectual Property I, Lp Communication system, guided wave switch and methods for use therewith
US10355367B2 (en) 2015-10-16 2019-07-16 At&T Intellectual Property I, L.P. Antenna structure for exchanging wireless signals
US9860075B1 (en) 2016-08-26 2018-01-02 At&T Intellectual Property I, L.P. Method and communication node for broadband distribution
US10135147B2 (en) 2016-10-18 2018-11-20 At&T Intellectual Property I, L.P. Apparatus and methods for launching guided waves via an antenna
US10374316B2 (en) 2016-10-21 2019-08-06 At&T Intellectual Property I, L.P. System and dielectric antenna with non-uniform dielectric
US9991580B2 (en) 2016-10-21 2018-06-05 At&T Intellectual Property I, L.P. Launcher and coupling system for guided wave mode cancellation
US10811767B2 (en) 2016-10-21 2020-10-20 At&T Intellectual Property I, L.P. System and dielectric antenna with convex dielectric radome
US9876605B1 (en) 2016-10-21 2018-01-23 At&T Intellectual Property I, L.P. Launcher and coupling system to support desired guided wave mode
US10312567B2 (en) 2016-10-26 2019-06-04 At&T Intellectual Property I, L.P. Launcher with planar strip antenna and methods for use therewith
US10291334B2 (en) 2016-11-03 2019-05-14 At&T Intellectual Property I, L.P. System for detecting a fault in a communication system
US10498044B2 (en) 2016-11-03 2019-12-03 At&T Intellectual Property I, L.P. Apparatus for configuring a surface of an antenna
US10225025B2 (en) 2016-11-03 2019-03-05 At&T Intellectual Property I, L.P. Method and apparatus for detecting a fault in a communication system
US10224634B2 (en) 2016-11-03 2019-03-05 At&T Intellectual Property I, L.P. Methods and apparatus for adjusting an operational characteristic of an antenna
US10340601B2 (en) 2016-11-23 2019-07-02 At&T Intellectual Property I, L.P. Multi-antenna system and methods for use therewith
US10178445B2 (en) 2016-11-23 2019-01-08 At&T Intellectual Property I, L.P. Methods, devices, and systems for load balancing between a plurality of waveguides
US10340603B2 (en) 2016-11-23 2019-07-02 At&T Intellectual Property I, L.P. Antenna system having shielded structural configurations for assembly
US10090594B2 (en) 2016-11-23 2018-10-02 At&T Intellectual Property I, L.P. Antenna system having structural configurations for assembly
US10535928B2 (en) 2016-11-23 2020-01-14 At&T Intellectual Property I, L.P. Antenna system and methods for use therewith
US10305190B2 (en) 2016-12-01 2019-05-28 At&T Intellectual Property I, L.P. Reflecting dielectric antenna system and methods for use therewith
US10361489B2 (en) 2016-12-01 2019-07-23 At&T Intellectual Property I, L.P. Dielectric dish antenna system and methods for use therewith
US10727599B2 (en) 2016-12-06 2020-07-28 At&T Intellectual Property I, L.P. Launcher with slot antenna and methods for use therewith
US9927517B1 (en) 2016-12-06 2018-03-27 At&T Intellectual Property I, L.P. Apparatus and methods for sensing rainfall
US10135145B2 (en) 2016-12-06 2018-11-20 At&T Intellectual Property I, L.P. Apparatus and methods for generating an electromagnetic wave along a transmission medium
US10819035B2 (en) 2016-12-06 2020-10-27 At&T Intellectual Property I, L.P. Launcher with helical antenna and methods for use therewith
US10694379B2 (en) 2016-12-06 2020-06-23 At&T Intellectual Property I, L.P. Waveguide system with device-based authentication and methods for use therewith
US10439675B2 (en) 2016-12-06 2019-10-08 At&T Intellectual Property I, L.P. Method and apparatus for repeating guided wave communication signals
US10755542B2 (en) 2016-12-06 2020-08-25 At&T Intellectual Property I, L.P. Method and apparatus for surveillance via guided wave communication
US10637149B2 (en) 2016-12-06 2020-04-28 At&T Intellectual Property I, L.P. Injection molded dielectric antenna and methods for use therewith
US10020844B2 (en) 2016-12-06 2018-07-10 T&T Intellectual Property I, L.P. Method and apparatus for broadcast communication via guided waves
US10326494B2 (en) 2016-12-06 2019-06-18 At&T Intellectual Property I, L.P. Apparatus for measurement de-embedding and methods for use therewith
US10382976B2 (en) 2016-12-06 2019-08-13 At&T Intellectual Property I, L.P. Method and apparatus for managing wireless communications based on communication paths and network device positions
US9893795B1 (en) 2016-12-07 2018-02-13 At&T Intellectual Property I, Lp Method and repeater for broadband distribution
