TEM Cell for Calibration of an Electro-Optic E-Field Sensor in a Clinical Scanner

Frank Seifert¹, Tobias Klepsch¹, Tomasz David Lindel¹, Werner Hoffmann¹, Bernd Ittermann¹

EM field simulations of RF coils and coil arrays are basic tools for predicting SAR in the human body. Besides B1(+) measurements, complementary E-field measurements using MR compatible E-field sensors are inevitable for an experimental validation of such simulations using the MR scanner itself. However, the significance of such measurements is limited by the quality of the sensors calibration. We present a MR compatible transverse electromagnetic cell (TEM cell) used as calibrating device for a time-domain electro-optic E-field sensor via B1(+) measurements. Since in a TEM cell the E-Field is exactly related to the B1(+) field by E = 376.73 Ohm*2*B1(+)/0 the calibration procedure is based on MR techniques only.