Acoustic Doppler Current Profilers (ADCP)
Nortek makes two different model series of current profilers. Each model series is targeted for specific, stationary applications.
The Continental is the "big brother" of the series. It is intended for use at water depth down to 500 m and it can profiler over ranges of 100-300 m.

The Aquadopp profiler is a small and lightweight profiler for use in the coastal ocean. It has a standard and a special firmware, which is referred to as HR. In HR mode, the instrument is capable of measuring rapidly and with high resolution over a short range.
The VMCP is mounted on ships and more details about this product can be found here
Current profilers operate by sending out short acoustic pulses from two or more acoustic beams.

