Interphase PC/View, Operation Manual

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typically show only those targets that are within
this main beam width. A large beam width will
show targets from a larger underwater area, but
suffers from lack of resolution. That means that
although several targets may be in the beam
width, the user can only determine their distance
from the transducer, not their lateral position
within the beam. For example, if one fish target
is 10’ below the boat at the far right edge of the
beam angle, it will show the same display as if it
were 10’ below the boat at the far left edge of the
beam angle. In addition, if fish are present at
exactly the same depth but at different sides of the
underwater beam, the transducer will receive
echoes from both fish targets at the same time and
the display will only show a single target. This is
a serious limitation to the conventional
technology.
To get around this limitation, several
manufacturers have resorted to adding more
piezoceramic elements to the transducer, each
pointed in a different direction. By selectively
using each piezoceramic element the transducer
has the ability to point or look in as many
different directions as there are piezoceramic
elements. After approximately four elements,
however, the transducer housing starts to become
physically large and cumbersome. To date,
manufacturers have put as many as five separate
elements into the transducer to enable users a
view in up to five different underwater directions.
For the future, Interphase believes that this
multiple fixed-beam approach has serious
limitations, especially for use in more advan ced
products where maximum underwater coverage
and resolution are important.
Phased Array Technology
To get around these limitations and provide a
sonar system that can achieve both outstanding
coverage and good resolution, Interphase
pioneered the use of Ultrasonic Phased Array
Technology. In 1991, we received the prestigious
IMTEC Innovation Award in recognition of the
importance of this new technology to the marine
industry. Although new to the sportsfishing and
recreational marine industry, “phased array
Bottom
Three Fixed-Beam System, Looking Down and
to Each Side of Boat