A three-dimensional flow velocity of underwater moving target and method and apparatus for determination of joint

The present invention discloses a three-dimensional underwater moving target speed and combined flow measurement method: Select the ground as the reference system for the ultrasound transmitter location coordinates of origin, under the horizontal plane perpendicular to the Z direction, to calculate the three-dimensional coordinates of the location of underwater objects ; Construction of single-frequency frequency fs of the velocity signal as the measurement signal and transmitted; ultrasound receiving module receives the N received signals received by the probe, and transfer them to the processing module, wherein the position of the i-th probe is received (xi, yi, zi), where i = 1,2,3 ...... N; N received signals are frequency estimate, the frequency of the received signal is obtained where i = 1,2,3 ... ... N, and calculate the flow rate and velocity of underwater objects using three-dimensional underwater target position, wherein n≥6. The method and apparatus of the present invention, it is possible to avoid adverse effects on the flow rate measurement accuracy, wide application range, good noise immunity, low cost, easy to install, easy to use.