具有新型保护电路的磁共振接收线圈研制

摘要

The low input impedance preamplifier is widely used in the design of MRI RF coil.The protection of the preamplifier becomes the key of the coil circuits.This paper develops a MRI receiving coil with new protecting circuit.The power of the preamplifier is controlled by the detune signal and a high impedance circuit is placed between resonance circuit and preamplifier to protect the input of the preamplifier.The results of test show that all port of the coil circuit runs stably.This design could also be used in the loop array and it has the enlightening significance to the design of the MRI RF coil.%低输入阻抗前置放大器在磁共振成像接收线圈中的广泛使用,使得对前置放大器的保护成为接收线圈设计的重点.文中设计制作了带有新型保护电路的磁共振接收线圈,使用失谐信号作为触发信号控制前置放大器电源的开断,并在线圈谐振回路和前置放大器之间产生高阻状态以保护前置放大器输入端.测试结果表明,各部分电路可稳定工作.该电路可用于多通道接收线圈并对于磁共振线圈的设计有启发意义.