The DTAG-3 was designed in 2010-12 at the Woods Hole Oceanographic Institution by Johnson, Hurst and Shorter as a complete revision of the DTAG-2. Objectives were to (i) halve the volume of the tag so as to make it suitable for small odontocetes, and (ii) increase the recording time and/or bandwidth of the tag. Interfaces for new sensors were also included along with a more powerful processor, increased memory capacity and a full speed USB interface. To meet the size goal, an integrated design approach was adopted leading to a compact fully-cast design. The electronic cavity in the forward section of the tag is either oil-filled or cast in epoxy. The rear section houses the syntactic foam floatation and the entire tag is over-potted in polyurethane. The tag still has four suction cups but these are now x mm diameter each and mount directly on the tag body. The 220 MHz VHF beacon is now powered from the same rechargable battery as the tag electronics to save weight and a watch-dog microprocessor manages the battery to ensure that sufficient charge is kept for tag recovery.
The DTAG-3 has 32-64 GB of memory and has a recording time of up to 3 days depending on sampling rate. Several versions of the DTAG-3 have been built with different sensor suites. These include high-frequency stereo tags with 160 kHz recording bandwidth for porpoises, as well as tags with gyroscopes, GPS and ECG sensors. A DTAG-3 with a 1.5 MHz echosounder is currently being tested. A new long-duration version of the DTAG-3 for use on seals is also being designed. This will include an Argos transmitter and a Lithium primary cell giving up to 1 month of continuous recording time. An early version of this device is currently being used as a passive acoustic monitor on ocean gliders.
Software and drivers for the DTAG-3 can be downloaded here.
The latest (but still beta-testing) drivers are here:
This document describes how to install the D3 USB device drivers on your computer and how to get started collecting data:
This document describes the XML format used by D3 devices to store metadata collected throughout deployments:
The D3 matlab tools are here:
These include functions for extracting information from the XML records and for accessing data from the sensor and audio files generated by D3 devices. To use these tools you should also download the general tag tools:
When you unzip these files, add the directories that they generate to your matlab path using File->Save Path->Add with Subfolders.
You will also need XML tool box (by Almeida et al.) which you can download here: XML.MAT.zip