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Cylindrical shell transducers are widely used in underwater acoustic engineering. For example, free-flooded ring transducers are often used as transmitters in underwater acoustic communication devices. However, there are few papers about the transient sound field generated by cylindrical shell transducers in a shallow ocean. In this study, the problem of the transient sound generated by a cylindrical...
The purpose of this paper is to introduce a new beamforming method for sonar imaging, which is proposed based on the plane wave decomposition combine with back-propagation method and with transverse oscillations. This method was initially proposed for ultrasound Doppler imaging using transverse oscillations in linear geometry. The plane wave decomposition theory is used to decompose in different directions...
Conductivity, temperature and depth (CTD) are the most essential physical properties of sea water. CTD instrument is one of the most efficient approaches for collecting the accurate ocean information. However, traditional CTD instruments are not best suited for applications that require high resolution data by a large number of sensors because of their large size and high cost. This paper describes...
The sonar system of JiaoLong human occupied vehicle(HOV) consists of nine kinds, sixteen sonars for communication, navigation, positioning, and detection. There is a ultra-short baseline(USBL) and a long baseline(LBL) for positioning. USBL is used to localize JiaoLong. Through it, the mothership can get HOV position in real-time. By Acoustic Communication System, HOV can get its own position every...
Recently, underwater acoustic communication system has been received a great interest due to its wide application areas. Since acoustic modem is one of the core technologies for underwater communication systems, there have been many efforts to improve the performance of acoustic modem in terms of data rate, working range, power consumption, size and cost by utilizing state-of-the-art physical layer...
Acoustic systems are used widely to provide quantitative estimates of biomass for fisheries and ecosystem assessments. Traditionally, these systems are attached to surface vessels, but increasingly they are being fitted to remote operated vehicles, autonomous vehicles and towed platforms. These platforms allow the acoustic transducer to get closer to targets, and provide increased resolution and,...
High-resolution bathymetric sidescan sonar system (HRBSSS) is a kind of acoustic detection equipment for the micro-topography of the seafloor. This paper briefly introduces the working principle, the main error sources, the data processing and error calibration method of HRBSSS at first. On this basis, a sounding data quality assessment method including one part for the sonar and the other for the...
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