EMFi based ultrasound transceivers

The paper presents some transceivers for ultrasonic transducers based on Emfit Ferro-Electret Film (EMFi). The proposed and discussed transceivers use the wide bandwidth of EMFi material-from audio up to hundreds of kHz, for in-air biomimetic sonar applications, allowing thus to develop new algorithms for object detection, recognition and navigation based on frequency modulation algorithms. Technological process of building new ultrasonic transducers, starting from blank EMFi foil, is presented as well as electronic circuits used for transmitter and receiver. Three transmitter circuits were designed and presented, all of them being capable to drive a capacitive load of about 30pF with 300Vpp sinusoidal signal, up to 300 kHz.