Abstract— This work investigates wh

Abstract— This work investigates whether a contactless,
wireless underwater coupling could be developed for underwater
sensor networks. This requires the wireless transmission of power
from the sensor hub to the transducer module, and the two-way
wireless data communication between hub and transducer.
Results from a trial deployment of systems with conventional
waterproof couplings show that these are a major shortcoming of
existing systems. Experiments are conducted which demonstrate
that a Zigbee transceiver, operating in the 2.4GHz band, can
communicate with low error rates up to 40mm at low RF power
25dBm) and up to 70mm at higher power (-3 dBm) in seawater.
Ranges are slightly higher in fresh water. Inductive power
transfer, using a split transformer design, can transmit low
power, in the 50-100mW range with efficiency of approximately
50%, demonstrating that wireless sensor couplings are feasible.