A new long range current profiler

When designing ADCPs, we trade off profiling range, vertical resolution and energy consumption. The last point is restricted by the availability of batteries and is usually fixed for a planned deployment. The first two points are intertwined in a complex relation because good vertical resolution requires both short acoustic pulses and a reasonably wide bandwidth, both of which lead to shorter range. As such, it is hard to reach any breakthrough in the range-resolution characteristics of an ADCP without finding a completely new approach to estimating velocity from the acoustic echo. Against this backdrop, our development of a new long range current profiler focused on optimizing each element in the system that we could control, from transducer design to mechanical design, from power consumption to profiling range, and from interfacing to data storage. Combined with a very flexible timing controller, this novel system provides the basis for a new generation of current profilers where the hardware platform is referred to as AD2CP, of which the Signature75 long range current profiler is the first fully commercial implementation. In a recent test outside Toulon France, the system functioned every bit as efficiently as we could have hoped and collected velocity data over a profiling range exceeding 900 meters in the Mediterranean.