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UNDERSTANDING WIRELESS UNDERWATER COMMUNICATIONS
FACTORS THAT AFFECT WIRELESS COMMUNICATIONS
There are many factors that affect the propagation of sound in water.
The net result is that communication in water can be affected by local
conditions and the kind and depth of dive being conducted. The following
sections explain some of the factors that can affect the operating range of
underwater communication:
DISTANCE
The sound intensity from a source varies inversely with the distance
from the source. As the sound passes through the water, some of the
energy is converted to heat and some energy is scattered by fish, pilings,
seaweed, bubbles, etc. In addition, both the surface and bottom may
affect the sound intensity by either reflecting or diffusing sound waves.
If the source is near the surface, there is a point beyond which sound is
not received from the source. This point is said to be in a “Shadow Zone”.
The distance from the source to the shadow zone is determined by
Thermoclines in the water.
