Introduction

A Multibeam Echo Sounder is a complete survey system made up of several sensors working together. The Multibeam Echo Sounder, GNSS receiver, motion sensor, heading sensor, sound velocity sensor, and survey software must all be connected and configured correctly.

A proper setup helps reduce survey errors and improves the quality of the final bathymetric map.

Equipment Required

Before starting the survey, make sure you have the following equipment:

• Multibeam Echo Sounder
• Transducer Array
• GNSS Receiver
• GNSS Antenna
• Motion Sensor (MRU or INS)
• Heading Sensor
• Sound Velocity Sensor
• Sound Velocity Profiler (SVP)
• Survey Computer
• Hydrographic Survey Software
• Power Supply
• Survey Vessel or USV

Step 1 – Prepare the Survey Vessel

Check that the survey vessel is ready for operation.

Inspect all equipment, cables, connectors, and mounting brackets.

Make sure the batteries, generator, or onboard power system are working correctly.

Step 2 – Install the Multibeam Transducer

Mount the Multibeam Echo Sounder transducer securely on the vessel hull or a dedicated mounting pole.

The transducer should remain fully underwater during the survey.

Ensure there are no objects that can block or disturb the sonar beams.

Step 3 – Install the GNSS Antenna

Install the GNSS antenna on the highest practical point of the survey vessel.

The antenna should have a clear view of the sky for reliable satellite reception.

Measure and record the antenna position relative to the transducer.

Step 4 – Install the Motion and Heading Sensors

Mount the Motion Sensor (MRU or INS) close to the vessel’s center where movement is most stable.

Install the Heading Sensor according to the manufacturer’s instructions.

These sensors measure the vessel’s roll, pitch, heave, and heading, allowing the software to correct the survey data.

Step 5 – Install the Sound Velocity Sensor

Install the Sound Velocity Sensor near the transducer so it can measure the speed of sound at the water surface.

Before the survey begins, use a Sound Velocity Profiler (SVP) to collect sound velocity data through the water column.

This information helps improve the accuracy of depth measurements.

Step 6 – Connect All Equipment

Connect the Multibeam Echo Sounder, GNSS receiver, Motion Sensor, Heading Sensor, Sound Velocity Sensor, and survey computer.

Check every cable and communication port.

Confirm that all devices are communicating correctly before starting the survey.

Step 7 – Configure the Survey Software

Open the hydrographic survey software and create a new project.

Enter the correct coordinate system, vessel offsets, sensor offsets, draft value, and sound velocity information.

Check that all sensors are displayed correctly in the software.

Step 8 – Perform System Checks

Before collecting data, verify that every sensor is providing stable information.

Check the GNSS position, vessel heading, motion data, sound velocity, and Multibeam swath display.

If any sensor shows abnormal readings, solve the problem before continuing.

Step 9 – Run a Patch Test

A Patch Test is performed to check and correct the alignment between the Multibeam Echo Sounder and the vessel sensors.

This process improves the accuracy of the final bathymetric data and is an important step before starting a detailed hydrographic survey.

Step 10 – Start the Survey

Navigate the survey vessel along the planned survey lines at a steady speed.

Monitor the swath coverage, depth values, sensor status, and data quality throughout the survey.

Continue recording data until the entire survey area has been covered.

Common Mistakes to Avoid

Incorrect sensor offsets, poor GNSS reception, loose transducer mounts, missing sound velocity measurements, and unstable vessel speed can reduce survey accuracy.

Always check the complete system before collecting data.

Best Practices

Inspect all equipment before every survey.

Collect a new sound velocity profile whenever water conditions change.

Verify vessel offsets carefully.

Monitor sensor quality during the survey.

Back up survey data regularly.

Schedule regular equipment calibration and maintenance.

Conclusion

A properly configured Multibeam Echo Sounder system produces accurate and reliable seabed maps. Following the correct setup procedure helps surveyors reduce errors, improve data quality, and complete hydrographic surveys more efficiently.