A Practical Parametric Magneto-Inductive Ring Detector
نویسندگان
چکیده
A parametrically amplified ring detector for magnetic resonance imaging (MRI) is presented. The system consists of eight coupled PCBs arranged as an octagon. Each carries three L-C resonators, for signal, idler and pump frequencies. Adjacent signal resonators and pump resonators are magnetically coupled, so these two frequencies propagate as magneto-inductive waves; however, the idlers are uncoupled. The signals interact via varactors, allowing amplification of signals from a rotating dipole source by the threefrequency process. Uniform gain is demonstrated in a non-magnetic system suitable for H MRI at 1.5T.
منابع مشابه
Three-frequency parametric amplification in magneto-inductive ring resonators
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