  The design of sensors or "things" as part of the new Internet of Underwater
Things (IoUTs) paradigm comes with multiple challenges including limited
battery capacity, not polluting the water body, and the ability to track
continuously phenomena with high temporal/spatial variability. We claim that
traditional digital sensors are incapable to meet these demands because of
their high power consumption, high complexity (cost), and the use of
non-biodegradable materials. To address the above challenges, we propose a
novel architecture consisting of a sensing substrate of dense analog
biodegradable sensors over which lies the traditional Wireless Sensor Network
(WSN). The substrate analog biodegradable sensors perform Shannon mapping (a
data-compression technique) using just a single Field Effect Transistor (FET)
without the need for power-hungry Analog-to-Digital Converters (ADCs) resulting
in much lower power consumption, complexity, and the ability to be powered
using only sustainable energy-harvesting techniques. A novel and efficient
decoding technique is also presented. Both encoding/decoding techniques have
been verified via Spice and MATLAB simulations accounting for underwater
acoustic channel variations.
