Active and passive underwater acoustic applications using an unmanned surface vehicle

Unmanned Surface Vehicle (USV) is a novel kind of oceanic platforms, which is potential to be an effective platform for acoustic applications. Active and passive underwater acoustic experiments using our USV called USBV at Ji-hong-tan reservoir in Qingdao on July 15-17, 2015 and at Wu-zhi-zhou Island in the South China Sea on January 3-6, 2016 are presented to quantify this potential. The acoustic sensors integrated in USBV contain an acoustic modem, a self-contained hydrophone and a single beam echo sounder with CORS GPS. In active acoustic experiment, fixed and mobile acoustic communications, bathymetry and acoustic remote are evaluated using USBV. The favorable signal strength of communication ensures that USBV integrated an acoustic modem can be used as acoustic nodes, gateways and even mobile relay. The bathymetric survey is applied successfully for USBV using CORS-GPS without tides observation. In passive acoustic experiment, USBV's radiated self-noise in different situations and above communication's signal are recorded, so the acoustic signature of USBV is acquired. The low level of USBV's radiated self-noise affirms that USBV is a reasonable platform for passive monitoring. The above experiment results indicate that the USV integrated acoustic modem, echo sounder and hydrophone can benefit to active and passive underwater acoustic research.

I. Introduction

Due to improvement of underwater acoustic transducer and hydrophone as well as electronic technology, acoustic applications for oceanology emerge more and more commonly, such as bathymetry, communication, signal record, data collection, environment noise monitoring and wireless sensor network, and so on. In recent years, unmanned vehicle for oceanography are gradually mature and versatile, such as AUV and Glider, which have been already used in some underwater acoustic projects. Especially, Unmanned Surface Vehicle (USV) is a novel kind of oceanic platforms, which is potential to be an effective platform for acoustic applications.