Installation and calibration of a parametric array for shallow water backscatter measurements

The calibration of the SIMRAD TOPAS PS040 parametric system as a transmitter is presented in the context of its application to seabed classification studies. Although the system can produce low frequency signals of various types (CW, chirp, Ricker) attention is restricted to the broad band, short time duration Ricker pulses. Meaningful seabed returns for the short pulse transmissions are only obtained if care is taken in the design of the installation of the system and the receiving hydrophones. The approach adopted is described.