The Australian Antarctic Division has developed low power electronics to receive and record continuous, long term, acoustic data sets in the southern ocean. The device discussed includes custom electronics to implement signal conditioning, digital to analogue conversion and data storage.
The difficulty of accessing deployment sites in the Southern Ocean has led to the need for long term recordings, which has previously been solved through heavily duty-cycling recording systems. The design presented uses an array of commercial, flash RAM based, digital storage cards to provide an inexpensive, low power way of recording the large amounts of data necessary. Custom acquisition electronics allow further reduction in power consumption, minimising the mass and size of the batteries required to collect this data. Smaller, lighter batteries ease design requirements on enclosures and moorings.
The first deployment of the recorders occurred in 2012, and since then a total of 13 deployments have occurred with 8 successful recoveries, 1 lost at sea and 4 devices currently deployed. Future enhancements to the electronics will be discussed including a move to multiple channels, simpler architecture, and further reductions in size, cost and power consumption.