Simrad EK60 Scientific echo sounder

Simrad EK60

Using multiple frequencies

A typical Simrad EK60 installation onboard a research vessel will involve several operational frequencies. Maximum seven can be used, from 18 to 710 kHz.

Multiple frequencies are required to cover the broad scope of a marine acoustic survey. Such surveys range from studies of plankton to large fish schools from shallow coastal waters down to the deepest oceans.

Recent research has shown that simultaneous use of several discrete echo sounder frequencies not only improves fish stock estimates, it can also be used for species identification and discrimination. Each specie seems to have a unique acoustic frequency response (signature) due to frequency dependent acoustic backscattering. This new and growing understanding greatly improves the value of hydroacoustics to obtain information about marine resources.

Additional post-processing software applications may be provided from third party suppliers.

This Simrad EK60 screen capture shows the system operating with five frequencies simultaneously. The echogram shows a school of krill, and it is easy to see how this krill shows up differently for the different operational frequencies. The frequencies used are 18 kHz (top left), 38 kHz (bottom left), 70 kHz (top right), 120 kHz (middle right) and 200 kHz (bottom right).

Simrad EK60


Copyright Kongsberg Maritime AS 2007

Home