A multifrequency acoustic probing system with the time signal division

A system for acoustic probing of seawater at four frequencies of signals radiated in series is described. The series-radiation circuit allows one to use one radiation section, one communication line with a bottom antenna, and simplifies the scattering- and reflection-signal filtering system. The received signals are inputted into and digitized in one channel, thus saving on the computer storage budget and decreasing requirements for speed of operation of the analog-to-digital converter. In principle, the number of serial frequency channels is limited by the time scales of observed processes and their dynamics.