Aravind Nagulu1, Ahmed Kord1, Gehua Tong1, Michael Garwood2, Lance DelaBarre2, Djaudat Idiyatullin2, SungMin Sohn3, J. Thomas Vaughan1, and Harish Krishnaswamy1
1Columbia University, New York, NY, United States, 2University of Minnesota, Minneapolis, MN, United States, 3Arizona State Univeristy, Tempe, AZ, United States
1Columbia University, New York, NY, United States, 2University of Minnesota, Minneapolis, MN, United States, 3Arizona State Univeristy, Tempe, AZ, United States
Our circulator which is designed to
operate with a 1.5 Tesla eight-channel TEM head coil and achieves a transmission
loss of 6.1dB and 5.8dB in the TX and the RX paths respectively, while
achieving a TX-to-RX isolation of 75dB at 64MHz.
Figure 1: Concept diagram of the (a)
switched transmission line gyrator and (b) 3-port circulator.
Figure 5: Measured TX-to-RX leakage when the circulator is
terminated with 3 of the 8 channels of a 1.5 T MR coil. The dotted red line depicts
the isolation presented by the circulator when the MR coil is loaded with a
human head.