US10027397B2 (en) 2016-12-07 2018-07-17 At&T Intellectual Property I, L.P. Distributed antenna system and methods for use therewith
US10168695B2 (en) 2016-12-07 2019-01-01 At&T Intellectual Property I, L.P. Method and apparatus for controlling an unmanned aircraft
US10389029B2 (en) 2016-12-07 2019-08-20 At&T Intellectual Property I, L.P. Multi-feed dielectric antenna system with core selection and methods for use therewith
US10547348B2 (en) 2016-12-07 2020-01-28 At&T Intellectual Property I, L.P. Method and apparatus for switching transmission mediums in a communication system
US10139820B2 (en) 2016-12-07 2018-11-27 At&T Intellectual Property I, L.P. Method and apparatus for deploying equipment of a communication system
US10446936B2 (en) 2016-12-07 2019-10-15 At&T Intellectual Property I, L.P. Multi-feed dielectric antenna system and methods for use therewith
US10359749B2 (en) 2016-12-07 2019-07-23 At&T Intellectual Property I, L.P. Method and apparatus for utilities management via guided wave communication
US10243270B2 (en) 2016-12-07 2019-03-26 At&T Intellectual Property I, L.P. Beam adaptive multi-feed dielectric antenna system and methods for use therewith
US10389037B2 (en) 2016-12-08 2019-08-20 At&T Intellectual Property I, L.P. Apparatus and methods for selecting sections of an antenna array and use therewith
US10916969B2 (en) 2016-12-08 2021-02-09 At&T Intellectual Property I, L.P. Method and apparatus for providing power using an inductive coupling
US10411356B2 (en) 2016-12-08 2019-09-10 At&T Intellectual Property I, L.P. Apparatus and methods for selectively targeting communication devices with an antenna array
US10069535B2 (en) 2016-12-08 2018-09-04 At&T Intellectual Property I, L.P. Apparatus and methods for launching electromagnetic waves having a certain electric field structure
US10777873B2 (en) 2016-12-08 2020-09-15 At&T Intellectual Property I, L.P. Method and apparatus for mounting network devices
US10938108B2 (en) 2016-12-08 2021-03-02 At&T Intellectual Property I, L.P. Frequency selective multi-feed dielectric antenna system and methods for use therewith
US10326689B2 (en) 2016-12-08 2019-06-18 At&T Intellectual Property I, L.P. Method and system for providing alternative communication paths
US9911020B1 (en) 2016-12-08 2018-03-06 At&T Intellectual Property I, L.P. Method and apparatus for tracking via a radio frequency identification device
US10103422B2 (en) 2016-12-08 2018-10-16 At&T Intellectual Property I, L.P. Method and apparatus for mounting network devices
US10601494B2 (en) 2016-12-08 2020-03-24 At&T Intellectual Property I, L.P. Dual-band communication device and method for use therewith
US10530505B2 (en) 2016-12-08 2020-01-07 At&T Intellectual Property I, L.P. Apparatus and methods for launching electromagnetic waves along a transmission medium
US9998870B1 (en) 2016-12-08 2018-06-12 At&T Intellectual Property I, L.P. Method and apparatus for proximity sensing
US10340983B2 (en) 2016-12-09 2019-07-02 At&T Intellectual Property I, L.P. Method and apparatus for surveying remote sites via guided wave communications
US9838896B1 (en) 2016-12-09 2017-12-05 At&T Intellectual Property I, L.P. Method and apparatus for assessing network coverage
US10264586B2 (en) 2016-12-09 2019-04-16 At&T Mobility Ii Llc Cloud-based packet controller and methods for use therewith
CN110168393B (zh) * 2017-01-13 2021-08-20 西门子医疗有限公司 低磁场强度下运行的磁共振断层成像设备和局部线圈矩阵
US9973940B1 (en) 2017-02-27 2018-05-15 At&T Intellectual Property I, L.P. Apparatus and methods for dynamic impedance matching of a guided wave launcher
US10298293B2 (en) 2017-03-13 2019-05-21 At&T Intellectual Property I, L.P. Apparatus of communication utilizing wireless network devices
US10794970B2 (en) 2017-07-10 2020-10-06 General Electric Company Staggered parallel transmission radio frequency coil for magnetic resonance imaging
JP7250476B2 (ja) * 2017-11-08 2023-04-03 キヤノンメディカルシステムズ株式会社 磁気共鳴イメージング装置及びｒｆコイル
EP3527999B1 (de) * 2018-02-16 2024-03-27 Siemens Healthineers AG Sendeantenne für eine magnetresonanzeinrichtung
CN113767295B (zh) * 2019-02-22 2023-02-17 普罗马克索公司 可变调谐的伪鸟笼线圈及其应用
US11428765B2 (en) * 2019-11-05 2022-08-30 Quality Electrodynamics, Llc MRI head coil comprising an open shield
KR102633694B1 (ko) * 2021-11-30 2024-02-07 가천대학교 산학협력단 자기공명영상용 rf 코일

