Electronics for a high temperature superconducting receiver system for magnetic resonance microimaging.

We describe an MRI (magnetic resonance imaging) receiver system that incorporates a high temperature superconducting (HTS) resonator as a surface coil. Techniques for measuring the Q of the HTS resonator in a 7 Tesla field are discussed. A method for coupling a room temperature copper resonant circuit to the HTS element is covered, and it is shown that such a coupling scheme preserves the signal-to-noise (SNR) gain afforded by the HTS coil. A preamplifier with a noise figure (NF) of < 0.15 dB at 300 MHz is described.