A solution to velocity ambiguity of broad-band acoustic Doppler current profiler

Broad-band acoustic Doppler current profiler (BBADCP) adopts repeated phase-coded signal and complex auto-correlation technology to estimate current velocity. It has high precision but accompanies velocity ambiguity. In this paper, a method used to solve velocity ambiguity is proposed. Every transducer transmits two pulse pairs with different code length to get two measured velocities using complex autocorrelation method. The measured velocities are combined with the repeated phase to get two sets of possible velocities. And finally accurate velocity can be obtained by comparing the velocities in the two sets. The simulations demonstrate the effectiveness of this method.