Rodrigo Pereira Barretto da Costa-Félix, S. Miqueleti, Carlos Eduardo Parente Ribeiro, Carlos Alfredo Orfao Martins
{"title":"Reciprocity calibration of hydroacustic transducers using swept-sines (chirps)","authors":"Rodrigo Pereira Barretto da Costa-Félix, S. Miqueleti, Carlos Eduardo Parente Ribeiro, Carlos Alfredo Orfao Martins","doi":"10.1109/RIOAcoustics.2013.6684007","DOIUrl":"https://doi.org/10.1109/RIOAcoustics.2013.6684007","url":null,"abstract":"The three hydroacoustic transducers reciprocity principle is the base for a widely used and well known technique for sensitivity calibration in the frequency range between 1 kHz and 1 MHz. For practical reasons, at least one, and not necessarily all, of the transducers should be reciprocal to comply with the method requirements. In a typical setup, in which the excitation signal are discrete frequency tone bursts, free and far fields are mandatory; otherwise signal interferences, such as reflections on surfaces and diffractions due finite aperture width, would preclude trustworthy results. However, an alternative approach, combining signal processing and the basic theory for reciprocity, minimizes the necessity of both free and far fields. Further, using this technique, calibration can be performed in a quasi-continuous and broad frequency range in a single shot, avoiding the time-consuming stepped-sine excitation signal. The approach is based on the use of a non-conventional chirp-signal (or swept-sine) used as excitation, which is developed under a frequency spectrum magnitude prescription. In this paper it will be presented the description, employment and comparison of the conventional calibration by reciprocity and non-conventional technique using chirps.","PeriodicalId":245877,"journal":{"name":"2013 IEEE/OES Acoustics in Underwater Geosciences Symposium","volume":"163 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132729704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"High productivity multi-sensor seabed mapping sonar for Marine Mineral Resources Exploration","authors":"M. Rioblanc","doi":"10.1109/UT.2013.6519881","DOIUrl":"https://doi.org/10.1109/UT.2013.6519881","url":null,"abstract":"Marine Mineral Resources Exploration is an emerging activity requiring suitable equipment that will deliver on a timely manner both geo-referenced seabed maps and sub-bottom profiles. The race for deep sea mining has globally started while costs involved have to be minimized at all stages from exploration to exploitation. Building on its 20-year long experience in designing and manufacturing active transducers and passive sensors, the Sonar Systems Division of iXBlue is also at the cutting edge of the synthetic aperture sonar (SAS) development while mastering the long range underwater acoustic communication transducer technology (used for instance by JAMSTEC) and the Wide-Band, Flat Spectrum Sub-Bottom Profiler Transducers. The SAMS is a modular Synthetic Aperture Mapping Sonar product-line delivering real-time geo-referenced maps at a high productivity rate (>133km2/day). Several solutions with diverse resolutions and ranges are available while host platforms are multiple (Towed Fish, AllV). The SAMS-DT6000 in particular will be presented as it has been especially designed for Marine Mineral Resource Exploration as deep as -6000m.","PeriodicalId":245877,"journal":{"name":"2013 IEEE/OES Acoustics in Underwater Geosciences Symposium","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126272424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Sousa-lima, D. P. Fernandes, T. Norris, J. Oswald
{"title":"A review and inventory of fixed autonomous recorders for passive acoustic monitoring of marine mammals: 2013 state-of-the-industry","authors":"R. Sousa-lima, D. P. Fernandes, T. Norris, J. Oswald","doi":"10.1578/AM.39.1.2013.23","DOIUrl":"https://doi.org/10.1578/AM.39.1.2013.23","url":null,"abstract":"Fixed autonomous acoustic recording devices(autonomous recorders [ARs]) are defined as any electronic recording system that acquires and stores acoustic data internally (i.e., without a cable or radio link to transmit data to a receiving station), is deployed semi-permanently underwater (via a mooring, buoy, or attached to the sea floor), and must be retrieved to access the data. More than 40 ARs were reviewed. They varied greatly in capabilities and costs, from small, hand-deployable units for detecting dolphin and porpoise clicks in shallow water to larger units that can be deployed in deep water and can record at high-frequency bandwidths for over a year. The capabilities and limitations of the systems reviewed herein are discussed in terms of their effectiveness in monitoring and studying marine mammals.","PeriodicalId":245877,"journal":{"name":"2013 IEEE/OES Acoustics in Underwater Geosciences Symposium","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125602708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}