Abstract: A radio-frequency antenna for acquisition of a magnetic resonance signal has two electrodes that are connected with one another via a discrete tuning device. The first radio-frequency antenna) is tuned to a resonance frequency by the tuning device. The tuning device has a first tuning element influencing the resonance frequency of the radio-frequency antenna and a second tuning element influencing the resonance frequency of the first radio-frequency antenna. The tuning elements are connected in series and fashioned as inductors. The radio-frequency antenna also has two tap points at which an acquisition signal representative of the acquired magnetic resonance signal is tapped and conducted away via feed lines. The tap points are respectively arranged between the electrodes and the tuning element and one of said tap points is between the first and second tuning elements.

Abstract: A coaxial cable comprises at least one internal conductor and a surrounding cable shield. A plurality of sheath wave barriers are arranged along the cable shield, each having two ends that are coupled to the cable shield at coupling points of the cable shield that are spaced from one another. The coaxial cable is exposed to a radio-frequency excitation field with an excitation frequency, due to which sheath waves can be excited on the cable shield. The excitation field is shielded from the at least one internal conductor via the cable shield. The sheath waves can be damped via the sheath wave barriers. A detection circuit is associated with at least one of the sheath wave barriers, from which detection circuit a measurement signal characteristic of a load of the respective sheath wave barrier due to the excitation field can be generated. The measurement signal can be tapped and evaluated.

Abstract: A sheath wave barrier unit for an outer shielding of a coaxial cable that also has an inner conductor, has two sheath wave barriers that damp or suppress sheath waves that are induced in two series conductor segments of the outer shielding. Each sheath wave barrier forms a resonant oscillating circuit at a predetermined high frequency, with the high frequency being the same for both sheath wave barriers. The sheath wave barrier unit has a shielding device with at least one radial shield by means of which the sheath wave barriers are decoupled from one another. The sheath wave barriers and the shielding device are arranged on a common carrier.

Abstract: A coil arrangement for a magnetic resonance apparatus has a number of coil elements that are capable of being operated independently of one another and are situated around a common central area. Each coil element of the coil arrangement is capacitively or inductively decoupled from the coil elements of the coil arrangement that are immediately adjacent to this coil element. In the central area, there is situated a capacitor network that connects the coil elements of the coil arrangement to one another. The capacitor network is fashioned and dimensioned such that it at least reduces the coupling of each coil element of the coil arrangement to at least one additional coil element of the coil arrangement that is not immediately adjacent to the respective coil element.

Abstract: A detuning circuit unit for antennas of a magnetic resonance apparatus has at least two identical detuning modules that are connected in a cascade circuit and can be simultaneously activated with a control signal of a control signal source, and a circuit component to terminate a last of the detuning modules of the cascade circuit. An advantage is in the modular and cascadable use of the identical detuning modules, such that PIN diodes used as radio frequency switches are serially fed current in a first operating state and are supplied in parallel with a blocking voltage in a second operating state.

Abstract: An antenna arrangement for acquisition of a magnetic resonance signal has at least two acquisition antennas, each having at least one conductor loop and each conductor loop having an interruption therein. The conductor loops are connected in parallel at the interruptions and a capacitive decoupling element is arranged in at least one of the interruptions. The acquisition antennas are connected with one another via at least two capacitive blocking elements, and all capacitive blocking elements and all capacitive decoupling elements together exhibit a capacitance at which the acquisition antennas are decoupled from one another. The acquisition antennas are connected with one another via an inductive element that is connected in parallel with the capacitive blocking elements. The inductive element exhibits an inductance at which a common mode signal between the acquisition antennas is suppressed.

Abstract: An antenna arrangement for a magnetic resonance device has a first antenna group, which includes at least one antenna element, and a second antenna group separated from the first antenna group, which likewise includes at least one antenna element. The antenna groups have respective cooperating coupler antenna parts that are fashioned and/or arranged such that, given a specific adjacent arrangement of the antenna groups with respect to one another, the coupler antenna parts form, by inductive coupling, a common boundary antenna element of the two antenna groups, which is inductively decoupled from the further antenna elements within the appertaining antenna groups. A corresponding method for coupling two antenna groups separated from one another employs such an antenna arrangement.

Abstract: A reception unit for an MR device with at least two local antennas has a combination network to which the antennas are connected separately for combination of the antenna signals. The combination network generates at least two different modes that are linear combinations of the antenna signals, and at least two of which are present at an output of the combination network.

Abstract: In an antenna selector switch and a switching method, a number of antenna units of a magnetic resonance apparatus can be operated via one RF channel. The antenna selector switch has at least two antenna connectors for connection with one antenna unit. A first of the antenna units can be set in terms of its resonance frequency via a control signal. The selector switch also has an RF channel connector for making a connection with a radio frequency unit of the magnetic resonance apparatus; and a switching unit to make a radio frequency connection between one of the antenna connectors and the RF channel connector. The switching unit can activated with the control signal. This allows a reduction of the necessary reception channels without additional control signal lines.

