Two-dimensional velocity distribution measurement by ultrasonic two-receiver interferometry

A method for measuring 2-D velocity distribution using three nondirectional transducers is proposed. In this method, the three transducers arranged in a line are used where the center one is a transmitter and the others are receivers. The echo signal from a moving target is received by the two receivers. The received signals are added and interfered with each other. When the ultrasonic pulses are transmitted repeatedly, the amplitude of the added signals fluctuates because of the movement of the target. The velocity of the target can be obtained by measuring the fluctuation frequency. The position of the target is provided by the time of flight of the transmitted pulse. As a result of the fundamental experiment, the possibility of this method to measure the 2-D distribution of the target velocity is confirmed