We propose a new type of fiber hydrophone composed an etched Bragg grating and special packaging structure for detecting acoustic waves in the low-frequency band under water. The operating mechanism is based on mechanical vibration from induced vibrating stress pressure. pressure pushes silicone rubber thin film, causing its then stretching grating, thus resulting wavelength shift which overlap...

Click data from a tagged Mesoplodon densirostris was compared with broadband acoustic recordings from an 82 hydrophone wide-baseline array located in the Tongue of the Ocean, Bahamas. Two detectors, an Fast Fourier Transform (FFT) based detector and matched filter, were evaluated in white noise and with the acoustic recordings from the array for performance detecting M. densirostris clicks. The...

In this brief we present a design of full-duplex (FD) underwater acoustic communication (UAC) receiver with two-sensor transducer. The transducer consists two piezo-ceramic cylinders cast together in polyurethane resin; one acts as hydrophone and the other projector. As distance between projector is extremely short, high level self-interference (SI) from received at hydrophone. This SI must be ...

An approach of broadband mode separation in shallow water is proposed using phase speed extracted from one hydrophone and solved with sparse Bayesian learning (SBL). The approximate modal dispersion relation, connecting the horizontal wavenumbers (phase velocities) for multiple frequencies, used to build dictionary matrix SBL. Given a multi-frequency pressure vector on hydrophone, SBL estimates...

In this paper, environmental parameter estimation for a shallow ocean is addressed by using wideband shipping noise as a source of acoustic energy. Unknown locations of the broadband acoustic sources are estimated simultaneously with the ocean depth using the approximate Conditional Maximum Likelihood Estimator (CMLE). This procedure is tested via computer simulations and applied to the experim...

There is increasing concern about the potential effects of noise pollution on marine life in the world's oceans. For marine mammals, anthropogenic sounds may cause behavioral disruption, and this can be quantified using a risk function that relates sound exposure to a measured behavioral response. Beaked whales are a taxon of deep diving whales that may be particularly susceptible to naval sona...