Acoustics Research Group

Synthetic aperture sonar (SAS) is used for creating high-resolution acoustic images of the sea-floor. A high-end SAS is capable of imaging a golf-ball at 500m underwater. In Lyttelton (where we do sea-trials) divers' vision extends only about 1.5 m making sonar essential for object finding.

Traditionally sonar resolution is determined by the size of physical receiver used. For high-resolution imaging (20 mm X 20 mm) at long range (>200 m) very large (about 10 m long) receivers are needed. SAS uses the forward motion of the sonar to synthesise the larger receiver. This lets the SAS fake using a large receiver with a small one and gives it high, range-independent resolution.

• Professor Peter Gough
• Associate Professor Michael Hayes

University SAS research groups

• SAS group at Herriot Watt

Commercial SAS

• Edgetech are a commercial sidescan sonar company. Recently announced deployment of a SAS system on the Hugin 1000.
• QinetiQ construct and run experimental SAS hardware.
• Geoacoustics are in partnership with QinetiQ on a commercial SAS venture.

Military SAS

• Sonatech have built (build?) experimental SAS systems. They also support Hua Lee's research at UCSB and won the US Navy LMRS contract.
• Northrop Grumman built CSS's SAS and the US-NAVY slow-speed SAS system.
• NATO Undersea Research Centre (NURC), La Spezia, Italy.

Sonar manufacturers

• Reson are a commercial multi-beam echo-sounder and sonar company.