Fig. 1.
Spectra of HFO and HNA hydrophone measurements from three transducers. Transducer center frequencies are given in the upper right corner of each plot. Spectra are deconvolved for hydrophone frequency-dependent sensitivities and normalized to their values at their fundamental frequencies. HNA data decrease with frequency more rapidly than HFO data due to greater spatial averaging effects resulting from the larger nominal geometrical sensitive element diameter (400 μm vs. 100 μm).
