System description
The Simrad SU90 is a long range and low frequency fish finding sonar with a 360 degrees coverage. The SU90 system is designed for medium and large sized fishing vessels.It was originally developed for purse seiners, but experience has proven that it is also well suitable for trawlers.
If high performance is your number 1 criteria when choosing a sonar; such as long range, high resolution, narrow beams and high source levels, this is your natural choice. We made no compromises during the design of the SU90 system. Our goal was simply to make the ultimate high performance fish finding sonar.
The centre operational frequency is 26 kHz. You can select any operational frequency from 20 to 30 kHz. The cylindrical multi-element transducer allows the omnidirectional sonar beams to be tilted electronically. This allows you to automatically track schools of fish, and to observe the whole water volume around the vessel. A stabilizing system is included for electronic pitch and roll compensation. Compared to the Simrad SX90, the number of channels is increased by 50% giving the sonar an even better performance in selectivity and range.
The SU90 system offers a number of standard interface lines for communication with peripheral devices and sensors. Typical inputs are geographical information from a positioning system, vessel speed and current heading. By default, the SU90 system uses a built-in motion sensor. For improved operational accuracy, an external motion reference unit (MRU) can be connected.
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The narrow beam opening angle and the increased source level (3 dB) makes the SU90 a very powerful and high resolution low frequency sonar. The narrow beams provided by the SU90 system give you several advantages.
•  They increase the range and resolution, and offer a vertical view with additional details and a clearer picture.
•  They make the SU90 system even more ideal when you need to search for fish close to the sea bottom, or close to the surface, at long ranges.
•  They provide a far better vertical view with less "bottom climbing" that what is seen on sonars with a wider beam.
•  The narrow beams also decrease the noise level.
The SU90 system offers the same user interface and operating software as our other sonars, echo sounders and catch monitoring systems. This enables easier and faster training of new users.
•  The echo presentations are optimised for multiple displays. Provided that you have connected additional displays to your Processor Unit, you can use the Docking Views function to take any sonar view and place it on a separate display. When you move a view to another display, it will automatically be scaled for the best possible result.
•  It is common for sonars to require many pings to build the various views in the echo presentation. On the SU90, all the sonar views in the presentation are built using the echoes from one single ping. This dramatically improves the update rate and provides better real-time information.
•  The SU90 system permits you to record real-time sonar situations. This allows you to replay complete sequences. The playback contains the exact same echo information, and can be used for mission history, training or troubleshooting purposes.
Great emphasis has been placed on an intuitive user interface and the best possible sonar presentations on a high resolution colour display.
The SU90 system is equipped with the celebrated signal processing software developed by Kongsberg Discovery. This includes Hyperbolic FM (HFM) transmissions. This pulse type is also known as "chirp". It ensures a clutter free picture with very high resolution in range. The signal processing and beamforming is performed in a fast digital signal processing system using the full dynamic range of the signals.
The SU90 system software operates using the Microsoft® Windows® operating system.