Low-power ultrasound imaging systems using time delay spectrometry

Ultrasound (US) imaging systems have undergone substantial miniaturization recently and have given rise to many potential applications where battery-based operation is desirable. However, current clinical US systems utilizing pulse-echo imaging require high voltage and short duration transmit pulses along with electronics that operate in the MHz frequency range. As an alternative, we have developed an imaging method that employs time-delay spectrometry (TDS), and uses low-voltage (∼5V peak-to-peak) transmit pulses to allow operation at significantly lower acoustical output power levels making it suitable for long-term monitoring applications. Using this technique, we generated M-mode images in real time with 5 cm of depth and a pulse repetition frequency of 50 Hz. TDS produced improved contrast compared to conventional pulseecho US systems at low MI and TI. TDS could lead to a new generation of low-power US imaging systems.