Abstract: An antenna arrangement for acquisition of a magnetic resonance signal has at least two acquisition antennas, each having at least one conductor loop and each conductor loop having an interruption therein. The conductor loops are connected in parallel at the interruptions and a capacitive decoupling element is arranged in at least one of the interruptions. The acquisition antennas are connected with one another via at least two capacitive blocking elements, and all capacitive blocking elements and all capacitive decoupling elements together exhibit a capacitance at which the acquisition antennas are decoupled from one another. The acquisition antennas are connected with one another via an inductive element that is connected in parallel with the capacitive blocking elements. The inductive element exhibits an inductance at which a common mode signal between the acquisition antennas is suppressed.

Abstract: A sheath wave barrier unit for an outer shielding of a coaxial cable that also has an inner conductor, has two sheath wave barriers that damp or suppress sheath waves that are induced in two series conductor segments of the outer shielding. Each sheath wave barrier forms a resonant oscillating circuit at a predetermined high frequency, with the high frequency being the same for both sheath wave barriers. The sheath wave barrier unit has a shielding device with at least one radial shield by means of which the sheath wave barriers are decoupled from one another. The sheath wave barriers and the shielding device are arranged on a common carrier.

Abstract: In a method and apparatus for suppression of artifacts in MRT imaging, individual signals are acquired at a first spatial point and at a second spatial point by a number of coils of a coil array. A combined signal composed of at least the individual signals of the first and second points is calculated using coil-dependent weighting factors for the individual signals and. Boundary conditions are established for the calculation of the combined signal such that an artifact is suppressed in the second point.

Abstract: In an antenna selector switch and a switching method, a number of antenna units of a magnetic resonance apparatus can be operated via one RF channel. The antenna selector switch has at least two antenna connectors for connection with one antenna unit. A first of the antenna units can be set in terms of its resonance frequency via a control signal. The selector switch also has an RF channel connector for making a connection with a radio frequency unit of the magnetic resonance apparatus; and a switching unit to make a radio frequency connection between one of the antenna connectors and the RF channel connector. The switching unit can activated with the control signal. This allows a reduction of the necessary reception channels without additional control signal lines.

Abstract: A detuning circuit unit for antennas of a magnetic resonance apparatus has at least two identical detuning modules that are connected in a cascade circuit and can be simultaneously activated with a control signal of a control signal source, and a circuit component to terminate a last of the detuning modules of the cascade circuit. An advantage is in the modular and cascadable use of the identical detuning modules, such that PIN diodes used as radio frequency switches are serially fed current in a first operating state and are supplied in parallel with a blocking voltage in a second operating state.

Abstract: An electrically conductive inside structure of a standing wave barrier surrounds a section of a conductor in a sub-region. It can be displaceably arranged on the conductor section and galvanically separated from it but can be inductively coupled to it. A basic wave trap surrounds the inside structure on a part of its length. It is galvanically connected to the inside structure and to a capacitor. The capacitor is galvanically connected to the inside structure.

Abstract: High-frequency coil arrangement for a magnetic resonance tomography apparatus and magnetic resonance tomography apparatus employing such an arrangement have a surface coil and a loop coil for enclosing the examination subject. Both coils are fashioned for receiving the same first polarization component. A switching device is present for alternately deactivating and/or activating the surface coil and the loop coil. The two coils are preferably arranged on a common carrier structure that is bendable.

Abstract: A reception unit for an MR device with at least two local antennas has a combination network to which the antennas are connected separately for combination of the antenna signals. The combination network generates at least two different modes that are linear combinations of the antenna signals, and at least two of which are present at an output of the combination network.

Abstract: In an antenna arrangement for an magnetic resonance device and a method for acquiring magnetic resonance signals, at least two adjacent individual antennas are provided and a galvanically contact-free decoupling coil is fashioned and/or arranged such that it inductively couples with both adjacent individual antennas so that the inductive coupling is minimal between the two adjacent individual antennas.

Abstract: An antenna arrangement for a magnetic resonance device has a first antenna group, which includes at least one antenna element, and a second antenna group separated from the first antenna group, which likewise includes at least one antenna element. The antenna groups have respective cooperating coupler antenna parts that are fashioned and/or arranged such that, given a specific adjacent arrangement of the antenna groups with respect to one another, the coupler antenna parts form, by inductive coupling, a common boundary antenna element of the two antenna groups, which is inductively decoupled from the further antenna elements within the appertaining antenna groups. A corresponding method for coupling two antenna groups separated from one another employs such an antenna arrangement.

Abstract: An electrostatic relay is employed for switching in an electrical line system of a magnetic resonance tomography apparatus. The relay is employed for detuning a radio-frequency reception coil during a radio-frequency transmission phase of the nuclear magnetic resonance tomography apparatus.