Voices from the deep - Acoustic communication with a submarine at the bottom of the Mariana Trench

In March 2012 the first solo submarine dive to the bottom of the Mariana Trench was successfully completed by movie director and explorer, James Cameron. An Australian built submarine was piloted untethered 10.9 km downwards to the deepest ocean point on earth, whilst maintaining reliable voice and data communications to two surface vessels throughout the journey. This paper gives an account of the dive, and describes how the communications equipment was made to perform reliably in these unique circumstances.