Use of a nearfield array for acoustic backscattering cross‐section measurments Available to Purchase

It is theoretically demonstrated that a circular piston operating at high frequency can be used as a nearfield array to receive and measure farfield backscattering (sonar) cross sections. Experiments are described which use a 4.75‐in.‐diam piston operating at 15 MHz as a transmitter/receiver within the nearfield zones of the piston and scattering object. Results obtained are in good agreement with those theoretically predicted by finite‐beam insonification‐scattering theory. Comparison of scaled‐model ship measurements with farfield values shows reasonable agreement as well.

Subject Classification: [43]30.82; [43]30.40.