Sound waves are
mechanical vibrations and travel easily through the ocean. Therefore,
compared to all other kinds of waveforms, they are the best suited
means to measure water depth or detect objects in the ocean.
The first device
designed to exploit underwater sound were echo sounders to measure
water depth, and they continue to play an important role in hydroacoustic
activities to this day. Acoustic ranging systems were created using
the echo-sounder principle, but applying it in the horizontal plane.
Since then, many
different applications have been dicovered and are presently in marine
use. New systems are continually being developed to exploit ocean
resources and improve military and commercial equimpment. These are
commonly referred to as SONAR systems.
This book is intended
to provide the design engineer with a work of reference. It is not
meant to replace the student's textbook, but rather to summarize the
state of art in sonar engineering. Therefore, phsysical principles
are explained only briefly, while emphasis is laid on tables, graphs
The field of underwater
engineering is presented in ten chapters, beginning with a brief presentation
of the fundamentals of vibration and acoustics which are prerequisites
for the later chapters on sound propagation and transducer operation.
A collection of case studies concludes this book