If you were tasked with finding and tracking a 25-meter long object, you could probably apply your Electrical Engineering skills to devise a range of different methods. Whilst these methods might work on land, applying them to an aquatic environment causes problems. Conventional techniques - involving the transmission of (RF-)signals - are quickly eliminated by the attenuating properties of water (at roughly 9dB/mm [1]). This is a major problem for marine biologists who seek to track marine animals and their migration movements. ...