Duplexer including a field-effect transistor for use in an ultrasound imaging system

摘要

A duplexer for an ultrasound imaging system is capable of selectively coupling a transducer element to either a transmitter or a receiver, depending on whether the imaging system is in the transmit mode or receive mode. The duplexer contains a field-effect transistor whose source and drain are connected between the transducer element and the receiver. The gate of the field effect transistor may either be driven with a control voltage or short-circuited to the source. In this manner, one obtains an improved duplexer that operates with virtually no power loss, without drive circuits, without leakage currents, and with low noise.