摘要:
A receiving device for an MRI (magnetic resonance imaging) system has multiple receiving coils. In the same imaging acceleration direction, a junction region is formed between adjacent receiving coils. An additional receiving coil is arranged on the junction region. The additional receiving coil covers at least partially a line of strong phase variation in sensitivity at the boundary of said junction region. This receiving device alleviates the problem of poor sensitivity to MRI signals in the junction region in the imaging acceleration direction, so as to improve the imaging quality in the junction region, and thus improving the overall imaging quality.
摘要:
A receiving device for an MRI (magnetic resonance imaging) system has multiple receiving coils. In the same imaging acceleration direction, a junction region is formed between adjacent receiving coils. An additional receiving coil is arranged on the junction region. The additional receiving coil covers at least partially a line of strong phase variation in sensitivity at the boundary of said junction region. This receiving device alleviates the problem of poor sensitivity to MRI signals in the junction region in the imaging acceleration direction, so as to improve the imaging quality in the junction region, and thus improving the overall imaging quality.
摘要:
In a method for processing radio frequency signals of a magnetic resonance imaging system in which the coil portion of the magnetic resonance imaging system includes a body coil and a local coil, radio frequency signals are supplied to the body coil, and these radio frequency signals are coupled to said local coil, and transmitted by said local coil into a region to be examined. A corresponding radio frequency system has a local coil and a body coil, with power coupling between the local coil and the body coil; during the phase for transmitting the radio frequency signals. The body coil serves to couple the radio frequency signals to be transmitted to the local coil, and the local coil serves to transmit the coupled radio frequency signals to a region to be examined. This method and system allow the transmitting function of the local coil to be achieved without having a coil plug on a patient bed to provide a radio frequency signal transmitting channel.
摘要:
A transmission circuit for radio frequency signals has a power mixer and includes a radio frequency input port, a first radio frequency output port, a second radio frequency output port, and a dummy load port. The transmission circuit also has a first switch unit and a second switch unit. The first switch unit is connected to the first radio frequency output port and outputs the radio frequency signals which are emitted from the first radio frequency output port or reflects the radio frequency signals which are emitted from the first radio frequency output port back to the first radio frequency output port. The second switch unit is connected to the second radio frequency output port and outputs the radio frequency signals which are emitted from the second radio frequency output port, or reflects the radio frequency signals which are emitted from the second radio frequency output port back to the second radio frequency output port. The radio frequency signals reflected to the radio frequency input port by the first switch unit and the radio frequency signals reflected to said radio frequency input port by the second switch unit cancel each other. The transmission circuit has reduced complexity and cost.
摘要:
A body coil assembly for a magnetic resonance apparatus has a first coil and a second coil for generating a radio-frequency field in space, and a power control apparatus connected to the first coil and the second coil for controlling the transmitting power of the first coil and the second coil. In a method for generating a radio-frequency field using such a body coil assembly, the transmitting powers of the first coil and the second coil are controlled, to provide unequal transmitting powers to the first coil and the second coil when needed to generate a required radio-frequency field distribution, so as to form a stronger field strength at a certain position, thus improving the signal to noise ratio at that position during the receiving process.
摘要:
A radio frequency (RF) switch device has at least two RF switch units, each RF switch unit having an output terminal and at least two input terminals. The RF switch units select one channel of RF signals from several channels of the RF signals that are supplied as inputs to their input terminals for emission as an output from their output terminals. A magnetic resonance imaging system and an RF signal transmission method employ such an RF switch device. The use of such an RF switch device reduces the number of channels of the RF signals that need to be further transmitted, which in turn reduces the number of the corresponding long RF cable channels and the number of channels of the subsequent devices, thereby preventing waste and reducing the cost of the system. Moreover, if the subsequent devices include a receiver coil channel selector, then the complexity of the receiver coil channel selector will also be reduced as the number of RF signal channels is decreased.
摘要:
In a method for processing radio frequency signals of a magnetic resonance imaging system in which the coil portion of the magnetic resonance imaging system includes a body coil and a local coil, radio frequency signals are supplied to the body coil, and these radio frequency signals are coupled to said local coil, and transmitted by said local coil into a region to be examined. A corresponding radio frequency system has a local coil and a body coil, with power coupling between the local coil and the body coil; during the phase for transmitting the radio frequency signals. The body coil serves to couple the radio frequency signals to be transmitted to the local coil, and the local coil serves to transmit the coupled radio frequency signals to a region to be examined. This method and system allow the transmitting function of the local coil to be achieved without having a coil plug on a patient bed to provide a radio frequency signal transmitting channel.
摘要:
A transmission circuit for radio frequency signals has a power mixer and includes a radio frequency input port, a first radio frequency output port, a second radio frequency output port, and a dummy load port. The transmission circuit also has a first switch unit and a second switch unit. The first switch unit is connected to the first radio frequency output port and outputs the radio frequency signals which are emitted from the first radio frequency output port or reflects the radio frequency signals which are emitted from the first radio frequency output port back to the first radio frequency output port. The second switch unit is connected to the second radio frequency output port and outputs the radio frequency signals which are emitted from the second radio frequency output port, or reflects the radio frequency signals which are emitted from the second radio frequency output port back to the second radio frequency output port. The radio frequency signals reflected to the radio frequency input port by the first switch unit and the radio frequency signals reflected to said radio frequency input port by the second switch unit cancel each other. The transmission circuit has reduced complexity and cost.
摘要:
A radio frequency (RF) switch device has at least two RF switch units, each RF switch unit having an output terminal and at least two input terminals. The RF switch units select one channel of RF signals from several channels of the RF signals that are supplied as inputs to their input terminals for emission as an output from their output terminals. A magnetic resonance imaging system and an RF signal transmission method employ such an RF switch device. The use of such an RF switch device reduces the number of channels of the RF signals that need to be further transmitted, which in turn reduces the number of the corresponding long RF cable channels and the number of channels of the subsequent devices, thereby preventing waste and reducing the cost of the system. Moreover, if the subsequent devices include a receiver coil channel selector, then the complexity of the receiver coil channel selector will also be reduced as the number of RF signal channels is decreased.
摘要:
A receiver coil array for a magnetic resonance imaging system has an inductive coupling coil incorporated in the middle coil unit of the receiver coil array as its secondary coil, which serves to regulate the frequency and impedance of the middle coil unit. The secondary coil has an output regulation circuit which can output the magnetic resonance signals received by the middle coil unit to increase the number of the coil units in the receiver coil array that receive and output resonance signals while further regulating the frequency and impedance of the middle coil unit. Since this receiver coil array achieves regulation of the frequency and impedance of the middle coil unit and increases the number of the coil units in the receiver coil array that receive and output the resonance signals, it can improve the quality of the signals received by the receiver coil array. Moreover, the design is simple and is easy to achieve.