A NETWORK ANALYZER-BASED TISSUE CHARACTERIZATION SYSTEM

A novel ultrasound tissue characterization system is described which u tilizes a network analyzer, S-parameter test set, 180 degrees hybrid j unction, and a mock transducer circuit to exploit the wide-band potent ial of a commercial piezoelectric polymer transducer. The relatively s hort round-trip pulselength achieved using the system (70 ns in water) is compared to that obtained using a high-frequency pulser/receiver a nd the same transducer (130 ns in water). Finally, the in vitro acoust ic response of a section of neonate porcine carotid artery obtained us ing the network analyzer-based system is reported, along with histolog ic results for the same vessel.