A Deep-Ocean Acoustic Position Keeper.

摘要

An acoustic transponder has been developed for use at sea to enable oceanographic ships to maintain a given position in an area where navigational control is poor. The system is comprised of a buoyant subsurface float containing the battery-operated transistorized electronics, .040-in. piano wire, and a simple anchor weight. The operating depth of the subsurface float is adjusted between 2000 and 4000 ft by the length of the piano wire. The operation of this acoustic position keeper (APK) is as follows: The outgoing pulse from a fathometer is picked up by a hydrophone mounted on the float and processed by a narrow-band amplifier which keys a power oscillator, tuned to the fathometer frequency, driving a specially built ceramic transducer. Thus, for each outgoing fathometer ping, two echoes are recorded on the echogram: (1) a ping from the float and (2) the prolonged bottom reverberation. The slant range to the APK is read from the echogram, and the horizontal range is obtainable if the depth of the APK is known.