低场磁共振成像仪射频收发线圈研制电子与通信工程专业论文.docxVIP

AbstractMagnetic Abstract Magnetic resonance imaging(MRI)in nowadays is an important medical imaging technology,and it is widely used at clinic．RF coil is used for transmitting and receiving radio frequency signals in MR／and is an important part of MR／system and is an extreme important component for the image quality．RF coil system horizontal field of low field magnetic resonance imaging apparatus of the RF coil structure and high field magnetic resonance equipment used in the main magnetic field due to the different directions there are significant differences．Vertical field design difficulty RF transmit coil is relatively large．Phased-array coil can be larger imaging area also has a high signal to noise ratio．And phased—array coil Can also be used for parallel imaging technology to improve imaging speed．Domestic research on low．field open MRI RF transmitter coil and phased·array coil technology is in small numbers．the study of low field MRI RF coil technology is of great significance． Based on magnetic resonance imaging system in the RF coil and the related technology，a radio frequency transmits and receive coils are designed for 0．5T open permanent magnet imaging system．Two types of RF transmit coils are designed： circular planer and rectangular strip planar transmit coils，both of them developed to satisfy the open space requirements．Using CST software transmit coil simulation analysis，and after the actual test and imaging experiments，the results show that both the transmitter coil Can achieve good imaging results．we designed a decoupling circuit for cylinder surface received arrays．We connected every two arrays with an inductor,a connecting ground line is also plased between the coils to provide a common reference point．A four-channel RF receive coil Was made for 0．5T MRI system，experimental results show that there are good isolation(-1 9dB--_，-32dB) between coil elements and good decoupling effect Can be achieved． Key words：magnetic resonance imaging，RF tra