Kongsberg Simrad CP200-5C, Installation Manual

Page: 47 / 110

484164/A
45
Acoustic noise
Topics
Contributing factors, page 45
Self noise, page 47
Ambient noise, page 49
Fishing gear noise, page 50
Electrical self noise, page 50
Some means to reduce acoustic noise, page 51
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 you 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 signal than noise. While SNR
is commonly quoted for electrical signals, it can be applied to any form of signal [...].
Preparations