# US 11,896,359 B2 · Multi-channel magnetic resonance imaging RF coil > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,896,359 B2 - Document ID: US11896359B2 - Status: Granted - Kind: B2 - Application number: 16/962,244 - Filed: 2019-01-15 - Published: 2021-03-04 - Granted: 2024-02-13 - Earliest claimed: 2018-01-18 - Assignees: Koninklijke Philips N.V. - Applicants: Koninklijke Philips N.V. - Inventors: Christoph Leussler; Ingo Schmale - Web page: https://patentgrep.com/patent/US11896359B2 ## CPC - G01R 33/3607: {RF waveform generators, e.g. frequency generators, amplitude-, frequency- or phase modulators or shifters, pulse programmers, digital to analog converters for the RF signal, means for filtering or attenuating of the RF signal} - G01R 33/34076: {Birdcage coils} - G01R 33/3678: {involving quadrature drive or detection, e.g. a circularly polarized RF magnetic field} - G01R 33/5659: {caused by a distortion of the RF magnetic field, e.g. spatial inhomogeneities of the RF magnetic field (G01R33/56509, G01R33/56518, G01R33/56536 take precedence)} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract The present disclosure relates to a multi-channel magnetic resonance imaging RF coil (114) with at least four channels and comprising a coil element for each of the channels, the RF coil (114) further comprising for each coil element a socket (300-306) that is electrically coupled to said coil element via a respective first transmission line (209), each socket (300-306) being adapted for receiving a plug for providing an RF signal via the respective first transmission line (209) to the respective coil element, wherein with respect to a predefined RF signal the differences in electrical length between any of the transmission lines is kλ/4 where k is an integer and λ is the wavelength of the RF signal. ## Claims ### Claim 1 A multi-channel magnetic resonance imaging radio frequency (RF) coil with at least four channels, the RF coil comprising: a coil element for each of the channels; and a socket corresponding to each coil element, wherein the socket is electrically coupled to said corresponding coil element via a respective first transmission line, each socket being adapted for receiving a plug for providing an RF signal via the respective first transmission line to the corresponding coil element, wherein with respect to a predefined RF signal differences in electrical length between any of the first transmission lines are kλ/4 resulting in a predefined phase relationship at the sockets, where k is an integer and λ is the wavelength of the RF signal, the RF coil being configured to be driven at the wavelength of the RF signal, wherein the RF coil has four channels with two pairs of the first transmission lines, wherein within each pair the first transmission lines are of the same electrical length as each other, and wherein the differences in electrical length between the first transmission lines of the two pairs is λ/4. ### Claim 2 (depends on 1) The coil of claim 1, wherein k is an integer multiple of 4. ### Claim 3 (depends on 1) The coil of claim 1, each first transmission line comprising an impedance matching network and a first phase shifting circuit directly attached to the impedance matching network, wherein for each first transmission line the respective first phase shifting circuit is adapted for providing a compensation of the length of the respective first transmission line as determined in between its socket and its first phase shifting circuit such that said differences in electrical length between any of the first transmission lines is kλ/4. ### Claim 4 (depends on 3) The coil of claim 3, the first phase shifting circuit being one of a second transmission line and a lumped element phase shifter. ### Claim 5 (depends on 3) The coil of claim 3, the impedance matching network being immediately connected to the corresponding coil element. ### Claim 6 (depends on 1) The coil of claim 1, the sockets being integrated in a housing of the RF coil. ### Claim 7 (depends on 6) The coil of claim 6, further comprising a terminal board, the terminal board comprising the sockets, the terminal board being integrated in the housing of the RF coil). ### Claim 8 (depends on 7) The coil of claim 7, each first transmission line comprising a ground wire, wherein all the ground wires of all the first transmission lines are connected to a common ground at the terminal board. ### Claim 9 (depends on 3) The coil of claim 3, each first transmission line comprising a second phase shifting circuit and a socket connector, the socket connector electrically connecting the corresponding coil element with its socket, each second phase shifting circuit electrically connecting the respective socket connector to the respective socket, wherein for each first transmission line the respective second phase shifting circuit is adapted for providing a compensation of the length of the respective first transmission line as determined in between its coil element and its socket connector such that said differences in electrical length between any of the first transmission lines is kλ/4, wherein the second phase shifting circuits and the socket connectors are mounted to the terminal board or the housing of the RF coil. ### Claim 10 (depends on 1) The coil of claim 1, the coil being an RF body coil. ### Claim 11 (depends on 1) A magnetic resonance imaging