Implications of HTS Film Linearity on RF Coil Design and Assessment at 9.4 T
نویسندگان
چکیده
INTRODUCTION High-temperature superconducting (HTS) Helmholtz coil pairs have been shown to provide substantial increases in signal-to-noise ratio (SNR) for applications in NMR and MR microscopy (1, 2). One limitation of HTS coils is that their non-linear response to applied power produces distortion of shaped RF pulses (3). Through the use of a previously reported field mapping technique (4) modified for application to high field microscopy, we have developed a simple method for measuring coil linearity. In addition, this technique has provided insight into RF pulse behavior in the presence of off-resonance effects.
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