An Automated Cartesian Feedback Transceiver for Use in High Magnetic Fields

David Ian Hoult¹, Glen Kolansky¹, Derek Foreman¹, John Rendell¹, Mikhail Barklon¹, Karl Edler¹, Lawrence Ryner¹, Denis Le Bihan²

Magnetic resonance has been performed at 123.2 MHz with an automated Cartesian feedback instrument immersed in ~ 2 T field. No change of electronic characteristics was observed upon field immersion. With a probe having a loaded Q-factor of 20, 40 dB current blocking with a 500 W RF power amplifier was obtained over a bandwidth of 20 kHz. A rectangular high power RF pulse exhibited no visible droop or phase change, while a ramp pulse exhibited no visible non-linearity or phase change. In signal reception over 160 kHz, current blocking of 40 dB was observed, a performance previously unattainable.