Impulse response estimation method for ultrasound arrays

Abstract

We present a method for estimating the one-way electro-mechanical impulse response or transfer function of self-reciprocal ultrasound transducers. The one-way impulse response is needed for forward field simulations, or for pulseecho simulations and excitation code design when the oneway impulse response per array element is different. Using a flat plate reflector that is positioned parallel to the transducer surface, the resulting pulse-echo signal is measured. Since the transducer is self-reciprocal, the transmit and receive impulse responses are equivalent. Consequently, the measured signal is the autoconvolution of the one-way impulse response. We propose a new de-autoconvolution algorithm to obtain the one-way impulse response from such a signal. The proposed measurement procedure is especially time-efficient for large arrays, and does not rely on hydrophones or additional transducers. Experimental results are shown to demonstrate the effectiveness of the proposed method.