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0498539A1 (en) * 1991-02-06 1992-08-12 Picker International, Inc. Magnetic resonance apparatus
US20040227515A1 (en) * 2003-02-19 2004-11-18 Jurgen Nistler Radio-frequency antenna for a magnetic resonance system
WO2006120588A1 (en) * 2005-05-06 2006-11-16 Koninklijke Philips Electronics, N.V. Electromagnetic shielding for high field mri coils
CN1882847A (zh) * 2003-11-18 2006-12-20 皇家飞利浦电子股份有限公司 用于超高场(shf)mri的rf线圈系统

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3133432A1 (de) 1981-08-24 1983-03-03 Siemens AG, 1000 Berlin und 8000 München Hochfrequenzfeld-einrichtung in einer kernspinresonanz-apparatur
US4782298A (en) * 1987-09-01 1988-11-01 The Regents Of The University Of California MRI QD RF coil having diode switched detuning circuit producing reduced artifact
US5510714A (en) 1991-08-09 1996-04-23 Hitachi, Ltd. Magnetic resonance imaging apparatus and RF coil employed therein
DE69221835T2 (de) 1991-12-11 1998-03-05 Philips Electronics Nv Magnetresonanzgerät mit einer Vogelkäfig-RF-Spule
JP3694558B2 (ja) * 1996-01-29 2005-09-14 株式会社日立メディコ 高周波コイル及びそれを用いた磁気共鳴検査装置
US6344745B1 (en) * 1998-11-25 2002-02-05 Medrad, Inc. Tapered birdcage resonator for improved homogeneity in MRI
US6313633B1 (en) * 1999-12-27 2001-11-06 General Electric Company Magnetic resonance imaging head coil
DE10261214B4 (de) * 2002-02-19 2006-04-13 Siemens Ag Hochfrequenzantenne für eine Magnetresonanzanlage
US6781378B2 (en) 2002-02-19 2004-08-24 Siemens Aktiengesellschaft Radio-frequency antenna for a magnetic resonance system
US7084629B2 (en) * 2002-11-27 2006-08-01 Medrad, Inc. Parallel imaging compatible birdcage resonator
US7084630B2 (en) * 2004-01-28 2006-08-01 Worcester Polytechnic Institute Multi-modal RF coil for magnetic resonance imaging
US7227360B2 (en) 2005-01-14 2007-06-05 Invivo Corporation Phased array MRI coil with controllable coupled ring resonator
US7508212B2 (en) * 2007-03-22 2009-03-24 Wisconsin Alumni Research Foundation RF coil assembly and method for practicing magnetization transfer on magnetic resonance imaging and spectroscopy systems
JP2011500193A (ja) * 2007-10-17 2011-01-06 コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ 改善された均一性及び減少したｓａｒを備えるバードケージコイル

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0498539A1 (en) * 1991-02-06 1992-08-12 Picker International, Inc. Magnetic resonance apparatus
US20040227515A1 (en) * 2003-02-19 2004-11-18 Jurgen Nistler Radio-frequency antenna for a magnetic resonance system
CN1882847A (zh) * 2003-11-18 2006-12-20 皇家飞利浦电子股份有限公司 用于超高场(shf)mri的rf线圈系统
WO2006120588A1 (en) * 2005-05-06 2006-11-16 Koninklijke Philips Electronics, N.V. Electromagnetic shielding for high field mri coils

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CN101548193A (zh) 2009-09-30
DE102007016312B4 (de) 2010-06-17
US20090267606A1 (en) 2009-10-29
US7990146B2 (en) 2011-08-02
WO2008122553A1 (de) 2008-10-16

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