Development of a prototype for submarine communications in shallow waters

The Telecommunications Marine Laboratory (TML) of the University of
Cádiz takes part in a research project to study the intertidal sediments of the Bay
of Cádiz. The collection of samples from the seabed and the transmission of data
to the surface are performed by a Mini Profiler with four channels (MP4), which is
supplied by UNISENSE. Each channel processes the samples collected by a single
sensor. For power, control, and data transmission, a special wiring that connects the
submerged subsystem with the surface subsystem is used. The tension transmitted
by the cable to the MP4 structure makes its handling and positioning under water
more difficult. This article explains the technological solution developed by the TML
to replace some wiring from the MP4. For the prototype, two underwater acoustic
modems have been used and an electronic system has been developed based on the
Arduino platform, in order to multiplex, digitize, and transmit the data collected by
the MP4 sensors, eliminating the need to use wiring. The submerged subsystem has
an autonomous power supply by a battery.