water motion; sediment transport; field equipment; laboratory equipment

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Acoustic Doppler Current Profiler (ADCP)

Instruments that use the acoustic Doppler principle transmit a short pulse of sound of constant frequency into the water, "listen" to its echo, and measure the variation in frequency of the echo with respect to the initial pulse. In this case, and according to the Doppler effect, this difference in frequency is proportional to the velocity of the water.