Assessment of Linearity of Bone-Conducted Ultrasound Transmission in the Human Head

We investigated the linearity of bone-conducted ultrasound transmission through a living human head. The frequency response functions and the coherence functions of head vibration at different signal levels were examined. Vibrations in the heads of six subjects were measured using a small accelerometer in the ear canal under bone-conducted tone stimulation from audible high frequencies to ultrasonic frequencies. Stepped sine signals from 10 to...