system for acquiring magnetic resonance data, the magnetic resonance system comprising: a main magnet for generating a main magnetic field within an imaging zone, the multi-channel magnetic resonance imaging RF coil of claim 1, and associated to each channel an RF source for supplying radio-frequency power to the RF coil via the socket associated to the respective channel for driving the RF coil. ### Claim 12 (depends on 11) The system of claim 11, wherein each RF source comprises a respective connection point for the supplying of the RF power, the system further comprising a cable for each RF source, the cable electrically connecting the respective connection point of the RF source with the socket associated to the RF source, the cable having a plug for being received by the respective socket, wherein with regard to the wavelength all the cables electrically connecting the connection points of the RF sources with the sockets have differences in electrical length between any other cable of nλ/4, where n is an integer. ### Claim 13 (depends on 12) The system of claim 12, wherein n equals zero. ### Claim 14 (depends on 11) The system of claim 11, wherein k is an integer multiple of 4. ### Claim 15 (depends on 11) The system of claim 11, each first transmission line comprising an impedance matching network and a first phase shifting circuit directly attached to the impedance matching network, wherein for each first transmission line the respective first phase shifting circuit is adapted for providing a compensation of the length of the respective first transmission line as determined in between its socket and its first phase shifting circuit such that said differences in electrical length between any of the first transmission lines is kλ/4. ### Claim 16 (depends on 15) The system of claim 15, the first phase shifting circuit being one of a second transmission line and a lumped element phase shifter. ### Claim 17 (depends on 15) The system of claim 15, each first transmission line comprising a second phase shifting circuit and a socket connector, the socket connector electrically connecting the corresponding coil element with its socket, each second phase shifting circuit electrically connecting the respective socket connector to the respective socket, wherein for each first transmission line the respective second phase shifting circuit is adapted for providing a compensation of the length of the respective first transmission line as determined in between its coil element and its socket connector such that said differences in electrical length between any of the first transmission lines is kλ/4, wherein the second phase shifting circuits and the socket connectors are mounted to the terminal board or the housing of the RF coil. ### Claim 18 A method of servicing a magnetic resonance imaging (MRI) system, the method comprising: providing a multi-channel magnetic resonance imaging radio frequency (RF) coil, wherein the RF coil has at least four channels, the RF coil being adapted for picking up magnetic resonance signals from an imaging zone of the MRI system, the RF coil including a coil element for each of the channels a socket corresponding to each coil element, wherein the socket is electrically coupled to said corresponding coil element via a respective first transmission line, each socket being adapted for receiving a plug for providing an RF signal via the respective first transmission line to the corresponding coil element, wherein with respect to a predefined RF signal the differences in electrical length between any of the transmission lines are kλ/4, where k is an integer and λ is the wavelength of the RF signal, the RF coil being configured to be driven at the wavelength of the RF signal, wherein the RF coil has four channels with two pairs of the first transmission lines, wherein within each pair the first transmission lines are of the same electrical length as each other, and wherein the differences in electrical length between the first transmission lines of the two pairs is λ/4, wherein the MRI system includes a plurality of RF sources, wherein the RF sources are each associated to an associated one of the channels for supplying radio-frequency power to the RF coil via the socket associated to the corresponding channel, for driving the RF coil, electrically connecting the RF sources to the respective sockets with electrical cables, wherein with regard to the wavelength all the cables have differences in electrical length between any other cable of nλ/4, where n is an integer resulting in a predefined phase relationship at the sockets; and acquiring magnetic resonance (MR) data by operating the MRI system in a prescribed manner to obtain data for servicing the MRI system. ### Claim 19 (depends on 18) The method of claim 18, wherein k is an integer multiple of 4. ### Claim 20 (depends on 18) The method of claim 18, each first transmission line comprising an impedance matching network and a first phase shifting circuit directly attached to the impedance matching network, wherein for each first transmission line the respective first phase shifting circuit is adapted for providing a compensation of the length of the respective first transmission line as determined in between its socket and its first phase shifting circuit such that said differences in electrical length between any of the first transmission lines is kλ/4.