Depending upon the application, it can make sense to combine 2 or 3 multibeam instruments with different frequencies into one system. A higher frequency instrument will most often have better resolution and accuracy than a lower frequency instrument for a certain water depth. The different frequency models listed below are compatible and can be combined freely. If only one instrument is used at a time, a single operator unit is sufficient. However, when more than one frequency is activated for simultaneous operation, one operator unit is required for each instrument.

Single frequency models

Model Frequency Min/max depths*) Max swath width Comments
EM 3002 300 kHz 0.5-200 m 4xD/200 m -
EM 3002D 300 kHz 0.5-200 m 10xD/250 m 6
EM 2000-120 200 kHz 1-300 m 3.6xD/300 m -
EM 2000-150 200 kHz 1-300 m 7.5xD/300 m -
EM 710RD 70-100 kHz 3-600 m 5.5xD/800 m 1, 3, 7
EM 710S 70-100 kHz 3-1000 m 5.5xD/1900 m 1, 3, 8
EM 710 70-100 kHz 3/-2000 m 5.5xD/2500 m 1, 3, 9
EM 302 30 kHz 10-7000 m 5.5xD/10km 1, 2, 3, 4
EM 122 12 kHz 20-11000 m 5.5xD/35km 1, 3, 5

Note: EM 710 is new from 2005, EM 122 and 302 are new systems in 2006.

No. Comments
1 This system is available in several sizes of transducers/beamwidths: 0.5x1, 1x1, 1x2,
2x2, 2x4 (not EM 710) degrees
2 Also available as 4x4 degrees
3 Max swath width is for the largest transducer configuration and acoustically hard bottom
4 Can be integrated with SPB 302 sub bottom profiler
5 Can be integrated with SPB 120 sub bottom profiler
6 Uses 2 sonar heads
7 RD model uses only short CW pulse
8 S model uses only CW pulses
9 The full EM 710 uses CW and FM sweep pulses


Advantages of a multibeam echo sounders
We are a leading manufacturer of multibeam echo sounder systems for seabed mapping. Our product range includes models for all water depths, and virtually any application. The benefit of multibeam echo sounders is that they map the seafloor by a fan of narrow acoustic beams, thus providing 100% coverage of the bottom. The resulting seabed maps are more detailed those obtained using single-beam mapping. The maps are also produced faster, reducing your ship survey time.
High accuracy
Our multibeam echo sounders are professional tools for precision mapping of the seabed, complying with the performance standards defined by the International Hydrographic Organization’s performance standards, S-44 edition 4. Our instruments are all characterized by high mapping productivity in combination with exceptionally high sounding accuracy, and a dense pattern of soundings to cover the seafloor in order to reveal all details on the bottom. In addition to the soundings, the multibeam echo sounders produce seabed image data similar to a sidescan sonar image. This dataset is useful for characterizing the seabed material properties and sometimes for detecting small features not visible in the sounding data.
Complete mapping system
To form a complete mapping system, our multibeam echo sounders are connected to positioning equipment, heading and motion sensing instruments, as well as sound velocity sensors in order to position the soundings correctly.
Portable solutions
Portable solutions can be offered for inshore surveying. Permanent or semi-permanent mounting of the acoustic transducers is recommended for offshore work with surface vessels. Solutions for ROV- and AUV-based multibeam surveying are available. We have considerable experience and can assist you with practical advice.
Realtime software
Our multibeam echo sounders are operated from a graphic display workstation. Our realtime software includes extensive tools for visualizing the sounding data as well as the seabed image data, and to check the system calibration and the data quality. Preliminary maps can be produced and plotted almost immediately after a survey is finished.
Post-processing software
Post-processing software for cleaning and correcting of multibeam sounding data is offered, as well as tools for producing seabed image mosaics and classification of the seabed sediment types. We offer solutions for complete data processing all the way to the final products, including electronic chart data in the form of S-57 databases and plotting of paper charts.
Prepared for integration
Our multibeam echo sounders are prepared for integration with other acoustic instruments and can be used as subsystems in integrated survey instrumentation solutions, involving centralized synchronization of the transmission sequence and Marine Data Management.