Parametric Acoustic Array and Its Application in Underwater Acoustic Engineering

Array Processing: Underwater Acoustic Source Localization

Evaluation of underwater acoustic propagation model (Ray theory) in a river using Fluvial Acoustic Tomography System

Underwater acoustics is widely used in many applications, such as oceanography, marine biology, hydrography, fishery, etc. Different models are introduced to simulate the underwater acoustic propagation in the oceans and the seas. In this study, the Ray Theory model is used to simulate the acoustic wave propagation in a shallow-freshwater river (Gono River) located in western part of Japan. The...

Covert underwater acoustic communications.

Low probability of detection (LPD) communications are conducted at a low received signal-to-noise ratio (SNR) to deter eavesdroppers to sense the presence of the transmitted signal. Successful detection at intended receiver heavily relies on the processing gain achieved by employing the direct-sequence spread-spectrum (DSSS) technique. For scenarios that lack a sufficiently low SNR to maintain ...

Underwater Acoustic Networks

With the advances in acoustic modem technology that enabled high-rate reliable communications, current research focuses on communication between various remote instruments with in a network environment. Underwater acoustic (UWA) are generally formed by acoustically connected ocean-bottom sensors, autonomous under water vehicles, and a surface station which provides a link to on-shore control ce...

Adaptive Underwater Acoustic Communications

Underwater wireless networks consist of mobile and static nodes, which usually communicate using the acoustic channel since radio transmissions attenuate rapidly and optical communication is only suitable for short distances. The underwater acoustic channel is plagued with issues of high transmission power requirements, rapidly changing channel characteristics, multi-path echoes, possible high ...