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401027/B
Acoustic noise
As with any other hydroacoustic systems, the quality of the EM 712 echo data and
presentations are subject to unwanted acoustic noise. The echoes from any large and
small target must be detected inside the noise.
It is important that we keep the noise level as low as possible. The is necessary to obtain
long range and dependable interpretations of the echoes. Even with the advanced noise
filtering offered by the EM 712, we must address the noise challenge. This is important
during the planning and preparations for the EM 712 installation.
Topics
Electrical self noise, page 28
Some means to reduce acoustic noise, page 28
Contributing factors
Several factors are contributing to the performance of the hydroacoustic equipment
used on board a vessel.
Factors contributing to the performance of the hydroacoustic equipment used on board a
vessel are:
• The quality and properties of the transmitted signal
• The quality of the receiving system
• The operational settings made during operation
• The properties of the target(s)
• The signal-to-noise ratio
The majority of these factors can neither be controlled nor improved by means
of installation methods or transducer locations. The quality and properties of the
transmitting and receiving systems are key factors during our product development, while
our end user documentation aims to help the user to make the right filter settings during
operation. As for the target properties, there is nothing any of us can do with those.
The
signal-to-noise ratio
, however, can be improved by making the correct choices
during installation.
Signal-to-noise ratio (often abbreviated SNR or S/N) is a measure used in
science and engineering that compares the level of a desired signal to the level of
background noise. It is defined as the ratio of signal power to the noise power, often
expressed in decibels. A ratio higher than 1:1 (greater than 0 dB) indicates more
Kongsberg EM 712 Installation manual
Summary of Contents for EM 712
Page 71: ...401027 B 71 216148 EM 712 Transducer TX1 dimensions Drawing file ...
Page 72: ...72 401027 B Kongsberg EM 712 Installation manual ...
Page 73: ...401027 B 73 221048 EM 712 Transducer TX2 dimensions Drawing file ...
Page 74: ...74 401027 B Kongsberg EM 712 Installation manual ...
Page 75: ...401027 B 75 219621 EM 712 Transducer RX1 dimensions Drawing file ...
Page 76: ...76 401027 B Kongsberg EM 712 Installation manual ...
Page 77: ...401027 B 77 216146 EM 712 Transducer RX2 dimensions Drawing file ...
Page 78: ...78 401027 B Kongsberg EM 712 Installation manual ...
Page 79: ...401027 B 79 223137 EM 712 Transducer mounting frame 0 5 degrees Drawing file ...
Page 80: ...80 401027 B Kongsberg EM 712 Installation manual ...
Page 81: ...401027 B 81 223139 EM 712 Transducer mounting frame 1 degree Drawing file ...
Page 82: ...82 401027 B Kongsberg EM 712 Installation manual ...
Page 83: ...401027 B 83 223273 EM 712 Transducer mounting frame 2 degrees Drawing file ...
Page 84: ...84 401027 B Kongsberg EM 712 Installation manual ...
Page 85: ...401027 B 85 317812 EM 712 Casing w mounting frame 0 5 degrees Drawing file ...
Page 87: ...401027 B 87 375817 EM 712 Combined casing w mounting frame 1 degree Drawing file ...
Page 89: ...401027 B 89 396402 EM 712 Transmitter Unit dimensions Drawing file ...
Page 91: ...401027 B 91 396428 EM 712 Receiver Unit dimensions Drawing file ...
Page 92: ...92 401027 B 385422 Processing Unit dimensions Kongsberg EM 712 Installation manual ...
Page 93: ...401027 B 93 378828 Hydrographic Work Station dimensions Drawing file ...
Page 94: ...94 401027 B Kongsberg EM 712 Installation manual ...
Page 95: ...401027 B 95 371591 Rack installation kit dimenisons Drawing file ...
Page 96: ...96 401027 B 370275 Remote Control Unit K REM dimensions Kongsberg EM 712 Installation manual ...
Page 97: ...401027 B 97 Drawing file ...
Page 163: ...401027 B 163 Certificates IEC 60945 IACS E10 Technical specifications ...
Page 177: ...401027 B 177 7 Observe the handling rules for transducers Equipment handling ...
Page 188: ... 2018 Kongsberg Maritime ...