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Sound Metrics provides a few types of non-rotating multibeam sonars, the ARIS Explorer 3000 and Didson sonars primarily. The ARIS Explorer operates at a frequency of 3 MHz with 128 beams, while the Didson sonar is similar, operating at a lower centre frequency. Both sonars cover 28 degrees horizontally and 14 degrees vertically. For more information, see the manufacturer's website: http://www.soundmetrics.com. The ARIS software ARIScope and Didson software can be requested through the Sound Metrics website http://www.soundmetrics.com (go to the support page) or contact us. The main data product for these sonar are documented here: Sound Metrics sonar data
This data product is an annotation (.an) file containing a record of potential movement detections in the Sound Metrics sonar data as generated by the data product post-processor only. As such as, these files may not yet be generated and made available for all ARIS and DDF files; Data Search will return only the files that are in the archive (Unlike Sound Metrics sonar data files that may be generated on-the-fly from ARIS and DDF files). Movement detections by the post-processor also trigger an email to be sent out to subscribers with the same information as stored in this file. (Contact us if you would like your email address to be added post-processor's recipient list, internal documentation link: Sound Metrics Sonar MATLAB Post Process Job.). The algorithm is simple and described in the email (see below). The parameters have been tuned for the initial data and maybe updated with new deployments, devices, etc. The parameters are device and time specific and are set by the device attributes system. The algorithm does generate false-positive detections in cases of poor quality images (such as a bad focus), although it is mitigated in normal operation.
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