Passive electrical isolation of double coil probes for localized spectroscopy and imaging

A circuit is described for the electrical isolation of double coil probes where separate transmitter and receiver coils are both tuned to the same frequency and are coupled by mutual inductance. There are only passive components in the probe, and so no additional control signals are required for switching between transmit and receive conditions. An analysis of the operation of the circuit is included together with details of component selection and setting-up procedures, thus facilitating the implementation of the design for a variety of applications in both imaging and spectroscopy.