Hydroid adds HISAS 2040 synthetic aperture sonar to boost REMUS 600 capability

Hydroid has integrated the Kongsberg High-resolution Interferometric Synthetic Aperture Sonar (HISAS) 2040 system onto a REMUS 600 unmanned underwater vehicle (UUV), Hydroid announced in early December.

The addition of the HISAS 2040 module, when combined with an associated in-mission processing capability, provides up to 2 cm by 2 cm underwater surveillance resolution “across a 300 m swath”, the company said in a statement.

A Hydroid REMUS 600 unmanned underwater vehicle is pictured fitted with an HISAS 2040 synthetic aperture sonar. (Hydroid)

“Synthetic aperture sonar uses algorithms to synthetically lengthen the aperture, providing consistent resolution across the entire swath, both along and across track, as opposed to traditional real aperture side-scan sonars,” said Hydroid.

The 300 m swath “is the maximum width of the sonar image that can be delivered at 2 cm by 2 cm resolution”, Sandor Becz, Hydroid’s Vice President of Engineering, told Jane’s on 11 December. “There are two transducers, one on each side of the UUV, [with] the EM2040 multibeam sonar that acts as a gap filler.”

The EM2040 fills what is known as the ‘nadir gap’ that occurs between two outward-looking sonars, Becz explained. “The sonar software stitches together data from these [sensors,] which results in the total swath of 300 m,” he added.

“With synthetic aperture sonar you get consistent resolution across the entire swath. This is a benefit over real aperture sonar, where the data resolution will degrade with range as you move to the outer edge of the swath.”